This matters to any sort of device that is wired to one of the CPU
interrupt pins on an SMP system. Typically the scenario is most easily
triggered with the count/compare timer interrupt where the same interrupt
number and thus irq_desc is used on each processor.
CPU A CPU B
do_IRQ()
generic_handle_irq()
handle_level_irq()
spin_lock(desc_lock)
set IRQ_INPROGRESS
spin_unlock(desc_lock)
do_IRQ()
generic_handle_irq()
handle_level_irq()
spin_lock(desc_lock)
IRQ_INPROGRESS set => bail out
spin_lock(desc_lock)
clear IRQ_INPROGRESS
spin_unlock(desc_lock)
In case of the cp0 compare interrupt this means the interrupt will be
acked and not handled or re-armed on CPU b, so there won't be any timer
interrupt until the count register wraps around.
With kernels 2.6.20 ... 2.6.23 we usually were lucky that things were just
working right on VSMP because the count registers are synchronized on
bootup so it takes something that disables interrupts for a long time on
one processor to trigger this one.
For scenarios where an interrupt is multicasted or broadcasted over several
CPUs the existing code was safe and the fix will break it. There is no
way to know in the interrupt controller code because it is abstracted from
the platform code. I think we do not have such a setup currently, so this
should be ok.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The GNU `config.guess' uses "linux-gnu" as the canonical system name.
Fix the list of compiler prefixes checked to spell it correctly.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Adds a JR.HB after halting a TC, to ensure that the TC has really halted.
only modifies the TCSTATUS register when the TC is safely halted.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We have no guarantee by the generic time code that the timer is stopped
when the ->next_event method is called. Modifying the Timer Initial Count
register while the timer is enabled has UNPREDICTABLE effect according to
the BCM1250/BCM1125/BCM1125H User Manual. So stop the timer before
reprogramming.
This is a paranoia fix; no ill effects have been observed previously.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
For the old minimum of a single tick a value of zero would be programmed
into the init value register which in the BCM1250/BCM1125/BCM1125H User
Manual in the Timer Special Cases section is documented to have
UNPREDICTABLE effect.
Observable sympthoms of this bug were hangs of several seconds on the
console during bootup and later if both dyntick and highres timer options
were activated.
In theory contiguous mode of the timers is also affected but in an act of
hopeless lack of realism I'll assume nobody will ever configure a KERNEL
for HZ > 500kHz but if so I leave that to evolution to sort out.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The range of MIPS_CPU IRQ and the range of LASAT IRQ overlap.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Shadow register support would not possibly have worked on multicore
systems. The support code for it was also depending not on MIPS R2 but
VSMP or SMTC kernels even though it makes perfect sense with UP kernels.
SR sets are a scarce resource and the expected usage pattern is that
users actually hardcode the register set numbers in their code. So fix
the allocator by ditching it. Move the remaining CPU probe bits into
the generic CPU probe.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
iounmap if pci clock is over 33MHz. Cosmetic because the iomap() in this
case is just a bit of address magic.
Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Acked-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The recent switch of the Sibyte SOCs from the processor specific cache
managment code in c-sb1.c to c-r4k.c lost this old hack
[MIPS] Hack for SB1 cache issues
Removing flush_icache_page a while ago broke SB1 which was using an empty
flush_data_cache_page function. This glues things well enough so a more
efficient but also more intrusive solution can be found later.
Signed-Off-By: Thiemo Seufer <ths@networkno.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
in the hope it was no longer needed. As it turns it still is so resurrect
it until there is a better solution.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The Jazz machines have to use the PIT timer for dyntick and highresolution
kernels. This may break because currently just like i386 used to do MIPS
uses two separate spinlocks in the actual PIT code and the PC speaker
code. So switch to do it the same that x86 currently does PIT locking.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix ISA irq acknowledge.
Make r4030 clockevent code look like other mips clockevent code.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Register A20R clockevent.
Remove PIT timer setup because it doesn't work
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/au1000/pb1200/irqmap.c:101: warning: ignoring return value of 'request_irq', declared with attribute warn_unused_result
And while at it a few coding style cleanups.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* Do not include unnecessary headers.
* Do not mention time.README.
* Do not mention mips_timer_ack.
* Make clocksource_mips static. It is now dedicated to c0_timer.
* Initialize clocksource_mips.read statically.
* Remove null_hpt_read.
* Remove an argument of plat_timer_setup. It is just a placeholder.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When GDB writes a breakpoint into address area of inferior process the
kernel needs to invalidate the modified memory in the inferior which
is done by calling flush_cache_page which in turns calls
r4k_flush_cache_page and local_r4k_flush_cache_page for VSMP or SMTC
kernel via r4k_on_each_cpu().
