linux/kernel
Andi Kleen d72b37513c Remove stop_machine during module load v2
Remove stop_machine during module load v2

module loading currently does a stop_machine on each module load to insert
the module into the global module lists.  Especially on larger systems this
can be quite expensive.

It does that to handle concurrent lock lessmodule list readers
like kallsyms.

I don't think stop_machine() is actually needed to insert something
into a list though. There are no concurrent writers because the
module mutex is taken. And the RCU list functions know how to insert
a node into a list with the right memory ordering so that concurrent
readers don't go off into the wood.

So remove the stop_machine for the module list insert and just
do a list_add_rcu() instead.

Module removal will still do a stop_machine of course, it needs
that for other reasons.

v2: Revised readers based on Paul's comments. All readers that only
    rely on disabled preemption need to be changed to list_for_each_rcu().
    Done that. The others are ok because they have the modules mutex.
    Also added a possible missing preempt disable for print_modules().

[cc Paul McKenney for review. It's not RCU, but quite similar.]

Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-10-22 10:00:22 +11:00
..
irq genirq: fix name space collision of nr_irqs in autoprobe.c 2008-10-16 16:53:30 +02:00
power container freezer: skip frozen cgroups during power management resume 2008-10-20 08:52:34 -07:00
time Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
trace tracing/fastboot: improve help text 2008-10-14 14:27:20 +02:00
.gitignore
Kconfig.freezer container freezer: implement freezer cgroup subsystem 2008-10-20 08:52:34 -07:00
Kconfig.hz sched: fix SCHED_HRTICK dependency 2008-07-28 14:37:38 +02:00
Kconfig.preempt
Makefile Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-10-20 13:35:07 -07:00
acct.c tty: Fix abusers of current->sighand->tty 2008-10-13 09:51:42 -07:00
audit.c [PATCH] Fix the bug of using AUDIT_STATUS_RATE_LIMIT when set fail, no error output. 2008-08-01 12:15:16 -04:00
audit.h
audit_tree.c [PATCH] list_for_each_rcu must die: audit 2008-05-17 03:30:23 -04:00
auditfilter.c Re: [PATCH] the loginuid field should be output in all AUDIT_CONFIG_CHANGE audit messages 2008-08-01 12:15:03 -04:00
auditsc.c tty: Fix abusers of current->sighand->tty 2008-10-13 09:51:42 -07:00
backtracetest.c backtrace: replace timer with tasklet + completions 2008-06-27 18:09:16 +02:00
bounds.c Add kbuild.h that contains common definitions for kbuild users 2008-04-29 08:06:29 -07:00
capability.c security: Fix setting of PF_SUPERPRIV by __capable() 2008-08-14 22:59:43 +10:00
cgroup.c cgroups: convert tasks file to use a seq_file with shared pid array 2008-10-20 08:52:38 -07:00
cgroup_debug.c cgroups: fix probable race with put_css_set[_taskexit] and find_css_set 2008-10-20 08:52:38 -07:00
cgroup_freezer.c container freezer: rename check_if_frozen() 2008-10-20 08:52:34 -07:00
compat.c Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
configs.c kernel/configs.c: remove useless comments 2008-10-20 08:52:34 -07:00
cpu.c Merge branches 'sched/devel', 'sched/cpu-hotplug', 'sched/cpusets' and 'sched/urgent' into sched/core 2008-10-08 11:31:02 +02:00
cpuset.c cpuset: use seq_*mask_* to print masks 2008-10-20 08:52:39 -07:00
delayacct.c per-task-delay-accounting: update taskstats for memory reclaim delay 2008-07-25 10:53:47 -07:00
