This patch adds a filter_mutex to prevent the filter predicates from
being accessed concurrently by various external functions.
It's based on a previous patch by Li Zefan:
"[PATCH 7/7] tracing/filters: make filter preds RCU safe"
v2 changes:
- fixed wrong value returned in a add_subsystem_pred() failure case
noticed by Li Zefan.
[ Impact: fix trace filter corruption/crashes on parallel access ]
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Tested-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: paulmck@linux.vnet.ibm.com
LKML-Reference: <1239946028.6639.13.camel@tropicana>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Steven Rostedt reported:
> OK, I think I figured this bug out. This is a lockdep issue with respect
> to tracepoints.
>
> The trace points in lockdep are called all the time. Outside the lockdep
> logic. But if lockdep were to trigger an error / warning (which this run
> did) we might be in trouble. For new locks, like the dentry->d_lock, that
> are created, they will not get a name:
>
> void lockdep_init_map(struct lockdep_map *lock, const char *name,
> struct lock_class_key *key, int subclass)
> {
> if (unlikely(!debug_locks))
> return;
>
> When a problem is found by lockdep, debug_locks becomes false. Thus we
> stop allocating names for locks. This dentry->d_lock I had, now has no
> name. Worse yet, I have CONFIG_DEBUG_VM set, that scrambles non
> initialized memory. Thus, when the trace point was hit, it had junk for
> the lock->name, and the machine crashed.
Ah, nice catch. I think we should put at least the name in regardless.
Ensure we at least initialize the trivial entries of the depmap so that
they can be relied upon, even when lockdep itself decided to pack up and
go home.
[ Impact: fix lock tracing after lockdep warnings. ]
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1239954049.23397.4156.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We can find some bugs in the trace events if we stress the writes as well.
The function tracer is a good way to stress the events.
[ Impact: extend scope of event tracer self-tests ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090416161746.604786131@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Export the cached task comms to userspace. This allows user apps to translate
the pids from a trace into their respective task command lines.
[ Impact: let userspace apps reading binary buffer know comm's of pids ]
Signed-off-by: Avadh Patel <avadh4all@gmail.com>
[ added error checking and use of buf pointer to index file_buf ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Currently, every thing needed to read the binary output from the
ring buffers is available, with the exception of the way the ring
buffers handles itself internally.
This patch creates two special files in the debugfs/tracing/events
directory:
# cat /debug/tracing/events/header_page
field: u64 timestamp; offset:0; size:8;
field: local_t commit; offset:8; size:8;
field: char data; offset:16; size:4080;
# cat /debug/tracing/events/header_event
type : 2 bits
len : 3 bits
time_delta : 27 bits
array : 32 bits
padding : type == 0
time_extend : type == 1
data : type == 3
This is to allow a userspace app to see if the ring buffer format changes
or not.
[ Impact: allow userspace apps to know of ringbuffer format changes ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
As events start to become popular, and the new way to add tracing
infrastructure into ftrace, it is important to catch any problems
that might happen with a mistake in the TRACE_EVENT macro.
This patch introduces a startup self test on the registered trace
events. Note, it can only do a generic test, any type of testing that
needs more involement is needed to be implemented by the tracepoint
creators.
The test goes down one by one enabling a trace point and running
some random tasks (random in the sense that I just made them up).
Those tasks are creating threads, grabbing mutexes and spinlocks
and using workqueues.
After testing each event individually, it does the same test after
enabling each system of trace points. Like sched, irq, lockdep.
Then finally it enables all tracepoints and performs the tasks again.
The output to the console on bootup will look like this when everything
works:
Running tests on trace events:
Testing event kfree_skb: OK
Testing event kmalloc: OK
Testing event kmem_cache_alloc: OK
Testing event kmalloc_node: OK
Testing event kmem_cache_alloc_node: OK
Testing event kfree: OK
Testing event kmem_cache_free: OK
Testing event irq_handler_exit: OK
Testing event irq_handler_entry: OK
Testing event softirq_entry: OK
Testing event softirq_exit: OK
Testing event lock_acquire: OK
Testing event lock_release: OK
Testing event sched_kthread_stop: OK
Testing event sched_kthread_stop_ret: OK
Testing event sched_wait_task: OK
Testing event sched_wakeup: OK
Testing event sched_wakeup_new: OK
Testing event sched_switch: OK
Testing event sched_migrate_task: OK
Testing event sched_process_free: OK
Testing event sched_process_exit: OK
Testing event sched_process_wait: OK
Testing event sched_process_fork: OK
Testing event sched_signal_send: OK
Running tests on trace event systems:
Testing event system skb: OK
Testing event system kmem: OK
Testing event system irq: OK
Testing event system lockdep: OK
Testing event system sched: OK
Running tests on all trace events:
Testing all events: OK
[ folded in:
tracing: add #include <linux/delay.h> to fix build failure in test_work()
This build failure occured on a few rare configs:
kernel/trace/trace_events.c: In function ‘test_work’:
kernel/trace/trace_events.c:975: error: implicit declaration of function ‘udelay’
kernel/trace/trace_events.c:980: error: implicit declaration of function ‘msleep’
delay.h is included in way too many other headers, hiding cases
where new usage is added without header inclusion.
[ Impact: build fix ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
]
[ Impact: add event tracer self-tests ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The hooks in the module code for the function tracer must be called
before any of that module code runs. The function tracer hooks
modify the module (replacing calls to mcount to nops). If the code
is executed while the change occurs, then the CPU can take a GPF.
To handle the above with a bit of paranoia, I originally implemented
the hooks as calls directly from the module code.
After examining the notifier calls, it looks as though the start up
notify is called before any of the module's code is executed. This makes
the use of the notify safe with ftrace.
Only the startup notify is required to be "safe". The shutdown simply
removes the entries from the ftrace function list, and does not modify
any code.
This change has another benefit. It removes a issue with a reverse dependency
in the mutexes of ftrace_lock and module_mutex.
[ Impact: fix lock dependency bug, cleanup ]
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: Avoid printing sched_group::__cpu_power for default case
tracing, sched: mark get_parent_ip() notrace
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
kernel/softirq.c: fix sparse warning
rcu: Make hierarchical RCU less IPI-happy
Fix sparse warning in kernel/softirq.c.
warning: do-while statement is not a compound statement
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
LKML-Reference: <BD79186B4FD85F4B8E60E381CAEE1909015F9033@mi8nycmail19.Mi8.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit 46e0bb9c12 ("sched: Print sched_group::__cpu_power
in sched_domain_debug") produces a messy dmesg output while
attempting to print the sched_group::__cpu_power for each
group in the sched_domain hierarchy.
Fix this by avoid printing the __cpu_power for default cases.
(i.e, __cpu_power == SCHED_LOAD_SCALE).
[ Impact: reduce syslog clutter ]
Reported-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Fixed-by: Tony Luck <tony.luck@intel.com>
Cc: a.p.zijlstra@chello.nl
LKML-Reference: <20090414033936.GA534@in.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When current tracer is set to blk tracer, TRACE_ITER_CONTEXT_INFO is
unset, but actually context-info is printed:
pdflush-431 [000] 821.181576: 8,0 P N [pdflush]
And then if we enable TRACE_ITER_CONTEXT_INFO:
# echo context-info > trace_options
We'll see context-info printed twice. What's worse, when we use blk
tracer and trace events at the same time, we'll see no context-info
for trace events at all:
jbd2_commit_logging: dev dm-0:8 transaction 333227
jbd2_end_commit: dev dm-0:8 transaction 333227 head 332814
rm-25433 [001] 9578.307485: 8,18 m N cfq25433 slice expired t=0
rm-25433 [001] 9578.307486: 8,18 m N cfq25433 put_queue
This patch adds blk_tracer->set_flags(), and context-info flag is unset
only when we set the output to classic mode.
Note after this patch, one should unset context-info explicitly if he
wants to get binary output that can be parsed by blkparse:
# echo nocontext-info > trace_options
# echo bin > trace_options
# echo blk > current_tracer
# cat trace_pipe | blkparse -i -
Reported-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <49E54E60.50408@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The previous patch adds support to trace a single partition for
relay+ioctl blktrace, and this patch is for ftrace plugin blktrace:
# echo 1 > /sys/block/sda/sda7/enable
# cat start_lba
102398373
# cat end_lba
102703545
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Shawn Du <duyuyang@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
LKML-Reference: <49E42646.4060608@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Though one can specify '-d /dev/sda1' when using blktrace, it still
traces the whole sda.
To support per-partition tracing, when we start tracing, we initialize
bt->start_lba and bt->end_lba to the start and end sector of that
partition.
Note some actions are per device, thus we don't filter 0-sector events.
The original patch and discussion can be found here:
http://marc.info/?l=linux-btrace&m=122949374214540&w=2
Signed-off-by: Shawn Du <duyuyang@gmail.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
LKML-Reference: <49E42620.4050701@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Don't try and predeclare inline funcs like this:
static inline void wait_migrated_callbacks(void)
...
static void _rcu_barrier(enum rcu_barrier type)
{
...
wait_migrated_callbacks();
}
...
static inline void wait_migrated_callbacks(void)
{
wait_event(rcu_migrate_wq, !atomic_read(&rcu_migrate_type_count));
}
as it upsets some versions of gcc under some circumstances:
kernel/rcupdate.c: In function `_rcu_barrier':
kernel/rcupdate.c:125: sorry, unimplemented: inlining failed in call to 'wait_migrated_callbacks': function body not available
kernel/rcupdate.c:152: sorry, unimplemented: called from here
This can be dealt with by simply putting the static variables (rcu_migrate_*)
at the top, and moving the implementation of the function up so that it
replaces its forward declaration.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: clean up
Create a sub directory in include/trace called events to keep the
trace point headers in their own separate directory. Only headers that
declare trace points should be defined in this directory.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Impact: compile fix
The addition of TRACE_EVENT for modules breaks the build for when
modules are disabled. This code fixes that.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Impact: allow modules to add TRACE_EVENTS on load
This patch adds the final hooks to allow modules to use the TRACE_EVENT
macro. A notifier and a data structure are used to link the TRACE_EVENTs
defined in the module to connect them with the ftrace event tracing system.
It also adds the necessary automated clean ups to the trace events when a
module is removed.
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Impact: let modules add trace events
The trace event code requires some functions to be exported to allow
modules to use TRACE_EVENT. This patch adds EXPORT_SYMBOL_GPL to the
necessary functions.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Impact: makes it possible to define events in modules
The events are created by reading down the section that they are linked
in by the macros. But this is not scalable to modules. This patch converts
the manipulations to use a global link list, and on boot up it adds
the items in the section to the list.
This change will allow modules to add their tracing events to the list as
well.
Note, this change alone does not permit modules to use the TRACE_EVENT macros,
but the change is needed for them to eventually do so.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This patch moves the ftrace creation into include/trace/ftrace.h and
simplifies the work of developers in adding new tracepoints.
Just the act of creating the trace points in include/trace and including
define_trace.h will create the events in the debugfs/tracing/events
directory.
This patch removes the need of include/trace/trace_events.h
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
In preparation to allowing trace events to happen in modules, we need
to move some of the local declarations in the kernel/trace directory
into include/linux.
This patch simply moves the declarations and performs no context changes.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
In the process to make TRACE_EVENT macro work for modules, the trace_seq
operations must be available for core kernel code.
These operations are quite useful and can be used for other implementations.
The main idea is that we create a trace_seq handle that acts very much
like the seq_file handle.
struct trace_seq *s = kmalloc(sizeof(*s, GFP_KERNEL);
trace_seq_init(s);
trace_seq_printf(s, "some data %d\n", variable);
printk("%s", s->buffer);
The main use is to allow a top level function call several other functions
that may store printf like data into the buffer. Then at the end, the top
level function can process all the data with any method it would like to.
