lock_acquired, lock_contended and lock_release now share the
same prototype and format. Let's factorize them into a lock
event class.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Steven Rostedt <rostedt@goodmis.org>

Drop the nested field as we don't use it. Every nested state can
be computed from a state machine on post processing already.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Steven Rostedt <rostedt@goodmis.org>

Drop the waittime field from the lock_acquired event, we can
calculate it by substracting the lock_acquired event timestamp
with the matching lock_acquire one.

It is not needed and takes useless space in the traces.
Signed-off-by: NFrederic 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: Paul Mackerras <paulus@samba.org>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Steven Rostedt <rostedt@goodmis.org>

This patch adds a simple description of the various block tracepoints
available in the kernel.
Signed-off-by: NWilliam Cohen <wcohen@redhat.com>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NAvi Kivity <avi@redhat.com>

Signed-off-by: NAvi Kivity <avi@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Add wait time and lock identification details.
Signed-off-by: NHitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1264851813-8413-11-git-send-email-mitake@dcl.info.waseda.ac.jp>
[ removed the file/line bits as we can do that better via IPs ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Compiling powerpc64 results in:

include/trace/events/timer.h:279: warning:
format '%lu' expects type 'long unsigned int', but argument 4 has type 'cputime_t'
....

cputime_t on power is u64, which triggers the above warning.

Cast the cputime_t to unsigned long long and fix the print format
string. That works on both 32 and 64 bit architectures.

While at it change the print format for long variables from %lu to %ld.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>

Add tracepoints for ext4_da_reserve_space(),
ext4_da_update_reserve_space(), and ext4_da_release_space().
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Add signal_overflow_fail and signal_lose_info tracepoints
for signal-lost events.

Changes in v3:
 - Add docbook style comments

Changes in v2:
 - Use siginfo string macro
Suggested-by: NRoland McGrath <roland@redhat.com>
Reviewed-by: NJason Baron <jbaron@redhat.com>
Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
Acked-by: NRoland McGrath <roland@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Oleg Nesterov <oleg@redhat.com>
LKML-Reference: <20091124215658.30449.9934.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Add a tracepoint where a process gets a signal. This tracepoint
shows signal-number, sa-handler and sa-flag.

Changes in v3:
 - Add docbook style comments

Changes in v2:
 - Add siginfo argument
 - Fix comment
Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
Reviewed-by: NJason Baron <jbaron@redhat.com>
Acked-by: NRoland McGrath <roland@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Oleg Nesterov <oleg@redhat.com>
LKML-Reference: <20091124215651.30449.20926.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Move signal sending event to events/signal.h. This patch also
renames sched_signal_send event to signal_generate.

Changes in v4:
 - Fix a typo of task_struct pointer.

Changes in v3:
 - Add docbook style comments

Changes in v2:
 - Add siginfo argument
 - Add siginfo storing macro
Signed-off-by: NMasami Hiramatsu <mhiramat@redhat.com>
Reviewed-by: NJason Baron <jbaron@redhat.com>
Acked-by: NRoland McGrath <roland@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Oleg Nesterov <oleg@redhat.com>
LKML-Reference: <20091124215645.30449.60208.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The original format for sched_stat_iowait and sched_stat_sleep:

  $ cat events/sched/sched_stat_iowait/format
  ...
  print fmt: "comm=%s pid=%d delay=%Lu [ns]", ...
  $ cat events/sched/sched_stat_sleep/format
  ...
  print fmt: "comm=%s pid=%d delay=%Lu [ns]", ...

But commit commit 75ec29ab
("tracing: Convert some sched trace events to DEFINE_EVENT and
_PRINT") broke the format:

  $ cat events/sched/sched_stat_iowait/format
  print fmt: "task: %s:%d iowait: %Lu [ns]", ...
  $ cat events/sched/sched_stat_sleep/format
  print fmt: "task: %s:%d sleep: %Lu [ns]", ...

