It's a pretty close match to what we had before - the timer triggering
would mean that nobody unplugged the plug in due time, in the new
scheme this matches very closely what the schedule() unplug now is.
It's essentially the difference between an explicit unplug (IO unplug)
or an implicit unplug (timer unplug, we scheduled with pending IO
queued).
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
It was removed with the on-stack plugging, readd it and track the
depth of requests added when flushing the plug.
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Tracepoints can provide insight into why btrfs hits bugs and be greatly
helpful for debugging, e.g
dd-7822 [000] 2121.641088: btrfs_inode_request: root = 5(FS_TREE), gen = 4, ino = 256, blocks = 8, disk_i_size = 0, last_trans = 8, logged_trans = 0
dd-7822 [000] 2121.641100: btrfs_inode_new: root = 5(FS_TREE), gen = 8, ino = 257, blocks = 0, disk_i_size = 0, last_trans = 0, logged_trans = 0
btrfs-transacti-7804 [001] 2146.935420: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29368320 (orig_level = 0), cow_buf = 29388800 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.935473: btrfs_cow_block: root = 1(ROOT_TREE), refs = 2, orig_buf = 29364224 (orig_level = 0), cow_buf = 29392896 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.972221: btrfs_transaction_commit: root = 1(ROOT_TREE), gen = 8
flush-btrfs-2-7821 [001] 2155.824210: btrfs_chunk_alloc: root = 3(CHUNK_TREE), offset = 1103101952, size = 1073741824, num_stripes = 1, sub_stripes = 0, type = DATA
flush-btrfs-2-7821 [001] 2155.824241: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29388800 (orig_level = 0), cow_buf = 29396992 (cow_level = 0)
flush-btrfs-2-7821 [001] 2155.824255: btrfs_cow_block: root = 4(DEV_TREE), refs = 2, orig_buf = 29372416 (orig_level = 0), cow_buf = 29401088 (cow_level = 0)
flush-btrfs-2-7821 [000] 2155.824329: btrfs_cow_block: root = 3(CHUNK_TREE), refs = 2, orig_buf = 20971520 (orig_level = 0), cow_buf = 20975616 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898019: btrfs_cow_block: root = 5(FS_TREE), refs = 2, orig_buf = 29384704 (orig_level = 0), cow_buf = 29405184 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898043: btrfs_cow_block: root = 7(CSUM_TREE), refs = 2, orig_buf = 29376512 (orig_level = 0), cow_buf = 29409280 (cow_level = 0)
Here is what I have added:
1) ordere_extent:
btrfs_ordered_extent_add
btrfs_ordered_extent_remove
btrfs_ordered_extent_start
btrfs_ordered_extent_put
These provide critical information to understand how ordered_extents are
updated.
2) extent_map:
btrfs_get_extent
extent_map is used in both read and write cases, and it is useful for tracking
how btrfs specific IO is running.
3) writepage:
__extent_writepage
btrfs_writepage_end_io_hook
Pages are cirtical resourses and produce a lot of corner cases during writeback,
so it is valuable to know how page is written to disk.
4) inode:
btrfs_inode_new
btrfs_inode_request
btrfs_inode_evict
These can show where and when a inode is created, when a inode is evicted.
5) sync:
btrfs_sync_file
btrfs_sync_fs
These show sync arguments.
6) transaction:
btrfs_transaction_commit
In transaction based filesystem, it will be useful to know the generation and
who does commit.
7) back reference and cow:
btrfs_delayed_tree_ref
btrfs_delayed_data_ref
btrfs_delayed_ref_head
btrfs_cow_block
Btrfs natively supports back references, these tracepoints are helpful on
understanding btrfs's COW mechanism.
8) chunk:
btrfs_chunk_alloc
btrfs_chunk_free
Chunk is a link between physical offset and logical offset, and stands for space
infomation in btrfs, and these are helpful on tracing space things.
9) reserved_extent:
btrfs_reserved_extent_alloc
btrfs_reserved_extent_free
These can show how btrfs uses its space.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
- Add more ext4 tracepoints.
- Change ext4 tracepoints to use dev_t field with MAJOR/MINOR macros
so that we can save 4 bytes in the ring buffer on some platforms.
