Increase spin dump timeout so that it is back in sync with the
upstream value.
Change-Id: I4b8896b69dadd66196090d86e40da89766b048e6
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
On certain targets the worst case console buffer draining time can
exceed the aggressive spin dump timeout value. Relax the timeout value
to cater to these scenarios.
Change-Id: I7312ffe06bafd2dc7adf0f4e8b73a53fc5839235
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
Data corruptions in the kernel often end up in system crashes that
are easier to debug closer to the time of detection. Specifically,
if we do not panic immediately after lock or list corruptions have been
detected, the problem context is lost in the ensuing system mayhem.
Add support for allowing system crash immediately after such corruptions
are detected. The CONFIG option controls the enabling/disabling of the
feature.
Change-Id: I9b2eb62da506a13007acff63e85e9515145909ff
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
The logic in do_raw_spin_lock attempts to acquire a spinlock
by invoking arch_spin_trylock in a loop with a delay between
each attempt. Now consider the following situation in a 2
CPU system:
1. Cpu 0 continually acquires and releases a spinlock in a
tight loop; it stays in this loop until some condition X
is satisfied. X can only be satisfied by another CPU.
2. Cpu 1 tries to acquire the same spinlock, in an attempt
to satisfy the aforementioned condition X. However, it
never sees the unlocked value of the lock because the
debug spinlock code uses trylock instead of just lock;
it checks at all the wrong moments - whenever Cpu 0 has
locked the lock.
Now in the absence of debug spinlocks, the architecture specific
spinlock code can correctly allow Cpu1 to wait in a "queue"
(e.g., ticket spinlocks), ensuring that it acquires the lock at
some point. However, with the debug spinlock code, livelock
can easily occur due to the use of try_lock, which obviously
cannot put the CPU in that "queue".
Address this by actually attempting arch_spin_lock once it is
suspected that there is a spinlock lockup. If we're in a
situation that is described above, the arch_spin_lock should
succeed; otherwise other timeout mechanisms (e.g., watchdog)
should alert the system of a lockup.
Additionally, the delay between each trylock attempt adds up
to a total delay of 1 second. On some embedded architectures,
this is an unacceptably large value. Reduce this to a ~62 ms
delay.
CRs-Fixed: 393351
Change-Id: I56f0d8f5e483cd7e8167fc7a363b9de7777a0830
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>
If one has two spinlocks embedded in a structure that kallsyms
knows about and one of the spinlocks locks up we will print the
name of the containing structure instead of the address of the
lock. This is quite bad, so let's use %pS instead of %ps so we
get an offset into the symbol so we can determine which lock is
having problems.
Change-Id: If6fbb2eb2316b846d96da76c35fcfeadbef64401
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This file was mismerged in the 3.4 kernel upgrade. We shouldn't
print the lockup twice.
Change-Id: If09a07d8b6c570632e1abac0a23c3ed203cd3ced
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
AU_LINUX_ANDROID_ICS.04.00.04.00.126 from msm-3.0.
First parent is from google/android-3.4.
* commit 'AU_LINUX_ANDROID_ICS.04.00.04.00.126': (8712 commits)
PRNG: Device tree entry for qrng device.
vidc:1080p: Set video core timeout value for Thumbnail mode
msm: sps: improve the debugging support in SPS driver
board-8064 msm: Overlap secure and non secure video firmware heaps.
msm: clock: Add handoff ops for 7x30 and copper XO clocks
msm_fb: display: Wait for external vsync before DTV IOMMU unmap
msm: Fix ciruclar dependency in debug UART settings
msm: gdsc: Add GDSC regulator driver for msm-copper
defconfig: Enable Mobicore Driver.
mobicore: Add mobicore driver.
mobicore: rename variable to lower case.
mobicore: rename folder.
mobicore: add makefiles
mobicore: initial import of kernel driver
ASoC: msm: Add SLIMBUS_2_RX CPU DAI
board-8064-gpio: Update FUNC for EPM SPI CS
msm_fb: display: Remove chicken bit config during video playback
mmc: msm_sdcc: enable the sanitize capability
msm-fb: display: lm2 writeback support on mpq platfroms
msm_fb: display: Disable LVDS phy & pll during panel off
...