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E2951.9050800@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use DECLARE_EVENT_CLASS to remove duplicate code:

   text    data     bss     dec     hex filename
 294695    6104     340  301139   49853 fs/ext4/ext4.o.old
 289983    6104     324  296411   485db fs/ext4/ext4.o

5 events are convertd:

  ext4__write_begin: ext4_write_begin, ext4_da_write_begin
  ext4__write_end: ext4_{ordered, writeback, journalled}_write_end

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E2938.2040708@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use DECLARE_EVENT_CLASS to remove duplicate code:

   text    data     bss     dec     hex filename
  34903    1693     448   37044    90b4 fs/jbd2/journal.o.old
  31931    1693     416   34040    84f8 fs/jbd2/journal.o

Four events are converted:

  jbd2_commit: jbd2_start_commit,
               jbd2_commit_{locking, flushing, logging}

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E290F.7030909@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

use DECLARE_EVENT_CLASS to remove duplicate code:

   text    data     bss     dec     hex filename
  53570    3284     184   57038    dece block/blk-core.o.old
  43702    3284     144   47130    b81a block/blk-core.o

12 events are converted:

  block_rq: block_rq_insert, block_rq_issue
  block_rq_with_error: block_rq_{abort, requeue, complete}
  block_bio: block_bio_{backmerge, frontmerge, queue}
  block_get_rq: block_getrq, block_sleeprq
  block_unplug: block_unplug_timer, block_unplug_io

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E28E6.7060609@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use DECLARE_EVENT_CLASS to remove duplicate code:

   text    data     bss     dec     hex filename
   4312     524      12    4848    12f0 kernel/trace/power-traces.o.old
   3455     524       8    3987     f93 kernel/trace/power-traces.o

Two events are converted:

  power: power_start, power_frequency

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
LKML-Reference: <4B0E28C2.1090906@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use DECLARE_EVENT_CLASS to remove duplicate code:

   text    data     bss     dec     hex filename
  13171     800      72   14043    36db kernel/workqueue.o.old
  12243     800      68   13111    3337 kernel/workqueue.o

Two events are converted:

  workqueue: workqueue_insertion, workqueue_execution

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E289F.5010104@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use DECLARE_EVENT_CLASS to remove duplicate code:

   text    data     bss     dec     hex filename
  12781     952      36   13769    35c9 kernel/softirq.o.old
  11981     952      32   12965    32a5 kernel/softirq.o

Two events are converted:

  softirq: softirq_entry, softirq_exit

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E287F.4030708@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use DECLARE_EVENT_CLASS to remove duplicate code:

   text    data     bss     dec     hex filename
 333987   69800   27228  431015   693a7 mm/built-in.o.old
 330030   69800   27228  427058   68432 mm/built-in.o

8 events are converted:

  kmem_alloc: kmalloc, kmem_cache_alloc
  kmem_alloc_node: kmalloc_node, kmem_cache_alloc_node
  kmem_free: kfree, kmem_cache_free
  mm_page: mm_page_alloc_zone_locked, mm_page_pcpu_drain

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NPekka Enberg <penberg@cs.helsinki.fi>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
LKML-Reference: <4B0E286A.2000405@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Use DECLARE_EVENT_CLASS to remove duplicate code:

   text    data     bss     dec     hex filename
  29854    1980     128   31962    7cda kernel/module.o.old
  28750    1980     128   30858    788a kernel/module.o

Two events are converted:

  module_refcnt: module_get, module_put

No change in functionality.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E283B.3010508@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

It is not quite obvious at first sight what TRACE_EVENT_TEMPLATE
does: does it define an event as well beyond defining a template?

To clarify this, rename it to DECLARE_EVENT_CLASS, which follows
the various 'DECLARE_*()' idioms we already have in the kernel:

  DECLARE_EVENT_CLASS(class)

    DEFINE_EVENT(class, event1)
    DEFINE_EVENT(class, event2)
    DEFINE_EVENT(class, event3)

To complete this logic we should also rename TRACE_EVENT() to:

  DEFINE_SINGLE_EVENT(single_event)

... but in a more quiet moment of the kernel cycle.

Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E286A.2000405@cn.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The current syscall tracer mixes raw syscalls and real syscalls.

echo 1 > events/syscalls/enable
And we get these from the output:

(XXXX insteads "            grep-20914 [001] 588211.446347" .. etc)

XXXX: sys_read(fd: 3, buf: 80609a8, count: 7000)
XXXX: sys_enter: NR 3 (3, 80609a8, 7000, a, 1000, bfce8ef8)
XXXX: sys_read -> 0x138
XXXX: sys_exit: NR 3 = 312
XXXX: sys_read(fd: 3, buf: 8060ae0, count: 7000)
XXXX: sys_enter: NR 3 (3, 8060ae0, 7000, a, 1000, bfce8ef8)
XXXX: sys_read -> 0x138
XXXX: sys_exit: NR 3 = 312

There are 2 drawbacks here.
A) two almost identical records are saved in ringbuffer
   when a syscall enters or exits. (4 records for every syscall)
   This wastes precious space in the ring buffer.
B) the lines including "sys_enter/sys_exit" produces
   hardly any useful information for the output (no labels).

The user can use this method to prevent these drawbacks:
echo 1 > events/syscalls/enable
echo 0 > events/syscalls/sys_enter/enable
echo 0 > events/syscalls/sys_exit/enable

But this is not user friendly. So we separate raw syscall
from syscall tracer.

After this fix applied:
syscall tracer's output (echo 1 > events/syscalls/enable):

XXXX: sys_read(fd: 3, buf: bfe87d88, count: 200)
XXXX: sys_read -> 0x200
XXXX: sys_fstat64(fd: 3, statbuf: bfe87c98)
XXXX: sys_fstat64 -> 0x0
XXXX: sys_close(fd: 3)

raw syscall tracer's output (echo 1 > events/raw_syscalls/enable):

XXXX: sys_enter: NR 175 (0, bf92bf18, bf92bf98, 8, b748cff4, bf92bef8)
XXXX: sys_exit: NR 175 = 0
XXXX: sys_enter: NR 175 (2, bf92bf98, 0, 8, b748cff4, bf92bef8)
XXXX: sys_exit: NR 175 = 0
XXXX: sys_enter: NR 3 (9, bf927f9c, 4000, b77e2518, b77dce60, bf92bff8)
Signed-off-by: NLai Jiangshan <laijs@cn.fujitsu.com>
LKML-Reference: <4AEFC37C.5080609@cn.fujitsu.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Converting some of the scheduler trace events to use the
TRACE_EVENT_TEMPLATE, DEFINE_EVENT and DEFINE_EVENT_PRINT helped to
save some space:

$ size kernel/sched.o-*
   text	   data	    bss	    dec	    hex	filename
  79299	   6776	   2520	  88595	  15a13	kernel/sched.o-notrace
 101941	  11896	   2584	 116421	  1c6c5	kernel/sched.o-templ
 104779	  11896	   2584	 119259	  1d1db	kernel/sched.o-trace

sched.o-notrace is without any tracepoints compiled
sched.o-templ is with this patch
sched.o-trace is the tracepoints before this patch

The trace events converted to DEFINE_EVENT:

sched_wakeup, sched_wakeup_new, sched_process_free, sched_process_exit,
and sched_stat_wait.

The trace events converted to DEFINE_EVENT_PRINT:

sched_stat_sleep and sched_stat_iowait.

Note, since the TRACE_EVENT_TEMPLATE always uses a print, the
sched_stat_wait print format is defined in the template and this
template is used by sched_stat_sleep and sched_stat_iowait. But the
later two override the print format.
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

It is no longer set and scheduled to be removed.
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Inode permissions are much easier to understand if they are printed in
octal.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Add the facility for ext4_forget() to be called from
ext4_free_blocks().  This simplifies the code in a large number of
places, and centralizes most of the work of calling ext4_forget() into
a single place.

Also fix a bug in the extents migration code; it wasn't calling
ext4_forget() when releasing the indirect blocks during the
conversion.  As a result, if the system cashed during or shortly after
the extents migration, and the released indirect blocks get reused as
data blocks, the journal replay would corrupt the data blocks.  With
this new patch, fixing this bug was as simple as adding the
EXT4_FREE_BLOCKS_FORGET flags to the call to ext4_free_blocks().
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>

Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Lockdep events subsystem gathers various locking related events
such as a request, release, contention or acquisition of a lock.