As the VSMP and SMTC SMP kernels for 34K are running on a single shared
caches it is possible to get away without interprocessor function calls.
This optimization is implemented in r4k_on_each_cpu, so
local_r4k_flush_cache_page is only ever called on the local CPU.
This is where the following code in local_r4k_flush_cache_page() strikes:
/*
* If ownes no valid ASID yet, cannot possibly have gotten
* this page into the cache.
*/
if (cpu_context(smp_processor_id(), mm) == 0)
return;
On VSMP and SMTC had a function of cpu_context() for each CPU(TC).
So in case another CPU than the CPU executing local_r4k_cache_flush_page
has not accessed the mm but one of the other CPUs has there may be data
to be flushed in the cache yet local_r4k_cache_flush_page will falsely
return leaving the I-cache inconsistent for the breakpoint.
While the issue was discovered with GDB it also exists in
local_r4k_flush_cache_range() and local_r4k_flush_cache().
Fixed by introducing a new function has_valid_asid which on MT kernels
returns true if a mm is active on any processor in the system.
This is relativly expensive since for memory acccesses in that loop
cache misses have to be assumed but it seems the most viable solution
for 2.6.23 and older -stable kernels.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Enable the onboard GenBus IDE interface in the default configuration.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Contrary to the belief of some, the R3000 and related processors did have
caches, both a data and an instruction cache. Here is an implementation
of r3k_flush_cache_page(), which is the processor-specific back-end for
flush_cache_range(), done according to the spec in
Documentation/cachetlb.txt.
While at it, remove an unused local function: get_phys_page(), do some
trivial formatting fixes and modernise debugging facilities.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
A comment on ptrace_getregs() states "Registers are sign extended to
fill the available space." but it is not true. Fix code to match the
comment. Also fix casts on each caller to get rid of some warnings.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch separates the platform devices registration for the MTX-1
specific devices: GPIO leds and watchdog.
[Minor fixup and formatting change -- Ralf]
Signed-off-by: Florian Fainelli <florian.fainelli@telecomint.eu>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Mmap with MAP_FIXED was not validating the addr and len parameters. This
leads to the failure of GCC's gcc.c-torture/execute/loop-2[fg].c testcases
when using the o32 ABI on a 64 bit kernel.
These testcases try to mmap 65536 bytes at 0x7fff8000 and then access all
the memory. In 2.6.18 and 2.6.23.1 (and likely other versions as well)
the kernel maps the requested memory, but since half of it is above
0x80000000 a SIGBUS is generated when it is accessed.
This patch moves the len validation above the MAP_FIXED processing so that
it is always validated. It also adds validation to the addr parameter for
MAP_FIXED mappings.
Signed-off-by: David Daney <ddaney@avtrex.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Try increasingly longer time periods starting of at 0x10 cycles. This
should be fast on hardware and work nicely with emulators.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The expression "(long)(read_c0_count() - cnt)" can never be a negative
value on 64-bit kernel. Cast to "int" before comparison.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
They break the timer interrupt initialization and only seem to be a kludge
for initialization happening in the wrong order. Further testing done by
Thiemo confirms the suspicion that the other invocations also seem to have
useless.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Convert jmr3927_clock_event_device to more generic
txx9tmr_clock_event_device which supports one-shot mode. The
txx9tmr_clock_event_device can be used for TX49 too if the cp0 timer
interrupt was not available.
Convert jmr3927_hpt_read to txx9_clocksource driver which does not
depends jiffies anymore. The txx9_clocksource itself can be used for
TX49, but normally TX49 uses higher precision clocksource_mips.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fixme: At the time of this writing cevt-r4k.c doesn't yet know about how
to handle the alternate timer interrupt of the RM9000.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Since the cp0 compare interrupt handler isn't initialized by the time
plat_time_init is called don't set IE_IRQ5 anymore, cevt-r4k.c will do
that a little later itself.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The old plat_timer_setup hook is no longer getting called so the Alchemy
time initialization was getting skipped.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
clockevent_delta2ns() use the shift and mult value, so
clockevent_set_clock() should be called first.
Pointed out by Atsushi Nemoto.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
set_next_event() and set_mode() are always called with interrupt disabled.
irqsave and irqrestore are not necessary for spinlock.
Pointed out by Atsushi Nemoto.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Modify the SMTC initialization code to allow boot-time specification not
only of how many VPEs and TCs to use, but also how many TCs out of the
allowed pool are to be bound to VPE 0. The new boot option is "vpe0tcs=N",
where N is an integer. Using it in combination with the existing options
allows arbitrary assignments across the 2 VPEs of a 34K. e.g. "maxtcs=3
vpe0tcs=1" forces VPE0 to have 1 TC, while VPE1 has 2, and "maxtcs=4
vpe0tcs=3" forces VPE0 to have 3 TCs, while VPE1 gets 1. If no vpe0tcs
option is specified, the traditional algorithm of evenly dividing TCs
between available VPEs, with the odd "slop" going to VPE0, is retained.