It could be passed to userspace, output via printk or even use seq_file:
trace_seq_to_user(s, ubuf, cnt);
seq_puts(m, s->buffer);
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This patch lowers the number of places a developer must modify to add
new tracepoints. The current method to add a new tracepoint
into an existing system is to write the trace point macro in the
trace header with one of the macros TRACE_EVENT, TRACE_FORMAT or
DECLARE_TRACE, then they must add the same named item into the C file
with the macro DEFINE_TRACE(name) and then add the trace point.
This change cuts out the needing to add the DEFINE_TRACE(name).
Every file that uses the tracepoint must still include the trace/<type>.h
file, but the one C file must also add a define before the including
of that file.
#define CREATE_TRACE_POINTS
#include <trace/mytrace.h>
This will cause the trace/mytrace.h file to also produce the C code
necessary to implement the trace point.
Note, if more than one trace/<type>.h is used to create the C code
it is best to list them all together.
#define CREATE_TRACE_POINTS
#include <trace/foo.h>
#include <trace/bar.h>
#include <trace/fido.h>
Thanks to Mathieu Desnoyers and Christoph Hellwig for coming up with
the cleaner solution of the define above the includes over my first
design to have the C code include a "special" header.
This patch converts sched, irq and lockdep and skb to use this new
method.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Jeremy Fitzhardinge reported this build failure:
LD .tmp_vmlinux1
arch/x86/kernel/built-in.o: In function `ds_take_timestamp':
git/linux/arch/x86/kernel/ds.c:1380: undefined reference to `trace_clock_global'
git/linux/arch/x86/kernel/ds.c:1380: undefined reference to `trace_clock_global'
Which is due to !CONFIG_TRACING && CONFIG_X86_DS=y.
Expose the trace clock code to CONFIG_X86_DS as well.
[ Unfortunately librarizing doesnt work well - ancient architectures
with no raw_local_irq_save() primitive break the build. ]
Reported-by: Jeremy Fitzhardinge <jeremy@goop.org>
LKML-Reference: <49E4413F.7070700@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: clean up
Neil Horman (et. al.) criticized the way the trace events were broken up
into two files. The reason for that was that ftrace needed to separate out
the declarations from where the #include <linux/tracepoint.h> was used.
It then dawned on me that the tracepoint.h header only needs to define the
TRACE_EVENT macro if it is not already defined.
The solution is simply to test if TRACE_EVENT is defined, and if it is not
then the linux/tracepoint.h header can define it. This change consolidates
all the <traces>.h and <traces>_event_types.h into the <traces>.h file.
Reported-by: Neil Horman <nhorman@tuxdriver.com>
Reported-by: Theodore Tso <tytso@mit.edu>
Reported-by: Jiaying Zhang <jiayingz@google.com>
Cc: Zhaolei <zhaolei@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
As discussed in the thread here:
http://marc.info/?l=linux-kernel&m=123964468521142&w=2
Eric W. Biederman observed:
> It looks like some additional bugs have slipped in since last I looked.
>
> set_irq_affinity does this:
> ifdef CONFIG_GENERIC_PENDING_IRQ
> if (desc->status & IRQ_MOVE_PCNTXT || desc->status & IRQ_DISABLED) {
> cpumask_copy(desc->affinity, cpumask);
> desc->chip->set_affinity(irq, cpumask);
> } else {
> desc->status |= IRQ_MOVE_PENDING;
> cpumask_copy(desc->pending_mask, cpumask);
> }
> #else
>
> That IRQ_DISABLED case is a software state and as such it has nothing to
> do with how safe it is to move an irq in process context.
[...]
>
> The only reason we migrate MSIs in interrupt context today is that there
> wasn't infrastructure for support migration both in interrupt context
> and outside of it.
Yes. The idea here was to force the MSI migration to happen in process
context. One of the patches in the series did
disable_irq(dev->irq);
irq_set_affinity(dev->irq, cpumask_of(dev->cpu));
enable_irq(dev->irq);
with the above patch adding irq/manage code check for interrupt disabled
and moving the interrupt in process context.
IIRC, there was no IRQ_MOVE_PCNTXT when we were developing this HPET
code and we ended up having this ugly hack. IRQ_MOVE_PCNTXT was there
when we eventually submitted the patch upstream. But, looks like I did a
blind rebasing instead of using IRQ_MOVE_PCNTXT in hpet MSI code.
Below patch fixes this. i.e., revert commit 932775a4ab
and add PCNTXT to HPET MSI setup. Also removes copying of desc->affinity
in generic code as set_affinity routines are doing it internally.
Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Li Shaohua" <shaohua.li@intel.com>
Cc: Gary Hade <garyhade@us.ibm.com>
Cc: "lcm@us.ibm.com" <lcm@us.ibm.com>
Cc: suresh.b.siddha@intel.com
LKML-Reference: <20090413222058.GB8211@linux-os.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch fixes a hierarchical-RCU performance bug located by Anton
Blanchard. The problem stems from a misguided attempt to provide a
work-around for jiffies-counter failure. This work-around uses a per-CPU
n_rcu_pending counter, which is incremented on each call to rcu_pending(),
which in turn is called from each scheduling-clock interrupt. Each CPU
then treats this counter as a surrogate for the jiffies counter, so
that if the jiffies counter fails to advance, the per-CPU n_rcu_pending
counter will cause RCU to invoke force_quiescent_state(), which in turn
will (among other things) send resched IPIs to CPUs that have thus far
failed to pass through an RCU quiescent state.
Unfortunately, each CPU resets only its own counter after sending a
batch of IPIs. This means that the other CPUs will also (needlessly)
send -another- round of IPIs, for a full N-squared set of IPIs in the
worst case every three scheduler-clock ticks until the grace period
finally ends. It is not reasonable for a given CPU to reset each and
every n_rcu_pending for all the other CPUs, so this patch instead simply
disables the jiffies-counter "training wheels", thus eliminating the
excessive IPIs.
Note that the jiffies-counter IPIs do not have this problem due to
the fact that the jiffies counter is global, so that the CPU sending
the IPIs can easily reset things, thus preventing the other CPUs from
sending redundant IPIs.
Note also that the n_rcu_pending counter remains, as it will continue to
be used for tracing. It may also see use to update the jiffies counter,
should an appropriate kick-the-jiffies-counter API appear.
Located-by: Anton Blanchard <anton@au1.ibm.com>
Tested-by: Anton Blanchard <anton@au1.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: anton@samba.org
Cc: akpm@linux-foundation.org
Cc: dipankar@in.ibm.com
Cc: manfred@colorfullife.com
Cc: cl@linux-foundation.org
Cc: josht@linux.vnet.ibm.com
Cc: schamp@sgi.com
Cc: niv@us.ibm.com
Cc: dvhltc@us.ibm.com
Cc: ego@in.ibm.com
Cc: laijs@cn.fujitsu.com
Cc: rostedt@goodmis.org
Cc: peterz@infradead.org
Cc: penberg@cs.helsinki.fi
Cc: andi@firstfloor.org
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
LKML-Reference: <12396834793575-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: remove overly redundant tracing entries
When tracer is "function" or "function_graph", way too much
"get_parent_ip" entries are recorded in ring_buffer.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <49D458B1.5000703@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Pointed out by Roland. The bug was recently introduced by me in
"forget_original_parent: split out the un-ptrace part", commit
39c626ae47.
Since that patch we have a window after exit_ptrace() drops tasklist and
before forget_original_parent() takes it again. In this window the child
can do ptrace(PTRACE_TRACEME) and nobody can untrace this child after
that.
Change ptrace_traceme() to not attach to the exiting ->real_parent. We
don't report the error in this case, we pretend we attach right before
->real_parent calls exit_ptrace() which should untrace us anyway.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
vm knobs should go in the vm table. Probably too late for
randomize_va_space though.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch allows event filters to be safely removed or switched
on-the-fly while avoiding the use of rcu or the suspension of tracing of
previous versions.
It does it by adding a new filter_pred_none() predicate function which
does nothing and by never deallocating either the predicates or any of
the filter_pred members used in matching; the predicate lists are
allocated and initialized during ftrace_event_calls initialization.
Whenever a filter is removed or replaced, the filter_pred_* functions
currently in use by the affected ftrace_event_call are immediately
switched over to to the filter_pred_none() function, while the rest of
the filter_pred members are left intact, allowing any currently
executing filter_pred_* functions to finish up, using the values they're
currently using.
In the case of filter replacement, the new predicate values are copied
into the old predicates after the above step, and the filter_pred_none()
functions are replaced by the filter_pred_* functions for the new
filter. In this case, it is possible though very unlikely that a
previous filter_pred_* is still running even after the
filter_pred_none() switch and the switch to the new filter_pred_*. In
that case, however, because nothing has been deallocated in the
filter_pred, the worst that can happen is that the old filter_pred_*
function sees the new values and as a result produces either a false
positive or a false negative, depending on the values it finds.
So one downside to this method is that rarely, it can produce a bad
match during the filter switch, but it should be possible to live with
that, IMHO.
The other downside is that at least in this patch the predicate lists
are always pre-allocated, taking up memory from the start. They could
probably be allocated on first-use, and de-allocated when tracing is
completely stopped - if this patch makes sense, I could create another
one to do that later on.
Oh, and it also places a restriction on the size of __arrays in events,
currently set to 128, since they can't be larger than the now embedded
str_val arrays in the filter_pred struct.
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: paulmck@linux.vnet.ibm.com
LKML-Reference: <1239610670.6660.49.camel@tropicana>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch changes filter_check_discard() to make use of the new
ring_buffer_discard_commit() function and modifies the current users to
call the old commit function in the non-discard case.
It also introduces a version of filter_check_discard() that uses the
global trace buffer (filter_current_check_discard()) for those cases.
v2 changes:
- fix compile error noticed by Ingo Molnar
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: fweisbec@gmail.com
LKML-Reference: <1239178554.10295.36.camel@tropicana>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add a new config option, CONFIG_EVENT_TRACING that gets selected
when CONFIG_TRACING is selected and adds everything needed by the stuff
in trace_export - basically all the event tracing support needed by e.g.
bprint, minus the actual events, which are only included if
CONFIG_EVENT_TRACER is selected.
So CONFIG_EVENT_TRACER can be used to turn on or off the generated events
(what I think of as the 'event tracer'), while CONFIG_EVENT_TRACING turns
on or off the base event tracing support used by both the event tracer and
the other things such as bprint that can't be configured out.
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: fweisbec@gmail.com
LKML-Reference: <1239178441.10295.34.camel@tropicana>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The ring_buffer_discard_commit makes better usage of the ring_buffer
when an event has been discarded. It tries to remove it completely if
possible.
This patch converts the trace event filtering to use
ring_buffer_discard_commit instead of the ring_buffer_event_discard.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The ring_buffer_discard_commit is similar to ring_buffer_event_discard
but it can only be done on an event that has yet to be commited.
Unpredictable results can happen otherwise.
The main difference between ring_buffer_discard_commit and
ring_buffer_event_discard is that ring_buffer_discard_commit will try
to free the data in the ring buffer if nothing has addded data
after the reserved event. If something did, then it acts almost the
same as ring_buffer_event_discard followed by a
ring_buffer_unlock_commit.
Note, either ring_buffer_commit_discard and ring_buffer_unlock_commit
can be called on an event, not both.
This commit also exports both discard functions to be usable by
GPL modules.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Frederic Weisbecker suggested that the trace_special event shouldn't be
filterable; this patch adds a TRACE_EVENT_FORMAT_NOFILTER event macro
that allows an event format to be exported without having a filter
attached, and removes filtering from the trace_special event.
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds run-time field descriptions to all the event formats
exported using TRACE_EVENT_FORMAT. It also hooks up all the tracers
that use them (i.e. the tracers in the 'ftrace subsystem') so they can
also have their output filtered by the event-filtering mechanism.