- Add sync_mode to ext4_da_writepages, ext4_da_write_pages, and
ext4_da_writepages_result tracepoints. Also remove for_reclaim
field from ext4_da_writepages since it is usually not very useful.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When debugging DIF/DIX it is very helpful to be able to see which DIX
operation is associated with the scsi_cmnd. Include the protection op in
the SCSI command trace.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David Sharp <dhsharp@google.com>
LKML-Reference: <1291421609-14665-10-git-send-email-dhsharp@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: David Sharp <dhsharp@google.com>
LKML-Reference: <1291421609-14665-9-git-send-email-dhsharp@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: David Sharp <dhsharp@google.com>
LKML-Reference: <1291421609-14665-7-git-send-email-dhsharp@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
If we enable trace events to trace block actions, We use
blk_fill_rwbs_rq to analyze the corresponding actions
in request's cmd_flags, but we only choose the minor 2 bits
from it, so most of other flags(e.g, REQ_SYNC) are missing.
For example, with a sync write we get:
write_test-2409 [001] 160.013869: block_rq_insert: 3,64 W 0 () 258135 + =
8 [write_test]
Since now we have integrated the flags of both bio and request,
it is safe to pass rq->cmd_flags directly to blk_fill_rwbs and
blk_fill_rwbs_rq isn't needed any more.
With this patch, after a sync write we get:
write_test-2417 [000] 226.603878: block_rq_insert: 3,64 WS 0 () 258135 +=
8 [write_test]
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
This patch makes it easy to see when the syncing process begins and
ends. You can also enable the snd_soc_reg_write tracepoint to see
which registers are being synced.
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
The commit:
9f987b3141f086de27832514aad9f50a53f754
tracing: Include module.h in define_trace.h
only 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/<event>.h file is
included, which (luckily) has not happened yet.
Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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 <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <mel@csn.ul.ie>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <hch@infradead.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Engelhardt <jengelh@medozas.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
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_pf
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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 <riel@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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 <riel@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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 <mathieu.desnoyers@efficios.com>
LKML-Reference: <20110106175319.GA30610@Krystal>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: David S. Miller <davem@davemloft.net>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Zhaolei <zhaolei@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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 <jmoyer@redhat.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Li Zefan <lizf@cn.fujitsu.com>
CC: Alan.Brunelle@hp.com
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Add these new power trace events:
power:cpu_idle
power:cpu_frequency
power:machine_suspend
The old C-state/idle accounting events:
power:power_start
power:power_end
Have now a replacement (but we are still keeping the old
tracepoints for compatibility):
power:cpu_idle
and
power:power_frequency
is replaced with:
power:cpu_frequency
power: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 <trenn@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Jean Pihet <jean.pihet@newoldbits.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: rjw@sisk.pl
LKML-Reference: <1294073445-14812-3-git-send-email-trenn@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <1290072314-31155-2-git-send-email-trenn@suse.de>
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 <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
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 <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jason Baron <jbaron@redhat.com>
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 stop
giving 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 <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
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 <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
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" <tytso@mit.edu>
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 <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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_preallocations
In 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 <sandeen@redhat.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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>
shrink_page_list() can decide to give up reclaiming a page under a
number of conditions such as
1. trylock_page() failure
2. page is unevictable
3. zone reclaim and page is mapped
4. PageWriteback() is true
5. page is swapbacked and swap is full
6. add_to_swap() failure
7. page is dirty and gfpmask don't have GFP_IO, GFP_FS
8. page is pinned
9. IO queue is congested
10. pageout() start IO, but not finished
With lumpy reclaim, failures result in entering synchronous lumpy reclaim
but this can be unnecessary. In cases (2), (3), (5), (6), (7) and (8),
there is no point retrying. This patch causes lumpy reclaim to abort when
it is known it will fail.
Case (9) is more interesting. current behavior is,
1. start shrink_page_list(async)
2. found queue_congested()
3. skip pageout write
4. still start shrink_page_list(sync)
5. wait on a lot of pages
6. again, found queue_congested()
7. give up pageout write again
So, it's useless time wasting. However, just skipping page reclaim is
also notgood as x86 allocating a huge page needs 512 pages for example.
It can have more dirty pages than queue congestion threshold (~=128).
After this patch, pageout() behaves as follows;
- If order > PAGE_ALLOC_COSTLY_ORDER
Ignore queue congestion always.
