Select CONFIG_PREEMPT_COUNT when we enable the sleeping inside
spinlock detection, so that the preempt offset gets correctly
incremented/decremented from preempt_disable()/preempt_enable().
This makes the preempt count eventually working in !CONFIG_PREEMPT
when that debug option is set and thus fixes the detection of explicit
preemption disabled sections under such config. Code that sleeps
in explicitly preempt disabled section can be finally spotted
in non-preemptible kernels.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
b43: fix comment typo reqest -> request
Haavard Skinnemoen has left Atmel
cris: typo in mach-fs Makefile
Kconfig: fix copy/paste-ism for dell-wmi-aio driver
doc: timers-howto: fix a typo ("unsgined")
perf: Only include annotate.h once in tools/perf/util/ui/browsers/annotate.c
md, raid5: Fix spelling error in comment ('Ofcourse' --> 'Of course').
treewide: fix a few typos in comments
regulator: change debug statement be consistent with the style of the rest
Revert "arm: mach-u300/gpio: Fix mem_region resource size miscalculations"
audit: acquire creds selectively to reduce atomic op overhead
rtlwifi: don't touch with treewide double semicolon removal
treewide: cleanup continuations and remove logging message whitespace
ath9k_hw: don't touch with treewide double semicolon removal
include/linux/leds-regulator.h: fix syntax in example code
tty: fix typo in descripton of tty_termios_encode_baud_rate
xtensa: remove obsolete BKL kernel option from defconfig
m68k: fix comment typo 'occcured'
arch:Kconfig.locks Remove unused config option.
treewide: remove extra semicolons
...
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
seqlock: Don't smp_rmb in seqlock reader spin loop
watchdog, hung_task_timeout: Add Kconfig configurable default
lockdep: Remove cmpxchg to update nr_chain_hlocks
lockdep: Print a nicer description for simple irq lock inversions
lockdep: Replace "Bad BFS generated tree" message with something less cryptic
lockdep: Print a nicer description for irq inversion bugs
lockdep: Print a nicer description for simple deadlocks
lockdep: Print a nicer description for normal deadlocks
lockdep: Print a nicer description for irq lock inversions
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-2.6-cm:
kmemleak: Initialise kmemleak after debug_objects_mem_init()
kmemleak: Select DEBUG_FS unconditionally in DEBUG_KMEMLEAK
kmemleak: Do not return a pointer to an object that kmemleak did not get
In the past DEBUG_FS used to depend on SYSFS and DEBUG_KMEMLEAK selected
it conditionally. This is no longer the case, so always select DEBUG_FS
via DEBUG_KMEMLEAK.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The prohibition of DEBUG_OBJECTS_RCU_HEAD from !PREEMPT was due to the
fixup actions. So just produce a warning from !PREEMPT.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The RCU CPU stall warnings can now be controlled using the
rcu_cpu_stall_suppress boot-time parameter or via the same parameter
from sysfs. There is therefore no longer any reason to have
kernel config parameters for this feature. This commit therefore
removes the RCU_CPU_STALL_DETECTOR and RCU_CPU_STALL_DETECTOR_RUNNABLE
kernel config parameters. The RCU_CPU_STALL_TIMEOUT parameter remains
to allow the timeout to be tuned and the RCU_CPU_STALL_VERBOSE parameter
remains to allow task-stall information to be suppressed if desired.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This patch allows the default value for sysctl_hung_task_timeout_secs
to be set at build time. The feature carries virtually no overhead,
so it makes sense to keep it enabled. On heavily loaded systems, though,
it can end up triggering stack traces when there is no bug other than
the system being underprovisioned. We use this patch to keep the hung task
facility available but disabled at boot-time.
The default of 120 seconds is preserved. As a note, commit e162b39a may
have accidentally reverted commit fb822db4, which raised the default from
120 seconds to 480 seconds.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Acked-by: Mandeep Singh Baines <msb@google.com>
Link: http://lkml.kernel.org/r/4DB8600C.8080000@suse.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cite Documentation/kernel-parameters.txt for an alternative to
building with PRINTK_TIME compiled in.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
mm/kmemleak-test.c is used to provide an example of how kmemleak
tool works.
Memory is leaked at module unload-time, so building the test
in kernel (Y) makes the leaks impossible and the test useless.
Qualify DEBUG_KMEMLEAK_TEST config symbol with "depends on m",
to restrict module-only building.
Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1. simple_strto*() do not contain overflow checks and crufty,
libc way to indicate failure.
2. strict_strto*() also do not have overflow checks but the name and
comments pretend they do.
3. Both families have only "long long" and "long" variants,
but users want strtou8()
4. Both "simple" and "strict" prefixes are wrong:
Simple doesn't exactly say what's so simple, strict should not exist
because conversion should be strict by default.
The solution is to use "k" prefix and add convertors for more types.
Enter
kstrtoull()
kstrtoll()
kstrtoul()
kstrtol()
kstrtouint()
kstrtoint()
kstrtou64()
kstrtos64()
kstrtou32()
kstrtos32()
kstrtou16()
kstrtos16()
kstrtou8()
kstrtos8()
Include runtime testsuite (somewhat incomplete) as well.
strict_strto*() become deprecated, stubbed to kstrto*() and
eventually will be removed altogether.
Use kstrto*() in code today!
Note: on some archs _kstrtoul() and _kstrtol() are left in tree, even if
they'll be unused at runtime. This is temporarily solution,
because I don't want to hardcode list of archs where these
functions aren't needed. Current solution with sizeof() and
__alignof__ at least always works.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We've been burned by regressions/bugs which we later realized could have
been triaged quicker if only we'd paid closer attention to dmesg. To make
it easier to audit dmesg, we'd like to make DEFAULT_MESSAGE_LEVEL
Kconfig-settable. That way we can set it to KERN_NOTICE and audit any
messages <= KERN_WARNING.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joe Perches <joe@perches.com>
Cc: Olof Johansson <olofj@chromium.org>
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>
When a cpu is considered stuck, instead of limping along and just printing
a warning, it is sometimes preferred to just panic, let kdump capture the
vmcore and reboot. This gets the machine back into a stable state quickly
while saving the info that got it into a stuck state to begin with.
Add a Kconfig option to allow users to set the hardlockup to panic
by default. Also add in a 'nmi_watchdog=nopanic' to override this.
[akpm@linux-foundation.org: fix strncmp length]
Signed-off-by: Don Zickus <dzickus@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
kbuild: Make DEBUG_SECTION_MISMATCH selectable, but not on by default
genksyms: Regenerate lexer and parser
genksyms: Track changes to enum constants
genksyms: simplify usage of find_symbol()
genksyms: Add helpers for building string lists
genksyms: Simplify printing of symbol types
genksyms: Simplify lexer
genksyms: Do not paste the bison header file to lex.c
modpost: fix trailing comma
KBuild: silence "'scripts/unifdef' is up to date."
kbuild: Add extra gcc checks
kbuild: reenable section mismatch analysis
unifdef: update to upstream version 2.5
CONFIG_DEBUG_SECTION_MISMATCH has also runtime effects due to the
-fno-inline-functions-called-once compiler flag, so forcing it on
everyone is not a good idea.
Signed-off-by: Michal Marek <mmarek@suse.cz>
This was disabled in commit
e5f95c8 (kbuild: print only total number of section mismatces found)
because there were too many warnings. Now we're down to a reasonable
number again, so we start scaring people with the details.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.
This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel. A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).
Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: David Woodhouse <david.woodhouse@intel.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Greg KH <gregkh@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robin Holt <holt@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