When I was testing this, there were a couple of things that fooled me
into thinking the filters weren't working, when actually they were -
I'll mention them here so others don't make the same mistakes (and file
bug reports. ;-)
One is that some of the tracers trace multiple events e.g. the
sched_switch tracer uses the context_switch and wakeup events, and if
you don't set filters on all of the traced events, the unfiltered output
from the events without filters on them can make it look like the
filtering as a whole isn't working properly, when actually it is doing
what it was asked to do - it just wasn't asked to do the right thing.
The other is that for the really high-volume tracers e.g. the function
tracer, the volume of filtered events can be so high that it pushes the
unfiltered events out of the ring buffer before they can be read so e.g.
cat'ing the trace file repeatedly shows either no output, or once in
awhile some output but that isn't there the next time you read the
trace, which isn't what you normally expect when reading the trace file.
If you read from the trace_pipe file though, you can catch them before
they disappear.
Changes from v1:
As suggested by Frederic Weisbecker:
- get rid of externs in functions
- added unlikely() to filter_check_discard()
Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Before patch:
# tracer: power
#
# TASK-PID CPU# TIMESTAMP FUNCTION
# | | | | |
[ 676.875865889] CSTATE: Going to C1 on cpu 0 for 0.005911463
[ 676.882938805] CSTATE: Going to C1 on cpu 0 for 0.104796532
...
After patch:
# tracer: power
#
# TIMESTAMP STATE EVENT
# | | |
[ 676.875865889] CSTATE: Going to C1 on cpu 0 for 0.005911463
[ 676.882938805] CSTATE: Going to C1 on cpu 0 for 0.104796532
...
v2: Use seq_puts instead of seq_printf
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <49E2E889.5000903@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There is a race between resume from hibernation and the asynchronous
scanning of SCSI devices and to prevent it from happening we need to
call scsi_complete_async_scans() during resume from hibernation.
In addition, if the resume from hibernation is userland-driven, it's
better to wait for all device probes in the kernel to complete before
attempting to open the resume device.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing/filters: return proper error code when writing filter file
tracing/filters: allow user input integer to be oct or hex
tracing/filters: fix NULL pointer dereference
tracing/filters: NIL-terminate user input filter
ftrace: Output REC->var instead of __entry->var for trace format
Make __stringify support variable argument macros too
tracing: fix document references
tracing: fix splice return too large
tracing: update file->f_pos when splice(2) it
tracing: allocate page when needed
tracing: disable seeking for trace_pipe_raw
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
lockdep: continue lock debugging despite some taints
lockdep: warn about lockdep disabling after kernel taint
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
percpu: unbreak alpha percpu
mutex: have non-spinning mutexes on s390 by default
Impact: broaden lockdep checks
Lockdep is disabled after any kernel taints. This might be convenient
to ignore bad locking issues which sources come from outside the kernel
tree. Nevertheless, it might be a frustrating experience for the
staging developers or those who experience a warning but are focused
on another things that require lockdep.
The v2 of this patch simply don't disable anymore lockdep in case
of TAINT_CRAP and TAINT_WARN events.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: LTP <ltp-list@lists.sourceforge.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg KH <gregkh@suse.de>
LKML-Reference: <1239412638-6739-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: provide useful missing info for developers
Kernel taint can occur in several situations such as warnings,
load of prorietary or staging modules, bad page, etc...
But when such taint happens, a developer might still be working on
the kernel, expecting that lockdep is still enabled. But a taint
disables lockdep without ever warning about it.
Such a kernel behaviour doesn't really help for kernel development.
This patch adds this missing warning.
Since the taint is done most of the time after the main message that
explain the real source issue, it seems safe to warn about it inside
add_taint() so that it appears at last, without hurting the main
information.
v2: Use a generic helper to disable lockdep instead of an
open coded xchg().
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1239412638-6739-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
BLK_TC_PC events should be treated differently with BLK_TC_FS events.
Before this patch:
# echo 1 > /sys/block/sda/sda1/trace/enable
# echo pc > /sys/block/sda/sda1/trace/act_mask
# echo blk > /debugfs/tracing/current_tracer
# (generate some BLK_TC_PC events)
# cat trace
bash-2184 [000] 1774.275413: 8,7 I N [bash]
bash-2184 [000] 1774.275435: 8,7 D N [bash]
bash-2184 [000] 1774.275540: 8,7 I R [bash]
bash-2184 [000] 1774.275547: 8,7 D R [bash]
ksoftirqd/0-4 [000] 1774.275580: 8,7 C N 0 [0]
bash-2184 [000] 1774.275648: 8,7 I R [bash]
bash-2184 [000] 1774.275653: 8,7 D R [bash]
ksoftirqd/0-4 [000] 1774.275682: 8,7 C N 0 [0]
bash-2184 [000] 1774.275739: 8,7 I R [bash]
bash-2184 [000] 1774.275744: 8,7 D R [bash]
ksoftirqd/0-4 [000] 1774.275771: 8,7 C N 0 [0]
bash-2184 [000] 1774.275804: 8,7 I R [bash]
bash-2184 [000] 1774.275808: 8,7 D R [bash]
ksoftirqd/0-4 [000] 1774.275836: 8,7 C N 0 [0]
After this patch:
# cat trace
bash-2263 [000] 366.782149: 8,7 I N 0 (00 ..) [bash]
bash-2263 [000] 366.782323: 8,7 D N 0 (00 ..) [bash]
bash-2263 [000] 366.782557: 8,7 I R 8 (25 00 ..) [bash]
bash-2263 [000] 366.782560: 8,7 D R 8 (25 00 ..) [bash]
ksoftirqd/0-4 [000] 366.782582: 8,7 C N (25 00 ..) [0]
bash-2263 [000] 366.782648: 8,7 I R 8 (5a 00 3f 00) [bash]
bash-2263 [000] 366.782650: 8,7 D R 8 (5a 00 3f 00) [bash]
ksoftirqd/0-4 [000] 366.782669: 8,7 C N (5a 00 3f 00) [0]
bash-2263 [000] 366.782710: 8,7 I R 8 (5a 00 08 00) [bash]
bash-2263 [000] 366.782713: 8,7 D R 8 (5a 00 08 00) [bash]
ksoftirqd/0-4 [000] 366.782730: 8,7 C N (5a 00 08 00) [0]
bash-2263 [000] 366.783375: 8,7 I R 36 (5a 00 08 00) [bash]
bash-2263 [000] 366.783379: 8,7 D R 36 (5a 00 08 00) [bash]
ksoftirqd/0-4 [000] 366.783404: 8,7 C N (5a 00 08 00) [0]
This is what we do with PC events in user-space blktrace.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <49D32387.9040106@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Not all events are pc (packet command) events. An event is a pc
event only if it has BLK_TC_PC bit set.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <49D3236D.3090705@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: refactor code for future changes
Current kmemtrace.h is used both as header file of kmemtrace and kmem's
tracepoints definition.
Tracepoints' definition file may be used by other code, and should only have
definition of tracepoint.
We can separate include/trace/kmemtrace.h into 2 files:
include/linux/kmemtrace.h: header file for kmemtrace
include/trace/kmem.h: definition of kmem tracepoints
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Acked-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <49DEE68A.5040902@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
- propagate return value of filter_add_pred() to the user
- return -ENOSPC but not -ENOMEM or -EINVAL when the filter array
is full
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Tom Zanussi <tzanussi@gmail.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <49E04CF0.3010105@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Make sure messages from user space are NIL-terminated strings,
otherwise we could dump random memory while reading filter file.
Try this:
# echo 'parent_comm ==' > events/sched/sched_process_fork/filter
# cat events/sched/sched_process_fork/filter
parent_comm == �
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Tom Zanussi <tzanussi@gmail.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <49E04C32.6060508@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Several drivers use asynchronous work to do device discovery, and we
synchronize with them in the compiled-in case before we actually try to
mount root filesystems etc.
However, when compiled as modules, that synchronization is missing - the
module loading completes, but the driver hasn't actually finished
probing for devices, and that means that any user mode that expects to
use the devices after the 'insmod' is now potentially broken.
We already saw one case of a similar issue in the ACPI battery code,
where the kernel itself expected the module to be all done, and unmapped
the init memory - but the async device discovery was still running.
That got hacked around by just removing the "__init" (see commit
5d38258ec0 "ACPI battery: fix async boot
oops"), but the real fix is to just make the module loading wait for all
async work to be completed.
It will slow down module loading, but since common devices should be
built in anyway, and since the bug is really annoying and hard to handle
from user space (and caused several S3 resume regressions), the simple
fix to wait is the right one.
This fixes at least
http://bugzilla.kernel.org/show_bug.cgi?id=13063
but probably a few other bugzilla entries too (12936, for example), and
is confirmed to fix Rafael's storage driver breakage after resume bug
report (no bugzilla entry).
We should also be able to now revert that ACPI battery fix.
Reported-and-tested-by: Rafael J. Wysocki <rjw@suse.com>
Tested-by: Heinz Diehl <htd@fancy-poultry.org>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When moving documents to Documentation/trace/, I forgot to
grep Kconfig to find out those references.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Pekka Paalanen <pq@iki.fi>
Cc: eduard.munteanu@linux360.ro
LKML-Reference: <49DE97EF.7080208@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
While trying to optimize the new lock on reiserfs to replace
the bkl, I find the lock tracing very useful though it lacks
something important for performance (and latency) instrumentation:
the time a task waits for a lock.
That's what this patch implements:
bash-4816 [000] 202.652815: lock_contended: lock_contended: &sb->s_type->i_mutex_key
bash-4816 [000] 202.652819: lock_acquired: &rq->lock (0.000 us)
<...>-4787 [000] 202.652825: lock_acquired: &rq->lock (0.000 us)
<...>-4787 [000] 202.652829: lock_acquired: &rq->lock (0.000 us)
bash-4816 [000] 202.652833: lock_acquired: &sb->s_type->i_mutex_key (16.005 us)
As shown above, the "lock acquired" field is followed by the time
it has been waiting for the lock. Usually, a lock contended entry
is followed by a near lock_acquired entry with a non-zero time waited.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1238975373-15739-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge reason: pick up both v2.6.30-rc1 [which includes tracing/urgent fixes]
and pick up the current lineup of tracing/urgent fixes as well
Signed-off-by: Ingo Molnar <mingo@elte.hu>
I got these from strace:
splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 12288
splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 12288
splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 12288
splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 16384
splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 8192
splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 8192
splice(0x3, 0, 0x5, 0, 0x1000, 0x1) = 8192
I wanted to splice_read 4096 bytes, but it returns 8192 or larger.
It is because the return value of tracing_buffers_splice_read()
does not include "zero out any left over data" bytes.
But tracing_buffers_read() includes these bytes, we make them
consistent.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <49D46674.9030804@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: Cleanup
These two lines:
if (unlikely(*ppos))
return -ESPIPE;
in tracing_buffers_splice_read() are not needed, VFS layer
has disabled seek(2).
We remove these two lines, and then we can update file->f_pos.
And tracing_buffers_read() updates file->f_pos, this fix
make tracing_buffers_splice_read() updates file->f_pos too.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <49D46670.4010503@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: Cleanup
Sometimes, we open trace_pipe_raw, but we don't read(2) it,
we just splice(2) it, thus, the page is not used.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <49D4666B.4010608@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: disable pread()
We set tracing_buffers_fops.llseek to no_llseek,
but we can still perform pread() to read this file.
That is not expected.