The name of this event subsystem is a bit of a misnomer since
these events are not quite related to lockdep but more generally
to locking, ie: these events are not reporting lock dependencies
or possible deadlock scenario but pure locking events.

Hence this rename.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NHitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <1258103194-843-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Now that we can filter based on fields via perf record, people
will start using filter expressions and will expect them to
be obvious.

The primary way to see which fields are available is by looking
at the trace output, such as:

  gcc-18676 [000]   343.011728: irq_handler_entry: irq=0 handler=timer
  cc1-18677 [000]   343.012727: irq_handler_entry: irq=0 handler=timer
  cc1-18677 [000]   343.032692: irq_handler_entry: irq=0 handler=timer
  cc1-18677 [000]   343.033690: irq_handler_entry: irq=0 handler=timer
  cc1-18677 [000]   343.034687: irq_handler_entry: irq=0 handler=timer
  cc1-18677 [000]   343.035686: irq_handler_entry: irq=0 handler=timer
  cc1-18677 [000]   343.036684: irq_handler_entry: irq=0 handler=timer

While 'irq==0' filters work, the 'handler==<x>' filter expression
does not work:

  $ perf record -R -f -a -e irq:irq_handler_entry --filter handler=timer sleep 1
   Error: failed to set filter with 22 (Invalid argument)

The problem is that while an 'irq' field exists and is recognized
as a filter field - 'handler' does not exist - its name is 'name'
in the output.

To solve this, we need to synchronize the printout and the field
names, wherever possible.

In cases where the printout prints a non-field, we enclose
that information in square brackets, such as:

  perf-1380  [013]   724.903505: softirq_exit: vec=9 [action=RCU]
  perf-1380  [013]   724.904482: softirq_exit: vec=1 [action=TIMER]

This way users can use filter expressions more intuitively: all
fields that show up as 'primary' (non-bracketed) information is
filterable.

This patch harmonizes the field names for all irq, bkl, power,
sched and timer events.

We might in fact think about dropping the print format bit of
generic tracepoints altogether, and just print the fields that
are being recorded.

Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This approach is the first baby step towards solving many of the
structural problems the x86 MCE logging code is having today:

 - It has a private ring-buffer implementation that has a number
   of limitations and has been historically fragile and buggy.

 - It is using a quirky /dev/mcelog ioctl driven ABI that is MCE
   specific. /dev/mcelog is not part of any larger logging
   framework and hence has remained on the fringes for many years.

 - The MCE logging code is still very unclean partly due to its ABI
   limitations. Fields are being reused for multiple purposes, and
   the whole message structure is limited and x86 specific to begin
   with.

All in one, the x86 tree would like to move away from this private
implementation of an event logging facility to a broader framework.

By using perf events we gain the following advantages:

 - Multiple user-space agents can access MCE events. We can have an
   mcelog daemon running but also a system-wide tracer capturing
   important events in flight-recorder mode.

 - Sampling support: the kernel and the user-space call-chain of MCE
   events can be stored and analyzed as well. This way actual patterns
   of bad behavior can be matched to precisely what kind of activity
   happened in the kernel (and/or in the app) around that moment in
   time.

 - Coupling with other hardware and software events: the PMU can track a
   number of other anomalies - monitoring software might chose to
   monitor those plus the MCE events as well - in one coherent stream of
   events.

 - Discovery of MCE sources - tracepoints are enumerated and tools can
   act upon the existence (or non-existence) of various channels of MCE
   information.

 - Filtering support: we just subscribe to and act upon the events we
   are interested in. Then even on a per event source basis there's
   in-kernel filter expressions available that can restrict the amount
   of data that hits the event channel.

 - Arbitrary deep per cpu buffering of events - we can buffer 32
   entries or we can buffer as much as we want, as long as we have
   the RAM.

 - An NMI-safe ring-buffer implementation - mappable to user-space.

 - Built-in support for timestamping of events, PID markers, CPU
   markers, etc.

 - A rich ABI accessible over system call interface. Per cpu, per task
   and per workload monitoring of MCE events can be done this way. The
   ABI itself has a nice, meaningful structure.

