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  1. 07 Apr, 2009 2 commits
    • Steven Rostedt's avatar
      tracing: remove CALLER_ADDR2 from wakeup tracer · 301fd748
      Steven Rostedt authored 
      Maneesh Soni was getting a crash when running the wakeup tracer.
We debugged it down to the recording of the function with the
CALLER_ADDR2 macro.  This is used to get the location of the caller
to schedule.

But the problem comes when schedule is called by assmebly. In the case
that Maneesh had, retint_careful would call schedule. But retint_careful
does not set up a proper frame pointer. CALLER_ADDR2 is defined as
__builtin_return_address(2). This produces the following assembly in
the wakeup tracer code.

   mov    0x0(%rbp),%rcx  <--- get the frame pointer of the caller
   mov    %r14d,%r8d
   mov    0xf2de8e(%rip),%rdi

   mov    0x8(%rcx),%rsi  <-- this is __builtin_return_address(1)
   mov    0x28(%rdi,%rax,8),%rbx

   mov    (%rcx),%rax  <-- get the frame pointer of the caller's caller
   mov    %r12,%rcx
   mov    0x8(%rax),%rdx <-- this is __builtin_return_address(2)

At the reading of 0x8(%rax) Maneesh's machine would take a fault.
The reason is that retint_careful did not set up the return address
and the content of %rax here was zero.

To verify this, I sent Maneesh a patch to create a frame pointer
in retint_careful. He ran the test again but this time he would take
the same type of fault from sysret_careful. The retint_careful was no
longer an issue, but there are other callers that still have issues.

Instead of adding frame pointers for all callers to schedule (in possibly
all archs), it is much safer to simply not use CALLER_ADDR2. This
loses out on knowing what called schedule, but the function tracer
will help there if needed.
Reported-by: default avatarManeesh Soni <maneesh@in.ibm.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      301fd748
    • Ingo Molnar's avatar
      Merge branch 'tracing/blktrace-fixes' into tracing/urgent · a053958f
      Ingo Molnar authored 
      Merge reason: this used to be a tracing/blktrace-v2 devel topic still
              cooking during the merge window - has propagated to fixes
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      a053958f
  3. 03 Apr, 2009 3 commits
    • Li Zefan's avatar
      blktrace: fix pdu_len when tracing packet command requests · e2494e1b
      Li Zefan authored 
      Impact: output all of packet commands - not just the first 4 / 8 bytes

Since commit d7e3c324 ("block: add
large command support"), struct request->cmd has been changed from
unsinged char cmd[BLK_MAX_CDB] to unsigned char *cmd.

v1 -> v2: by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

- make sure rq->cmd_len is always intialized, and then we can use
  rq->cmd_len instead of BLK_MAX_CDB.
Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Acked-by: default avatarFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
LKML-Reference: <49D4507E.2060602@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      e2494e1b
    • Li Zefan's avatar
      blktrace: small cleanup in blk_msg_write() · 7635b03a
      Li Zefan authored 
      Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "Alan D. Brunelle" <alan.brunelle@hp.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
LKML-Reference: <49D5BB56.7000807@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      7635b03a
    • Carl Henrik Lunde's avatar
      blktrace: NUL-terminate user space messages · a4b3ada8
      Carl Henrik Lunde authored 
      Impact: fix corrupted blkparse output

Make sure messages from user space are NUL-terminated strings,
otherwise we could dump random memory to the block trace file.

Additionally, I've limited the message to BLK_TN_MAX_MSG-1
characters, because the last character would be stripped by
vscnprintf anyway.
Signed-off-by: default avatarCarl Henrik Lunde <chlunde@ping.uio.no>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "Alan D. Brunelle" <alan.brunelle@hp.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20090403122714.GT5178@kernel.dk>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      a4b3ada8
  5. 01 Apr, 2009 1 commit
  7. 31 Mar, 2009 13 commits
  9. 30 Mar, 2009 1 commit
  11. 26 Mar, 2009 1 commit
    • Tom Zanussi's avatar
      tracing: filter fix for TRACE_EVENT_FORMAT events · 9a8118ba
      Tom Zanussi authored 
      Impact: fix crash (hang) when using TRACE_EVENT_FORMAT filter files

filters are only hooked up to the tracepoint events defined using
TRACE_EVENT but not the tracers that use TRACE_EVENT_FORMAT, such
as ftrace.