This fix uses nonseekable_open() to disable it.
tracing_buffers_fops.llseek is still set to no_llseek,
it mark this file is a "non-seekable device" and is used by
sys_splice(). See also do_splice() or manual of splice(2):
ERRORS
EINVAL Target file system doesn't support splicing;
neither of the descriptors refers to a pipe;
or offset given for non-seekable device.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <49D46668.8030806@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: consolidate documents
blktrace: pass the right pointer to kfree()
tracing/syscalls: use a dedicated file header
tracing: append a comma to INIT_FTRACE_GRAPH
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: do not count frozen tasks toward load
sched: refresh MAINTAINERS entry
sched: Print sched_group::__cpu_power in sched_domain_debug
cpuacct: add per-cgroup utime/stime statistics
posixtimers, sched: Fix posix clock monotonicity
sched_rt: don't allocate cpumask in fastpath
cpuacct: make cpuacct hierarchy walk in cpuacct_charge() safe when rcupreempt is used -v2
Impact: performance regression fix for s390
The adaptive spinning mutexes will not always do what one would expect on
virtualized architectures like s390. Especially the cpu_relax() loop in
mutex_spin_on_owner might hurt if the mutex holding cpu has been scheduled
away by the hypervisor.
We would end up in a cpu_relax() loop when there is no chance that the
state of the mutex changes until the target cpu has been scheduled again by
the hypervisor.
For that reason we should change the default behaviour to no-spin on s390.
We do have an instruction which allows to yield the current cpu in favour of
a different target cpu. Also we have an instruction which allows us to figure
out if the target cpu is physically backed.
However we need to do some performance tests until we can come up with
a solution that will do the right thing on s390.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
LKML-Reference: <20090409184834.7a0df7b2@osiris.boeblingen.de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix kfree crash with non-standard act_mask string
If passing a string with leading white spaces to strstrip(),
the returned ptr != the original ptr.
This bug was introduced by me.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <49DD694C.8020902@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix build warnings and possibe compat misbehavior on IA64
Building a kernel on ia64 might trigger these ugly build warnings:
CC arch/ia64/ia32/sys_ia32.o
In file included from arch/ia64/ia32/sys_ia32.c:55:
arch/ia64/ia32/ia32priv.h:290:1: warning: "elf_check_arch" redefined
In file included from include/linux/elf.h:7,
from include/linux/module.h:14,
from include/linux/ftrace.h:8,
from include/linux/syscalls.h:68,
from arch/ia64/ia32/sys_ia32.c:18:
arch/ia64/include/asm/elf.h:19:1: warning: this is the location of the previous definition
[...]
sys_ia32.c includes linux/syscalls.h which in turn includes linux/ftrace.h
to import the syscalls tracing prototypes.
But including ftrace.h can pull too much things for a low level file,
especially on ia64 where the ia32 private headers conflict with higher
level headers.
Now we isolate the syscall tracing headers in their own lightweight file.
Reported-by: Tony Luck <tony.luck@intel.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jason Baron <jbaron@redhat.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Michael Rubin <mrubin@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Michael Davidson <md@google.com>
LKML-Reference: <20090408184058.GB6017@nowhere>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: circular locking bugfix
The various implemetnations and proposed implemetnations of work_on_cpu()
are vulnerable to various deadlocks because they all used queues of some
form.
Unrelated pieces of kernel code thus gained dependencies wherein if one
work_on_cpu() caller holds a lock which some other work_on_cpu() callback
also takes, the kernel could rarely deadlock.
Fix this by creating a short-lived kernel thread for each work_on_cpu()
invokation.
This is not terribly fast, but the only current caller of work_on_cpu() is
pci_call_probe().
It would be nice to find some other way of doing the node-local
allocations in the PCI probe code so that we can zap work_on_cpu()
altogether. The code there is rather nasty. I can't think of anything
simple at this time...
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
kthreadd is the single thread which implements ths "create" request, move
sched_setscheduler/etc from create_kthread() to kthread_create() to
improve the scalability.
We should be careful with sched_setscheduler(), use _nochek helper.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Vitaliy Gusev <vgusev@openvz.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Remove the unnecessary find_task_by_pid_ns(). kthread() can just
use "current" to get the same result.
Signed-off-by: Vitaliy Gusev <vgusev@openvz.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This fixes all the checkpatch --file complaints about kernel/ptrace.c
and also removes an unused #include. I've verified that there are no
changes to the compiled code on x86_64.
Signed-off-by: Roland McGrath <roland@redhat.com>
[ Removed the parts that just split a line - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
update_rlimit_cpu() tries to optimize out set_process_cpu_timer() in case
when we already have CPUCLOCK_PROF timer which should expire first. But it
uses cputime_lt() instead of cputime_gt().
Test case:
int main(void)
{
struct itimerval it = {
.it_value = { .tv_sec = 1000 },
};
assert(!setitimer(ITIMER_PROF, &it, NULL));
struct rlimit rl = {
.rlim_cur = 1,
.rlim_max = 1,
};
assert(!setrlimit(RLIMIT_CPU, &rl));
for (;;)
;
return 0;
}
Without this patch, the task is not killed as RLIMIT_CPU demands.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Peter Lojkin <ia6432@inbox.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: stable@kernel.org
LKML-Reference: <20090327000610.GA10108@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
See http://bugzilla.kernel.org/show_bug.cgi?id=12911
copy_signal() copies signal->rlim, but RLIMIT_CPU is "lost". Because
posix_cpu_timers_init_group() sets cputime_expires.prof_exp = 0 and thus
fastpath_timer_check() returns false unless we have other expired cpu timers.
Change copy_signal() to set cputime_expires.prof_exp if we have RLIMIT_CPU.
Also, set cputimer.running = 1 in that case. This is not strictly necessary,
but imho makes sense.
Reported-by: Peter Lojkin <ia6432@inbox.ru>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Peter Lojkin <ia6432@inbox.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: stable@kernel.org
LKML-Reference: <20090327000607.GA10104@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'core/softlockup' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
softlockup: make DETECT_HUNG_TASK default depend on DETECT_SOFTLOCKUP
softlockup: move 'one' to the softlockup section in sysctl.c
softlockup: ensure the task has been switched out once
softlockup: remove timestamp checking from hung_task
softlockup: convert read_lock in hung_task to rcu_read_lock
softlockup: check all tasks in hung_task
softlockup: remove unused definition for spawn_softlockup_task
softlockup: fix potential race in hung_task when resetting timeout
softlockup: fix to allow compiling with !DETECT_HUNG_TASK
softlockup: decouple hung tasks check from softlockup detection
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
branch tracer, intel-iommu: fix build with CONFIG_BRANCH_TRACER=y
branch tracer: Fix for enabling branch profiling makes sparse unusable
ftrace: Correct a text align for event format output
Update /debug/tracing/README
tracing/ftrace: alloc the started cpumask for the trace file
tracing, x86: remove duplicated #include
ftrace: Add check of sched_stopped for probe_sched_wakeup
function-graph: add proper initialization for init task
tracing/ftrace: fix missing include string.h
tracing: fix incorrect return type of ns2usecs()
tracing: remove CALLER_ADDR2 from wakeup tracer
blktrace: fix pdu_len when tracing packet command requests
blktrace: small cleanup in blk_msg_write()
blktrace: NUL-terminate user space messages
tracing: move scripts/trace/power.pl to scripts/tracing/power.pl
* 'irq/threaded' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
genirq: fix devres.o build for GENERIC_HARDIRQS=n
genirq: provide old request_irq() for CONFIG_GENERIC_HARDIRQ=n
genirq: threaded irq handlers review fixups
genirq: add support for threaded interrupts to devres
genirq: add threaded interrupt handler support
Add disable_kprobe() and enable_kprobe() to disable/enable kprobes
temporarily.
disable_kprobe() asynchronously disables probe handlers of specified
kprobe. So, after calling it, some handlers can be called at a while.
enable_kprobe() enables specified kprobe.
aggr_pre_handler and aggr_post_handler check disabled probes. On the
other hand aggr_break_handler and aggr_fault_handler don't check it
because these handlers will be called while executing pre or post handlers
and usually those help error handling.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename kprobe_enabled to kprobes_all_disarmed and invert logic due to
avoiding naming confusion from per-probe disabling.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clean up positions of EXPORT_SYMBOL_GPL in kernel/kprobes.c according to
checkpatch.pl.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, kprobes can disable all probes at once, but can't disable it
individually (not unregister, just disable an kprobe, because
unregistering needs to wait for scheduler synchronization). These patches
introduce APIs for on-the-fly per-probe disabling and re-enabling by
dis-arming/re-arming its breakpoint instruction.
This patch:
Change old_p to ap in add_new_kprobe() for readability, copy flags member
in add_aggr_kprobe(), and simplify the code flow of
register_aggr_kprobe().
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add /proc entries to give the admin the ability to control the minimum and
maximum number of pdflush threads. This allows finer control of pdflush
on both large and small machines.
The rationale is simply one size does not fit all. Admins on large and/or
small systems may want to tune the min/max pdflush thread count to best
suit their needs. Right now the min/max is hardcoded to 2/8. While
probably a fair estimate for smaller machines, large machines with large
numbers of CPUs and large numbers of filesystems/block devices may benefit
from larger numbers of threads working on different block devices.
Even if the background flushing algorithm is radically changed, it is
still likely that multiple threads will be involved and admins would still
desire finer control on the min/max other than to have to recompile the
kernel.
The patch adds '/proc/sys/vm/nr_pdflush_threads_min' and
'/proc/sys/vm/nr_pdflush_threads_max' with r/w permissions.
The minimum value for nr_pdflush_threads_min is 1 and the maximum value is
the current value of nr_pdflush_threads_max. This minimum is required
since additional thread creation is performed in a pdflush thread itself.
The minimum value for nr_pdflush_threads_max is the current value of
nr_pdflush_threads_min and the maximum value can be 1000.
Documentation/sysctl/vm.txt is also updated.
[akpm@linux-foundation.org: fix comment, fix whitespace, use __read_mostly]
Signed-off-by: Peter W Morreale <pmorreale@novell.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Unify sched_switch and sched_wakeup's action to following logic:
Do record_cmdline when start_cmdline_record() is called.
Start tracing events when the tracer is started.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
LKML-Reference: <49D1C596.5050203@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Impact: cleanup
The variable ftrace_graph_active is only modified under the
ftrace_lock mutex, thus an atomic is not necessary for modification.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Impact: cleanup
Most of the tracing files creation follow the same pattern:
ret = debugfs_create_file(...)
if (!ret)
pr_warning("Couldn't create ... entry\n")
Unify it!
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1238109938-11840-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Impact: cleanup
Use USEC_PER_SEC and NSEC_PER_SEC instead of 1000000 and 1000000000.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <49CC7870.9000309@cn.fujitsu.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Some of the tracers have been renamed, which was not updated in the in-kernel
run-time README file. Update it.
Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
LKML-Reference: <200903231158.32151.knikanth@suse.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix a crash while cat trace file
Currently we are using a cpumask to remind each cpu where a
trace occured. It lets us notice the user that a cpu just had
its first trace.