 - Extensible ABI: new fields can be added without breaking tooling.
   New tracepoints can be added as the hardware side evolves. There's
   various parsers that can be used.

 - Lots of scheduling/buffering/batching modes of operandi for MCE
   events. poll() support. mmap() support. read() support. You name it.

 - Rich tooling support: even without any MCE specific extensions added
   the 'perf' tool today offers various views of MCE data: perf report,
   perf stat, perf trace can all be used to view logged MCE events and
   perhaps correlate them to certain user-space usage patterns. But it
   can be used directly as well, for user-space agents and policy action
   in mcelog, etc.

With this we hope to achieve significant code cleanup and feature
improvements in the MCE code, and we hope to be able to drop the
/dev/mcelog facility in the end.

This patch is just a plain dumb dump of mce_log() records to
the tracepoints / perf events framework - a first proof of
concept step.
Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <4AD42A0D.7050104@jp.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Since 2.6.31 now has request-based device-mapper, it's useful to have
a tracepoint for request-remapping as well as bio-remapping.
This patch adds a tracepoint for request-remapping, trace_block_rq_remap().
Signed-off-by: NKiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Since 2.6.31 now has request-based device-mapper, it's useful to have
a tracepoint for request-remapping as well as bio-remapping.
This patch adds a tracepoint for request-remapping, trace_block_rq_remap().
Signed-off-by: NKiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

The tracepoint ext4_da_write_pages has a struct mpage_da_data*
parameter, but that struct is only defined in fs/ext4/ext4.h.  This
patch adds a forward declaration for that struct, so this tracepoint
header can still be used by tools like SystemTap.

This is a continuation of the fix in commit 3661d286.

http://sourceware.org/bugzilla/show_bug.cgi?id=10703Signed-off-by: NJosh Stone <jistone@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The /proc/fs/jbd2/<dev>/history was maintained manually; by using
tracepoints, we can get all of the existing functionality of the /proc
file plus extra capabilities thanks to the ftrace infrastructure.  We
save memory as a bonus.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The /proc/fs/ext4/<dev>/mb_history was maintained manually, and had a
number of problems: it required a largish amount of memory to be
allocated for each ext4 filesystem, and the s_mb_history_lock
introduced a CPU contention problem.  

By ripping out the mb_history code and replacing it with ftrace
tracepoints, and we get more functionality: timestamps, event
filtering, the ability to correlate mballoc history with other ext4
tracepoints, etc.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Work around problems in the writeback code to force out writebacks in
larger chunks than just 4mb, which is just too small.  This also works
around limitations in the ext4 block allocator, which can't allocate
more than 2048 blocks at a time.  So we need to defeat the round-robin
characteristics of the writeback code and try to write out as many
blocks in one inode before allowing the writeback code to move on to
another inode.  We add a a new per-filesystem tunable,
max_writeback_mb_bump, which caps this to a default of 128mb per
inode.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Add two events lock_kernel and unlock_kernel() to trace the bkl uses.
This opens the door for userspace tools to perform statistics about
the callsites that use it, dependencies with other locks (by pairing
the trace with lock events), use with recursivity and so on...

The {__reacquire,release}_kernel_lock() events are not traced because
these are called from schedule, thus the sched events are sufficient
to trace them.

Example of a trace:

hald-addon-stor-4152  [000]   165.875501: unlock_kernel: depth: 0, fs/block_dev.c:1358 __blkdev_put()
hald-addon-stor-4152  [000]   167.832974: lock_kernel: depth: 0, fs/block_dev.c:1167 __blkdev_get()

How to get the callsites that acquire it recursively:

cd /debug/tracing/events/bkl
echo "lock_depth > 0" > filter

firefox-4951  [001]   206.276967: unlock_kernel: depth: 1, fs/reiserfs/super.c:575 reiserfs_dirty_inode()

You can also filter by file and/or line.

v2: Use of FILTER_PTR_STRING attribute for files and lines fields to
    make them traceable.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>

Using %pf instead of %pF supresses printing of the function offset
which will always be 0 in the case of worklet functions.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Zhaolei <zhaolei@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20090922024033.GB31801@kryten>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>