1. 07 Apr, 2009 11 commits
    • Bart Van Assche's avatar
      branch tracer: Fix for enabling branch profiling makes sparse unusable · d9ad8bc0
      Bart Van Assche authored
      One of the changes between kernels 2.6.28 and 2.6.29 is that a branch profiler
      has been added for if() statements. Unfortunately this patch makes the sparse
      output unusable with CONFIG_TRACE_BRANCH_PROFILING=y: when branch profiling is
      enabled, sparse prints so much false positives that the real issues are no
      longer visible. This behavior can be reproduced as follows:
      * enable CONFIG_TRACE_BRANCH_PROFILING, e.g. by running make allyesconfig or
        make allmodconfig.
      * run make C=2
      
      Result: a huge number of the following sparse warnings.
      ...
      include/linux/cpumask.h:547:2: warning: symbol '______r' shadows an earlier one
      include/linux/cpumask.h:547:2: originally declared here
      ...
      
      The patch below fixes this by disabling branch profiling while analyzing the
      kernel code with sparse.
      
      See also:
      * http://lkml.org/lkml/2008/11/21/18
      * http://bugzilla.kernel.org/show_bug.cgi?id=12925Signed-off-by: default avatarBart Van Assche <bart.vanassche@gmail.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Steven Rostedt <srostedt@redhat.com>
      LKML-Reference: <200904051620.02311.bart.vanassche@gmail.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      d9ad8bc0
    • Zhaolei's avatar
      ftrace: Correct a text align for event format output · 1bbe2a83
      Zhaolei authored
      If we cat debugfs/tracing/events/ftrace/bprint/format, we'll see:
      name: bprint
      ID: 6
      format:
      	field:unsigned char common_type;	offset:0;	size:1;
      	field:unsigned char common_flags;	offset:1;	size:1;
      	field:unsigned char common_preempt_count;	offset:2;	size:1;
      	field:int common_pid;	offset:4;	size:4;
      	field:int common_tgid;	offset:8;	size:4;
      
      	field:unsigned long ip;	offset:12;	size:4;
      	field:char * fmt;	offset:16;	size:4;
      	field: char buf;	offset:20;	size:0;
      
      print fmt: "%08lx (%d) fmt:%p %s"
      
      There is an inconsistent blank before char buf.
      Signed-off-by: default avatarZhao Lei <zhaolei@cn.fujitsu.com>
      LKML-Reference: <49D5E3EE.70201@cn.fujitsu.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      1bbe2a83
    • Nikanth Karthikesan's avatar
      Update /debug/tracing/README · bc2b6871
      Nikanth Karthikesan authored
      Some of the tracers have been renamed, which was not updated in the in-kernel
      run-time README file. Update it.
      Signed-off-by: default avatarNikanth Karthikesan <knikanth@suse.de>
      LKML-Reference: <200903231158.32151.knikanth@suse.de>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      bc2b6871
    • Frederic Weisbecker's avatar
      tracing/ftrace: alloc the started cpumask for the trace file · b0dfa978
      Frederic Weisbecker authored
      Impact: fix a crash while cat trace file
      
      Currently we are using a cpumask to remind each cpu where a
      trace occured. It lets us notice the user that a cpu just had
      its first trace.
      
      But on latest -tip we have the following crash once we cat the trace
      file:
      
      IP: [<c0270c4a>] print_trace_fmt+0x45/0xe7
      *pde = 00000000
      Oops: 0000 [#1] PREEMPT SMP
      last sysfs file: /sys/class/net/eth0/carrier
      Pid: 3897, comm: cat Not tainted (2.6.29-tip-02825-g0f22972-dirty #81)
      EIP: 0060:[<c0270c4a>] EFLAGS: 00010297 CPU: 0
      EIP is at print_trace_fmt+0x45/0xe7
      EAX: 00000000 EBX: 00000000 ECX: c12d9e98 EDX: ccdb7010
      ESI: d31f4000 EDI: 00322401 EBP: d31f3f10 ESP: d31f3efc
      DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
      Process cat (pid: 3897, ti=d31f2000 task=d3b3cf20 task.ti=d31f2000)
      Stack:
      d31f4080 ccdb7010 d31f4000 d691fe70 ccdb7010 d31f3f24 c0270e5c d31f4000
      d691fe70 d31f4000 d31f3f34 c02718e8 c12d9e98 d691fe70 d31f3f70 c02bfc33
      00001000 09130000 d3b46e00 d691fe98 00000000 00000079 00000001 00000000
      Call Trace:
      [<c0270e5c>] ? print_trace_line+0x170/0x17c
      [<c02718e8>] ? s_show+0xa7/0xbd
      [<c02bfc33>] ? seq_read+0x24a/0x327
      [<c02bf9e9>] ? seq_read+0x0/0x327
      [<c02ab18b>] ? vfs_read+0x86/0xe1
      [<c02ab289>] ? sys_read+0x40/0x65
      [<c0202d8f>] ? sysenter_do_call+0x12/0x3c
      Code: 00 00 00 89 45 ec f7 c7 00 20 00 00 89 55 f0 74 4e f6 86 98 10 00 00 02 74 45 8b 86 8c 10 00 00 8b 9e a8 10 00 00 e8 52 f3 ff ff <0f> a3 03 19 c0 85 c0 75 2b 8b 86 8c 10 00 00 8b 9e a8 10 00 00
      EIP: [<c0270c4a>] print_trace_fmt+0x45/0xe7 SS:ESP 0068:d31f3efc
      CR2: 0000000000000000
      ---[ end trace aa9cf38e5ebed9dd ]---
      
      This is because we alloc the iter->started cpumask on tracing_pipe_open but
      not on tracing_open.
      