- If order <= PAGE_ALLOC_COSTLY_ORDER
skip write page and disable lumpy reclaim.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is strong evidence to indicate a lot of time is being spent in
congestion_wait(), some of it unnecessarily. This patch adds a tracepoint
for congestion_wait to record when congestion_wait() was called, how long
the timeout was for and how long it actually slept.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There have been numerous reports of stalls that pointed at the problem
being somewhere in the VM. There are multiple roots to the problems which
means dealing with any of the root problems in isolation is tricky to
justify on their own and they would still need integration testing. This
patch series puts together two different patch sets which in combination
should tackle some of the root causes of latency problems being reported.
Patch 1 adds a tracepoint for shrink_inactive_list. For this series, the
most important results is being able to calculate the scanning/reclaim
ratio as a measure of the amount of work being done by page reclaim.
Patch 2 accounts for time spent in congestion_wait.
Patches 3-6 were originally developed by Kosaki Motohiro but reworked for
this series. It has been noted that lumpy reclaim is far too aggressive
and trashes the system somewhat. As SLUB uses high-order allocations, a
large cost incurred by lumpy reclaim will be noticeable. It was also
reported during transparent hugepage support testing that lumpy reclaim
was trashing the system and these patches should mitigate that problem
without disabling lumpy reclaim.
Patch 7 adds wait_iff_congested() and replaces some callers of
congestion_wait(). wait_iff_congested() only sleeps if there is a BDI
that is currently congested. Patch 8 notes that any BDI being congested
is not necessarily a problem because there could be multiple BDIs of
varying speeds and numberous zones. It attempts to track when a zone
being reclaimed contains many pages backed by a congested BDI and if so,
reclaimers wait on the congestion queue.
I ran a number of tests with monitoring on X86, X86-64 and PPC64. Each
machine had 3G of RAM and the CPUs were
X86: Intel P4 2-core
X86-64: AMD Phenom 4-core
PPC64: PPC970MP
Each used a single disk and the onboard IO controller. Dirty ratio was
left at 20. I'm just going to report for X86-64 and PPC64 in a vague
attempt to keep this report short. Four kernels were tested each based on
v2.6.36-rc4
traceonly-v2r2: Patches 1 and 2 to instrument vmscan reclaims and congestion_wait
lowlumpy-v2r3: Patches 1-6 to test if lumpy reclaim is better
waitcongest-v2r3: Patches 1-7 to only wait on congestion
waitwriteback-v2r4: Patches 1-8 to detect when a zone is congested
nocongest-v1r5: Patches 1-3 for testing wait_iff_congestion
nodirect-v1r5: Patches 1-10 to disable filesystem writeback for better IO
The tests run were as follows
kernbench
compile-based benchmark. Smoke test performance
sysbench
OLTP read-only benchmark. Will be re-run in the future as read-write
micro-mapped-file-stream
This is a micro-benchmark from Johannes Weiner that accesses a
large sparse-file through mmap(). It was configured to run in only
single-CPU mode but can be indicative of how well page reclaim
identifies suitable pages.
stress-highalloc
Tries to allocate huge pages under heavy load.
kernbench, iozone and sysbench did not report any performance regression
on any machine. sysbench did pressure the system lightly and there was
reclaim activity but there were no difference of major interest between
the kernels.
X86-64 micro-mapped-file-stream
traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3 waitwriteback-v2r4
pgalloc_dma 1639.00 ( 0.00%) 667.00 (-145.73%) 1167.00 ( -40.45%) 578.00 (-183.56%)
pgalloc_dma32 2842410.00 ( 0.00%) 2842626.00 ( 0.01%) 2843043.00 ( 0.02%) 2843014.00 ( 0.02%)
pgalloc_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%)
pgsteal_dma 729.00 ( 0.00%) 85.00 (-757.65%) 609.00 ( -19.70%) 125.00 (-483.20%)
pgsteal_dma32 2338721.00 ( 0.00%) 2447354.00 ( 4.44%) 2429536.00 ( 3.74%) 2436772.00 ( 4.02%)
pgsteal_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%)
pgscan_kswapd_dma 1469.00 ( 0.00%) 532.00 (-176.13%) 1078.00 ( -36.27%) 220.00 (-567.73%)
pgscan_kswapd_dma32 4597713.00 ( 0.00%) 4503597.00 ( -2.09%) 4295673.00 ( -7.03%) 3891686.00 ( -18.14%)
pgscan_kswapd_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%)
pgscan_direct_dma 71.00 ( 0.00%) 134.00 ( 47.01%) 243.00 ( 70.78%) 352.00 ( 79.83%)
pgscan_direct_dma32 305820.00 ( 0.00%) 280204.00 ( -9.14%) 600518.00 ( 49.07%) 957485.00 ( 68.06%)
pgscan_direct_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%)
pageoutrun 16296.00 ( 0.00%) 21254.00 ( 23.33%) 18447.00 ( 11.66%) 20067.00 ( 18.79%)
allocstall 443.00 ( 0.00%) 273.00 ( -62.27%) 513.00 ( 13.65%) 1568.00 ( 71.75%)
These are based on the raw figures taken from /proc/vmstat. It's a rough
measure of reclaim activity. Note that allocstall counts are higher
because we are entering direct reclaim more often as a result of not
sleeping in congestion. In itself, it's not necessarily a bad thing.
