03 Feb, 2011
1 commit
-
Currently the trace_event structures are placed in the _ftrace_events
section, and at link time, the linker makes one large array of all
the trace_event structures. On boot up, this array is read (much like
the initcall sections) and the events are processed.The problem is that there is no guarantee that gcc will place complex
structures nicely together in an array format. Two structures in the
same file may be placed awkwardly, because gcc has no clue that they
are suppose to be in an array.A hack was used previous to force the alignment to 4, to pack the
structures together. But this caused alignment issues with other
architectures (sparc).Instead of packing the structures into an array, the structures' addresses
are now put into the _ftrace_event section. As pointers are always the
natural alignment, gcc should always pack them tightly together
(otherwise initcall, extable, etc would also fail).By having the pointers to the structures in the section, we can still
iterate the trace_events without causing unnecessary alignment problems
with other architectures, or depending on the current behaviour of
gcc that will likely change in the future just to tick us kernel developers
off a little more.The _ftrace_event section is also moved into the .init.data section
as it is now only needed at boot up.Suggested-by: David Miller
Cc: Mathieu Desnoyers
Acked-by: David S. Miller
Signed-off-by: Steven Rostedt
16 Jan, 2011
1 commit
-
…linus' and 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
rcu: avoid pointless blocked-task warnings
rcu: demote SRCU_SYNCHRONIZE_DELAY from kernel-parameter status
rtmutex: Fix comment about why new_owner can be NULL in wake_futex_pi()* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, olpc: Add missing Kconfig dependencies
x86, mrst: Set correct APB timer IRQ affinity for secondary cpu
x86: tsc: Fix calibration refinement conditionals to avoid divide by zero
x86, ia64, acpi: Clean up x86-ism in drivers/acpi/numa.c* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
timekeeping: Make local variables static
time: Rename misnamed minsec argument of clocks_calc_mult_shift()* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: Remove syscall_exit_fields
tracing: Only process module tracepoints once
perf record: Add "nodelay" mode, disabled by default
perf sched: Fix list of events, dropping unsupported ':r' modifier
Revert "perf tools: Emit clearer message for sys_perf_event_open ENOENT return"
perf top: Fix annotate segv
perf evsel: Fix order of event list deletion
15 Jan, 2011
1 commit
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The commit:
9f987b3141f086de27832514aad9f50a53f754
tracing: Include module.h in define_trace.honly solved half the problem. If the trace/events/module.h header is
included at the time of define_trace.h (or in ftrace.h within it),
the module.h TRACE_SYSTEM will override the current TRACE_SYSTEM
macro.Since define_trace.h is included when CREATE_TRACE_POINTS is set,
and the first thing it does is to #undef CREATE_TRACE_POINTS,
by placing the module.h TRACE_SYSTEM inside a
#ifdef CREATE_TRACE_POINTS
we can prevent it from overriding the TRACE_SYSTEM that is
being processed, and still process the module.h tracepoints
when the module code defines CREATE_TRACE_POINTS and includes
the trace/events/module.h header.As with commit 9f987b3141, this is only an issue if module.h
is not included before the trace/events/.h file is
included, which (luckily) has not happened yet.Reported-by: Peter Zijlstra
Signed-off-by: Steven Rostedt
14 Jan, 2011
8 commits
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With compaction being used instead of lumpy reclaim, the name lumpy_mode
and associated variables is a bit misleading. Rename lumpy_mode to
reclaim_mode which is a better fit. There is no functional change.Signed-off-by: Mel Gorman
Cc: Andrea Arcangeli
Cc: KOSAKI Motohiro
Cc: Rik van Riel
Acked-by: Johannes Weiner
Cc: Andy Whitcroft
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Currently lumpy_mode is an enum and determines if lumpy reclaim is off,
syncronous or asyncronous. In preparation for using compaction instead of
lumpy reclaim, this patch converts the flags into a bitmap.Signed-off-by: Mel Gorman
Cc: Andrea Arcangeli
Cc: KOSAKI Motohiro
Cc: Rik van Riel
Cc: Johannes Weiner
Cc: Andy Whitcroft
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In preparation for a patches promoting the use of memory compaction over
lumpy reclaim, this patch adds trace points for memory compaction
activity. Using them, we can monitor the scanning activity of the
migration and free page scanners as well as the number and success rates
of pages passed to page migration.Signed-off-by: Mel Gorman
Cc: Andrea Arcangeli
Cc: KOSAKI Motohiro
Cc: Rik van Riel
Cc: Johannes Weiner
Cc: Andy Whitcroft
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This tracks when balance_dirty_pages() tries to wakeup the flusher thread
for background writeback (if it was not started already).Suggested-by: Christoph Hellwig
Signed-off-by: Wu Fengguang
Cc: Jan Kara
Cc: Johannes Weiner
Cc: Dave Chinner
Cc: Jan Engelhardt
Cc: Jens Axboe
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits)
block: ensure that completion error gets properly traced
blktrace: add missing probe argument to block_bio_complete
block cfq: don't use atomic_t for cfq_group
block cfq: don't use atomic_t for cfq_queue
block: trace event block fix unassigned field
block: add internal hd part table references
block: fix accounting bug on cross partition merges
kref: add kref_test_and_get
bio-integrity: mark kintegrityd_wq highpri and CPU intensive
block: make kblockd_workqueue smarter
Revert "sd: implement sd_check_events()"
block: Clean up exit_io_context() source code.
