Hugh says:
"The only significant loser, I think, would be page reclaim (when
concurrent with truncation): could spin for a long time waiting for
the i_mmap_mutex it expects would soon be dropped? "
Counter points:
- cpu contention makes the spin stop (need_resched())
- zap pages should be freeing pages at a higher rate than reclaim
ever can
I think the simplification of the truncate code is definitely worth it.
Effectively reverts: 2aa15890f3 ("mm: prevent concurrent
unmap_mapping_range() on the same inode") and takes out the code that
caused its problem.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In order to convert i_mmap_lock to a mutex we need a mutex equivalent to
spin_lock_nest_lock(), thus provide the mutex_lock_nest_lock() annotation.
As with spin_lock_nest_lock(), mutex_lock_nest_lock() allows annotation of
the locking pattern where an outer lock serializes the acquisition order
of nested locks. That is, if every time you lock multiple locks A, say A1
and A2 you first acquire N, the order of acquiring A1 and A2 is
irrelevant.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Tony Luck <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some of the kerneldoc comments in kernel/power/hibernate.c are
outdated and some of them don't adhere to the kernel's standards.
Update them and make them look in a consistent way.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
All architectures supporting hibernation define
arch_prepare_suspend() as an empty function, so remove it.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (43 commits)
TOMOYO: Fix wrong domainname validation.
SELINUX: add /sys/fs/selinux mount point to put selinuxfs
CRED: Fix load_flat_shared_library() to initialise bprm correctly
SELinux: introduce path_has_perm
flex_array: allow 0 length elements
flex_arrays: allow zero length flex arrays
flex_array: flex_array_prealloc takes a number of elements, not an end
SELinux: pass last path component in may_create
SELinux: put name based create rules in a hashtable
SELinux: generic hashtab entry counter
SELinux: calculate and print hashtab stats with a generic function
SELinux: skip filename trans rules if ttype does not match parent dir
SELinux: rename filename_compute_type argument to *type instead of *con
SELinux: fix comment to state filename_compute_type takes an objname not a qstr
SMACK: smack_file_lock can use the struct path
LSM: separate LSM_AUDIT_DATA_DENTRY from LSM_AUDIT_DATA_PATH
LSM: split LSM_AUDIT_DATA_FS into _PATH and _INODE
SELINUX: Make selinux cache VFS RCU walks safe
SECURITY: Move exec_permission RCU checks into security modules
SELinux: security_read_policy should take a size_t not ssize_t
...
* 'for-2.6.40' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu: Unify input section names
percpu: Avoid extra NOP in percpu_cmpxchg16b_double
percpu: Cast away printk format warning
percpu: Always align percpu output section to PAGE_SIZE
Fix up fairly trivial conflict in arch/x86/include/asm/percpu.h as per Tejun
Ben Nagy reported a scalability problem with KVM/QEMU that hit very hard
a single spinlock (idr_lock) in posix-timers code, on its 48 core
machine.
Even on a 16 cpu machine (2x4x2), a single test can show 98% of cpu time
used in ticket_spin_lock, from lock_timer
Ref: http://www.spinics.net/lists/kvm/msg51526.html
Switching to RCU is quite easy, IDR being already RCU ready. idr_lock
should be locked only for an insert/delete, not a lookup.
Benchmark on a 2x4x2 machine, 16 processes calling timer_gettime().
Before :
real 1m18.669s
user 0m1.346s
sys 1m17.180s
After :
real 0m3.296s
user 0m1.366s
sys 0m1.926s
Reported-by: Ben Nagy <ben@iagu.net>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Ben Nagy <ben@iagu.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Richard Cochran <richard.cochran@omicron.at>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf tools: Fix sample type size calculation in 32 bits archs
profile: Use vzalloc() rather than vmalloc() & memset()
We try to enforce it by using -Wstrict-prototypes, but apparently they
sometimes get through. Introduced by 4eec42f392 ("watchdog: Change
the default timeout and configure nmi watchdog period based").
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This build warning slipped through:
kernel/watchdog.c:102: warning: function declaration isn't a prototype
As reported by Stephen Rothwell.
Also address an unused variable warning that GCC 4.6.0 reports:
we cannot do anything about failed watchdog ops during CPU hotplug
(it's not serious enough to return an error from the notifier),
so ignore them.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Mandeep Singh Baines <msb@chromium.org>
Cc: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20110524134129.8da27016.sfr@canb.auug.org.au
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20110517071642.GF22305@elte.hu>
Some comments in the core hibernate code are outdated, some aren't
necessary any more and at least one of them is plain wrong. Remove
those comments or update them.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* 'staging-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6: (970 commits)
staging: usbip: replace usbip_u{dbg,err,info} and printk with dev_ and pr_
staging:iio: Trivial kconfig reorganization and uniformity improvements.
staging:iio:documenation partial update.
staging:iio: use pollfunc allocation helpers in remaining drivers.
staging:iio:max1363 misc cleanups and use of for_each_bit_set to simplify event code spitting out.
staging:iio: implement an iio_info structure to take some of the constant elements out of iio_dev.
staging:iio:meter:ade7758: Use private data space from iio_allocate_device
staging:iio:accel:lis3l02dq make write_reg_8 take value not a pointer to value.
staging:iio: ring core cleanups + check if read_last available in lis3l02dq
staging:iio:core cleanup: squash tiny wrappers and use dev_set_name to handle creation of event interface name.
staging:iio: poll func allocation clean up.
staging:iio:ad7780 trivial unused header cleanup.
staging:iio:adc: AD7780: Use private data space from iio_allocate_device + trivial fixes
staging:iio:adc:AD7780: Convert to new channel registration method
staging:iio:adc: AD7606: Drop dev_data in favour of iio_priv()
staging:iio:adc: AD7606: Consitently use indio_dev
staging:iio: Rip out helper for software rings.
staging:iio:adc:AD7298: Use private data space from iio_allocate_device
staging:iio: rationalization of different buffer implementation hooks.
staging:iio:imu:adis16400 avoid allocating rx, tx, and state separately from iio_dev.