Signed-off-by: Steve Muckle <smuckle@codeaurora.org>
When a spinlock warning is printed we usually get
BUG: spinlock bad magic on CPU#0, modprobe/111
lock: 0xdff09f38, .magic: 00000000, .owner: /0, .owner_cpu: 0
but it's nicer to print the symbol for the lock if we have it so
that we can avoid 'grep dff09f38 /proc/kallsyms' to find out
which lock it was. Use kallsyms to print the symbol name so we
get something a bit easier to read
BUG: spinlock bad magic on CPU#0, modprobe/112
lock: test_lock, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
Change-Id: I833d011da8362960e97c53ebd59236ac7eb147fd
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete the include. Fix up any implicit
include dependencies that were being masked by module.h along
the way.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
When SPIN_BUG_ON is triggered, the lock owner information is reported.
But it is omitted when spinlock lockup is detected.
This information is useful especially on the architectures which don't
implement trigger_all_cpu_backtrace() that is called just after detecting
lockup. So report it and also avoid message format duplication.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The name space hierarchy for the internal lock functions is now a bit
backwards. raw_spin* functions map to _spin* which use __spin*, while
we would like to have _raw_spin* and __raw_spin*.
_raw_spin* is already used by lock debugging, so rename those funtions
to do_raw_spin* to free up the _raw_spin* name space.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Now that the raw_spin name space is freed up, we can implement
raw_spinlock and the related functions which are used to annotate the
locks which are not converted to sleeping spinlocks in preempt-rt.
A side effect is that only such locks can be used with the low level
lock fsunctions which circumvent lockdep.
For !rt spin_* functions are mapped to the raw_spin* implementations.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
The raw_spin* namespace was taken by lockdep for the architecture
specific implementations. raw_spin_* would be the ideal name space for
the spinlocks which are not converted to sleeping locks in preempt-rt.
Linus suggested to convert the raw_ to arch_ locks and cleanup the
name space instead of using an artifical name like core_spin,
atomic_spin or whatever
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: linux-arch@vger.kernel.org
The task_struct->pid member is going to be deprecated, so start
using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in
the kernel.
The first thing to start with is the pid, printed to dmesg - in
this case we may safely use task_pid_nr(). Besides, printks produce
more (much more) than a half of all the explicit pid usage.
[akpm@linux-foundation.org: git-drm went and changed lots of stuff]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When a spinlock lockup occurs, arrange for the NMI code to emit an all-cpu
backtrace, so we get to see which CPU is holding the lock, and where.
Cc: Andi Kleen <ak@muc.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andi Kleen <ak@suse.de>
This annotation makes it possible to assign a subclass on lock init. This
annotation is meant to reduce the _nested() annotations by assigning a
default subclass.
One could do without this annotation and rely on lockdep_set_class()
exclusively, but that would require a manual stack of struct lock_class_key
objects.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
In spinlock_debug.c, the spinloops call __delay() on every iteration.
Because that is an external function, (jiffies_per_loop * HZ), the loop's
iteration limit, gets recomputed every time. Caching it explicitly
prevents that.
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We've confirmed that the debug version of write_lock() can get stuck for long
enough to cause NMI watchdog timeouts and hence a crash.
We don't know why, yet. Disable it for now.
Also disable the similar read_lock() code. Just in case.
Thanks to Dave Olson <olson@unixfolk.com> for reporting and testing.
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the lock validator framework to prove spinlock and rwlock locking
correctness.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Generic lock debugging:
- generalized lock debugging framework. For example, a bug in one lock
subsystem turns off debugging in all lock subsystems.
- got rid of the caller address passing (__IP__/__IP_DECL__/etc.) from
the mutex/rtmutex debugging code: it caused way too much prototype
hackery, and lockdep will give the same information anyway.
- ability to do silent tests
- check lock freeing in vfree too.
- more finegrained debugging options, to allow distributions to
turn off more expensive debugging features.
There's no separate 'held mutexes' list anymore - but there's a 'held locks'
stack within lockdep, which unifies deadlock detection across all lock
classes. (this is independent of the lockdep validation stuff - lockdep first
checks whether we are holding a lock already)
Here are the current debugging options:
CONFIG_DEBUG_MUTEXES=y
CONFIG_DEBUG_LOCK_ALLOC=y
which do:
config DEBUG_MUTEXES
bool "Mutex debugging, basic checks"
config DEBUG_LOCK_ALLOC
bool "Detect incorrect freeing of live mutexes"
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The spinlock-debug wait-loop was using loops_per_jiffy to detect too long
spinlock waits - but on fast CPUs this led to a way too fast timeout and false
messages.