But on latest -tip we have the following crash once we cat the trace
file:
IP: [<c0270c4a>] print_trace_fmt+0x45/0xe7
*pde = 00000000
Oops: 0000 [#1] PREEMPT SMP
last sysfs file: /sys/class/net/eth0/carrier
Pid: 3897, comm: cat Not tainted (2.6.29-tip-02825-g0f22972-dirty #81)
EIP: 0060:[<c0270c4a>] EFLAGS: 00010297 CPU: 0
EIP is at print_trace_fmt+0x45/0xe7
EAX: 00000000 EBX: 00000000 ECX: c12d9e98 EDX: ccdb7010
ESI: d31f4000 EDI: 00322401 EBP: d31f3f10 ESP: d31f3efc
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process cat (pid: 3897, ti=d31f2000 task=d3b3cf20 task.ti=d31f2000)
Stack:
d31f4080 ccdb7010 d31f4000 d691fe70 ccdb7010 d31f3f24 c0270e5c d31f4000
d691fe70 d31f4000 d31f3f34 c02718e8 c12d9e98 d691fe70 d31f3f70 c02bfc33
00001000 09130000 d3b46e00 d691fe98 00000000 00000079 00000001 00000000
Call Trace:
[<c0270e5c>] ? print_trace_line+0x170/0x17c
[<c02718e8>] ? s_show+0xa7/0xbd
[<c02bfc33>] ? seq_read+0x24a/0x327
[<c02bf9e9>] ? seq_read+0x0/0x327
[<c02ab18b>] ? vfs_read+0x86/0xe1
[<c02ab289>] ? sys_read+0x40/0x65
[<c0202d8f>] ? sysenter_do_call+0x12/0x3c
Code: 00 00 00 89 45 ec f7 c7 00 20 00 00 89 55 f0 74 4e f6 86 98 10 00 00 02 74 45 8b 86 8c 10 00 00 8b 9e a8 10 00 00 e8 52 f3 ff ff <0f> a3 03 19 c0 85 c0 75 2b 8b 86 8c 10 00 00 8b 9e a8 10 00 00
EIP: [<c0270c4a>] print_trace_fmt+0x45/0xe7 SS:ESP 0068:d31f3efc
CR2: 0000000000000000
---[ end trace aa9cf38e5ebed9dd ]---
This is because we alloc the iter->started cpumask on tracing_pipe_open but
not on tracing_open.
It hadn't been noticed until now because we need to have ring buffer overruns
to activate the starting of cpu buffer detection.
Also, we need a check to not print the messagge for the first trace on the file.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1238619188-6109-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The wakeup tracing in sched_switch does not stop when a user
disables tracing. This is because the probe_sched_wakeup() is missing
the check to prevent the wakeup from being traced.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
LKML-Reference: <49D1C543.3010307@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Building a kernel with tracing can raise the following warning on
tip/master:
kernel/trace/trace.c:1249: error: implicit declaration of function 'vbin_printf'
We are missing an include to string.h
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1238160130-7437-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix time output bug in 32bits system
ns2usecs() returns 'long', it's incorrect.
(In i386)
...
<idle>-0 [000] 521.442100: _spin_lock <-tick_do_update_jiffies64
<idle>-0 [000] 521.442101: do_timer <-tick_do_update_jiffies64
<idle>-0 [000] 521.442102: update_wall_time <-do_timer
<idle>-0 [000] 521.442102: update_xtime_cache <-update_wall_time
....
(It always print the time less than 2200 seconds besides ...)
Because 'long' is 32bits in i386. ( (1<<31) useconds is about 2200 seconds)
...
<idle>-0 [001] 4154502640.134759: rcu_bh_qsctr_inc <-__do_softirq
<idle>-0 [001] 4154502640.134760: _local_bh_enable <-__do_softirq
<idle>-0 [001] 4154502640.134761: idle_cpu <-irq_exit
...
(very large value)
Because 'long' is a signed type and it is 32bits in i386.
Changes in v2:
return 'unsigned long long' instead of 'cycle_t'
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
LKML-Reference: <49D05D10.4030009@cn.fujitsu.com>
Reported-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Maneesh Soni was getting a crash when running the wakeup tracer.
We debugged it down to the recording of the function with the
CALLER_ADDR2 macro. This is used to get the location of the caller
to schedule.
But the problem comes when schedule is called by assmebly. In the case
that Maneesh had, retint_careful would call schedule. But retint_careful
does not set up a proper frame pointer. CALLER_ADDR2 is defined as
__builtin_return_address(2). This produces the following assembly in
the wakeup tracer code.
mov 0x0(%rbp),%rcx <--- get the frame pointer of the caller
mov %r14d,%r8d
mov 0xf2de8e(%rip),%rdi
mov 0x8(%rcx),%rsi <-- this is __builtin_return_address(1)
mov 0x28(%rdi,%rax,8),%rbx
mov (%rcx),%rax <-- get the frame pointer of the caller's caller
mov %r12,%rcx
mov 0x8(%rax),%rdx <-- this is __builtin_return_address(2)
At the reading of 0x8(%rax) Maneesh's machine would take a fault.
The reason is that retint_careful did not set up the return address
and the content of %rax here was zero.
To verify this, I sent Maneesh a patch to create a frame pointer
in retint_careful. He ran the test again but this time he would take
the same type of fault from sysret_careful. The retint_careful was no
longer an issue, but there are other callers that still have issues.
Instead of adding frame pointers for all callers to schedule (in possibly
all archs), it is much safer to simply not use CALLER_ADDR2. This
loses out on knowing what called schedule, but the function tracer
will help there if needed.
Reported-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge reason: this used to be a tracing/blktrace-v2 devel topic still
cooking during the merge window - has propagated to fixes
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add the ptrace bts context field to task_struct unconditionally.
Initialize the field directly in copy_process().
Remove all the unneeded functionality used to initialize that field.
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144603.292754000@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The hw-branch-tracer uses debug store functions from an on_each_cpu()
context, which is simply wrong since the functions may sleep.
Add _noirq variants for most functions, which may be called with
interrupts disabled.
Separate per-cpu and per-task tracing and allow per-cpu tracing to be
controlled from any cpu.
Make the hw-branch-tracer use the new debug store interface, synchronize
with hotplug cpu event using get/put_online_cpus(), and remove the
unnecessary spinlock.
Make the ptrace bts and the ds selftest code use the new interface.
Defer the ds selftest.
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144555.658136000@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add a function to wait until some other task has been
switched out at least once.
This differs from wait_task_inactive() subtly, in that the
latter will wait until the task has left the CPU.
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Cc: markus.t.metzger@gmail.com
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144549.794157000@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This reverts commit 9cb610d8e3.
This was an impressively stupid patch. Firstly, we reset the SHF_ALLOC
flag lower down in the same function, so the patch was useless. Even
better, find_sec() ignores sections with SHF_ALLOC not set, so
it breaks CONFIG_MODVERSIONS=y with CONFIG_MODULE_FORCE_LOAD=n, which
refuses to load the module since it can't find the __versions section.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The CAP_KILL check in exit_notify() looks just wrong, kill it.
Whatever logic we have to reset ->exit_signal, the malicious user
can bypass it if it execs the setuid application before exiting.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some of the limit constants are used only depending on some complex
configuration dependencies, yet it's not worth making the simple
variables depend on those configuration details. Just mark them as
perhaps not being unused, and avoid the warning.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'kmemtrace-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
kmemtrace: trace kfree() calls with NULL or zero-length objects
kmemtrace: small cleanups
kmemtrace: restore original tracing data binary format, improve ABI
kmemtrace: kmemtrace_alloc() must fill type_id
kmemtrace: use tracepoints
kmemtrace, rcu: don't include unnecessary headers, allow kmemtrace w/ tracepoints
kmemtrace, rcu: fix rcupreempt.c data structure dependencies
kmemtrace, rcu: fix rcu_tree_trace.c data structure dependencies
kmemtrace, rcu: fix linux/rcutree.h and linux/rcuclassic.h dependencies
kmemtrace, mm: fix slab.h dependency problem in mm/failslab.c
kmemtrace, kbuild: fix slab.h dependency problem in lib/decompress_unlzma.c
kmemtrace, kbuild: fix slab.h dependency problem in lib/decompress_bunzip2.c
kmemtrace, kbuild: fix slab.h dependency problem in lib/decompress_inflate.c
kmemtrace, squashfs: fix slab.h dependency problem in squasfs
kmemtrace, befs: fix slab.h dependency problem
kmemtrace, security: fix linux/key.h header file dependencies
kmemtrace, fs: fix linux/fdtable.h header file dependencies
kmemtrace, fs: uninline simple_transaction_set()
kmemtrace, fs, security: move alloc_secdata() and free_secdata() to linux/security.h
* 'audit.b62' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
Audit: remove spaces from audit_log_d_path
audit: audit_set_auditable defined but not used
audit: incorrect ref counting in audit tree tag_chunk
audit: Fix possible return value truncation in audit_get_context()
audit: ignore terminating NUL in AUDIT_USER_TTY messages
Audit: fix handling of 'strings' with NULL characters
make the e->rule.xxx shorter in kernel auditfilter.c
auditsc: fix kernel-doc notation
audit: EXECVE record - removed bogus newline
* 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (413 commits)
tracing, net: fix net tree and tracing tree merge interaction
tracing, powerpc: fix powerpc tree and tracing tree interaction
ring-buffer: do not remove reader page from list on ring buffer free
function-graph: allow unregistering twice
trace: make argument 'mem' of trace_seq_putmem() const
tracing: add missing 'extern' keywords to trace_output.h
tracing: provide trace_seq_reserve()
blktrace: print out BLK_TN_MESSAGE properly
blktrace: extract duplidate code
blktrace: fix memory leak when freeing struct blk_io_trace
blktrace: fix blk_probes_ref chaos
blktrace: make classic output more classic
blktrace: fix off-by-one bug
blktrace: fix the original blktrace
blktrace: fix a race when creating blk_tree_root in debugfs
blktrace: fix timestamp in binary output
tracing, Text Edit Lock: cleanup
tracing: filter fix for TRACE_EVENT_FORMAT events
ftrace: Using FTRACE_WARN_ON() to check "freed record" in ftrace_release()
x86: kretprobe-booster interrupt emulation code fix
...
Fix up trivial conflicts in
arch/parisc/include/asm/ftrace.h
include/linux/memory.h
kernel/extable.c
kernel/module.c
audit_log_d_path had spaces in the strings which would be emitted on the
error paths. This patch simply replaces those spaces with an _ or removes
the needless spaces entirely.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
after 0590b9335a audit_set_auditable() is now only
used by the audit tree code. If CONFIG_AUDIT_TREE is unset it will be defined
but unused. This patch simply moves the function inside a CONFIG_AUDIT_TREE
block.
cc1: warnings being treated as errors
/home/acme_unencrypted/git/linux-2.6-tip/kernel/auditsc.c:745: error: ‘audit_set_auditable’ defined but not used
make[2]: *** [kernel/auditsc.o] Error 1
make[1]: *** [kernel] Error 2
make[1]: *** Waiting for unfinished jobs....
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
tag_chunk has bad exit paths in which the inotify ref counting is wrong.
At the top of the function we found &old_watch using inotify_find_watch().
inotify_find_watch takes a reference to the watch. This is never dropped
on an error path.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The audit subsystem treats syscall return codes as type long, unfortunately
the audit_get_context() function mistakenly converts the return code to an
int type in the parameters which could cause problems on systems where the
sizeof(int) != sizeof(long).
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
AUDIT_USER_TTY, like all other messages sent from user-space, is sent
NUL-terminated. Unlike other user-space audit messages, which come only
from trusted sources, AUDIT_USER_TTY messages are processed using
audit_log_n_untrustedstring().
This patch modifies AUDIT_USER_TTY handling to ignore the trailing NUL
and use the "quoted_string" representation of the message if possible.
Signed-off-by: Miloslav Trmac <mitr@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
currently audit_log_n_untrustedstring() uses audit_string_contains_control()
to check if the 'string' has any control characters. If the 'string' has an
embedded NULL audit_string_contains_control() will return that the data has
no control characters and will then pass the string to audit_log_n_string
with the total length, not the length up to the first NULL.
audit_log_n_string() does a memcpy of the entire length and so the actual
audit record emitted may then contain a NULL and then whatever random memory
is after the NULL.