Fix compile warnings due to missing removal of a 'ret' variable
fs/block: type signature of major_to_index(int) to major_to_index(unsigned)
block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p)
cfq-iosched: don't check cfqg in choose_service_tree()
fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
cdrom: export cdrom_check_events()
sd: implement sd_check_events()
sr: implement sr_check_events()
... -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: (348 commits)
ALSA: hda - Fix NULL-derefence with a single mic in STAC auto-mic detection
ALSA: hda - Add missing NID 0x19 fixup for Sony VAIO
ALSA: hda - Fix ALC275 enable hardware EQ for SONY VAIO
ALSA: oxygen: fix Xonar DG input
ALSA: hda - Fix EAPD on Lenovo NB ALC269 to low
ALSA: hda - Fix missing EAPD for Acer 4930G
ALSA: hda: Disable 4/6 channels on some NVIDIA GPUs.
ALSA: hda - Add static_hdmi_pcm option to HDMI codec parser
ALSA: hda - Don't refer ELD when unplugged
ASoC: tpa6130a2: Fix compiler warning
ASoC: tlv320dac33: Add DAPM selection for LOM invert
ASoC: DMIC codec: Adding a generic DMIC codec
ALSA: snd-usb-us122l: Fix missing NULL checks
ALSA: snd-usb-us122l: Fix MIDI output
ASoC: soc-cache: Fix invalid memory access during snd_soc_lzo_cache_sync()
ASoC: Fix section mismatch in wm8995.c
ALSA: oxygen: add S/PDIF source selection for Claro cards
ALSA: oxygen: fix CD/MIDI for X-Meridian (2G)
ASoC: fix migor audio build
ALSA: include delay.h for msleep in Xonar DG support
... -
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6: (45 commits)
regulator: missing index in PTR_ERR() in isl6271a_probe()
regulator: Assign return value of mc13xxx_reg_rmw to ret
regulator: Add initial per-regulator debugfs support
regulator: Make regulator_has_full_constraints a bool
regulator: Clean up logging a bit
regulator: Optimise out noop voltage changes
regulator: Add API to re-apply voltage to hardware
regulator: Staticise non-exported functions in mc13892
regulator: Only notify voltage changes when they succeed
regulator: Provide a selector based set_voltage_sel() operation
regulator: Factor out voltage set operation into a separate function
regulator: Convert WM8994 to use get_voltage_sel()
regulator: Convert WM835x to use get_voltage_sel()
regulator: Allow modular build of mc13xxx-core
regulator: support PMIC mc13892
make mc13783 regulator code generic
Change the register name definitions for mc13783
mach-ux500: Updated and connected ab8500 regulator board configuration
regulators: Removed macros for initialization of ab8500 regulators
regulators: Added verbose debug messages to ab8500 regulators
... -
* 'kvm-updates/2.6.38' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (142 commits)
KVM: Initialize fpu state in preemptible context
KVM: VMX: when entering real mode align segment base to 16 bytes
KVM: MMU: handle 'map_writable' in set_spte() function
KVM: MMU: audit: allow audit more guests at the same time
KVM: Fetch guest cr3 from hardware on demand
KVM: Replace reads of vcpu->arch.cr3 by an accessor
KVM: MMU: only write protect mappings at pagetable level
KVM: VMX: Correct asm constraint in vmcs_load()/vmcs_clear()
KVM: MMU: Initialize base_role for tdp mmus
KVM: VMX: Optimize atomic EFER load
KVM: VMX: Add definitions for more vm entry/exit control bits
KVM: SVM: copy instruction bytes from VMCB
KVM: SVM: implement enhanced INVLPG intercept
KVM: SVM: enhance mov DR intercept handler
KVM: SVM: enhance MOV CR intercept handler
KVM: SVM: add new SVM feature bit names
KVM: cleanup emulate_instruction
KVM: move complete_insn_gp() into x86.c
KVM: x86: fix CR8 handling
KVM guest: Fix kvm clock initialization when it's configured out
...
