| Commit message (Collapse) | Author | Age | Files | Lines |
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* 'hwmon-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6:
hwmon: (fschmd) Add support for the FSC Hades IC
hwmon: (fschmd) Add support for the FSC Syleus IC
i2c-i801: Instantiate FSC hardware montioring chips
dmi: Let dmi_walk() users pass private data
hwmon: Define a standard interface for chassis intrusion detection
Move the pcf8591 driver to hwmon
hwmon: (w83627ehf) Only expose in6 or temp3 on the W83667HG
hwmon: (w83627ehf) Add support for W83667HG
hwmon: (w83627ehf) Invert fan pin variables logic
hwmon: (hdaps) Fix Thinkpad X41 axis inversion
hwmon: (hdaps) Allow inversion of separate axis
hwmon: (ds1621) Clean up documentation
hwmon: (ds1621) Avoid unneeded register access
hwmon: (ds1621) Clean up register access
hwmon: (ds1621) Reorder code statements
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Add support for the Hades to the FSC hwmon driver.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
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Many thanks to Fujitsu Siemens Computers for providing docs and a
machine to test the driver on.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
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Detect various FSC hwmon IC's based on DMI tables and then let
the i2c-i801 driver instantiate the i2c client devices. Note that
some of the info in the added table is indentical for all rows, still
this is kept in the table to keep the code general and thus (hopefully)
easily extensible in the future.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
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At the moment, dmi_walk() lacks flexibility, users can't pass data to
the callback function. Add a pointer for private data to make this
function more flexible.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Roland Dreier <rolandd@cisco.com>
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Define a standard interface for the chassis intrusion detection feature
some hardware monitoring chips have. Some drivers have custom sysfs
entries for it, but a standard interface would allow integration with
user-space (namely libsensors.)
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Hans de Goede <j.w.r.degoede@hhs.nl>
Acked-by: Matt Roberds <mattroberds@cox.net>
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Directory drivers/i2c/chips is going away, so drivers there must find
new homes. For the pcf8591 driver, the best choice seems to be the
hwmon subsystem. While the Philips PCF8591 device isn't a typical
hardware monitoring chip, its DAC interface is compatible with the
hwmon one, so it fits somewhat.
If a better subsystem is ever created for ADC/DAC chips, the driver
could be moved there.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Aurelien Jarno <aurelien@aurel32.net>
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The pin for in6 and temp3 is shared on the W83667HG, so only one of
these features can be supported on any given system. Let the driver
select which one depending on the temp3 disabled bit.
Signed-off-by: Gong Jun <JGong@nuvoton.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
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Add initial support for the Nuvoton W83667HG chip to the w83627ehf
driver. It has been tested on ASUS P5QL PRO by Gong Jun.
At the moment there is still a usability issue which is that only in6
or temp3 can be present on the W83667HG, so the driver shouldn't
expose both. This will be addressed later.
Signed-off-by: Gong Jun <JGong@nuvoton.com>
Acked-by: David Hubbard <david.c.hubbard@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
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Use positive logic for fan pin variables (variable is set if pin is
used for fan), instead of negative logic which is error prone.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Gong Jun <JGong@nuvoton.com>
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Fix for kernel.org bug #7154: hdaps inversion of actual Thinkpad
X41's Y-axis.
Signed-off-by: Frank Seidel <frank@f-seidel.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
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Fix for kernel.org bug #7154: hdaps inversion of each axis. This
version is based on the work from Michael Ruoss <miruoss@student.ethz.ch>.
Signed-off-by: Frank Seidel <frank@f-seidel.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
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* The alarms sysfs file is deprecated, and individual alarm files are
self-explanatory.
* The driver doesn't implement high-reslution temperature readings so
don't document that.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Aurelien Jarno <aurelien@aurel32.net>
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Register access over SMBus isn't cheap, so avoid register access where
possible:
* Only write back the configuration register if it changed.
* Don't refresh the register cache when we don't have to.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Aurelien Jarno <aurelien@aurel32.net>
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Fix a few oddities in how the ds1621 driver accesses the registers:
* We don't need a wrapper to access the configuration register.
* Check for error before calling swab16. Error checking isn't
complete yet, but that's a start.
* Device-specific read functions should never be called during
detection, as by definition we don't know what device we are talking
to at that point.
* Likewise, don't assume that register reads succeed during detection.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Aurelien Jarno <aurelien@aurel32.net>
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Reorder the ds1621 driver code so that we can get rid of forward
function declarations.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Aurelien Jarno <aurelien@aurel32.net>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (33 commits)
lockdep: fix deadlock in lockdep_trace_alloc
lockdep: annotate reclaim context (__GFP_NOFS), fix SLOB
lockdep: annotate reclaim context (__GFP_NOFS), fix
lockdep: build fix for !PROVE_LOCKING
lockstat: warn about disabled lock debugging
lockdep: use stringify.h
lockdep: simplify check_prev_add_irq()
lockdep: get_user_chars() redo
lockdep: simplify get_user_chars()
lockdep: add comments to mark_lock_irq()
lockdep: remove macro usage from mark_held_locks()
lockdep: fully reduce mark_lock_irq()
lockdep: merge the !_READ mark_lock_irq() helpers
lockdep: merge the _READ mark_lock_irq() helpers
lockdep: simplify mark_lock_irq() helpers #3
lockdep: further simplify mark_lock_irq() helpers
lockdep: simplify the mark_lock_irq() helpers
lockdep: split up mark_lock_irq()
lockdep: generate usage strings
lockdep: generate the state bit definitions
...