...
Fix up trivial conflicts in
- drivers/staging/intel_sst/intelmid.c: patches applied in both branches
- drivers/staging/rt2860/common/cmm_data_{pci,usb}.c: removed vs spelling
- drivers/staging/usbip/vhci_sysfs.c: trivial header file inclusion
* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
hrtimers: Reorder clock bases
hrtimers: Avoid touching inactive timer bases
hrtimers: Make struct hrtimer_cpu_base layout less stupid
timerfd: Manage cancelable timers in timerfd
clockevents: Move C3 stop test outside lock
alarmtimer: Drop device refcount after rtc_open()
alarmtimer: Check return value of class_find_device()
timerfd: Allow timers to be cancelled when clock was set
hrtimers: Prepare for cancel on clock was set timers
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf tools: Fix sample size bit operations
perf tools: Fix ommitted mmap data update on remap
watchdog: Change the default timeout and configure nmi watchdog period based on watchdog_thresh
watchdog: Disable watchdog when thresh is zero
watchdog: Only disable/enable watchdog if neccessary
watchdog: Fix rounding bug in get_sample_period()
perf tools: Propagate event parse error handling
perf tools: Robustify dynamic sample content fetch
perf tools: Pre-check sample size before parsing
perf tools: Move evlist sample helpers to evlist area
perf tools: Remove junk code in mmap size handling
perf tools: Check we are able to read the event size on mmap
* '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
...
The ordering of the clock bases is historical due to the
CLOCK_REALTIME and CLOCK_MONOTONIC constants. Now the hrtimer bases
have their own enumeration due to the gap between CLOCK_MONOTONIC and
CLOCK_BOOTTIME. So we can be more clever as most timers end up on the
CLOCK_MONOTONIC base due to the virtue of POSIX declaring that
relative CLOCK_REALTIME timers are not affected by time changes. In
desktop environments this is slowly changing as applications switch to
absolute timers, but I've observed empty CLOCK_REALTIME bases often
enough. There is no performance penalty or overhead when
CLOCK_REALTIME timers are active, but in case they are not we don't
skip over a full cache line.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
Instead of iterating over all possible timer bases avoid it by marking
the active bases in the cpu base.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
Peter is concerned about the extra scan of CLOCK_REALTIME_COS in the
timer interrupt. Yes, I did not think about it, because the solution
was so elegant. I didn't like the extra list in timerfd when it was
proposed some time ago, but with a rcu based list the list walk it's
less horrible than the original global lock, which was held over the
list iteration.
Requested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
Before the conversion of the NMI watchdog to perf event, the
watchdog timeout was 5 seconds. Now it is 60 seconds. For my
particular application, netbooks, 5 seconds was a better
timeout. With a short timeout, we catch faults earlier and are
able to send back a panic. With a 60 second timeout, the user is
unlikely to wait and will instead hit the power button, causing
us to lose the panic info.
This change configures the NMI period to watchdog_thresh and
sets the softlockup_thresh to watchdog_thresh * 2. In addition,
watchdog_thresh was reduced to 10 seconds as suggested by Ingo
Molnar.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1306127423-3347-4-git-send-email-msb@chromium.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20110517071642.GF22305@elte.hu>
This restores the previous behavior of softlock_thresh.
Currently, setting watchdog_thresh to zero causes the watchdog
kthreads to consume a lot of CPU.
In addition, the logic of proc_dowatchdog_thresh and
proc_dowatchdog_enabled has been factored into proc_dowatchdog.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1306127423-3347-3-git-send-email-msb@chromium.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <20110517071018.GE22305@elte.hu>
Don't take any action on an unsuccessful write to /proc.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1306127423-3347-2-git-send-email-msb@chromium.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In get_sample_period(), softlockup_thresh is integer divided by
5 before the multiplication by NSEC_PER_SEC. This results in
softlockup_thresh being rounded down to the nearest integer
multiple of 5.
For example, a softlockup_thresh of 4 rounds down to 0.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/1306127423-3347-1-git-send-email-msb@chromium.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next-2.6: (28 commits)
sparc32: fix build, fix missing cpu_relax declaration
SCHED_TTWU_QUEUE is not longer needed since sparc32 now implements IPI
sparc32,leon: Remove unnecessary page_address calls in LEON DMA API.
sparc: convert old cpumask API into new one
sparc32, sun4d: Implemented SMP IPIs support for SUN4D machines
sparc32, sun4m: Implemented SMP IPIs support for SUN4M machines
sparc32,leon: Implemented SMP IPIs for LEON CPU
sparc32: implement SMP IPIs using the generic functions
sparc32,leon: SMP power down implementation
sparc32,leon: added some SMP comments
sparc: add {read,write}*_be routines
sparc32,leon: don't rely on bootloader to mask IRQs
sparc32,leon: operate on boot-cpu IRQ controller registers
sparc32: always define boot_cpu_id
sparc32: removed unused code, implemented by generic code
sparc32: avoid build warning at mm/percpu.c:1647
sparc32: always register a PROM based early console
sparc32: probe for cpu info only during startup
sparc: consolidate show_cpuinfo in cpu.c
sparc32,leon: implement genirq CPU affinity
...