It's easier to get a view of what happened from the vmscan tracepoint
report.
FTrace Reclaim Statistics: vmscan
traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3 waitwriteback-v2r4
Direct reclaims 443 273 513 1568
Direct reclaim pages scanned 305968 280402 600825 957933
Direct reclaim pages reclaimed 43503 19005 30327 117191
Direct reclaim write file async I/O 0 0 0 0
Direct reclaim write anon async I/O 0 3 4 12
Direct reclaim write file sync I/O 0 0 0 0
Direct reclaim write anon sync I/O 0 0 0 0
Wake kswapd requests 187649 132338 191695 267701
Kswapd wakeups 3 1 4 1
Kswapd pages scanned 4599269 4454162 4296815 3891906
Kswapd pages reclaimed 2295947 2428434 2399818 2319706
Kswapd reclaim write file async I/O 1 0 1 1
Kswapd reclaim write anon async I/O 59 187 41 222
Kswapd reclaim write file sync I/O 0 0 0 0
Kswapd reclaim write anon sync I/O 0 0 0 0
Time stalled direct reclaim (seconds) 4.34 2.52 6.63 2.96
Time kswapd awake (seconds) 11.15 10.25 11.01 10.19
Total pages scanned 4905237 4734564 4897640 4849839
Total pages reclaimed 2339450 2447439 2430145 2436897
%age total pages scanned/reclaimed 47.69% 51.69% 49.62% 50.25%
%age total pages scanned/written 0.00% 0.00% 0.00% 0.00%
%age file pages scanned/written 0.00% 0.00% 0.00% 0.00%
Percentage Time Spent Direct Reclaim 29.23% 19.02% 38.48% 20.25%
Percentage Time kswapd Awake 78.58% 78.85% 76.83% 79.86%
What is interesting here for nocongest in particular is that while direct
reclaim scans more pages, the overall number of pages scanned remains the
same and the ratio of pages scanned to pages reclaimed is more or less the
same. In other words, while we are sleeping less, reclaim is not doing
more work and as direct reclaim and kswapd is awake for less time, it
would appear to be doing less work.
FTrace Reclaim Statistics: congestion_wait
Direct number congest waited 87 196 64 0
Direct time congest waited 4604ms 4732ms 5420ms 0ms
Direct full congest waited 72 145 53 0
Direct number conditional waited 0 0 324 1315
Direct time conditional waited 0ms 0ms 0ms 0ms
Direct full conditional waited 0 0 0 0
KSwapd number congest waited 20 10 15 7
KSwapd time congest waited 1264ms 536ms 884ms 284ms
KSwapd full congest waited 10 4 6 2
KSwapd number conditional waited 0 0 0 0
KSwapd time conditional waited 0ms 0ms 0ms 0ms
KSwapd full conditional waited 0 0 0 0
The vanilla kernel spent 8 seconds asleep in direct reclaim and no time at
all asleep with the patches.
MMTests Statistics: duration
User/Sys Time Running Test (seconds) 10.51 10.73 10.6 11.66
Total Elapsed Time (seconds) 14.19 13.00 14.33 12.76
Overall, the tests completed faster. It is interesting to note that backing off further
when a zone is congested and not just a BDI was more efficient overall.