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Heiko reported that we grab the graph lock with irqs enabled.
Fix this by providng the same wrapper as all other lockdep entry
functions have.
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Nick Piggin <npiggin@suse.de>
LKML-Reference: <1237544000.24626.52.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Impact: build fix
fix typo in mm/slob.c:
mm/slob.c:469: error: ‘flags’ undeclared (first use in this function)
mm/slob.c:469: error: (Each undeclared identifier is reported only once
mm/slob.c:469: error: for each function it appears in.)
Cc: Nick Piggin <npiggin@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090128135457.350751756@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Impact: fix build warning
Fix:
mm/vmscan.c: In function ‘kswapd’:
mm/vmscan.c:1969: warning: ISO C90 forbids mixed declarations and code
node_to_cpumask_ptr(cpumask, pgdat->node_id), has a side-effect: it
defines the 'cpumask' local variable as well, so it has to go into
the variable definition section.
Sidenote: it might make sense to make this purpose of these macros
more apparent, by naming them the standard way, such as:
DEFINE_node_to_cpumask_ptr(cpumask, pgdat->node_id);
(But that is outside the scope of this patch.)
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mike Travis <travis@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The __GFP_FS annotations fail to build with CONFIG_LOCKDEP=y,
CONFIG_PROVE_LOCKING=n, ammend that.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Avoid confusion and clearly state lock debugging got disabled.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Arnd pointed out we have the stringify macro magic already in-kernel.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Remove the manual state iteration thingy.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Generic, states independent, get_user_chars().
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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there's too much repetition of code..
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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re-add some of the comments that got lost in the refactoring.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Now that we have nice numerical relations for the states, remove the macro
magics.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Now what its only two functions, they again look rather similar.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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These two are also remakably similar
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The _READ helpers show remarkable similarity, merge them.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Kill another argument
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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take away another parameter
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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In order to unify them, take some arguments away
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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split mark_lock_irq() into 4 simple helper functions
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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generate the usage strings
XXX capital invasion :-(
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Generate the state bit definitions from the lockdep_states.h file.
Also, move LOCK_USED to last, so that the
USED_IN
USED_IN_READ
ENABLED
ENABLED_READ
states are nicely bit aligned -- we're going to use that property
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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For convenience later.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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remove the state iteration
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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remove the explicit state iteration
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Introduce a header file to generate all the states from.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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s/HELD_OVER/ENABLED/g
so that its similar to the hard and soft-irq names.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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s/\(LOCKF\?_ENABLED_[^ ]*\)S\(_READ\)\?\>/\1\2/g
So that the USED_IN and ENABLED have the same names.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Here is another version, with the incremental patch rolled up, and
added reclaim context annotation to kswapd, and allocation tracing
to slab allocators (which may only ever reach the page allocator
in rare cases, so it is good to put annotations here too).
Haven't tested this version as such, but it should be getting closer
to merge worthy ;)
--
After noticing some code in mm/filemap.c accidentally perform a __GFP_FS
allocation when it should not have been, I thought it might be a good idea to
try to catch this kind of thing with lockdep.
I coded up a little idea that seems to work. Unfortunately the system has to
actually be in __GFP_FS page reclaim, then take the lock, before it will mark
it. But at least that might still be some orders of magnitude more common
(and more debuggable) than an actual deadlock condition, so we have some
improvement I hope (the concept is no less complete than discovery of a lock's
interrupt contexts).
I guess we could even do the same thing with __GFP_IO (normal reclaim), and
even GFP_NOIO locks too... but filesystems will have the most locks and fiddly
code paths, so let's start there and see how it goes.
It *seems* to work. I did a quick test.
=================================
[ INFO: inconsistent lock state ]
2.6.28-rc6-00007-ged31348-dirty #26
---------------------------------
inconsistent {in-reclaim-W} -> {ov-reclaim-W} usage.