The fix is to include a __delay(1) call in the loop, to correctly approximate
the intended delay timeout of 1 second. The code assumes that every
architecture implements __delay(1) to last around 1/(loops_per_jiffy*HZ)
seconds.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When a spinlock debugging check hits, we print the CPU number as an
informational thing - but there is no guarantee that preemption is off
at that point - hence we should use raw_smp_processor_id(). Otherwise
DEBUG_PREEMPT will print a warning.
With this fix the warning goes away and only the spinlock-debugging info
is printed.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch (written by me and also containing many suggestions of Arjan van
de Ven) does a major cleanup of the spinlock code. It does the following
things:
- consolidates and enhances the spinlock/rwlock debugging code
- simplifies the asm/spinlock.h files
- encapsulates the raw spinlock type and moves generic spinlock
features (such as ->break_lock) into the generic code.
- cleans up the spinlock code hierarchy to get rid of the spaghetti.
Most notably there's now only a single variant of the debugging code,
located in lib/spinlock_debug.c. (previously we had one SMP debugging
variant per architecture, plus a separate generic one for UP builds)
Also, i've enhanced the rwlock debugging facility, it will now track
write-owners. There is new spinlock-owner/CPU-tracking on SMP builds too.
All locks have lockup detection now, which will work for both soft and hard
spin/rwlock lockups.
The arch-level include files now only contain the minimally necessary
subset of the spinlock code - all the rest that can be generalized now
lives in the generic headers:
include/asm-i386/spinlock_types.h | 16
include/asm-x86_64/spinlock_types.h | 16
I have also split up the various spinlock variants into separate files,
making it easier to see which does what. The new layout is:
SMP | UP
----------------------------|-----------------------------------
asm/spinlock_types_smp.h | linux/spinlock_types_up.h
linux/spinlock_types.h | linux/spinlock_types.h
asm/spinlock_smp.h | linux/spinlock_up.h
linux/spinlock_api_smp.h | linux/spinlock_api_up.h
linux/spinlock.h | linux/spinlock.h
/*
* here's the role of the various spinlock/rwlock related include files:
*
* on SMP builds:
*
* asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
* initializers
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* asm/spinlock.h: contains the __raw_spin_*()/etc. lowlevel
* implementations, mostly inline assembly code
*
* (also included on UP-debug builds:)
*
* linux/spinlock_api_smp.h:
* contains the prototypes for the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*
* on UP builds:
*
* linux/spinlock_type_up.h:
* contains the generic, simplified UP spinlock type.
* (which is an empty structure on non-debug builds)
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* linux/spinlock_up.h:
* contains the __raw_spin_*()/etc. version of UP
* builds. (which are NOPs on non-debug, non-preempt
* builds)
*
* (included on UP-non-debug builds:)
*
* linux/spinlock_api_up.h:
* builds the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*/
All SMP and UP architectures are converted by this patch.
arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
crosscompilers. m32r, mips, sh, sparc, have not been tested yet, but should
be mostly fine.
From: Grant Grundler <grundler@parisc-linux.org>
Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU).
Builds 32-bit SMP kernel (not booted or tested). I did not try to build
non-SMP kernels. That should be trivial to fix up later if necessary.
I converted bit ops atomic_hash lock to raw_spinlock_t. Doing so avoids
some ugly nesting of linux/*.h and asm/*.h files. Those particular locks
are well tested and contained entirely inside arch specific code. I do NOT
expect any new issues to arise with them.
If someone does ever need to use debug/metrics with them, then they will
need to unravel this hairball between spinlocks, atomic ops, and bit ops
that exist only because parisc has exactly one atomic instruction: LDCW
(load and clear word).
From: "Luck, Tony" <tony.luck@intel.com>
ia64 fix
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjanv@infradead.org>
Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se>
Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Francescodario Cuzzocrea
Syed Rameez Mustafa
Vikram Mulukutla
Stephen Boyd
Steve Muckle
Paul Gortmaker
Akinobu Mita
Thomas Gleixner
Pavel Emelyanov
Andrew Morton
Peter Zijlstra
Chuck Ebbert
Ingo Molnar
Jörn Engel
Dave Jones