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Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

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* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (172 commits)
  perf_event, amd: Fix spinlock initialization
  perf_event: Fix preempt warning in perf_clock()
  perf tools: Flush maps on COMM events
  perf_events, x86: Split PMU definitions into separate files
  perf annotate: Handle samples not at objdump output addr boundaries
  perf_events, x86: Remove superflous MSR writes
  perf_events: Simplify code by removing cpu argument to hw_perf_group_sched_in()
  perf_events, x86: AMD event scheduling
  perf_events: Add new start/stop PMU callbacks
  perf_events: Report the MMAP pgoff value in bytes
  perf annotate: Defer allocating sym_priv->hist array
  perf symbols: Improve debugging information about symtab origins
  perf top: Use a macro instead of a constant variable
  perf symbols: Check the right return variable
  perf/scripts: Tag syscall_name helper as not yet available
  perf/scripts: Add perf-trace-python Documentation
  perf/scripts: Remove unnecessary PyTuple resizes
  perf/scripts: Add syscall tracing scripts
  perf/scripts: Add Python scripting engine
  perf/scripts: Remove check-perf-trace from listed scripts
  ...

Fix trivial conflict in tools/perf/util/probe-event.c
This commit is contained in:
Linus Torvalds
2010-02-28 10:20:25 -08:00
parent e0d272429a 1dd2980d99
commit 6556a67435
131 changed files with 8522 additions and 3397 deletions
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57
Documentation/trace/kprobetrace.txt
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@ -24,6 +24,7 @@ Synopsis of kprobe_events
-------------------------
p[:[GRP/]EVENT] SYMBOL[+offs]|MEMADDR [FETCHARGS] : Set a probe
r[:[GRP/]EVENT] SYMBOL[+0] [FETCHARGS] : Set a return probe
-:[GRP/]EVENT : Clear a probe
GRP : Group name. If omitted, use "kprobes" for it.
EVENT : Event name. If omitted, the event name is generated
@ -37,15 +38,12 @@ Synopsis of kprobe_events
@SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol)
$stackN : Fetch Nth entry of stack (N >= 0)
$stack : Fetch stack address.
$argN : Fetch function argument. (N >= 0)(*)
$retval : Fetch return value.(**)
+|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(***)
$retval : Fetch return value.(*)
+|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**)
NAME=FETCHARG: Set NAME as the argument name of FETCHARG.
(*) aN may not correct on asmlinkaged functions and at the middle of
function body.
(**) only for return probe.
(***) this is useful for fetching a field of data structures.
(*) only for return probe.
(**) this is useful for fetching a field of data structures.
Per-Probe Event Filtering
@ -82,13 +80,16 @@ Usage examples
To add a probe as a new event, write a new definition to kprobe_events
as below.
echo p:myprobe do_sys_open dfd=$arg0 filename=$arg1 flags=$arg2 mode=$arg3 > /sys/kernel/debug/tracing/kprobe_events
echo 'p:myprobe do_sys_open dfd=%ax filename=%dx flags=%cx mode=+4($stack)' > /sys/kernel/debug/tracing/kprobe_events
This sets a kprobe on the top of do_sys_open() function with recording
1st to 4th arguments as "myprobe" event. As this example shows, users can
choose more familiar names for each arguments.
1st to 4th arguments as "myprobe" event. Note, which register/stack entry is
assigned to each function argument depends on arch-specific ABI. If you unsure
the ABI, please try to use probe subcommand of perf-tools (you can find it
under tools/perf/).
As this example shows, users can choose more familiar names for each arguments.
echo r:myretprobe do_sys_open $retval >> /sys/kernel/debug/tracing/kprobe_events
echo 'r:myretprobe do_sys_open $retval' >> /sys/kernel/debug/tracing/kprobe_events
This sets a kretprobe on the return point of do_sys_open() function with
recording return value as "myretprobe" event.
@ -97,23 +98,24 @@ recording return value as "myretprobe" event.
cat /sys/kernel/debug/tracing/events/kprobes/myprobe/format
name: myprobe
ID: 75
ID: 780
format:
field:unsigned short common_type; offset:0; size:2;
field:unsigned char common_flags; offset:2; size:1;
field:unsigned char common_preempt_count; offset:3; size:1;
field:int common_pid; offset:4; size:4;
field:int common_tgid; offset:8; size:4;
field:unsigned short common_type; offset:0; size:2; signed:0;
field:unsigned char common_flags; offset:2; size:1; signed:0;
field:unsigned char common_preempt_count; offset:3; size:1;signed:0;
field:int common_pid; offset:4; size:4; signed:1;
field:int common_lock_depth; offset:8; size:4; signed:1;
field: unsigned long ip; offset:16;tsize:8;
field: int nargs; offset:24;tsize:4;
field: unsigned long dfd; offset:32;tsize:8;
field: unsigned long filename; offset:40;tsize:8;
field: unsigned long flags; offset:48;tsize:8;
field: unsigned long mode; offset:56;tsize:8;
field:unsigned long __probe_ip; offset:12; size:4; signed:0;
field:int __probe_nargs; offset:16; size:4; signed:1;
field:unsigned long dfd; offset:20; size:4; signed:0;
field:unsigned long filename; offset:24; size:4; signed:0;
field:unsigned long flags; offset:28; size:4; signed:0;
field:unsigned long mode; offset:32; size:4; signed:0;
print fmt: "(%lx) dfd=%lx filename=%lx flags=%lx mode=%lx", REC->ip, REC->dfd, REC->filename, REC->flags, REC->mode
print fmt: "(%lx) dfd=%lx filename=%lx flags=%lx mode=%lx", REC->__probe_ip,
REC->dfd, REC->filename, REC->flags, REC->mode
You can see that the event has 4 arguments as in the expressions you specified.
@ -121,6 +123,12 @@ print fmt: "(%lx) dfd=%lx filename=%lx flags=%lx mode=%lx", REC->ip, REC->dfd, R
This clears all probe points.
Or,
echo -:myprobe >> kprobe_events
This clears probe points selectively.
Right after definition, each event is disabled by default. For tracing these
events, you need to enable it.
@ -146,4 +154,3 @@ events, you need to enable it.
returns from SYMBOL(e.g. "sys_open+0x1b/0x1d <- do_sys_open" means kernel
returns from do_sys_open to sys_open+0x1b).