dma-coherent.c dma-coherent: export dma_[alloc|release]_from_coherent methods 2008-08-22 08:34:53 +02:00
dma.c kernel/dma.c: remove a CVS keyword 2008-10-16 11:21:30 -07:00
exec_domain.c [PATCH] kill altroot 2008-07-26 20:53:20 -04:00
exit.c Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-10-20 13:35:07 -07:00
extable.c
fork.c Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-10-20 13:35:07 -07:00
freezer.c container freezer: implement freezer cgroup subsystem 2008-10-20 08:52:34 -07:00
futex.c futexes: fix fault handling in futex_lock_pi 2008-06-23 13:31:15 +02:00
futex_compat.c
hrtimer.c Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
itimer.c timers: fix itimer/many thread hang 2008-09-14 16:25:35 +02:00
kallsyms.c kernel/kallsyms.c: fix double return 2008-10-16 11:21:32 -07:00
kexec.c kexec: fix crash_save_vmcoreinfo_init build problem 2008-10-20 15:28:50 -07:00
kfifo.c
kgdb.c kgdb: call touch_softlockup_watchdog on resume 2008-10-06 13:50:59 -05:00
kmod.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus 2008-10-16 12:38:34 -07:00
kprobes.c make kprobes.c:kretprobe_table_lock() static 2008-10-16 11:21:52 -07:00
ksysfs.c profiling: dynamically enable readprofile at runtime 2008-10-16 11:21:31 -07:00
kthread.c Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-10-20 13:35:07 -07:00
latencytop.c kernel: use non-racy method for proc entries creation 2008-04-29 08:06:22 -07:00
lockdep.c lockdep: fix invalid list_del_rcu in zap_class 2008-08-27 08:40:36 +02:00
lockdep_internals.h lockdep: build fix 2008-08-13 12:55:10 +02:00
lockdep_proc.c lockstat: fix numerical output rounding error 2008-08-26 10:37:46 +02:00
marker.c markers: bit-field is not thread-safe nor smp-safe 2008-10-14 10:38:45 +02:00
module.c Remove stop_machine during module load v2 2008-10-22 10:00:22 +11:00
mutex-debug.c mutex-debug: check mutex magic before owner 2008-05-16 16:53:35 +02:00
mutex-debug.h
mutex.c locking: fix mutex @key parameter kernel-doc notation 2008-07-28 18:12:36 +02:00
mutex.h
notifier.c ftrace: ignore functions that cannot be kprobe-ed 2008-10-14 10:34:22 +02:00
ns_cgroup.c cgroup_clone: use pid of newly created task for new cgroup 2008-07-25 10:53:37 -07:00
nsproxy.c removed unused #include <linux/version.h>'s 2008-08-23 12:14:12 -07:00
panic.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6 2008-10-17 09:50:12 -07:00
params.c
pid.c pidns: remove now unused find_pid function. 2008-07-25 10:53:45 -07:00
pid_namespace.c pid_ns: (BUG 11391) change ->child_reaper when init->group_leader exits 2008-09-02 19:21:38 -07:00
pm_qos_params.c pm_qos_requirement might sleep 2008-09-02 19:21:40 -07:00
posix-cpu-timers.c timers: fix itimer/many thread hang, v2 2008-09-23 13:38:44 +02:00
posix-timers.c Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
printk.c Merge branch 'core-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-10-16 15:17:40 -07:00
profile.c profiling: dynamically enable readprofile at runtime 2008-10-16 11:21:31 -07:00
ptrace.c make ptrace_untrace() static 2008-10-20 08:52:39 -07:00
rcuclassic.c rcu: RCU-based detection of stalled CPUs for Classic RCU, fix 2008-10-03 10:41:00 +02:00
rcupdate.c rcu: fix synchronize_rcu() so that kernel-doc works 2008-08-21 09:31:44 +02:00
rcupreempt.c byteorder: remove direct includes of linux/byteorder/swab[b].h 2008-10-20 08:52:40 -07:00
rcupreempt_trace.c rcu: trace fix possible mem-leak 2008-08-15 17:54:40 +02:00