When building with:
CONFIG_64BIT=y
CONFIG_MIPS32_COMPAT=y
CONFIG_COMPAT=y
CONFIG_MIPS32_O32=y
CONFIG_MIPS32_N32=y
CONFIG_SYSVIPC is not set
(and implicitly: CONFIG_SYSVIPC_COMPAT is not set)
the final link fails with unresolved symbols for:
compat_sys_semctl, compat_sys_msgsnd, compat_sys_msgrcv,
compat_sys_shmctl, compat_sys_msgctl, compat_sys_semtimedop
The fix is to add cond_syscall declarations for all syscalls in
ipc/compat.c
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1446 commits)
macvlan: fix panic if lowerdev in a bond
tg3: Add braces around 5906 workaround.
tg3: Fix NETIF_F_LOOPBACK error
macvlan: remove one synchronize_rcu() call
networking: NET_CLS_ROUTE4 depends on INET
irda: Fix error propagation in ircomm_lmp_connect_response()
irda: Kill set but unused variable 'bytes' in irlan_check_command_param()
irda: Kill set but unused variable 'clen' in ircomm_connect_indication()
rxrpc: Fix set but unused variable 'usage' in rxrpc_get_transport()
be2net: Kill set but unused variable 'req' in lancer_fw_download()
irda: Kill set but unused vars 'saddr' and 'daddr' in irlan_provider_connect_indication()
atl1c: atl1c_resume() is only used when CONFIG_PM_SLEEP is defined.
rxrpc: Fix set but unused variable 'usage' in rxrpc_get_peer().
rxrpc: Kill set but unused variable 'local' in rxrpc_UDP_error_handler()
rxrpc: Kill set but unused variable 'sp' in rxrpc_process_connection()
rxrpc: Kill set but unused variable 'sp' in rxrpc_rotate_tx_window()
pkt_sched: Kill set but unused variable 'protocol' in tc_classify()
isdn: capi: Use pr_debug() instead of ifdefs.
tg3: Update version to 3.119
tg3: Apply rx_discards fix to 5719/5720
...
Fix up trivial conflicts in arch/x86/Kconfig and net/mac80211/agg-tx.c
as per Davem.
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
MAINTAINERS: Add drivers/clocksource to TIMEKEEPING
clockevents/source: Use u64 to make 32bit happy
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
extable, core_kernel_data(): Make sure all archs define _sdata
core_kernel_data(): Fix architectures that do not define _sdata
Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit e66eed651f ("list: remove prefetching from regular list
iterators") removed the include of prefetch.h from list.h, which
uncovered several cases that had apparently relied on that rather
obscure header file dependency.
So this fixes things up a bit, using
grep -L linux/prefetch.h $(git grep -l '[^a-z_]prefetchw*(' -- '*.[ch]')
grep -L 'prefetchw*(' $(git grep -l 'linux/prefetch.h' -- '*.[ch]')
to guide us in finding files that either need <linux/prefetch.h>
inclusion, or have it despite not needing it.
There are more of them around (mostly network drivers), but this gets
many core ones.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce SCHED_LOAD_RESOLUTION, which scales is added to
SCHED_LOAD_SHIFT and increases the resolution of
SCHED_LOAD_SCALE. This patch sets the value of
SCHED_LOAD_RESOLUTION to 10, scaling up the weights for all
sched entities by a factor of 1024. With this extra resolution,
we can handle deeper cgroup hiearchies and the scheduler can do
better shares distribution and load load balancing on larger
systems (especially for low weight task groups).
This does not change the existing user interface, the scaled
weights are only used internally. We do not modify
prio_to_weight values or inverses, but use the original weights
when calculating the inverse which is used to scale execution
time delta in calc_delta_mine(). This ensures we do not lose
accuracy when accounting time to the sched entities. Thanks to
Nikunj Dadhania for fixing an bug in c_d_m() that broken fairness.
Below is some analysis of the performance costs/improvements of
this patch.
1. Micro-arch performance costs:
Experiment was to run Ingo's pipe_test_100k 200 times with the
task pinned to one cpu. I measured instruction, cycles and
stalled-cycles for the runs. See:
http://thread.gmane.org/gmane.linux.kernel/1129232/focus=1129389
for more info.
-tip (baseline):
Performance counter stats for '/root/load-scale/pipe-test-100k' (200 runs):
964,991,769 instructions # 0.82 insns per cycle
# 0.33 stalled cycles per insn
# ( +- 0.05% )
1,171,186,635 cycles # 0.000 GHz ( +- 0.08% )
306,373,664 stalled-cycles-backend # 26.16% backend cycles idle ( +- 0.28% )
314,933,621 stalled-cycles-frontend # 26.89% frontend cycles idle ( +- 0.34% )
1.122405684 seconds time elapsed ( +- 0.05% )
-tip+patches:
Performance counter stats for './load-scale/pipe-test-100k' (200 runs):
963,624,821 instructions # 0.82 insns per cycle
# 0.33 stalled cycles per insn
# ( +- 0.04% )
1,175,215,649 cycles # 0.000 GHz ( +- 0.08% )
315,321,126 stalled-cycles-backend # 26.83% backend cycles idle ( +- 0.28% )
316,835,873 stalled-cycles-frontend # 26.96% frontend cycles idle ( +- 0.29% )
1.122238659 seconds time elapsed ( +- 0.06% )
With this patch, instructions decrease by ~0.10% and cycles
increase by 0.27%. This doesn't look statistically significant.
The number of stalled cycles in the backend increased from
26.16% to 26.83%. This can be attributed to the shifts we do in
c_d_m() and other places. The fraction of stalled cycles in the
frontend remains about the same, at 26.96% compared to 26.89% in -tip.
2. Balancing low-weight task groups
Test setup: run 50 tasks with random sleep/busy times (biased
around 100ms) in a low weight container (with cpu.shares = 2).
Measure %idle as reported by mpstat over a 10s window.