modprobe/8526 [HC0[0]:SC0[0]:HE1:SE1] takes:
(testlock){--..}, at: [<ffffffffa0020055>] brd_init+0x55/0x216 [brd]
{in-reclaim-W} state was registered at:
[<ffffffff80267bdb>] __lock_acquire+0x75b/0x1a60
[<ffffffff80268f71>] lock_acquire+0x91/0xc0
[<ffffffff8070f0e1>] mutex_lock_nested+0xb1/0x310
[<ffffffffa002002b>] brd_init+0x2b/0x216 [brd]
[<ffffffff8020903b>] _stext+0x3b/0x170
[<ffffffff80272ebf>] sys_init_module+0xaf/0x1e0
[<ffffffff8020c3fb>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff
irq event stamp: 3929
hardirqs last enabled at (3929): [<ffffffff8070f2b5>] mutex_lock_nested+0x285/0x310
hardirqs last disabled at (3928): [<ffffffff8070f089>] mutex_lock_nested+0x59/0x310
softirqs last enabled at (3732): [<ffffffff8061f623>] sk_filter+0x83/0xe0
softirqs last disabled at (3730): [<ffffffff8061f5b6>] sk_filter+0x16/0xe0
other info that might help us debug this:
1 lock held by modprobe/8526:
#0: (testlock){--..}, at: [<ffffffffa0020055>] brd_init+0x55/0x216 [brd]
stack backtrace:
Pid: 8526, comm: modprobe Not tainted 2.6.28-rc6-00007-ged31348-dirty #26
Call Trace:
[<ffffffff80265483>] print_usage_bug+0x193/0x1d0
[<ffffffff80266530>] mark_lock+0xaf0/0xca0
[<ffffffff80266735>] mark_held_locks+0x55/0xc0
[<ffffffffa0020000>] ? brd_init+0x0/0x216 [brd]
[<ffffffff802667ca>] trace_reclaim_fs+0x2a/0x60
[<ffffffff80285005>] __alloc_pages_internal+0x475/0x580
[<ffffffff8070f29e>] ? mutex_lock_nested+0x26e/0x310
[<ffffffffa0020000>] ? brd_init+0x0/0x216 [brd]
[<ffffffffa002006a>] brd_init+0x6a/0x216 [brd]
[<ffffffffa0020000>] ? brd_init+0x0/0x216 [brd]
[<ffffffff8020903b>] _stext+0x3b/0x170
[<ffffffff8070f8b9>] ? mutex_unlock+0x9/0x10
[<ffffffff8070f83d>] ? __mutex_unlock_slowpath+0x10d/0x180
[<ffffffff802669ec>] ? trace_hardirqs_on_caller+0x12c/0x190
[<ffffffff80272ebf>] sys_init_module+0xaf/0x1e0
[<ffffffff8020c3fb>] system_call_fastpath+0x16/0x1b
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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This modifies the timer code in a way to allow lockdep to detect
deadlocks resulting from a lock being taken in the timer function
as well as around the del_timer_sync() call.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
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Conflicts:
fs/btrfs/locking.c
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Mutexes now spin internally and the btrfs spin is no longer required for
performance.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Spin more agressively. This is less fair but also markedly faster.
The numbers:
* dbench 50 (higher is better):
spin 1282MB/s
v10 548MB/s
v10 no wait 1868MB/s
* 4k creates (numbers in files/second higher is better):
spin avg 200.60 median 193.20 std 19.71 high 305.93 low 186.82
v10 avg 180.94 median 175.28 std 13.91 high 229.31 low 168.73
v10 no wait avg 232.18 median 222.38 std 22.91 high 314.66 low 209.12
* File stats (numbers in seconds, lower is better):
spin 2.27s
v10 5.1s
v10 no wait 1.6s
( The source changes are smaller than they look, I just moved the
need_resched checks in __mutex_lock_common after the cmpxchg. )
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Change mutex contention behaviour such that it will sometimes busy wait on
acquisition - moving its behaviour closer to that of spinlocks.
This concept got ported to mainline from the -rt tree, where it was originally
implemented for rtmutexes by Steven Rostedt, based on work by Gregory Haskins.
Testing with Ingo's test-mutex application (http://lkml.org/lkml/2006/1/8/50)
gave a 345% boost for VFS scalability on my testbox:
# ./test-mutex-shm V 16 10 | grep "^avg ops"
avg ops/sec: 296604
# ./test-mutex-shm V 16 10 | grep "^avg ops"
avg ops/sec: 85870
The key criteria for the busy wait is that the lock owner has to be running on
a (different) cpu. The idea is that as long as the owner is running, there is a
fair chance it'll release the lock soon, and thus we'll be better off spinning
instead of blocking/scheduling.
Since regular mutexes (as opposed to rtmutexes) do not atomically track the
owner, we add the owner in a non-atomic fashion and deal with the races in
the slowpath.
Furthermore, to ease the testing of the performance impact of this new code,
there is means to disable this behaviour runtime (without having to reboot
the system), when scheduler debugging is enabled (CONFIG_SCHED_DEBUG=y),
by issuing the following command:
# echo NO_OWNER_SPIN > /debug/sched_features
This command re-enables spinning again (this is also the default):
# echo OWNER_SPIN > /debug/sched_features
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The problem is that dropping the spinlock right before schedule is a voluntary
preemption point and can cause a schedule, right after which we schedule again.
Fix this inefficiency by keeping preemption disabled until we schedule, do this
by explicity disabling preemption and providing a schedule() variant that
assumes preemption is already disabled.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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