Do not display the filter files at all for TRACE_EVENT_FORMAT events
for the time being.

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: =?ISO-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1237878882.8339.61.camel@charm-linux>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      9a8118ba
  13. 25 Mar, 2009 6 commits
  15. 24 Mar, 2009 13 commits
    • Jody McIntyre's avatar
      tracing: Documentation / sample code fixes for tracepoints · 0a5d6490
      Jody McIntyre authored 
      Fix the tracepoint documentation to refer to "tracepoint-sample"
instead of "tracepoint-example" to match what actually exists;
fix the directory, and clarify how to compile.

Change every instance of "example" in the sample tracepoint code
to "sample" for consistency.
Signed-off-by: default avatarJody McIntyre <scjody@sun.com>
Acked-by: default avatarMathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: torvalds@linux-foundation.org
LKML-Reference: <20090324200027.GH8294@clouds>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      0a5d6490
    • Lai Jiangshan's avatar
      tracing: use union for multi-usages field · ee000b7f
      Lai Jiangshan authored 
      Impact: cleanup

struct dyn_ftrace::ip has different usages in his lifecycle,
we use union for it. And also for struct dyn_ftrace::flags.
Signed-off-by: default avatarLai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <49C871BE.3080405@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      ee000b7f
    • Lai Jiangshan's avatar
      ftrace: show virtual PID · cc59c9e8
      Lai Jiangshan authored 
      Impact: fix PID output under namespaces

When current namespace is not the global namespace,
pid read from set_ftrace_pid is no correct.

 # ~/newpid_namespace_run bash
 # echo $$
 1
 # echo 1 > set_ftrace_pid
 # cat set_ftrace_pid
 3756

Since we write virtual PID to set_ftrace_pid, we need get
virtual PID when we read it.
Signed-off-by: default avatarLai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <49C84D65.9050606@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      cc59c9e8
    • Steven Rostedt's avatar
      function-graph: add option for include sleep times · be6f164a
      Steven Rostedt authored 
      Impact: give user a choice to show times spent while sleeping

The user may want to see the time a function spent sleeping.
This patch adds the trace option "sleep-time" to allow that.
The "sleep-time" option is default on.

 echo sleep-time > /debug/tracing/trace_options

produces:

 ------------------------------------------
 2)  avahi-d-3428  =>    <idle>-0
 ------------------------------------------

 2)               |      finish_task_switch() {
 2)   0.621 us    |        _spin_unlock_irq();
 2)   2.202 us    |      }
 2) ! 1002.197 us |    }
 2) ! 1003.521 us |  }

where as,

 echo nosleep-time > /debug/tracing/trace_options

produces:

 0)    <idle>-0    =>  yum-upd-3416
 ------------------------------------------

 0)               |              finish_task_switch() {
 0)   0.643 us    |                _spin_unlock_irq();
 0)   2.342 us    |              }
 0) + 41.302 us   |            }
 0) + 42.453 us   |          }
Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      be6f164a
    • Steven Rostedt's avatar
      function-graph: ignore times across schedule · 8aef2d28
      Steven Rostedt authored 
      Impact: more accurate timings

The current method of function graph tracing does not take into
account the time spent when a task is not running. This shows functions
that call schedule have increased costs:

 3) + 18.664 us   |      }
 ------------------------------------------
 3)    <idle>-0    =>  kblockd-123
 ------------------------------------------

 3)               |      finish_task_switch() {
 3)   1.441 us    |        _spin_unlock_irq();
 3)   3.966 us    |      }
 3) ! 2959.433 us |    }
 3) ! 2961.465 us |  }

This patch uses the tracepoint in the scheduling context switch to
account for time that has elapsed while a task is scheduled out.
Now we see:

 ------------------------------------------
 3)    <idle>-0    =>  edac-po-1067
 ------------------------------------------

 3)               |      finish_task_switch() {
 3)   0.685 us    |        _spin_unlock_irq();
 3)   2.331 us    |      }
 3) + 41.439 us   |    }
 3) + 42.663 us   |  }
Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      8aef2d28
    • Steven Rostedt's avatar
      function-graph: prevent more than one tracer registering · 05ce5818
      Steven Rostedt authored 
      Impact: prevent crash due to multiple function graph tracers

The function graph tracer can currently only handle a single tracer
being registered. If another tracer registers with the function
graph tracer it can crash the system.
Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      05ce5818
    • Steven Rostedt's avatar
      function-graph: moved the timestamp from arch to generic code · 5d1a03dc
      Steven Rostedt authored 
      This patch move the timestamp from happening in the arch specific
code into the general code. This allows for better control by the tracer
to time manipulation.
Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      5d1a03dc
    • Steven Rostedt's avatar
      tracing: fix memory leak in trace_stat · 09833521
      Steven Rostedt authored 
      If the function profiler does not have any items recorded and one were
to cat the function stat file, the kernel would take a BUG with a NULL
pointer dereference.

Looking further into this, I found that returning NULL from stat_start
did not stop the stat logic, and would later call stat_next. This breaks
from the way seq_file works, so I looked into fixing the stat code.

This is where I noticed that the last next_entry is never freed.
It is allocated, and if the stat_next returns NULL, the code breaks out
of the loop, unlocks the mutex and exits. We never link the next_entry
nor do we free it. Thus it is a real memory leak.

This patch rearranges the code a bit to not only fix the memory leak,
but also to act more like seq_file where nothing is printed if there
is nothing to print. That is, stat_start returns NULL.
Signed-off-by: default avatarSteven Rostedt <srostedt@redhat.com>
      09833521
    • Li Zefan's avatar
      blktrace: print human-readable act_mask · 09341997
      Li Zefan authored 
      Impact: new feature, allow symbolic values in /debug/tracing/act_mask

Print stringified act_mask instead of hex value:

 # cat act_mask
 read,write,barrier,sync,queue,requeue,issue,complete,fs,pc,ahead,meta,
 discard,drv_data
 # echo "meta,write" > act_mask
 # cat act_mask
 write,meta

Also:
 - make act_mask accept "ahead", "meta", "discard" and "drv_data"
 - use strsep() instead of strchr() to parse user input
 - return -EINVAL if a token is not found in the mask map
 - fix a bug that 'value' is unsigned, so it can < 0
 - propagate error value of blk_trace_mask2str() to userspace, but not
   always return -ENXIO.
Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Acked-by: default avatarJens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <49C8AB42.1000802@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      09341997
    • Li Zefan's avatar
      blktrace: fix t_error() · e0dc81be
      Li Zefan authored 
      Impact: fix error flag output

t_error() should return t->error but not t->sector.
Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Acked-by: default avatarJens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <49C8945F.5020802@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      e0dc81be
    • Li Zefan's avatar
      blktrace: fix wrong calculation of RWBS · 65796348
      Li Zefan authored 
      Impact: fix the output of IO type category characters

Trace categories are the upper 16 bits, not the lower 16 bits.
Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Acked-by: default avatarJens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <49C89432.8010805@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      65796348
    • Li Zefan's avatar
      blktrace: mark ddir_act[] const · e4955c99
      Li Zefan authored 
      Impact: cleanup

ddir_act and what2act always stay immutable.
Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
Acked-by: default avatarJens Axboe <jens.axboe@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <49C89415.5080503@cn.fujitsu.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      e4955c99
    • Tom Zanussi's avatar
      tracing/filters: disallow integer values for string filters and vice versa · 9f58a159
      Tom Zanussi authored 
      Impact: fix filter use boundary condition / crash

Make sure filters for string fields don't use integer values and vice
versa.  Getting it wrong can crash the system or produce bogus
results.
Signed-off-by: default avatarTom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: =?ISO-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1237878882.8339.61.camel@charm-linux>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      9f58a159
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