-tip (baseline):
06:47:48 PM CPU %usr %nice %sys %iowait %irq %soft %steal %guest %idle intr/s
06:47:49 PM all 94.32 0.00 0.06 0.00 0.00 0.00 0.00 0.00 5.62 15888.00
06:47:50 PM all 94.57 0.00 0.62 0.00 0.00 0.00 0.00 0.00 4.81 16180.00
06:47:51 PM all 94.69 0.00 0.06 0.00 0.00 0.00 0.00 0.00 5.25 15966.00
06:47:52 PM all 95.81 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4.19 16053.00
06:47:53 PM all 94.88 0.06 0.00 0.00 0.00 0.00 0.00 0.00 5.06 15984.00
06:47:54 PM all 93.31 0.00 0.00 0.00 0.00 0.00 0.00 0.00 6.69 15806.00
06:47:55 PM all 94.19 0.00 0.06 0.00 0.00 0.00 0.00 0.00 5.75 15896.00
06:47:56 PM all 92.87 0.00 0.00 0.00 0.00 0.00 0.00 0.00 7.13 15716.00
06:47:57 PM all 94.88 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5.12 15982.00
06:47:58 PM all 95.44 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4.56 16075.00
Average: all 94.49 0.01 0.08 0.00 0.00 0.00 0.00 0.00 5.42 15954.60
-tip+patches:
06:47:03 PM CPU %usr %nice %sys %iowait %irq %soft %steal %guest %idle intr/s
06:47:04 PM all 100.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 16630.00
06:47:05 PM all 99.69 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.31 16580.20
06:47:06 PM all 99.69 0.00 0.06 0.00 0.00 0.00 0.00 0.00 0.25 16596.00
06:47:07 PM all 99.20 0.00 0.74 0.00 0.00 0.06 0.00 0.00 0.00 17838.61
06:47:08 PM all 100.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 16540.00
06:47:09 PM all 100.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 16575.00
06:47:10 PM all 100.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 16614.00
06:47:11 PM all 99.94 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.06 16588.00
06:47:12 PM all 99.94 0.00 0.06 0.00 0.00 0.00 0.00 0.00 0.00 16593.00
06:47:13 PM all 99.94 0.00 0.06 0.00 0.00 0.00 0.00 0.00 0.00 16551.00
Average: all 99.84 0.00 0.09 0.00 0.00 0.01 0.00 0.00 0.06 16711.58
We see an improvement in idle% on the system (drops from 5.42% on -tip to 0.06%
with the patches).
We see an improvement in idle% on the system (drops from 5.42%
on -tip to 0.06% with the patches).
Signed-off-by: Nikhil Rao <ncrao@google.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com>
Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Cc: Stephan Barwolf <stephan.baerwolf@tu-ilmenau.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1305754668-18792-1-git-send-email-ncrao@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
SCHED_LOAD_SCALE is used to increase nice resolution and to
scale cpu_power calculations in the scheduler. This patch
introduces SCHED_POWER_SCALE and converts all uses of
SCHED_LOAD_SCALE for scaling cpu_power to use SCHED_POWER_SCALE
instead.
This is a preparatory patch for increasing the resolution of
SCHED_LOAD_SCALE, and there is no need to increase resolution
for cpu_power calculations.
Signed-off-by: Nikhil Rao <ncrao@google.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com>
Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Cc: Stephan Barwolf <stephan.baerwolf@tu-ilmenau.de>
Cc: Mike Galbraith <efault@gmx.de>
Link: http://lkml.kernel.org/r/1305738580-9924-3-git-send-email-ncrao@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Avoid using long repetitious names; make this simpler and nicer
to read. No functional change introduced in this patch.
Signed-off-by: Nikhil Rao <ncrao@google.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com>
Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Cc: Stephan Barwolf <stephan.baerwolf@tu-ilmenau.de>
Cc: Mike Galbraith <efault@gmx.de>
Link: http://lkml.kernel.org/r/1305738580-9924-2-git-send-email-ncrao@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
A new utility function (core_kernel_data()) is used to determine if a
passed in address is part of core kernel data or not. It may or may not
return true for RO data, but this utility must work for RW data.
Thus both _sdata and _edata must be defined and continuous,
without .init sections that may later be freed and replaced by
volatile memory (memory that can be freed).
This utility function is used to determine if data is safe from
ever being freed. Thus it should return true for all RW global
data that is not in a module or has been allocated, or false
otherwise.
Also change core_kernel_data() back to the more precise _sdata condition
and document the function.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Hirokazu Takata <takata@linux-m32r.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: JamesE.J.Bottomley <jejb@parisc-linux.org>
Link: http://lkml.kernel.org/r/1305855298.1465.19.camel@gandalf.stny.rr.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
----
arch/alpha/kernel/vmlinux.lds.S | 1 +
arch/m32r/kernel/vmlinux.lds.S | 1 +
arch/m68k/kernel/vmlinux-std.lds | 2 ++
arch/m68k/kernel/vmlinux-sun3.lds | 1 +
arch/mips/kernel/vmlinux.lds.S | 1 +
arch/parisc/kernel/vmlinux.lds.S | 3 +++
kernel/extable.c | 12 +++++++++++-
7 files changed, 20 insertions(+), 1 deletion(-)
Merge reason: One pending commit was left in perf/core after Linus merged
perf/core - continue v2.6.40 work in the perf/urgent reason.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This change adds support for /proc/sys/debug/exception-trace to tile.
Like x86 and sparc, by default it is set to "1", generating a one-line
printk whenever a user process crashes. By setting it to "2", we get
a much more complete userspace diagnostic at crash time, including
a user-space backtrace, register dump, and memory dump around the
address of the crash.
Some vestiges of the Tilera-internal version of this support are
removed with this patch (the show_crashinfo variable and the
arch_coredump_signal function). We retain a "crashinfo" boot parameter
which allows you to set the boot-time value of exception-trace.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (44 commits)
debugfs: Silence DEBUG_STRICT_USER_COPY_CHECKS=y warning
sysfs: remove "last sysfs file:" line from the oops messages
drivers/base/memory.c: fix warning due to "memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION"
memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION
SYSFS: Fix erroneous comments for sysfs_update_group().
driver core: remove the driver-model structures from the documentation
driver core: Add the device driver-model structures to kerneldoc
Translated Documentation/email-clients.txt
RAW driver: Remove call to kobject_put().
reboot: disable usermodehelper to prevent fs access
efivars: prevent oops on unload when efi is not enabled
Allow setting of number of raw devices as a module parameter
Introduce CONFIG_GOOGLE_FIRMWARE
driver: Google Memory Console
driver: Google EFI SMI
x86: Better comments for get_bios_ebda()
x86: get_bios_ebda_length()
misc: fix ti-st build issues
params.c: Use new strtobool function to process boolean inputs
debugfs: move to new strtobool
...