PPC64 micro-mapped-file-stream
pgalloc_dma 3024660.00 ( 0.00%) 3027185.00 ( 0.08%) 3025845.00 ( 0.04%) 3026281.00 ( 0.05%)
pgalloc_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%)
pgsteal_dma 2508073.00 ( 0.00%) 2565351.00 ( 2.23%) 2463577.00 ( -1.81%) 2532263.00 ( 0.96%)
pgsteal_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%)
pgscan_kswapd_dma 4601307.00 ( 0.00%) 4128076.00 ( -11.46%) 3912317.00 ( -17.61%) 3377165.00 ( -36.25%)
pgscan_kswapd_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%)
pgscan_direct_dma 629825.00 ( 0.00%) 971622.00 ( 35.18%) 1063938.00 ( 40.80%) 1711935.00 ( 63.21%)
pgscan_direct_normal 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%) 0.00 ( 0.00%)
pageoutrun 27776.00 ( 0.00%) 20458.00 ( -35.77%) 18763.00 ( -48.04%) 18157.00 ( -52.98%)
allocstall 977.00 ( 0.00%) 2751.00 ( 64.49%) 2098.00 ( 53.43%) 5136.00 ( 80.98%)
Similar trends to x86-64. allocstalls are up but it's not necessarily bad.
FTrace Reclaim Statistics: vmscan
Direct reclaims 977 2709 2098 5136
Direct reclaim pages scanned 629825 963814 1063938 1711935
Direct reclaim pages reclaimed 75550 242538 150904 387647
Direct reclaim write file async I/O 0 0 0 2
Direct reclaim write anon async I/O 0 10 0 4
Direct reclaim write file sync I/O 0 0 0 0
Direct reclaim write anon sync I/O 0 0 0 0
Wake kswapd requests 392119 1201712 571935 571921
Kswapd wakeups 3 2 3 3
Kswapd pages scanned 4601307 4128076 3912317 3377165
Kswapd pages reclaimed 2432523 2318797 2312673 2144616
Kswapd reclaim write file async I/O 20 1 1 1
Kswapd reclaim write anon async I/O 57 132 11 121
Kswapd reclaim write file sync I/O 0 0 0 0
Kswapd reclaim write anon sync I/O 0 0 0 0
Time stalled direct reclaim (seconds) 6.19 7.30 13.04 10.88
Time kswapd awake (seconds) 21.73 26.51 25.55 23.90
Total pages scanned 5231132 5091890 4976255 5089100
Total pages reclaimed 2508073 2561335 2463577 2532263
%age total pages scanned/reclaimed 47.95% 50.30% 49.51% 49.76%
%age total pages scanned/written 0.00% 0.00% 0.00% 0.00%
%age file pages scanned/written 0.00% 0.00% 0.00% 0.00%
Percentage Time Spent Direct Reclaim 18.89% 20.65% 32.65% 27.65%
Percentage Time kswapd Awake 72.39% 80.68% 78.21% 77.40%
Again, a similar trend that the congestion_wait changes mean that direct
reclaim scans more pages but the overall number of pages scanned while
slightly reduced, are very similar. The ratio of scanning/reclaimed
remains roughly similar. The downside is that kswapd and direct reclaim
was awake longer and for a larger percentage of the overall workload.
It's possible there were big differences in the amount of time spent
reclaiming slab pages between the different kernels which is plausible
considering that the micro tests runs after fsmark and sysbench.
Trace Reclaim Statistics: congestion_wait
Direct number congest waited 845 1312 104 0
Direct time congest waited 19416ms 26560ms 7544ms 0ms
Direct full congest waited 745 1105 72 0
Direct number conditional waited 0 0 1322 2935
Direct time conditional waited 0ms 0ms 12ms 312ms
Direct full conditional waited 0 0 0 3
KSwapd number congest waited 39 102 75 63
KSwapd time congest waited 2484ms 6760ms 5756ms 3716ms
KSwapd full congest waited 20 48 46 25
KSwapd number conditional waited 0 0 0 0
KSwapd time conditional waited 0ms 0ms 0ms 0ms
KSwapd full conditional waited 0 0 0 0
The vanilla kernel spent 20 seconds asleep in direct reclaim and only
312ms asleep with the patches. The time kswapd spent congest waited was
also reduced by a large factor.
MMTests Statistics: duration
ser/Sys Time Running Test (seconds) 26.58 28.05 26.9 28.47
Total Elapsed Time (seconds) 30.02 32.86 32.67 30.88
With all patches applies, the completion times are very similar.