Since we want to log the entire octet stream (if we can't trust the data
to be a string we can't trust that a NULL isn't actually a part of it)
we should just consider NULL as a control character. If the caller is
certain they want to stop at the first NULL they should be using
audit_log_untrustedstring.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
make the e->rule.xxx shorter in kernel/auditfilter.c
--
---------------------------------
Zhenwen Xu - Open and Free
Home Page: http://zhwen.org
My Studio: http://dim4.cn
>From 99692dc640b278f1cb1a15646ce42f22e89c0f77 Mon Sep 17 00:00:00 2001
From: Zhenwen Xu <Helight.Xu@gmail.com>
Date: Thu, 12 Mar 2009 22:04:59 +0800
Subject: [PATCH] make the e->rule.xxx shorter in kernel/auditfilter.c
Signed-off-by: Zhenwen Xu <Helight.Xu@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Fix auditsc kernel-doc notation:
Warning(linux-2.6.28-git7//kernel/auditsc.c:2156): No description found for parameter 'attr'
Warning(linux-2.6.28-git7//kernel/auditsc.c:2156): Excess function parameter 'u_attr' description in '__audit_mq_open'
Warning(linux-2.6.28-git7//kernel/auditsc.c:2204): No description found for parameter 'notification'
Warning(linux-2.6.28-git7//kernel/auditsc.c:2204): Excess function parameter 'u_notification' description in '__audit_mq_notify'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
(updated)
Added hunk that changes the comment, the rest is the same.
EXECVE records contain a newline after every argument. auditd converts
"\n" to " " so you cannot see newlines even in raw logs, but they're
there nevertheless. If you're not using auditd, you need to work round
them. These '\n' chars are can be easily replaced by spaces when
creating record in kernel. Note there is no need for trailing '\n' in
an audit record.
record before this patch:
"type=EXECVE msg=audit(1231421801.566:31): argc=4 a0=\"./test\"\na1=\"a\"\na2=\"b\"\na3=\"c\"\n"
record after this patch:
"type=EXECVE msg=audit(1231421801.566:31): argc=4 a0=\"./test\" a1=\"a\" a2=\"b\" a3=\"c\""
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask: (36 commits)
cpumask: remove cpumask allocation from idle_balance, fix
numa, cpumask: move numa_node_id default implementation to topology.h, fix
cpumask: remove cpumask allocation from idle_balance
x86: cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus
x86: cpumask: update 32-bit APM not to mug current->cpus_allowed
x86: microcode: cleanup
x86: cpumask: use work_on_cpu in arch/x86/kernel/microcode_core.c
cpumask: fix CONFIG_CPUMASK_OFFSTACK=y cpu hotunplug crash
numa, cpumask: move numa_node_id default implementation to topology.h
cpumask: convert node_to_cpumask_map[] to cpumask_var_t
cpumask: remove x86 cpumask_t uses.
cpumask: use cpumask_var_t in uv_flush_tlb_others.
cpumask: remove cpumask_t assignment from vector_allocation_domain()
cpumask: make Xen use the new operators.
cpumask: clean up summit's send_IPI functions
cpumask: use new cpumask functions throughout x86
x86: unify cpu_callin_mask/cpu_callout_mask/cpu_initialized_mask/cpu_sibling_setup_mask
cpumask: convert struct cpuinfo_x86's llc_shared_map to cpumask_var_t
cpumask: convert node_to_cpumask_map[] to cpumask_var_t
x86: unify 32 and 64-bit node_to_cpumask_map
...
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-module-and-param:
module: use strstarts()
strstarts: helper function for !strncmp(str, prefix, strlen(prefix))
arm: allow usage of string functions in linux/string.h
module: don't use stop_machine on module load
module: create a request_module_nowait()
module: include other structures in module version check
module: remove the SHF_ALLOC flag on the __versions section.
module: clarify the force-loading taint message.
module: Export symbols needed for Ksplice
Ksplice: Add functions for walking kallsyms symbols
module: remove module_text_address()
module: __module_address
module: Make find_symbol return a struct kernel_symbol
kernel/module.c: fix an unused goto label
param: fix charp parameters set via sysfs
Fix trivial conflicts in kernel/extable.c manually.
* 'printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
printk: correct the behavior of printk_timed_ratelimit()
vsprintf: unify the format decoding layer for its 3 users, cleanup
fix regression from "vsprintf: unify the format decoding layer for its 3 users"
vsprintf: fix bug in negative value printing
vsprintf: unify the format decoding layer for its 3 users
vsprintf: add binary printf
printk: introduce printk_once()
Fix trivial conflicts (printk_once vs log_buf_kexec_setup() added near
each other) in include/linux/kernel.h.
* 'stacktrace-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
symbols, stacktrace: look up init symbols after module symbols
* 'rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
rcu: rcu_barrier VS cpu_hotplug: Ensure callbacks in dead cpu are migrated to online cpu
* 'ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
s390: remove arch specific smp_send_stop()
panic: clean up kernel/panic.c
panic, smp: provide smp_send_stop() wrapper on UP too
panic: decrease oops_in_progress only after having done the panic
generic-ipi: eliminate WARN_ON()s during oops/panic
generic-ipi: cleanups
generic-ipi: remove CSD_FLAG_WAIT
generic-ipi: remove kmalloc()
generic IPI: simplify barriers and locking
* 'locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
locking: rename trace_softirq_[enter|exit] => lockdep_softirq_[enter|exit]
lockdep: remove duplicate CONFIG_DEBUG_LOCKDEP definitions
lockdep: require framepointers for x86
lockdep: remove extra "irq" string
lockdep: fix incorrect state name
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (28 commits)
trivial: Update my email address
trivial: NULL noise: drivers/mtd/tests/mtd_*test.c
trivial: NULL noise: drivers/media/dvb/frontends/drx397xD_fw.h
trivial: Fix misspelling of "Celsius".
trivial: remove unused variable 'path' in alloc_file()
trivial: fix a pdlfush -> pdflush typo in comment
trivial: jbd header comment typo fix for JBD_PARANOID_IOFAIL
trivial: wusb: Storage class should be before const qualifier
trivial: drivers/char/bsr.c: Storage class should be before const qualifier
trivial: h8300: Storage class should be before const qualifier
trivial: fix where cgroup documentation is not correctly referred to
trivial: Give the right path in Documentation example
trivial: MTD: remove EOL from MODULE_DESCRIPTION
trivial: Fix typo in bio_split()'s documentation
trivial: PWM: fix of #endif comment
trivial: fix typos/grammar errors in Kconfig texts
trivial: Fix misspelling of firmware
trivial: cgroups: documentation typo and spelling corrections
trivial: Update contact info for Jochen Hein
trivial: fix typo "resgister" -> "register"
...
Need to free the old cpumask for affinity and pending_mask.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <49D18FF0.50707@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Document the slow work thread pool.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
Make the slow work pool configurable through /proc/sys/kernel/slow-work.
(*) /proc/sys/kernel/slow-work/min-threads
The minimum number of threads that should be in the pool as long as it is
in use. This may be anywhere between 2 and max-threads.
(*) /proc/sys/kernel/slow-work/max-threads
The maximum number of threads that should in the pool. This may be
anywhere between min-threads and 255 or NR_CPUS * 2, whichever is greater.
(*) /proc/sys/kernel/slow-work/vslow-percentage
The percentage of active threads in the pool that may be used to execute
very slow work items. This may be between 1 and 99. The resultant number
is bounded to between 1 and one fewer than the number of active threads.
This ensures there is always at least one thread that can process very
slow work items, and always at least one thread that won't.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
Make the slow-work thread pool actually dynamic in the number of threads it
contains. With this patch, it will both create additional threads when it has
extra work to do, and cull excess threads that aren't doing anything.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
Create a dynamically sized pool of threads for doing very slow work items, such
as invoking mkdir() or rmdir() - things that may take a long time and may
sleep, holding mutexes/semaphores and hogging a thread, and are thus unsuitable
for workqueues.
The number of threads is always at least a settable minimum, but more are
started when there's more work to do, up to a limit. Because of the nature of
the load, it's not suitable for a 1-thread-per-CPU type pool. A system with
one CPU may well want several threads.
This is used by FS-Cache to do slow caching operations in the background, such
as looking up, creating or deleting cache objects.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
Impact: output all of packet commands - not just the first 4 / 8 bytes
Since commit d7e3c3249e ("block: add
large command support"), struct request->cmd has been changed from
unsinged char cmd[BLK_MAX_CDB] to unsigned char *cmd.
v1 -> v2: by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
- make sure rq->cmd_len is always intialized, and then we can use
rq->cmd_len instead of BLK_MAX_CDB.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
LKML-Reference: <49D4507E.2060602@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix corrupted blkparse output
Make sure messages from user space are NUL-terminated strings,
otherwise we could dump random memory to the block trace file.
Additionally, I've limited the message to BLK_TN_MAX_MSG-1
characters, because the last character would be stripped by
vscnprintf anyway.
Signed-off-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "Alan D. Brunelle" <alan.brunelle@hp.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20090403122714.GT5178@kernel.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When kmemtrace was ported to ftrace, the marker strings were taken as
an indication of how the traced data was being exposed to the userspace.
However, the actual format had been binary, not text.
This restores the original binary format, while also adding an origin CPU
field (since ftrace doesn't expose the data per-CPU to userspace), and
re-adding the timestamp field. It also drops arch-independent field
sizing where it didn't make sense, so pointers won't always be 64 bits
wide like they used to.
Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
LKML-Reference: <161be9ca8a27b432c4a6ab79f47788c4521652ae.1237813499.git.eduard.munteanu@linux360.ro>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix trace output
kmemtrace_alloc() was not filling type_id, which allowed garbage to make
it into tracing data.
Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
LKML-Reference: <284dba2732a144849d5aa82258fe0de2ad8dcb0b.1237813499.git.eduard.munteanu@linux360.ro>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kmemtrace now uses tracepoints instead of markers. We no longer need to
use format specifiers to pass arguments.
Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
[ folded: Use the new TP_PROTO and TP_ARGS to fix the build. ]
[ folded: fix build when CONFIG_KMEMTRACE is disabled. ]
[ folded: define tracepoints when CONFIG_TRACEPOINTS is enabled. ]
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <ae61c0f37156db8ec8dc0d5778018edde60a92e3.1237813499.git.eduard.munteanu@linux360.ro>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
We want to remove percpu.h from rcupreempt.h, but if we do that
the percpu primitives there wont build anymore. Move them to the
.c file instead.
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: paulmck@linux.vnet.ibm.com
LKML-Reference: <1237898630.25315.83.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: cleanup
We want to remove rcutree internals from the public rcutree.h file for
upcoming kmemtrace changes - but kernel/rcutree_trace.c depends on them.
Introduce kernel/rcutree.h for internal definitions. (Probably all
the other data types from include/linux/rcutree.h could be
moved here too - except rcu_data.)
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: paulmck@linux.vnet.ibm.com
LKML-Reference: <1237898630.25315.83.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: build fix for all non-x86 architectures
We want to remove percpu.h from rcuclassic.h/rcutree.h (for upcoming
kmemtrace changes) but that would break the DECLARE_PER_CPU based
declarations in these files.
Move the quiescent counter management functions to their respective
RCU implementation .c files - they were slightly above the inlining
limit anyway.
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: paulmck@linux.vnet.ibm.com
LKML-Reference: <1237898630.25315.83.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
Remove two unneeded exports and make two symbols static in fs/mpage.c
Cleanup after commit 585d3bc06f
Trim includes of fdtable.h
Don't crap into descriptor table in binfmt_som
Trim includes in binfmt_elf
Don't mess with descriptor table in load_elf_binary()
Get rid of indirect include of fs_struct.h
New helper - current_umask()
check_unsafe_exec() doesn't care about signal handlers sharing
New locking/refcounting for fs_struct
Take fs_struct handling to new file (fs/fs_struct.c)
Get rid of bumping fs_struct refcount in pivot_root(2)
Kill unsharing fs_struct in __set_personality()
Pass the original flags to rwlock arch-code, so that it can re-enable
interrupts if implemented for that architecture.
Initially, make __raw_read_lock_flags and __raw_write_lock_flags stubs
which just do the same thing as non-flags variants.