12 Jan, 2011
6 commits
-
Provide some basic trace facilities to the regulator API. We generate
events on regulator enable, disable and voltage setting over the actual
hardware operations (which are assumed to be the expensive ones which
require interaction with the actual device). This is intended to facilitate
debug of the performance and behaviour with consumers allowing unified
traces to be generated including the regulator operations within the
context of the other components of the system.For enable we log the explicit delay for the voltage ramp separately to
the interaction with the hardware to highlight the time consumed in I/O.
We should add a similar delay for voltage changes, though there the
relatively small magnitude of the changes in the context of the I/O
costs makes it much less critical for most regulators.Only hardware interactions are currently traced as the primary focus is
on the performance and synchronisation of actual hardware interactions.
Additional tracepoints for debugging of the logical operations can be
added later if required.Signed-off-by: Mark Brown
Signed-off-by: Liam Girdwood -
Use 'DECLARE_EVENT_CLASS' to cleanup async_pf tracepoints
Acked-by: Gleb Natapov
Signed-off-by: Xiao Guangrong
Signed-off-by: Marcelo Tosatti -
Tracing 'async' and *pfn is useless, since 'async' is always true,
and '*pfn' is always "fault_pfn'We can trace 'gva' and 'gfn' instead, it can help us to see the
life-cycle of an async_pfSigned-off-by: Xiao Guangrong
Signed-off-by: Marcelo Tosatti -
Add tracepoint for userspace exit.
Signed-off-by: Gleb Natapov
Signed-off-by: Marcelo Tosatti -
Send async page fault to a PV guest if it accesses swapped out memory.
Guest will choose another task to run upon receiving the fault.Allow async page fault injection only when guest is in user mode since
otherwise guest may be in non-sleepable context and will not be able
to reschedule.Vcpu will be halted if guest will fault on the same page again or if
vcpu executes kernel code.Acked-by: Rik van Riel
Signed-off-by: Gleb Natapov
Signed-off-by: Marcelo Tosatti -
If a guest accesses swapped out memory do not swap it in from vcpu thread
context. Schedule work to do swapping and put vcpu into halted state
instead.Interrupts will still be delivered to the guest and if interrupt will
cause reschedule guest will continue to run another task.[avi: remove call to get_user_pages_noio(), nacked by Linus; this
makes everything synchrnous again]Acked-by: Rik van Riel
Signed-off-by: Gleb Natapov
Signed-off-by: Marcelo Tosatti
08 Jan, 2011
2 commits
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The check for NULL skb in the kfree_skb trace event is a duplicate from the
check already done in its only caller, kfree_skb(). Remove this duplicate check.Signed-off-by: Mathieu Desnoyers
LKML-Reference:
Acked-by: Neil Horman
Acked-by: David S. Miller
CC: Steven Rostedt
CC: Frederic Weisbecker
CC: Ingo Molnar
CC: Thomas Gleixner
CC: Zhaolei
Signed-off-by: Steven Rostedt -
While doing some developing, Peter Zijlstra and I have found
that if a CREATE_TRACE_POINTS include is done before module.h
is included, it can break the build.We have been lucky so far that this has not broke the build
since module.h is included in almost everything.Reported-by: Peter Zijlstra
Signed-off-by: Steven Rostedt
07 Jan, 2011
1 commit
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The "error" field in block_bio_complete is not assigned, leaving the memory area
uninitialized (keeping garbage data). Pass an additional tracepoint argument to
this event to initialize this field.Signed-off-by: Jeff Moyer
Signed-off-by: Mathieu Desnoyers
CC: Steven Rostedt
CC: Frederic Weisbecker
CC: Ingo Molnar
CC: Thomas Gleixner
CC: Li Zefan
CC: Alan.Brunelle@hp.com
Signed-off-by: Jens Axboe
04 Jan, 2011
1 commit
-
Add these new power trace events:
power:cpu_idle
power:cpu_frequency
power:machine_suspendThe old C-state/idle accounting events:
power:power_start
power:power_endHave now a replacement (but we are still keeping the old
tracepoints for compatibility):power:cpu_idle
and
power:power_frequencyis replaced with:
power:cpu_frequencypower:machine_suspend is newly introduced.
