[PATCH 3/7] perf trace: Add usage of --no-syscalls in man page

From: Arnaldo Carvalho de Melo
Date: Thu Apr 13 2017 - 15:35:55 EST


From: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxxxxxxx>

perf trace supports --no-syscalls option but it's not listed in the man
page. (Though, I see an example using --no-syscalls in EXAMPLES
section.)

Committer note:

The --no-syscalls option tells 'perf trace' not to automagically ask for
raw_syscalls:sys_{enter,exit} to then format it in a strace like way.

This become more used as 'perf trace' got support for arbitrary events,
such as tracepoints, so more and more we use:

# perf trace --no-syscalls -e nmi:*
0.000 nmi:nmi_handler:perf_event_nmi_handler() delta_ns: 36649 handled: 1)
0.019 nmi:nmi_handler:nmi_cpu_backtrace_handler() delta_ns: 2907 handled: 0)
0.676 nmi:nmi_handler:perf_event_nmi_handler() delta_ns: 9401 handled: 1)
0.680 nmi:nmi_handler:nmi_cpu_backtrace_handler() delta_ns: 288 handled: 0)
0.701 nmi:nmi_handler:perf_event_nmi_handler() delta_ns: 4977 handled: 1)
0.703 nmi:nmi_handler:nmi_cpu_backtrace_handler() delta_ns: 67 handled: 0)
0.736 nmi:nmi_handler:perf_event_nmi_handler() delta_ns: 8549 handled: 1)
^C#

Signed-off-by: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Alexis Berlemont <alexis.berlemont@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1492063332-5745-1-git-send-email-ravi.bangoria@xxxxxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/Documentation/perf-trace.txt | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/Documentation/perf-trace.txt b/tools/perf/Documentation/perf-trace.txt
index afd728672b6f..c1e3288a2dfb 100644
--- a/tools/perf/Documentation/perf-trace.txt
+++ b/tools/perf/Documentation/perf-trace.txt
@@ -123,7 +123,8 @@ the thread executes on the designated CPUs. Default is to monitor all CPUs.
major or all pagefaults. Default value is maj.

--syscalls::
- Trace system calls. This options is enabled by default.
+ Trace system calls. This options is enabled by default, disable with
+ --no-syscalls.

--call-graph [mode,type,min[,limit],order[,key][,branch]]::
Setup and enable call-graph (stack chain/backtrace) recording.
--
2.9.3