Signed-off-by: Petr Tesarik <ptesarik@suse.cz>
Signed-off-by: Robin Holt <holt@sgi.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <linux-arch@vger.kernel.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SGI has observed that on large systems, interrupts are not serviced for a
long period of time when waiting for a rwlock. The following patch series
re-enables irqs while waiting for the lock, resembling the code which is
already there for spinlocks.
I only made the ia64 version, because the patch adds some overhead to the
fast path. I assume there is currently no demand to have this for other
architectures, because the systems are not so large. Of course, the
possibility to implement raw_{read|write}_lock_flags for any architecture
is still there.
This patch:
The new macro LOCK_CONTENDED_FLAGS expands to the correct implementation
depending on the config options, so that IRQ's are re-enabled when
possible, but they remain disabled if CONFIG_LOCKDEP is set.
Signed-off-by: Petr Tesarik <ptesarik@suse.cz>
Signed-off-by: Robin Holt <holt@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix possible loss/corruption of produced subbufs in
relay_subbufs_consumed().
When buf->subbufs_produced wraps around after UINT_MAX and
buf->subbufs_consumed is still < UINT_MAX, the condition
if (buf->subbufs_consumed > buf->subbufs_produced)
will be true even for certain valid values of subbufs_consumed. This may
lead to loss or corruption of produced subbufs.
Signed-off-by: Aravind Srinivasan <raa.aars@gmail.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Tom Zanussi <zanussi@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The vmcoreinfo_data[] array is not used outside of kernel/kexec.c, and
can therefore become static. This patch adds the relevant keyword to the
definition of the array.
Noticed by sparse.
Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@movial.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It would be nice to be able to extract the dmesg log from a vmcore file
without needing to keep the debug symbols for the running kernel handy all
the time. We have a facility to do this in /proc/vmcore. This patch adds
the log_buf and log_end symbols to the vmcoreinfo area so that tools (like
makedumpfile) can easily extract the dmesg logs from a vmcore image.
[akpm@linux-foundation.org: several fixes and cleanups]
[akpm@linux-foundation.org: fix unused log_buf_kexec_setup()]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Simon Horman <horms@verge.net.au>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We are wasting 2 words in signal_struct without any reason to implement
task_pgrp_nr() and task_session_nr().
task_session_nr() has no callers since
2e2ba22ea4, we can remove it.
task_pgrp_nr() is still (I believe wrongly) used in fs/autofsX and
fs/coda.
This patch reimplements task_pgrp_nr() via task_pgrp_nr_ns(), and kills
__pgrp/__session and the related helpers.
The change in drivers/char/tty_io.c is cosmetic, but hopefully makes sense
anyway.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Alan Cox <number6@the-village.bc.nu> [tty parts]
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Inho, the safety rules for vnr/nr_ns helpers are horrible and buggy.
task_pid_nr_ns(task) needs rcu/tasklist depending on task == current.
As for "special" pids, vnr/nr_ns helpers always need rcu. However, if
task != current, they are unsafe even under rcu lock, we can't trust
task->group_leader without the special checks.
And almost every helper has a callsite which needs a fix.
Also, it is a bit annoying that the implementations of, say,
task_pgrp_vnr() and task_pgrp_nr_ns() are not "symmetrical".
This patch introduces the new helper, __task_pid_nr_ns(), which is always
safe to use, and turns all other helpers into the trivial wrappers.
After this I'll send another patch which converts task_tgid_xxx() as well,
they're are a bit special.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Louis Rilling <Louis.Rilling@kerlabs.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sys_wait4() does get_pid(task_pgrp(current)), this is not safe. We can
add rcu lock/unlock around, but we already have get_task_pid() which can
be improved to handle the special pids in more reliable manner.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Louis Rilling <Louis.Rilling@kerlabs.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As pointed out by Cedric Le Goater (in response to Alexey's original
comment wrt mqns), ipc_sysctl.c and utsname_sysctl.c are using
CONFIG_PROC_FS, not CONFIG_PROC_SYSCTL, to determine whether to define
the proc_handlers. Change that.
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Acked-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1) lockdep will complain when run_workqueue() performs recursion.
2) The recursive implementation of run_workqueue() means that
flush_workqueue() and its documentation are inconsistent. This may
hide deadlocks and other bugs.
3) The recursion in run_workqueue() will poison cwq->current_work, but
flush_work() and __cancel_work_timer(), etcetera need a reliable
cwq->current_work.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This bug is ancient too. ptrace_untrace() must not resume the task
if the group stop in progress, we should set TASK_STOPPED instead.
Unfortunately, we still have problems here:
- if the process/thread was traced, SIGNAL_STOP_STOPPED
does not necessary means this thread group is stopped.
- ptrace breaks the bookkeeping of ->group_stop_count.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Another ancient bug. Consider this trivial test-case,
int main(void)
{
int pid = fork();
if (pid) {
ptrace(PTRACE_ATTACH, pid, NULL, NULL);
wait(NULL);
ptrace(PTRACE_DETACH, pid, NULL, NULL);
} else {
pause();
printf("WE HAVE A KERNEL BUG!!!\n");
}
return 0;
}
the child must not "escape" for sys_pause(), but it can and this was seen
in practice.
This is because ptrace_detach does:
if (!child->exit_state)
wake_up_process(child);
this wakeup can happen after this child has already restarted sys_pause(),
because it gets another wakeup from ptrace_untrace().
With or without this patch, perhaps sys_pause() needs a fix. But this
wakeup also breaks the SIGNAL_STOP_STOPPED logic in ptrace_untrace().
Remove this wakeup. The caller saw this task in TASK_TRACED state, and
unless it was SIGKILL'ed in between __ptrace_unlink()->ptrace_untrace()
should handle this case correctly. If it was SIGKILL'ed, we don't need to
wakup the dying tracee too.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
By discussion with Roland.
- Use ->sibling instead of ->ptrace_entry to chain the need to be
release_task'd childs. Nobody else can use ->sibling, this task
is EXIT_DEAD and nobody can find it on its own list.
- rename ptrace_dead to dead_childs.
- Now that we don't have the "parallel" untrace code, change back
reparent_thread() to return void, pass dead_childs as an argument.
Actually, I don't understand why do we notify /sbin/init when we
reparent a zombie, probably it is better to reap it unconditionally.
[akpm@linux-foundation.org: s/childs/children/]
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Metzger, Markus T" <markus.t.metzger@intel.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
By discussion with Roland.
- Rename ptrace_exit() to exit_ptrace(), and change it to do all the
necessary work with ->ptraced list by its own.
- Move this code from exit.c to ptrace.c
- Update the comment in ptrace_detach() to explain the rechecking of
the child->ptrace.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Metzger, Markus T" <markus.t.metzger@intel.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If /sbin/init ignores SIGCHLD and we re-parent a zombie, it is leaked.
reparent_thread() does do_notify_parent() which sets ->exit_signal = -1 in
this case. This means that nobody except us can reap it, the detached
task is not visible to do_wait().
Change reparent_thread() to return a boolean (like __pthread_detach) to
indicate that the thread is dead and must be released. Also change
forget_original_parent() to add the child to ptrace_dead list in this
case.
The naming becomes insane, the next patch does the cleanup.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
reparent_thread() uses ptrace_reparented() to check whether this thread is
ptraced, in that case we should not notify the new parent.
But ptrace_reparented() is not exactly correct when the reparented thread
is traced by /sbin/init, because forget_original_parent() has already
changed ->real_parent.
Currently, the only problem is the false notification. But with the next
patch the kernel crash in this (yes, pathological) case.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If task_detached(p) == T, then either
a) p is not the main thread, we will find the group leader on the
->children list.
or
b) p is the group leader but its ->exit_state = EXIT_DEAD. This
can only happen when the last sub-thread has died, but in that case
that thread has already called kill_orphaned_pgrp() from
exit_notify().
In both cases kill_orphaned_pgrp() looks bogus.
Move the task_detached() check up and simplify the code, this is also
right from the "common sense" pov: we should do nothing with the detached
childs, except move them to the new parent's ->children list.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When ptrace_detach() takes tasklist, the tracee can be SIGKILL'ed. If it
has already passed exit_notify() we can leak a zombie, because a) ptracing
disables the auto-reaping logic, and b) ->real_parent was not notified
about the child's death.
ptrace_detach() should follow the ptrace_exit's logic, change the code
accordingly.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Tested-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
No functional changes, preparation for the next patch.
Move the "should we release this child" logic into the separate handler,
__ptrace_detach().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ignoring_children() takes parent->sighand->siglock and checks
k_sigaction[SIGCHLD] atomically. But this buys nothing, we can't get the
"really" wrong result even if we race with sigaction(SIGCHLD). If we read
the "stale" sa_handler/sa_flags we can pretend it was changed right after
the check.
Remove spin_lock(->siglock), and kill "int ign" which caches the result of
ignoring_children() which becomes rather trivial.
Perhaps it makes sense to export this helper, do_notify_parent() can use
it too.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move the code from __ptrace_detach() to its single caller and kill this
helper.
Also, fix the ->exit_state check, we shouldn't wake up EXIT_DEAD tasks.
Actually, I think task_is_stopped_or_traced() makes more sense, but this
needs another patch.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When sending a signal to a descendant namespace, set ->si_pid to 0 since
the sender does not have a pid in the receiver's namespace.
Note:
- If rt_sigqueueinfo() sets si_code to SI_USER when sending a
signal across a pid namespace boundary, the value in ->si_pid
will be cleared to 0.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Normally SIG_DFL signals to global and container-init are dropped early.
But if a signal is blocked when it is posted, we cannot drop the signal
since the receiver may install a handler before unblocking the signal.
Once this signal is queued however, the receiver container-init has no way
of knowing if the signal was sent from an ancestor or descendant
namespace. This patch ensures that contianer-init drops all SIG_DFL
signals in get_signal_to_deliver() except SIGKILL/SIGSTOP.
If SIGSTOP/SIGKILL originate from a descendant of container-init they are
never queued (i.e dropped in sig_ignored() in an earler patch).
If SIGSTOP/SIGKILL originate from parent namespace, the signal is queued
and container-init processes the signal.
IOW, if get_signal_to_deliver() sees a sig_kernel_only() signal for global
or container-init, the signal must have been generated internally or must
have come from an ancestor ns and we process the signal.
Further, the signal_group_exit() check was needed to cover the case of a
multi-threaded init sending SIGKILL to other threads when doing an exit()
or exec(). But since the new sig_kernel_only() check covers the SIGKILL,
the signal_group_exit() check is no longer needed and can be removed.
Finally, now that we have all pieces in place, set SIGNAL_UNKILLABLE for
container-inits.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
send_signal() assumes that signals with SEND_SIG_PRIV are generated from
within the same namespace. So any nested container-init processes become
immune to the SIGKILL generated by kill_proc_info() in
zap_pid_ns_processes().
Use force_sig() in zap_pid_ns_processes() instead - force_sig() clears the
SIGNAL_UNKILLABLE flag ensuring the signal is processed by
container-inits.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Drop early any SIG_DFL or SIG_IGN signals to container-init from within
the same container. But queue SIGSTOP and SIGKILL to the container-init
if they are from an ancestor container.
Blocked, fatal signals (i.e when SIG_DFL is to terminate) from within the
container can still terminate the container-init. That will be addressed
in the next patch.
Note: To be bisect-safe, SIGNAL_UNKILLABLE will be set for container-inits
in a follow-on patch. Until then, this patch is just a preparatory
step.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
send_signal() (or its helper) needs to determine the pid namespace of the
sender. But a signal sent via kill_pid_info_as_uid() comes from within
the kernel and send_signal() does not need to determine the pid namespace
of the sender. So define a helper for send_signal() which takes an
additional parameter, 'from_ancestor_ns' and have kill_pid_info_as_uid()
use that helper directly.