rcutorture.c byteorder: remove direct includes of linux/byteorder/swab[b].h 2008-10-20 12:51:53 -07:00
relay.c relay: fix "full buffer with exactly full last subbuffer" accounting problem 2008-08-05 14:33:46 -07:00
res_counter.c cgroup files: convert res_counter_write() to be a cgroups write_string() handler 2008-07-25 10:53:36 -07:00
resource.c Merge branch 'core-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-10-16 15:17:40 -07:00
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c sysdev: Pass the attribute to the low level sysdev show/store function 2008-07-21 21:55:02 -07:00
rtmutex.c
rtmutex.h
rtmutex_common.h
rwsem.c
sched.c Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-10-20 13:35:07 -07:00
sched_clock.c sched_clock: prevent scd->clock from moving backwards 2008-10-10 11:17:04 +02:00
sched_cpupri.c sched: use a 2-d bitmap for searching lowest-pri CPU 2008-06-06 15:19:28 +02:00
sched_cpupri.h sched: fix the cpuprio count really 2008-06-06 15:19:44 +02:00
sched_debug.c [PATCH] signal, procfs: some lock_task_sighand() users do not need rcu_read_lock() 2008-10-10 04:18:57 +04:00
sched_fair.c Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
sched_features.h sched: turn off WAKEUP_OVERLAP 2008-09-22 16:29:00 +02:00
sched_idletask.c sched: wakeup preempt when small overlap 2008-09-22 16:28:32 +02:00
sched_rt.c Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
sched_stats.h timers: fix itimer/many thread hang, v3 2008-09-27 20:04:45 +02:00
seccomp.c
semaphore.c semaphore: __down_common: use signal_pending_state() 2008-08-05 14:33:47 -07:00
signal.c Merge branch 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2008-10-20 13:35:07 -07:00
smp.c smp: have smp_call_function_single() detect invalid CPUs 2008-08-25 17:45:48 -07:00
softirq.c Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
softlockup.c Make the taint flags reliable 2008-10-16 11:21:31 -07:00
spinlock.c lockdep: spin_lock_nest_lock(), checkpatch fixes 2008-08-13 13:56:51 +02:00
srcu.c
stacktrace.c stacktrace: fix modular build, export print_stack_trace and save_stack_trace 2008-06-30 09:20:55 +02:00
stop_machine.c stop_machine: remove unused variable 2008-08-12 17:52:55 +10:00
sys.c Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
sys_ni.c Configure out AIO support 2008-10-16 11:21:51 -07:00
sysctl.c vmscan: unevictable LRU scan sysctl 2008-10-20 08:52:31 -07:00
sysctl_check.c sysctl: check for bogus modes 2008-07-25 10:53:45 -07:00
taskstats.c taskstats: remove initialization of static per-cpu variable 2008-07-25 10:53:47 -07:00
test_kprobes.c
time.c Make constants in kernel/timeconst.h fixed 64 bits 2008-05-02 16:18:42 -07:00
timeconst.pl Make constants in kernel/timeconst.h fixed 64 bits 2008-05-02 16:18:42 -07:00
timer.c Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus 2008-10-20 13:14:06 +02:00
tracepoint.c tracepoints: fix reentrancy 2008-10-14 10:38:23 +02:00
tsacct.c task IO accounting: move all IO statistics in struct task_io_accounting 2008-07-27 16:12:28 -07:00
uid16.c
user.c sched: rt-bandwidth for user grouping interface 2008-08-19 13:10:09 +02:00
user_namespace.c removed unused #include <linux/version.h>'s 2008-08-23 12:14:12 -07:00
utsname.c removed unused #include <linux/version.h>'s 2008-08-23 12:14:12 -07:00
utsname_sysctl.c sysctl: simplify ->strategy 2008-10-16 11:21:47 -07:00
wait.c wait: kill is_sync_wait() 2008-10-16 11:21:31 -07:00
workqueue.c Remove Andrew Morton's old email accounts 2008-10-16 11:21:32 -07:00