Fix up trivial conflicts in fs/debugfs/file.c due to the same patch
being applied twice, and an unrelated cleanup nearby.
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
hrtimer: Make lookup table const
RTC: Disable CONFIG_RTC_CLASS from being built as a module
timers: Fix alarmtimer build issues when CONFIG_RTC_CLASS=n
timers: Remove delayed irqwork from alarmtimers implementation
timers: Improve alarmtimer comments and minor fixes
timers: Posix interface for alarm-timers
timers: Introduce in-kernel alarm-timer interface
timers: Add rb_init_node() to allow for stack allocated rb nodes
time: Add timekeeping_inject_sleeptime
* 'timers-clockevents-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: hpet: Cleanup the clockevents init and register code
x86: Convert PIT to clockevents_config_and_register()
clockevents: Provide interface to reconfigure an active clock event device
clockevents: Provide combined configure and register function
clockevents: Restructure clock_event_device members
clocksource: Get rid of the hardcoded 5 seconds sleep time limit
clocksource: Restructure clocksource struct members
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (60 commits)
sched: Fix and optimise calculation of the weight-inverse
sched: Avoid going ahead if ->cpus_allowed is not changed
sched, rt: Update rq clock when unthrottling of an otherwise idle CPU
sched: Remove unused parameters from sched_fork() and wake_up_new_task()
sched: Shorten the construction of the span cpu mask of sched domain
sched: Wrap the 'cfs_rq->nr_spread_over' field with CONFIG_SCHED_DEBUG
sched: Remove unused 'this_best_prio arg' from balance_tasks()
sched: Remove noop in alloc_rt_sched_group()
sched: Get rid of lock_depth
sched: Remove obsolete comment from scheduler_tick()
sched: Fix sched_domain iterations vs. RCU
sched: Next buddy hint on sleep and preempt path
sched: Make set_*_buddy() work on non-task entities
sched: Remove need_migrate_task()
sched: Move the second half of ttwu() to the remote cpu
sched: Restructure ttwu() some more
sched: Rename ttwu_post_activation() to ttwu_do_wakeup()
sched: Remove rq argument from ttwu_stat()
sched: Remove rq->lock from the first half of ttwu()
sched: Drop rq->lock from sched_exec()
...
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: Fix rt_rq runtime leakage bug
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (107 commits)
perf stat: Add more cache-miss percentage printouts
perf stat: Add -d -d and -d -d -d options to show more CPU events
ftrace/kbuild: Add recordmcount files to force full build
ftrace: Add self-tests for multiple function trace users
ftrace: Modify ftrace_set_filter/notrace to take ops
ftrace: Allow dynamically allocated function tracers
ftrace: Implement separate user function filtering
ftrace: Free hash with call_rcu_sched()
ftrace: Have global_ops store the functions that are to be traced
ftrace: Add ops parameter to ftrace_startup/shutdown functions
ftrace: Add enabled_functions file
ftrace: Use counters to enable functions to trace
ftrace: Separate hash allocation and assignment
ftrace: Create a global_ops to hold the filter and notrace hashes
ftrace: Use hash instead for FTRACE_FL_FILTER
ftrace: Replace FTRACE_FL_NOTRACE flag with a hash of ignored functions
perf bench, x86: Add alternatives-asm.h wrapper
x86, 64-bit: Fix copy_[to/from]_user() checks for the userspace address limit
x86, mem: memset_64.S: Optimize memset by enhanced REP MOVSB/STOSB
x86, mem: memmove_64.S: Optimize memmove by enhanced REP MOVSB/STOSB
...
* '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/rafael/suspend-2.6: (34 commits)
PM: Introduce generic prepare and complete callbacks for subsystems
PM: Allow drivers to allocate memory from .prepare() callbacks safely
PM: Remove CONFIG_PM_VERBOSE
Revert "PM / Hibernate: Reduce autotuned default image size"
PM / Hibernate: Add sysfs knob to control size of memory for drivers
PM / Wakeup: Remove useless synchronize_rcu() call
kmod: always provide usermodehelper_disable()
PM / ACPI: Remove acpi_sleep=s4_nonvs
PM / Wakeup: Fix build warning related to the "wakeup" sysfs file
PM: Print a warning if firmware is requested when tasks are frozen
PM / Runtime: Rework runtime PM handling during driver removal
Freezer: Use SMP barriers
PM / Suspend: Do not ignore error codes returned by suspend_enter()
PM: Fix build issue in clock_ops.c for CONFIG_PM_RUNTIME unset
PM: Revert "driver core: platform_bus: allow runtime override of dev_pm_ops"
OMAP1 / PM: Use generic clock manipulation routines for runtime PM
PM: Remove sysdev suspend, resume and shutdown operations
PM / PowerPC: Use struct syscore_ops instead of sysdevs for PM
PM / UNICORE32: Use struct syscore_ops instead of sysdevs for PM
PM / AVR32: Use struct syscore_ops instead of sysdevs for PM
...
Some architectures such as Alpha do not define _sdata but _data:
kernel/built-in.o: In function `core_kernel_data':
kernel/extable.c:77: undefined reference to `_sdata'
So expand the scope of the data range to the text addresses too,
this might be more correct anyway because this way we can
cover readonly variables as well.
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-i878c8a0e0g0ep4v7i6vxnhz@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
move LSM-, credentials-, and keys-related files from Documentation/
to Documentation/security/,
add Documentation/security/00-INDEX, and
update all occurrences of Documentation/<moved_file>
to Documentation/security/<moved_file>.
This reverts commit e59fb3120b.
This reversion was due to (extreme) boot-time slowdowns on SPARC seen by
Yinghai Lu and on x86 by Ingo
.
This is a non-trivial reversion due to intervening commits.
