![Robert Richter](/assets/img/avatar_default.png)
The default input file for perf report is not handled the same way as perf record does it for its output file. This leads to unexpected behavior of perf report, etc. E.g.: # perf record -a -e cpu-cycles sleep 2 | perf report | cat failed to open perf.data: No such file or directory (try 'perf record' first) While perf record writes to a fifo, perf report expects perf.data to be read. This patch changes this to accept fifos as input file. Applies to the following commands: perf annotate perf buildid-list perf evlist perf kmem perf lock perf report perf sched perf script perf timechart Also fixes char const* -> const char* type declaration for filename strings. v2: * Prevent potential null pointer access to input_name in builtin-report.c. Needed due to removal of patch "perf report: Setup browser if stdout is a pipe" Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1323248577-11268-5-git-send-email-robert.richter@amd.com Signed-off-by: Robert Richter <robert.richter@amd.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
56 lines
1.5 KiB
Plaintext
56 lines
1.5 KiB
Plaintext
perf-sched(1)
|
|
==============
|
|
|
|
NAME
|
|
----
|
|
perf-sched - Tool to trace/measure scheduler properties (latencies)
|
|
|
|
SYNOPSIS
|
|
--------
|
|
[verse]
|
|
'perf sched' {record|latency|map|replay|script}
|
|
|
|
DESCRIPTION
|
|
-----------
|
|
There are five variants of perf sched:
|
|
|
|
'perf sched record <command>' to record the scheduling events
|
|
of an arbitrary workload.
|
|
|
|
'perf sched latency' to report the per task scheduling latencies
|
|
and other scheduling properties of the workload.
|
|
|
|
'perf sched script' to see a detailed trace of the workload that
|
|
was recorded (aliased to 'perf script' for now).
|
|
|
|
'perf sched replay' to simulate the workload that was recorded
|
|
via perf sched record. (this is done by starting up mockup threads
|
|
that mimic the workload based on the events in the trace. These
|
|
threads can then replay the timings (CPU runtime and sleep patterns)
|
|
of the workload as it occurred when it was recorded - and can repeat
|
|
it a number of times, measuring its performance.)
|
|
|
|
'perf sched map' to print a textual context-switching outline of
|
|
workload captured via perf sched record. Columns stand for
|
|
individual CPUs, and the two-letter shortcuts stand for tasks that
|
|
are running on a CPU. A '*' denotes the CPU that had the event, and
|
|
a dot signals an idle CPU.
|
|
|
|
OPTIONS
|
|
-------
|
|
-i::
|
|
--input=<file>::
|
|
Input file name. (default: perf.data unless stdin is a fifo)
|
|
|
|
-v::
|
|
--verbose::
|
|
Be more verbose. (show symbol address, etc)
|
|
|
|
-D::
|
|
--dump-raw-trace=::
|
|
Display verbose dump of the sched data.
|
|
|
|
SEE ALSO
|
|
--------
|
|
linkperf:perf-record[1]
|