Jean Pihet has a patch integrated into the generic layer
(kernel/power/suspend.c) which will make use of it.the type= field got removed from both, it was never
used and the type is differed by the event type itself.perf timechart userspace tool gets adjusted in a separate patch.
Signed-off-by: Thomas Renninger
Signed-off-by: Ingo Molnar
Acked-by: Arjan van de Ven
Acked-by: Jean Pihet
Cc: Arnaldo Carvalho de Melo
Cc: Peter Zijlstra
Cc: Linus Torvalds
Cc: rjw@sisk.pl
LKML-Reference:
Signed-off-by: Ingo Molnar
LKML-Reference:
06 Dec, 2010
1 commit
-
As jack detection can trigger DAPM and the latency in debouncing can create
confusing windows in operation provide some trace events which will hopefully
help in diagnostics. The soc-jack core traces all reports that it gets and
the resulting notifications to upper layers. An event for jack IRQs is also
provided for instrumentation of debounce, and used in the GPIO jack code.Signed-off-by: Mark Brown
Acked-by: Liam Girdwood
03 Dec, 2010
1 commit
-
There are instances in the kernel that we only want to trace
a tracepoint when a certain condition is set. But we do not
want to test for that condition in the core kernel.
If we test for that condition before calling the tracepoin, then
we will be performing that test even when tracing is not enabled.
This is 99.99% of the time.We currently can just filter out on that condition, but that happens
after we write to the trace buffer. We just wasted time writing to
the ring buffer for an event we never cared about.This patch adds:
TRACE_EVENT_CONDITION() and DEFINE_EVENT_CONDITION()
These have a new TP_CONDITION() argument that comes right after
the TP_ARGS(). This condition can use the parameters of TP_ARGS()
in the TRACE_EVENT() to determine if the tracepoint should be traced
or not. The TP_CONDITION() will be placed in a if (cond) trace;For example, for the tracepoint sched_wakeup, it is useless to
trace a wakeup event where the caller never actually wakes
anything up (where success == 0). So adding:TP_CONDITION(success),
which uses the "success" parameter of the wakeup tracepoint
will have it only trace when we have successfully woken up a
task.Acked-by: Mathieu Desnoyers
Acked-by: Frederic Weisbecker
Cc: Arjan van de Ven
Cc: Thomas Gleixner
Signed-off-by: Steven Rostedt
19 Nov, 2010
3 commits
-
Currently we have in something like the sched_switch event:
field:char prev_comm[TASK_COMM_LEN]; offset:12; size:16; signed:1;
When a userspace tool such as perf tries to parse this, the
TASK_COMM_LEN is meaningless. This is done because the TRACE_EVENT() macro
simply uses a #len to show the string of the length. When the length is
an enum, we get a string that means nothing for tools.By adding a static buffer and a mutex to protect it, we can store the
string into that buffer with snprintf and show the actual number.
Now we get:field:char prev_comm[16]; offset:12; size:16; signed:1;
Something much more useful.
Signed-off-by: Steven Rostedt
-
…t/kgene/linux-samsung into for-2.6.38
-
…ic/random-tracing into perf/core
18 Nov, 2010
3 commits
-
As for the raw syscalls events, individual syscall events won't
leak system wide information on task bound tracing. Allow non
privileged users to use them in such workflow.Signed-off-by: Frederic Weisbecker
Cc: Ingo Molnar
Cc: Peter Zijlstra
Cc: Arnaldo Carvalho de Melo
Cc: Thomas Gleixner
Cc: Steven Rostedt
Cc: Li Zefan
Cc: Jason Baron -
This allows non privileged users to use the raw syscall trace events
for task bound tracing in perf.It is safe because raw syscall trace events don't leak system wide
informations.Signed-off-by: Frederic Weisbecker
Cc: Ingo Molnar
Cc: Peter Zijlstra
Cc: Arnaldo Carvalho de Melo
Cc: Thomas Gleixner
Cc: Steven Rostedt
Cc: Li Zefan
Cc: Jason Baron -
This introduces the new TRACE_EVENT_FLAGS() macro in order
to set up initial event flags value.This macro must simply follow the definition of a trace event
and take the event name and the flag value as parameters:TRACE_EVENT(my_event, .....