Conflicts:
Documentation/RCU/trace.txt
kernel/rcutree.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Some ARM SoCs have clock event devices which have their frequency
modified due to frequency scaling. Provide an interface which allows
to reconfigure an active device. After reconfiguration reprogram the
current pending event.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: LAK <linux-arm-kernel@lists.infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Link: http://lkml.kernel.org/r/%3C20110518210136.437459958%40linutronix.de%3E
All clockevent devices have the same open coded initialization
functions. Provide an interface which does all necessary
initialization in the core code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Link: http://lkml.kernel.org/r/%3C20110518210136.331975870%40linutronix.de%3E
Slow clocksources can have a way longer sleep time than 5 seconds and
even fast ones can easily cope with 600 seconds and still maintain
proper accuracy.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Link: http://lkml.kernel.org/r/%3C20110518210136.109811585%40linutronix.de%3E
The function is_exported() with its helper function lookup_symbol() are used to
verify if a provided symbol is effectively exported by the kernel or by the
modules. Now that both have their symbols sorted we can replace a linear search
with a binary search which provide a considerably speed-up.
This work was supported by a hardware donation from the CE Linux Forum.
Signed-off-by: Alessio Igor Bogani <abogani@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Takes advantage of the order and locates symbols using binary search.
This work was supported by a hardware donation from the CE Linux Forum.
Signed-off-by: Alessio Igor Bogani <abogani@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Tested-by: Dirk Behme <dirk.behme@googlemail.com>
Instead of having a callback function for each symbol in the kernel,
have a callback for each array of symbols.
This eases the logic when we move to sorted symbols and binary search.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Alessio Igor Bogani <abogani@kernel.org>
Split the unprotect function into a function per section to make
the code more readable and add the missing static declaration.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
While debugging I stumbled over two problems in the code that protects module
pages.
First issue is that disabling the protection before freeing init or unload of
a module is not symmetric with the enablement. For instance, if pages are set
to RO the page range from module_core to module_core + core_ro_size is
protected. If a module is unloaded the page range from module_core to
module_core + core_size is set back to RW.
So pages that were not set to RO are also changed to RW.
This is not critical but IMHO it should be symmetric.
Second issue is that while set_memory_rw & set_memory_ro are used for
RO/RW changes only set_memory_nx is involved for NX/X. One would await that
the inverse function is called when the NX protection should be removed,
which is not the case here, unless I'm missing something.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reset mod->init_ro_size to zero after the init part of a module is unloaded.
Otherwise we need to check if module->init is NULL in the unprotect functions
in the next patch.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Fix function prototype to be ANSI-C compliant, consistent with other
function prototypes, addressing a sparse warning.
Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
On m68k natural alignment is 2-byte boundary but we are trying to
align structures in __modver section on sizeof(void *) boundary.
This causes trouble when we try to access elements in this section
in array-like fashion when create "version" attributes for built-in
modules.
Moreover, as DaveM said, we can't reliably put structures into
independent objects, put them into a special section, and then expect
array access over them (via the section boundaries) after linking the
objects together to just "work" due to variable alignment choices in
different situations. The only solution that seems to work reliably
is to make an array of plain pointers to the objects in question and
put those pointers in the special section.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Since users of the function tracer can now pick and choose which
functions they want to trace agnostically from other users of the
function tracer, we need to pass the ops struct to the ftrace_set_filter()
functions.
The functions ftrace_set_global_filter() and ftrace_set_global_notrace()
is added to keep the old filter functions which are used to modify
the generic function tracers.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Now that functions may be selected individually, it only makes sense
that we should allow dynamically allocated trace structures to
be traced. This will allow perf to allocate a ftrace_ops structure
at runtime and use it to pick and choose which functions that
structure will trace.
Note, a dynamically allocated ftrace_ops will always be called
indirectly instead of being called directly from the mcount in
entry.S. This is because there's no safe way to prevent mcount
from being preempted before calling the function, unless we
modify every entry.S to do so (not likely). Thus, dynamically allocated
functions will now be called by the ftrace_ops_list_func() that
loops through the ops that are allocated if there are more than
one op allocated at a time. This loop is protected with a
preempt_disable.
To determine if an ftrace_ops structure is allocated or not, a new
util function was added to the kernel/extable.c called
core_kernel_data(), which returns 1 if the address is between
_sdata and _edata.
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
ftrace_ops that are registered to trace functions can now be
agnostic to each other in respect to what functions they trace.
Each ops has their own hash of the functions they want to trace
and a hash to what they do not want to trace. A empty hash for
the functions they want to trace denotes all functions should
be traced that are not in the notrace hash.
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When a hash is modified and might be in use, we need to perform
a schedule RCU operation on it, as the hashes will soon be used
directly in the function tracer callback.
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This is a step towards each ops structure defining its own set
of functions to trace. As the current code with pid's and such
are specific to the global_ops, it is restructured to be used
with the global ops.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
In order to allow different ops to enable different functions,
the ftrace_startup() and ftrace_shutdown() functions need the
ops parameter passed to them.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Add the enabled_functions file that is used to show all the
functions that have been enabled for tracing as well as their
ref counts. This helps seeing if any function has been registered
and what functions are being traced.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Every function has its own record that stores the instruction
pointer and flags for the function to be traced. There are only
two flags: enabled and free. The enabled flag states that tracing
for the function has been enabled (actively traced), and the free
flag states that the record no longer points to a function and can
be used by new functions (loaded modules).
These flags are now moved to the MSB of the flags (actually just
the top 32bits). The rest of the bits (30 bits) are now used as
a ref counter. Everytime a tracer register functions to trace,
those functions will have its counter incremented.
When tracing is enabled, to determine if a function should be traced,
the counter is examined, and if it is non-zero it is set to trace.
When a ftrace_ops is registered to trace functions, its hashes
are examined. If the ftrace_ops filter_hash count is zero, then
all functions are set to be traced, otherwise only the functions
in the hash are to be traced. The exception to this is if a function
is also in the ftrace_ops notrace_hash. Then that function's counter
is not incremented for this ftrace_ops.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When filtering, allocate a hash to insert the function records.
After the filtering is complete, assign it to the ftrace_ops structure.