X86-64 STRESS-HIGHALLOC
traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4
Pass 1 82.00 ( 0.00%) 84.00 ( 2.00%) 85.00 ( 3.00%) 85.00 ( 3.00%)
Pass 2 90.00 ( 0.00%) 87.00 (-3.00%) 88.00 (-2.00%) 89.00 (-1.00%)
At Rest 92.00 ( 0.00%) 90.00 (-2.00%) 90.00 (-2.00%) 91.00 (-1.00%)
Success figures across the board are broadly similar.
traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4
Direct reclaims 1045 944 886 887
Direct reclaim pages scanned 135091 119604 109382 101019
Direct reclaim pages reclaimed 88599 47535 47863 46671
Direct reclaim write file async I/O 494 283 465 280
Direct reclaim write anon async I/O 29357 13710 16656 13462
Direct reclaim write file sync I/O 154 2 2 3
Direct reclaim write anon sync I/O 14594 571 509 561
Wake kswapd requests 7491 933 872 892
Kswapd wakeups 814 778 731 780
Kswapd pages scanned 7290822 15341158 11916436 13703442
Kswapd pages reclaimed 3587336 3142496 3094392 3187151
Kswapd reclaim write file async I/O 91975 32317 28022 29628
Kswapd reclaim write anon async I/O 1992022 789307 829745 849769
Kswapd reclaim write file sync I/O 0 0 0 0
Kswapd reclaim write anon sync I/O 0 0 0 0
Time stalled direct reclaim (seconds) 4588.93 2467.16 2495.41 2547.07
Time kswapd awake (seconds) 2497.66 1020.16 1098.06 1176.82
Total pages scanned 7425913 15460762 12025818 13804461
Total pages reclaimed 3675935 3190031 3142255 3233822
%age total pages scanned/reclaimed 49.50% 20.63% 26.13% 23.43%
%age total pages scanned/written 28.66% 5.41% 7.28% 6.47%
%age file pages scanned/written 1.25% 0.21% 0.24% 0.22%
Percentage Time Spent Direct Reclaim 57.33% 42.15% 42.41% 42.99%
Percentage Time kswapd Awake 43.56% 27.87% 29.76% 31.25%
Scanned/reclaimed ratios again look good with big improvements in
efficiency. The Scanned/written ratios also look much improved. With a
better scanned/written ration, there is an expectation that IO would be
more efficient and indeed, the time spent in direct reclaim is much
reduced by the full series and kswapd spends a little less time awake.
Overall, indications here are that allocations were happening much faster
and this can be seen with a graph of the latency figures as the
allocations were taking place
http://www.csn.ul.ie/~mel/postings/vmscanreduce-20101509/highalloc-interlatency-hydra-mean.ps
FTrace Reclaim Statistics: congestion_wait
Direct number congest waited 1333 204 169 4
Direct time congest waited 78896ms 8288ms 7260ms 200ms
Direct full congest waited 756 92 69 2
Direct number conditional waited 0 0 26 186
Direct time conditional waited 0ms 0ms 0ms 2504ms
Direct full conditional waited 0 0 0 25
KSwapd number congest waited 4 395 227 282
KSwapd time congest waited 384ms 25136ms 10508ms 18380ms
KSwapd full congest waited 3 232 98 176
KSwapd number conditional waited 0 0 0 0
KSwapd time conditional waited 0ms 0ms 0ms 0ms
KSwapd full conditional waited 0 0 0 0
KSwapd full conditional waited 318 0 312 9
Overall, the time spent speeping is reduced. kswapd is still hitting
congestion_wait() but that is because there are callers remaining where it
wasn't clear in advance if they should be changed to wait_iff_congested()
or not. Overall the sleep imes are reduced though - from 79ish seconds to
about 19.
MMTests Statistics: duration
User/Sys Time Running Test (seconds) 3415.43 3386.65 3388.39 3377.5
Total Elapsed Time (seconds) 5733.48 3660.33 3689.41 3765.39
With the full series, the time to complete the tests are reduced by 30%
PPC64 STRESS-HIGHALLOC
traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4
Pass 1 17.00 ( 0.00%) 34.00 (17.00%) 38.00 (21.00%) 43.00 (26.00%)
Pass 2 25.00 ( 0.00%) 37.00 (12.00%) 42.00 (17.00%) 46.00 (21.00%)
At Rest 49.00 ( 0.00%) 43.00 (-6.00%) 45.00 (-4.00%) 51.00 ( 2.00%)
Success rates there are *way* up particularly considering that the 16MB
huge pages on PPC64 mean that it's always much harder to allocate them.