The reason for doing this is to allow a finer balancing of TCs which can
handle I/O interrupts on Malta (those on VPE 0) and those which cannot.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] time: Make c0_compare_int_usable more bullet proof
[MIPS] Kbuild: Use the new cc-cross-prefix feature.
[MIPS] Fix include wrapper symbol to something sane.
[MIPS] Malta: Delete dead code.
[MIPS] time: Add GT641xx timer0 clockevent driver
[MIPS] time: SMP-proofing of Sibyte clockevent/clocksource code.
[MIPS] time: SMP/NUMA-proofing of IP27 HUB RT timer code.
[MIPS] time: Fix calculation in clockevent_set_clock()
And make use of it for Cobalt. A few others such as the Malta could make
use of it as well.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The BCM148 has 4 cores but there are also just 4 generic timers available
so use the ZBbus cycle counter instead of it. In addition the ZBbus
counter also offers a much higher resolution and 64-bit counting so I'm
considering a later complete conversion to it once I figure out if all
members of the Sibyte SOC family support it - the docs seem to agree but
the headers files seem to disagree ...
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Most of these fixes were already submitted for old kernel versions, and were
approved, but for some reason they never made it into the releases.
Because this is a consolidation of a couple old missed patches, it touches both
Kconfigs and documentation texts.
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Fix the various misspellings of "system", controller", "interrupt" and
"[un]necessary".
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] Delete totally outdated Documentation/mips/time.README
[MIPS] Kill duplicated setup_irq() for cp0 timer
[MIPS] Sibyte: Finish conversion to modern time APIs.
[MIPS] time: Helpers to compute clocksource/event shift and mult values.
[MIPS] SMTC: Build fix.
[MIPS] time: Delete dead code.
[MIPS] MIPSsim: Strip defconfig file to the bones.
Quoting Randy:
"It seems sad that this patch sources Kconfig.marker, a 7-line file,
20-something times. Yes, you (we) don't want to put those 7 lines into
20-something different files, so sourcing is the right thing.
However, what you did for avr32 seems more on the right track to me: make
_one_ Instrumentation support menu that includes PROFILING, OPROFILE, KPROBES,
and MARKERS and then use (source) that in all of the arches."
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
One of the easiest things to isolate is the pid printed in kernel log.
There was a patch, that made this for arch-independent code, this one makes
so for arch/xxx files.
It took some time to cross-compile it, but hopefully these are all the
printks in arch code.
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
remove asm/bitops.h includes
including asm/bitops directly may cause compile errors. don't include it
and include linux/bitops instead. next patch will deny including asm header
directly.
Cc: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
is_init() is an ambiguous name for the pid==1 check. Split it into
is_global_init() and is_container_init().
A cgroup init has it's tsk->pid == 1.
A global init also has it's tsk->pid == 1 and it's active pid namespace
is the init_pid_ns. But rather than check the active pid namespace,
compare the task structure with 'init_pid_ns.child_reaper', which is
initialized during boot to the /sbin/init process and never changes.
Changelog:
2.6.22-rc4-mm2-pidns1:
- Use 'init_pid_ns.child_reaper' to determine if a given task is the
global init (/sbin/init) process. This would improve performance
and remove dependence on the task_pid().
2.6.21-mm2-pidns2:
- [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc,
ppc,avr32}/traps.c for the _exception() call to is_global_init().
This way, we kill only the cgroup if the cgroup's init has a
bug rather than force a kernel panic.
[akpm@linux-foundation.org: fix comment]
[sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c]
[bunk@stusta.de: kernel/pid.c: remove unused exports]
[sukadev@us.ibm.com: Fix capability.c to work with threaded init]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Pavel Emelianov <xemul@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Herbert Poetzel <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The set of functions process_session, task_session, process_group and
task_pgrp is confusing, as the names can be mixed with each other when looking
at the code for a long time.
The proposals are to
* equip the functions that return the integer with _nr suffix to
represent that fact,
* and to make all functions work with task (not process) by making
the common prefix of the same name.
For monotony the routines signal_session() and set_signal_session() are
replaced with task_session_nr() and set_task_session(), especially since they
are only used with the explicit task->signal dereference.
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In pre-cgroup cpusets, a few config files enabled cpusets by default.
Signed-off-by: Paul Jackson <pj@sgi.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>
Ralf Baechle