This allows the ftrace_ops structure to have a much smaller array of
hash buckets instead of wasting a lot of memory.
A read only empty_hash is created to be the minimum size that any ftrace_ops
can point to.
When a new hash is created, it has the following steps:
o Allocate a default hash.
o Walk the function records assigning the filtered records to the hash
o Allocate a new hash with the appropriate size buckets
o Move the entries from the default hash to the new hash.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Combine the filter and notrace hashes to be accessed by a single entity,
the global_ops. The global_ops is a ftrace_ops structure that is passed
to different functions that can read or modify the filtering of the
function tracer.
The ftrace_ops structure was modified to hold a filter and notrace
hashes so that later patches may allow each ftrace_ops to have its own
set of rules to what functions may be filtered.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When multiple users are allowed to have their own set of functions
to trace, having the FTRACE_FL_FILTER flag will not be enough to
handle the accounting of those users. Each user will need their own
set of functions.
Replace the FTRACE_FL_FILTER with a filter_hash instead. This is
temporary until the rest of the function filtering accounting
gets in.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
To prepare for the accounting system that will allow multiple users of
the function tracer, having the FTRACE_FL_NOTRACE as a flag in the
dyn_trace record does not make sense.
All ftrace_ops will soon have a hash of functions they should trace
and not trace. By making a global hash of functions not to trace makes
this easier for the transition.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Export handle_simple_irq, irq_modify_status, irq_alloc_descs,
irq_free_descs and generic_handle_irq to allow their usage in
modules. First user is IIO, which wants to be built modular, but needs
to be able to create irq chips, allocate and configure interrupt
descriptors and handle demultiplexing interrupts.
[ tglx: Moved the uninlinig of generic_handle_irq to a separate patch ]
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Link: http://lkml.kernel.org/r/%3C1305711544-505-1-git-send-email-jic23%40cam.ac.uk%3E
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
generic_handle_irq() is missing a NULL pointer check for the result of
irq_to_desc. This was a not a big problem, but we want to expose it to
drivers, so we better have sanity checks in place. Add a return value
as well, which indicates that the irq number was valid and the handler
was invoked.
Based on the pure code move from Jonathan Cameron.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jonathan Cameron <jic23@cam.ac.uk>
kernel/irq/ is only built when CONFIG_GENERIC_HARDIRQS=y. So making
code inside of kernel/irq/ conditional on CONFIG_GENERIC_HARDIRQS is
pointless.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If device drivers allocate substantial amounts of memory (above 1 MB)
in their hibernate .freeze() callbacks (or in their legacy suspend
callbcks during hibernation), the subsequent creation of hibernate
image may fail due to the lack of memory. This is the case, because
the drivers' .freeze() callbacks are executed after the hibernate
memory preallocation has been carried out and the preallocated amount
of memory may be too small to cover the new driver allocations.
Unfortunately, the drivers' .prepare() callbacks also are executed
after the hibernate memory preallocation has completed, so they are
not suitable for allocating additional memory either. Thus the only
way a driver can safely allocate memory during hibernation is to use
a hibernate/suspend notifier. However, the notifiers are called
before the freezing of user space and the drivers wanting to use them
for allocating additional memory may not know how much memory needs
to be allocated at that point.
To let device drivers overcome this difficulty rework the hibernation
sequence so that the memory preallocation is carried out after the
drivers' .prepare() callbacks have been executed, so that the
.prepare() callbacks can be used for allocating additional memory
to be used by the drivers' .freeze() callbacks. Update documentation
to match the new behavior of the code.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Now that we have CONFIG_DYNAMIC_DEBUG there is no need for yet
another flag causing dev_dbg() and pr_debug() statements in the
core PM code to produce output. Moreover, CONFIG_PM_VERBOSE
causes so much output to be generated that it's not really useful
and almost no one sets it.
References: https://bugzilla.kernel.org/show_bug.cgi?id=23182
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* power-domains:
PM: Fix build issue in clock_ops.c for CONFIG_PM_RUNTIME unset
PM: Revert "driver core: platform_bus: allow runtime override of dev_pm_ops"
OMAP1 / PM: Use generic clock manipulation routines for runtime PM
PM / Runtime: Generic clock manipulation rountines for runtime PM (v6)
PM / Runtime: Add subsystem data field to struct dev_pm_info
OMAP2+ / PM: move runtime PM implementation to use device power domains
PM / Platform: Use generic runtime PM callbacks directly
shmobile: Use power domains for platform runtime PM
PM: Export platform bus type's default PM callbacks
PM: Make power domain callbacks take precedence over subsystem ones
* syscore:
PM: Remove sysdev suspend, resume and shutdown operations
PM / PowerPC: Use struct syscore_ops instead of sysdevs for PM
PM / UNICORE32: Use struct syscore_ops instead of sysdevs for PM
PM / AVR32: Use struct syscore_ops instead of sysdevs for PM
PM / Blackfin: Use struct syscore_ops instead of sysdevs for PM
ARM / Samsung: Use struct syscore_ops for "core" power management
ARM / PXA: Use struct syscore_ops for "core" power management
ARM / SA1100: Use struct syscore_ops for "core" power management
ARM / Integrator: Use struct syscore_ops for core PM
ARM / OMAP: Use struct syscore_ops for "core" power management
ARM: Use struct syscore_ops instead of sysdevs for PM in common code
This reverts commit bea3864fb6
(PM / Hibernate: Reduce autotuned default image size), because users
are now able to resolve the issue this commit was supposed to address
in a different way (i.e. by using the new /sys/power/reserved_size
interface).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Martin reports that on his system hibernation occasionally fails due
to the lack of memory, because the radeon driver apparently allocates
too much of it during the device freeze stage. It turns out that the
amount of memory allocated by radeon during hibernation (and
presumably during system suspend too) depends on the utilization of
the GPU (e.g. hibernating while there are two KDE 4 sessions with
compositing enabled causes radeon to allocate more memory than for
one KDE 4 session).