FTrace Reclaim Statistics: vmscan
stress-highalloc stress-highalloc stress-highalloc stress-highalloc
traceonly-v2r2 lowlumpy-v2r3 waitcongest-v2r3waitwriteback-v2r4
Direct reclaims 499 505 564 509
Direct reclaim pages scanned 223478 41898 51818 45605
Direct reclaim pages reclaimed 137730 21148 27161 23455
Direct reclaim write file async I/O 399 136 162 136
Direct reclaim write anon async I/O 46977 2865 4686 3998
Direct reclaim write file sync I/O 29 0 1 3
Direct reclaim write anon sync I/O 31023 159 237 239
Wake kswapd requests 420 351 360 326
Kswapd wakeups 185 294 249 277
Kswapd pages scanned 15703488 16392500 17821724 17598737
Kswapd pages reclaimed 5808466 2908858 3139386 3145435
Kswapd reclaim write file async I/O 159938 18400 18717 13473
Kswapd reclaim write anon async I/O 3467554 228957 322799 234278
Kswapd reclaim write file sync I/O 0 0 0 0
Kswapd reclaim write anon sync I/O 0 0 0 0
Time stalled direct reclaim (seconds) 9665.35 1707.81 2374.32 1871.23
Time kswapd awake (seconds) 9401.21 1367.86 1951.75 1328.88
Total pages scanned 15926966 16434398 17873542 17644342
Total pages reclaimed 5946196 2930006 3166547 3168890
%age total pages scanned/reclaimed 37.33% 17.83% 17.72% 17.96%
%age total pages scanned/written 23.27% 1.52% 1.94% 1.43%
%age file pages scanned/written 1.01% 0.11% 0.11% 0.08%
Percentage Time Spent Direct Reclaim 44.55% 35.10% 41.42% 36.91%
Percentage Time kswapd Awake 86.71% 43.58% 52.67% 41.14%
While the scanning rates are slightly up, the scanned/reclaimed and
scanned/written figures are much improved. The time spent in direct
reclaim and with kswapd are massively reduced, mostly by the lowlumpy
patches.
FTrace Reclaim Statistics: congestion_wait
Direct number congest waited 725 303 126 3
Direct time congest waited 45524ms 9180ms 5936ms 300ms
Direct full congest waited 487 190 52 3
Direct number conditional waited 0 0 200 301
Direct time conditional waited 0ms 0ms 0ms 1904ms
Direct full conditional waited 0 0 0 19
KSwapd number congest waited 0 2 23 4
KSwapd time congest waited 0ms 200ms 420ms 404ms
KSwapd full congest waited 0 2 2 4
KSwapd number conditional waited 0 0 0 0
KSwapd time conditional waited 0ms 0ms 0ms 0ms
KSwapd full conditional waited 0 0 0 0
Not as dramatic a story here but the time spent asleep is reduced and we
can still see what wait_iff_congested is going to sleep when necessary.
MMTests Statistics: duration
User/Sys Time Running Test (seconds) 12028.09 3157.17 3357.79 3199.16
Total Elapsed Time (seconds) 10842.07 3138.72 3705.54 3229.85
The time to complete this test goes way down. With the full series, we
are allocating over twice the number of huge pages in 30% of the time and
there is a corresponding impact on the allocation latency graph available
at.
http://www.csn.ul.ie/~mel/postings/vmscanreduce-20101509/highalloc-interlatency-powyah-mean.ps
This patch:
Add a trace event for shrink_inactive_list() and updates the sample
postprocessing script appropriately. It can be used to determine how many
pages were reclaimed and for non-lumpy reclaim where exactly the pages
were reclaimed from.
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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes more dead code that was somehow missed by commit 0d99519efe
(writeback: remove unused nonblocking and congestion checks). There are
no behavior change except for the removal of two entries from one of the
ext4 tracing interface.
The nonblocking checks in ->writepages are no longer used because the
flusher now prefer to block on get_request_wait() than to skip inodes on
IO congestion. The latter will lead to more seeky IO.
The nonblocking checks in ->writepage are no longer used because it's
redundant with the WB_SYNC_NONE check.
We no long set ->nonblocking in VM page out and page migration, because
a) it's effectively redundant with WB_SYNC_NONE in current code
b) it's old semantic of "Don't get stuck on request queues" is mis-behavior:
that would skip some dirty inodes on congestion and page out others, which
is unfair in terms of LRU age.