....
);TRACE_EVENT_FLAGS(my_event, 1)
This will set up 1 as the initial my_event->flags value.
Signed-off-by: Frederic Weisbecker
Cc: Ingo Molnar
Cc: Peter Zijlstra
Cc: Arnaldo Carvalho de Melo
Cc: Thomas Gleixner
Cc: Steven Rostedt
Cc: Li Zefan
Cc: Jason Baron
16 Nov, 2010
1 commit
-
Signed-off-by: Kiyoshi Ueda
Signed-off-by: Jun'ichi Nomura
Signed-off-by: Mike Snitzer
Signed-off-by: Jens Axboe
11 Nov, 2010
2 commits
-
Trace events for DAPM allow us to monitor the performance and behaviour
of DAPM with logging which can be built into the kernel permanantly, is
more suited to automated analysis and display and less likely to suffer
interference from other logging activity.Currently trace events are generated for:
- Start and stop of DAPM processing
- Start and stop of bias level changes
- Power decisions for widgets
- Widget event execution start and stopgiving some view as to what is happening and where latencies occur.
Actual changes in widget power can be seen via the register write trace in
soc-core.Signed-off-by: Mark Brown
Acked-by: Liam Girdwood -
The trace subsystem provides a convenient way of instrumenting the kernel
which can be left on all the time with extremely low impact on the system
unlike prints to the kernel log which can be very spammy. Begin adding
support for instrumenting ASoC via this interface by adding trace for the
register access primitives.Signed-off-by: Mark Brown
Acked-by: Liam Girdwood
09 Nov, 2010
1 commit
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Add ext4_evict_inode, ext4_drop_inode, ext4_mark_inode_dirty, and
ext4_begin_ordered_truncate()Signed-off-by: "Theodore Ts'o"
28 Oct, 2010
6 commits
-
Conflicts:
fs/ext4/inode.c
fs/ext4/mballoc.c
include/trace/events/ext4.h -
Unfortunately perf can't deal with anything other than direct structure
accesses in the TP_printk() section. It will drop dead when it sees
jbd2_dev_to_name() in the "print fmt" section of the tracepoint.Addresses-Google-Bug: 3138508
Signed-off-by: "Theodore Ts'o"
-
…/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (50 commits)
perf python scripting: Add futex-contention script
perf python scripting: Fixup cut'n'paste error in sctop script
perf scripting: Shut up 'perf record' final status
perf record: Remove newline character from perror() argument
perf python scripting: Support fedora 11 (audit 1.7.17)
perf python scripting: Improve the syscalls-by-pid script
perf python scripting: print the syscall name on sctop
perf python scripting: Improve the syscalls-counts script
perf python scripting: Improve the failed-syscalls-by-pid script
kprobes: Remove redundant text_mutex lock in optimize
x86/oprofile: Fix uninitialized variable use in debug printk
tracing: Fix 'faild' -> 'failed' typo
perf probe: Fix format specified for Dwarf_Off parameter
perf trace: Fix detection of script extension
perf trace: Use $PERF_EXEC_PATH in canned report scripts
perf tools: Document event modifiers
perf tools: Remove direct slang.h include
perf_events: Fix for transaction recovery in group_sched_in()
perf_events: Revert: Fix transaction recovery in group_sched_in()
perf, x86: Use NUMA aware allocations for PEBS/BTS/DS allocations
... -
Many tracepoints were populating an ext4_allocation_context
to pass in, but this requires a slab allocation even when
tracepoints are off. In fact, 4 of 5 of these allocations
were only for tracing. In addition, we were only using a
small fraction of the 144 bytes of this structure for this
purpose.We can do away with all these alloc/frees of the ac and
simply pass in the bits we care about, instead.I tested this by turning on tracing and running through
xfstests on x86_64. I did not actually do anything with
the trace output, however.Signed-off-by: Eric Sandeen
Signed-off-by: "Theodore Ts'o" -
Our QA reported an oops in the ext4_mb_release_group_pa tracing,
and Josef Bacik pointed out that it was because we may have a
non-null but uninitialized ac_inode in the allocation context.I can reproduce it when running xfstests with ext4 tracepoints on,
on a CONFIG_SLAB_DEBUG kernel.We call trace_ext4_mb_release_group_pa from 2 places,
ext4_mb_discard_group_preallocations and
ext4_mb_discard_lg_preallocationsIn both cases we allocate an ac as a container just for tracing (!)