In principle it should be possible to use image_size to make the
memory preallocation mechanism free enough memory for the radeon
driver, but in practice it is not easy to guess the right value
because of the way the preallocation code uses image_size. For this
reason, it seems reasonable to allow users to control the amount of
memory reserved for driver allocations made after the hibernate
preallocation, which currently is constant and amounts to 1 MB.
Introduce a new sysfs file, /sys/power/reserved_size, whose value
will be used as the amount of memory to reserve for the
post-preallocation reservations made by device drivers, in bytes.
For backwards compatibility, set its default (and initial) value to
the currently used number (1 MB).
References: https://bugzilla.kernel.org/show_bug.cgi?id=34102
Reported-and-tested-by: Martin Steigerwald <Martin@Lichtvoll.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
We need to prevent kernel-forked processes during system poweroff.
Such processes try to access the filesystem whose disks we are
trying to shutdown at the same time. This causes delays and exceptions
in the storage drivers.
A follow-up patch will add these calls and need usermodehelper_disable()
also on systems without suspend support.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Some drivers erroneously use request_firmware() from their ->resume()
(or ->thaw(), or ->restore()) callbacks, which is not going to work
unless the firmware has been built in. This causes system resume to
stall until the firmware-loading timeout expires, which makes users
think that the resume has failed and reboot their machines
unnecessarily. For this reason, make _request_firmware() print a
warning and return immediately with error code if it has been called
when tasks are frozen and it's impossible to start any new usermode
helpers.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Reviewed-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
The freezer processes are dealing with multiple threads running
simultaneously, and on a UP system, the memory reads/writes do
not need barriers to keep things in sync. These are only needed
on SMP systems, so use SMP barriers instead.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The current implementation of suspend-to-RAM returns 0 if there is an
error from suspend_enter(), because suspend_devices_and_enter() ignores
the return value from suspend_enter(). This patch addresses this issue
and properly keep the error return from suspend_enter() and let
suspend_devices_and_enter relay the error return.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
The first cpu which switches from periodic to oneshot mode switches
also the broadcast device into oneshot mode. The broadcast device
serves as a backup for per cpu timers which stop in deeper
C-states. To avoid starvation of the cpus which might be in idle and
depend on broadcast mode it marks the other cpus as broadcast active
and sets the brodcast expiry value of those cpus to the next tick.
The oneshot mode broadcast bit for the other cpus is sticky and gets
only cleared when those cpus exit idle. If a cpu was not idle while
the bit got set in consequence the bit prevents that the broadcast
device is armed on behalf of that cpu when it enters idle for the
first time after it switched to oneshot mode.
In most cases that goes unnoticed as one of the other cpus has usually
a timer pending which keeps the broadcast device armed with a short
timeout. Now if the only cpu which has a short timer active has the
bit set then the broadcast device will not be armed on behalf of that
cpu and will fire way after the expected timer expiry. In the case of
Christians bug report it took ~145 seconds which is about half of the
wrap around time of HPET (the limit for that device) due to the fact
that all other cpus had no timers armed which expired before the 145
seconds timeframe.
The solution is simply to clear the broadcast active bit
unconditionally when a cpu switches to oneshot mode after the first
cpu switched the broadcast device over. It's not idle at that point
otherwise it would not be executing that code.
[ I fundamentally hate that broadcast crap. Why the heck thought some
folks that when going into deep idle it's a brilliant concept to
switch off the last device which brings the cpu back from that
state? ]
Thanks to Christian for providing all the valuable debug information!
Reported-and-tested-by: Christian Hoffmann <email@christianhoffmann.info>
Cc: John Stultz <johnstul@us.ibm.com>
Link: http://lkml.kernel.org/r/%3Calpine.LFD.2.02.1105161105170.3078%40ionos%3E
Cc: stable@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If the inverse loadweight should be zero, function "calc_delta_mine"
calculates the inverse of "lw->weight" (in 32bit integer ops).
This calculation is actually a little bit impure (because it is
inverting something around "lw-weight"+1), especially when
"lw->weight" becomes smaller.
The correct inverse would be 1/lw->weight multiplied by
"WMULT_CONST" for fixcomma-scaling it into integers.
(So WMULT_CONST/lw->weight ...)
The old, impure algorithm took two divisions for inverting lw->weight,
the new, more exact one only takes one and an additional unlikely-if.
Signed-off-by: Stephan Baerwolf <stephan.baerwolf@tu-ilmenau.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-0pz0wnyalr4tk4ln11xwumdx@git.kernel.org
[ This could explain some aritmetical issues for small shares but nothing
concrete has been reported yet so we are not confident enough to queue
this up in sched/urgent and for -stable backport. But if anyone finds
this commit and sees it to fix some badness then we can certainly
change our mind! ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If cpumask_equal(&p->cpus_allowed, new_mask) is true, seems
there is no reason to prevent set_cpus_allowed_ptr() return
directly.
Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Acked-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20110509140705.GA2219@zhy
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If an RT task is awakened while it's rt_rq is throttled, the time between
wakeup/enqueue and unthrottle/selection may be accounted as rt_time
if the CPU is idle. Set rq->skip_clock_update negative upon throttle
release to tell put_prev_task() that we need a clock update.
Reported-by: Thomas Giesel <skoe@directbox.com>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1304059010.7472.1.camel@marge.simson.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch is to fix the real-time scheduler bug reported at:
https://lkml.org/lkml/2011/4/26/13
That is, when running multiple real-time threads on every logical CPUs
and then turning off one CPU, the kernel will bug at function
__disable_runtime().
Function __disable_runtime() bugs and reports leakage of rt_rq runtime.
The root cause is __disable_runtime() assumes it iterates through all
the existing rt_rq's while walking rq->leaf_rt_rq_list, which actually
contains only runnable rt_rq's. This problem also applies to
__enable_runtime() and print_rt_stats().
The patch is based on above analysis, appears to fix the problem, but is
only lightly tested.
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Cheng Xu <chengxu@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4DCE1F12.6040609@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Peter Zijlstra