Inspired by Christoph Hellwig. Thanks!
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Sage Weil <sage@newdream.net>
Cc: Steve French <sfrench@samba.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the addition of trace_softirq_raise() the softirq tracepoint got
even more convoluted. Why the tracepoints take two pointers to assign
an integer is beyond my comprehension.
But adding an extra case which treats the first pointer as an unsigned
long when the second pointer is NULL including the back and forth
type casting is just horrible.
Convert the softirq tracepoints to take a single unsigned int argument
for the softirq vector number and fix the call sites.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <alpine.LFD.2.00.1010191428560.6815@localhost6.localdomain6>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: mathieu.desnoyers@efficios.com
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
These two tracepoints allow tracking when and how a work is queued and
activated. This patch is based on Frederic's patch to add queue_work
trace point.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Define workqueue_work event class and use it for workqueue_execute_end
trace point. Also, move trace/events/workqueue.h include downwards
such that all struct definitions are visible to it. This is to
prepare for more tracepoints and doesn't cause any functional change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Add a tracepoint that shows the priority of a task being boosted
via priority inheritance.
Cc: Gregory Haskins <ghaskins@novell.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This patch adds new generic events for dynamic power management
tracing:
- clock events class: used for clock enable/disable and for
clock rate change,
- power_domain events class: used for power domains transitions.
The OMAP architecture will be using the new events for PM debugging,
however the new events are made generic enough to be used by all
platforms.
Signed-off-by: Jean Pihet <j-pihet@ti.com>
Acked-by: Thomas Renninger <trenn@suse.de>
Cc: discuss@lesswatts.org
Cc: linux-pm@lists.linux-foundation.org
Cc: Thomas Renninger <trenn@suse.de>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
LKML-Reference: <AANLkTinUmbSUUuxUzc8++pcb9gd1CZFdyTQFrveTBXyV@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds tracepoint to consume_skb and add trace_kfree_skb
before __kfree_skb in skb_free_datagram_locked and net_tx_action.
Combinating with tracepoint on dev_hard_start_xmit, we can check
how long it takes to free transmitted packets. And using it, we can
calculate how many packets driver had at that time. It is useful when
a drop of transmitted packet is a problem.
sshd-6828 [000] 112689.258154: consume_skb: skbaddr=f2d99bb8
Signed-off-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Kaneshige Kenji <kaneshige.kenji@jp.fujitsu.com>
Cc: Izumo Taku <izumi.taku@jp.fujitsu.com>
Cc: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Scott Mcmillan <scott.a.mcmillan@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <4C724364.50903@jp.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
This patch converts trace_napi_poll from DECLARE_EVENT to TRACE_EVENT
to improve the usability of napi_poll tracepoint.
<idle>-0 [001] 241302.750777: napi_poll: napi poll on napi struct f6acc480 for device eth3
<idle>-0 [000] 241302.852389: napi_poll: napi poll on napi struct f5d0d70c for device eth1
The original patch is below:
http://marc.info/?l=linux-kernel&m=126021713809450&w=2
[ sanagi.koki@jp.fujitsu.com: And add a fix by Steven Rostedt:
http://marc.info/?l=linux-kernel&m=126150506519173&w=2 ]
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Kaneshige Kenji <kaneshige.kenji@jp.fujitsu.com>
Cc: Izumo Taku <izumi.taku@jp.fujitsu.com>
Cc: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Scott Mcmillan <scott.a.mcmillan@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <4C7242D7.4050009@jp.fujitsu.com>
Signed-off-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Add a tracepoint for tracing when softirq action is raised.
This and the existing tracepoints complete softirq's tracepoints:
softirq_raise, softirq_entry and softirq_exit.
And when this tracepoint is used in combination with
the softirq_entry tracepoint we can determine
the softirq raise latency.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: David Miller <davem@davemloft.net>
Cc: Kaneshige Kenji <kaneshige.kenji@jp.fujitsu.com>
Cc: Izumo Taku <izumi.taku@jp.fujitsu.com>
Cc: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Scott Mcmillan <scott.a.mcmillan@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <4C724298.4050509@jp.fujitsu.com>
[ factorize softirq events with DECLARE_EVENT_CLASS ]
Signed-off-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Jens Axboe