and never fill in the ac_inode. There's no reason to be assigning,
testing, or printing it as far as I can see, so just remove it from
the tracepoint.Signed-off-by: Eric Sandeen
Reviewed-by: Josef Bacik
Signed-off-by: "Theodore Ts'o" -
ac->inode is set to null in function ext4_mb_release_group_pa(),
and then trace_ext4_mballoc_discard(ac) is called, the kernel
will panic.BUG: unable to handle kernel NULL pointer dereference at 000000a4
IP: [] ftrace_raw_event_ext4__mballoc+0x54/0xc0 [ext4]
*pdpt = 0000000000abd001 *pde = 0000000000000000
Oops: 0000 [#1] SMPPid: 550, comm: flush-8:16 Not tainted 2.6.36-rc1 #1 SE7320EP2/Altos G530
EIP: 0060:[] EFLAGS: 00010206 CPU: 1
EIP is at ftrace_raw_event_ext4__mballoc+0x54/0xc0 [ext4]
EAX: f32ac840 EBX: f3f1cf88 ECX: f32ac840 EDX: 00000000
ESI: f32ac83c EDI: f880b9d8 EBP: 00000000 ESP: f4b77ae4
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process flush-8:16 (pid: 550, ti=f4b76000 task=f613e540 task.ti=f4b76000)
Call Trace:
[] ? ext4_mb_release_group_pa+0x121/0x150 [ext4]
[] ? ext4_mb_discard_group_preallocations+0x336/0x400 [ext4]
[] ? ext4_mb_new_blocks+0x3d1/0x4f0 [ext4]
[] ? __make_request+0x10b/0x440
[] ? ext4_ext_map_blocks+0x1334/0x1980 [ext4]
[] ? rb_reserve_next_event+0xaa/0x3b0
[] ? ext4_map_blocks+0xd6/0x1d0 [ext4]
[] ? mpage_da_map_blocks+0xc7/0x8a0 [ext4]
[] ? find_get_pages_tag+0x38/0x110
[] ? __pagevec_release+0x15/0x20
[] ? ext4_da_writepages+0x2b5/0x5d0 [ext4]
[] ? __writepage+0x0/0x30
[] ? do_writepages+0x14/0x30
[] ? writeback_single_inode+0xa0/0x240
[] ? writeback_sb_inodes+0xc1/0x180
[] ? writeback_inodes_wb+0x88/0x140
[] ? wb_writeback+0x20b/0x320
[] ? lock_timer_base+0x27/0x50
[] ? wb_do_writeback+0x150/0x190
[] ? bdi_writeback_thread+0x88/0x1f0
[] ? complete+0x40/0x60
[] ? bdi_writeback_thread+0x0/0x1f0
[] ? kthread+0x74/0x80
[] ? kthread+0x0/0x80
[] ? kernel_thread_helper+0x6/0x10Signed-off-by: Wen Congyang
Acked-by: Steven Rostedt
Signed-off-by: "Theodore Ts'o"
27 Oct, 2010
1 commit
-
…r if significant congestion is not being encountered in the current zone
If congestion_wait() is called with no BDI congested, the caller will
sleep for the full timeout and this may be an unnecessary sleep. This
patch adds a wait_iff_congested() that checks congestion and only sleeps
if a BDI is congested else, it calls cond_resched() to ensure the caller
is not hogging the CPU longer than its quota but otherwise will not sleep.This is aimed at reducing some of the major desktop stalls reported during
IO. For example, while kswapd is operating, it calls congestion_wait()
but it could just have been reclaiming clean page cache pages with no
congestion. Without this patch, it would sleep for a full timeout but
after this patch, it'll just call schedule() if it has been on the CPU too
long. Similar logic applies to direct reclaimers that are not making
enough progress.Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>