The 'from_ancestor_ns' parameter will be used in a follow-on patch.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(This is a modified version of the patch submitted by Oleg Nesterov
http://lkml.org/lkml/2008/11/18/249 and tries to address comments that
came up in that discussion)
init ignores the SIG_DFL signals but we queue them anyway, including
SIGKILL. This is mostly OK, the signal will be dropped silently when
dequeued, but the pending SIGKILL has 2 bad implications:
- it implies fatal_signal_pending(), so we confuse things
like wait_for_completion_killable/lock_page_killable.
- for the sub-namespace inits, the pending SIGKILL can
mask (legacy_queue) the subsequent SIGKILL from the
parent namespace which must kill cinit reliably.
(preparation, cinits don't have SIGNAL_UNKILLABLE yet)
The patch can't help when init is ptraced, but ptracing of init is not
"safe" anyway.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Container-init must behave like global-init to processes within the
container and hence it must be immune to unhandled fatal signals from
within the container (i.e SIG_DFL signals that terminate the process).
But the same container-init must behave like a normal process to processes
in ancestor namespaces and so if it receives the same fatal signal from a
process in ancestor namespace, the signal must be processed.
Implementing these semantics requires that send_signal() determine pid
namespace of the sender but since signals can originate from workqueues/
interrupt-handlers, determining pid namespace of sender may not always be
possible or safe.
This patchset implements the design/simplified semantics suggested by
Oleg Nesterov. The simplified semantics for container-init are:
- container-init must never be terminated by a signal from a
descendant process.
- container-init must never be immune to SIGKILL from an ancestor
namespace (so a process in parent namespace must always be able
to terminate a descendant container).
- container-init may be immune to unhandled fatal signals (like
SIGUSR1) even if they are from ancestor namespace. SIGKILL/SIGSTOP
are the only reliable signals to a container-init from ancestor
namespace.
This patch:
Based on an earlier patch submitted by Oleg Nesterov and comments from
Roland McGrath (http://lkml.org/lkml/2008/11/19/258).
The handler parameter is currently unused in the tracehook functions.
Besides, the tracehook functions are called with siglock held, so the
functions can check the handler if they later need to.
Removing the parameter simiplifies changes to sig_ignored() in a follow-on
patch.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
do_wait(WSTOPPED) assumes that p->state must be == TASK_STOPPED, this is
not true if the leader is already dead. Check SIGNAL_STOP_STOPPED instead
and use signal->group_exit_code.
Trivial test-case:
void *tfunc(void *arg)
{
pause();
return NULL;
}
int main(void)
{
pthread_t thr;
pthread_create(&thr, NULL, tfunc, NULL);
pthread_exit(NULL);
return 0;
}
It doesn't react to ^Z (and then to ^C or ^\). The task is stopped, but
bash can't see this.
The bug is very old, and it was reported multiple times. This patch was sent
more than a year ago (http://marc.info/?t=119713920000003) but it was ignored.
This change also fixes other oddities (but not all) in this area. For
example, before this patch:
$ sleep 100
^Z
[1]+ Stopped sleep 100
$ strace -p `pidof sleep`
Process 11442 attached - interrupt to quit
strace hangs in do_wait(), because ->exit_code was already consumed by
bash. After this patch, strace happily proceeds:
--- SIGTSTP (Stopped) @ 0 (0) ---
restart_syscall(<... resuming interrupted call ...>
To me, this looks much more "natural" and correct.
Another example. Let's suppose we have the main thread M and sub-thread
T, the process is stopped, and its parent did wait(WSTOPPED). Now we can
ptrace T but not M. This looks at least strange to me.
Imho, do_wait() should not confuse the per-thread ptrace stops with the
per-process job control stops.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Kaz Kylheku <kkylheku@gmail.com>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kthreads that have the PF_THREAD_BOUND bit set in their flags are bound to a
specific cpu. Thus, their set of allowed cpus shall not change.
This patch prevents such threads from attaching to non-root cpusets. They do
not have mempolicies that restrict them to a subset of system nodes and, since
their cpumask may never change, they cannot use any of the features of
cpusets.
The tasks will forever be a member of the root cpuset and will be returned
when listing the tasks attached to that cpuset.
Cc: Paul Menage <menage@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allow cpusets to be configured/built on non-SMP systems
Currently it's impossible to build cpusets under UML on x86-64, since
cpusets depends on SMP and x86-64 UML doesn't support SMP.
There's code in cpusets that doesn't depend on SMP. This patch surrounds
the minimum amount of cpusets code with #ifdef CONFIG_SMP in order to
allow cpusets to build/run on UP systems (for testing purposes under UML).
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Paul Menage <menage@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The cpuset_zone_allowed() variants are actually only a function of the
zone's node.
Cc: Paul Menage <menage@google.com>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When writing to cpuset.mems, cpuset has to update its mems_allowed before
calling update_tasks_nodemask(), but this function might return -ENOMEM.
To avoid this rare case, we allocate the memory before changing
mems_allowed, and then pass to update_tasks_nodemask(). Similar to what
update_cpumask() does.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch uses cgroup_scan_tasks() to rebind tasks' vmas to new cpuset's
mems_allowed.
Not only simplify the code largely, but also avoid allocating an array to
hold mm pointers of all the tasks in the cpuset. This array can be big
(size > PAGESIZE) if we have lots of tasks in that cpuset, thus has a
chance to fail the allocation when under memory stress.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change to cpuset->cpus_allowed and cpuset->mems_allowed should be protected
by callback_mutex, otherwise the reader may read wrong cpus/mems. This is
cpuset's lock rule.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch tries to fix OOM Killer problems caused by hierarchy.
Now, memcg itself has OOM KILL function (in oom_kill.c) and tries to
kill a task in memcg.
But, when hierarchy is used, it's broken and correct task cannot
be killed. For example, in following cgroup
/groupA/ hierarchy=1, limit=1G,
01 nolimit
02 nolimit
All tasks' memory usage under /groupA, /groupA/01, groupA/02 is limited to
groupA's 1Gbytes but OOM Killer just kills tasks in groupA.
This patch provides makes the bad process be selected from all tasks
under hierarchy. BTW, currently, oom_jiffies is updated against groupA
in above case. oom_jiffies of tree should be updated.
To see how oom_jiffies is used, please check mem_cgroup_oom_called()
callers.
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: const fix]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since we are in cgroup write handler, so the cgrp is valid, so we don't
have to hold cgroup_mutex when calling cgroup_task_count(). One similar
example is in cgroup_tasks_open().
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remount can fail in either case:
- wrong mount options is specified, or option 'noprefix' is changed.
- a to-be-added subsys is already mounted/active.
When using remount to change 'release_agent', for the above former failure
case, remount will return errno with release_agent unchanged, but for the
latter case, remount will return EBUSY with relase_agent changed, which is
unexpected I think:
# mount -t cgroup -o cpu xxx /cgrp1
# mount -t cgroup -o cpuset,release_agent=agent1 yyy /cgrp2
# cat /cgrp2/release_agent
agent1
# mount -t cgroup -o remount,cpuset,noprefix,release_agent=agent2 yyy /cgrp2
mount: /cgrp2 not mounted already, or bad option
# cat /cgrp2/release_agent
agent1 <-- ok
# mount -t cgroup -o remount,cpu,cpuset,release_agent=agent2 yyy /cgrp2
mount: /cgrp2 is busy
# cat /cgrp2/release_agent
agent2 <-- unexpected!
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have some read-only files and write-only files, but currently they are
all set to 0644, which is counter-intuitive and cause trouble for some
cgroup tools like libcgroup.
This patch adds 'mode' to struct cftype to allow cgroup subsys to set it's
own files' file mode, and for the most cases cft->mode can be default to 0
and cgroup will figure out proper mode.
Acked-by: Paul Menage <menage@google.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In following situation, with memory subsystem,
/groupA use_hierarchy==1
/01 some tasks
/02 some tasks
/03 some tasks
/04 empty
When tasks under 01/02/03 hit limit on /groupA, hierarchical reclaim
is triggered and the kernel walks tree under groupA. In this case,
rmdir /groupA/04 fails with -EBUSY frequently because of temporal
refcnt from the kernel.
In general. cgroup can be rmdir'd if there are no children groups and
no tasks. Frequent fails of rmdir() is not useful to users.
(And the reason for -EBUSY is unknown to users.....in most cases)
This patch tries to modify above behavior, by
- retries if css_refcnt is got by someone.
- add "return value" to pre_destroy() and allows subsystem to
say "we're really busy!"
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch for Per-CSS(Cgroup Subsys State) ID and private hierarchy code.
This patch attaches unique ID to each css and provides following.
- css_lookup(subsys, id)
returns pointer to struct cgroup_subysys_state of id.
- css_get_next(subsys, id, rootid, depth, foundid)
returns the next css under "root" by scanning
When cgroup_subsys->use_id is set, an id for css is maintained.
The cgroup framework only parepares
- css_id of root css for subsys
- id is automatically attached at creation of css.
- id is *not* freed automatically. Because the cgroup framework
don't know lifetime of cgroup_subsys_state.
free_css_id() function is provided. This must be called by subsys.
There are several reasons to develop this.
- Saving space .... For example, memcg's swap_cgroup is array of
pointers to cgroup. But it is not necessary to be very fast.
By replacing pointers(8bytes per ent) to ID (2byes per ent), we can
reduce much amount of memory usage.
- Scanning without lock.
CSS_ID provides "scan id under this ROOT" function. By this, scanning
css under root can be written without locks.
ex)
do {
rcu_read_lock();
next = cgroup_get_next(subsys, id, root, &found);
/* check sanity of next here */
css_tryget();
rcu_read_unlock();
id = found + 1
} while(...)
Characteristics:
- Each css has unique ID under subsys.
- Lifetime of ID is controlled by subsys.
- css ID contains "ID" and "Depth in hierarchy" and stack of hierarchy
- Allowed ID is 1-65535, ID 0 is UNUSED ID.
Design Choices:
- scan-by-ID v.s. scan-by-tree-walk.
As /proc's pid scan does, scan-by-ID is robust when scanning is done
by following kind of routine.
scan -> rest a while(release a lock) -> conitunue from interrupted
memcg's hierarchical reclaim does this.
- When subsys->use_id is set, # of css in the system is limited to
65535.
[bharata@linux.vnet.ibm.com: remove rcu_read_lock() from css_get_next()]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ns_proxy cgroup allows moving processes to child cgroups only one
level deep at a time. This commit relaxes this restriction and makes it
possible to attach tasks directly to grandchild cgroups, e.g.:
($pid is in the root cgroup)
echo $pid > /cgroup/CG1/CG2/tasks
Previously this operation would fail with -EPERM and would have to be
performed as two steps:
echo $pid > /cgroup/CG1/tasks
echo $pid > /cgroup/CG1/CG2/tasks
Also, the target cgroup no longer needs to be empty to move a task there.
Signed-off-by: Grzegorz Nosek <root@localdomain.pl>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix a number of issues with the per-MM VMA patch:
(1) Make mmap_pages_allocated an atomic_long_t, just in case this is used on
a NOMMU system with more than 2G pages. Makes no difference on a 32-bit
system.
(2) Report vma->vm_pgoff * PAGE_SIZE as a 64-bit value, not a 32-bit value,
lest it overflow.
(3) Move the allocation of the vm_area_struct slab back for fork.c.
(4) Use KMEM_CACHE() for both vm_area_struct and vm_region slabs.
(5) Use BUG_ON() rather than if () BUG().
(6) Make the default validate_nommu_regions() a static inline rather than a
#define.
(7) Make free_page_series()'s objection to pages with a refcount != 1 more
informative.
(8) Adjust the __put_nommu_region() banner comment to indicate that the
semaphore must be held for writing.
(9) Limit the number of warnings about munmaps of non-mmapped regions.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We've tripped over the futex_requeue drop_count refering to key2
instead of key1. The code is actually correct, but is non-intuitive.
This patch adds an explicit comment explaining the requeue.
Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