      It hadn't been noticed until now because we need to have ring buffer overruns
      to activate the starting of cpu buffer detection.
      
      Also, we need a check to not print the messagge for the first trace on the file.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <1238619188-6109-1-git-send-email-fweisbec@gmail.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      b0dfa978
    • Huang Weiyi's avatar
      tracing, x86: remove duplicated #include · 5ab8026a
      Huang Weiyi authored
      Remove duplicated #include in arch/x86/kernel/ftrace.c.
      Signed-off-by: default avatarHuang Weiyi <weiyi.huang@gmail.com>
      LKML-Reference: <1238503291-2532-1-git-send-email-weiyi.huang@gmail.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      5ab8026a
    • Zhaolei's avatar
      ftrace: Add check of sched_stopped for probe_sched_wakeup · 8bcae09b
      Zhaolei authored
      The wakeup tracing in sched_switch does not stop when a user
      disables tracing. This is because the probe_sched_wakeup() is missing
      the check to prevent the wakeup from being traced.
      Signed-off-by: default avatarZhao Lei <zhaolei@cn.fujitsu.com>
      LKML-Reference: <49D1C543.3010307@cn.fujitsu.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      8bcae09b
    • Steven Rostedt's avatar
      function-graph: add proper initialization for init task · 5ac9f622
      Steven Rostedt authored
      Impact: fix to crash going to kexec
      
      The init task did not properly initialize the function graph pointers.
      Altough these pointers are NULL, they can not be assumed to be NULL
      for the init task, and must still be properly initialize.
      
      This usually is not an issue since a problem only arises when a task
      exits, and the init tasks do not usually exit. But when doing tests
      with kexec, the init tasks do exit, and the bug appears.
      
      This patch properly initializes the init tasks function graph data
      structures.
      Reported-and-Tested-by: default avatarYinghai Lu <yinghai@kernel.org>
      LKML-Reference: <alpine.DEB.2.00.0903252053080.5675@gandalf.stny.rr.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      5ac9f622
    • Frederic Weisbecker's avatar
      tracing/ftrace: fix missing include string.h · 5f0c6c03
      Frederic Weisbecker authored
      Building a kernel with tracing can raise the following warning on
      tip/master:
      
      kernel/trace/trace.c:1249: error: implicit declaration of function 'vbin_printf'
      
      We are missing an include to string.h
      Reported-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <1238160130-7437-1-git-send-email-fweisbec@gmail.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      5f0c6c03
    • Lai Jiangshan's avatar
      tracing: fix incorrect return type of ns2usecs() · cf8e3474
      Lai Jiangshan authored
      Impact: fix time output bug in 32bits system
      
      ns2usecs() returns 'long', it's incorrect.
      
      (In i386)
      ...
                <idle>-0     [000]   521.442100: _spin_lock <-tick_do_update_jiffies64
                <idle>-0     [000]   521.442101: do_timer <-tick_do_update_jiffies64
                <idle>-0     [000]   521.442102: update_wall_time <-do_timer
                <idle>-0     [000]   521.442102: update_xtime_cache <-update_wall_time
      ....
      (It always print the time less than 2200 seconds besides ...)
      Because 'long' is 32bits in i386. ( (1<<31) useconds is about 2200 seconds)
      
      ...
                <idle>-0     [001] 4154502640.134759: rcu_bh_qsctr_inc <-__do_softirq
                <idle>-0     [001] 4154502640.134760: _local_bh_enable <-__do_softirq
                <idle>-0     [001] 4154502640.134761: idle_cpu <-irq_exit
      ...
      (very large value)
      Because 'long' is a signed type and it is 32bits in i386.
      
      Changes in v2:
      return 'unsigned long long' instead of 'cycle_t'
      Signed-off-by: default avatarLai Jiangshan <laijs@cn.fujitsu.com>
      LKML-Reference: <49D05D10.4030009@cn.fujitsu.com>
      Reported-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
      Acked-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      cf8e3474
    • 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
  2. 03 Apr, 2009 3 commits
  3. 01 Apr, 2009 1 commit
  4. 31 Mar, 2009 13 commits
  5. 30 Mar, 2009 1 commit
  6. 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
  7. 25 Mar, 2009 6 commits
  8. 24 Mar, 2009 4 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