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There's a bug that perf report sometimes ignore some options on --stdio
output. This bug is triggered only if a related config variable is set.
For example, let's assume we have a following config file.
$ cat ~/.perfconfig
[call-graph]
print-type = graph
[hist]
percentage = absolute
Then, following perf config will not honor some options.
$ perf record -ag sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.199 MB perf.data (77 samples) ]
$ perf report -g none --stdio
# To display the perf.data header info, please use --header/--header-only options.
#
# Samples: 77 of event 'cycles'
# Event count (approx.): 25425383
#
# Overhead Command Shared Object Symbol
# ........ ............... ....................... ..............
#
16.34% swapper [kernel.vmlinux] [k] intel_idle
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---intel_idle
cpuidle_enter_state
cpuidle_enter
cpu_startup_entry
...
With '-g none' option, it should not show callchains, but it still shows
callchains. However it works as expected on --tui output.
Similarly, '--percentage relative' option is not work and still shows a
absolute percentage values.
Looking at the source, I found that those setting were overwritten by
config variables when setup_pager() called. The setup_pager() is to
start a pager process so that it can manage long lines of output on the
stdio mode. But as it calls the perf_config() after parsing arguments,
the settings were overwritten regardless of command line options.
The reason it calls perf_config() is to find the 'pager_program' which
might be set by a config variable, I guess. However current perf code
does not provide the config variable for it, so it's just meaningless
IMHO. Eliminating the call makes the option working as expected.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Taeung Song <treeze.taeung@gmail.com>
Link: http://lkml.kernel.org/r/1431529406-6762-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
96 lines
1.8 KiB
C
96 lines
1.8 KiB
C
#include "cache.h"
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#include "run-command.h"
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#include "sigchain.h"
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/*
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* This is split up from the rest of git so that we can do
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* something different on Windows.
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*/
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static int spawned_pager;
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static void pager_preexec(void)
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{
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/*
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* Work around bug in "less" by not starting it until we
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* have real input
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*/
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fd_set in;
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FD_ZERO(&in);
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FD_SET(0, &in);
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select(1, &in, NULL, &in, NULL);
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setenv("LESS", "FRSX", 0);
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}
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static const char *pager_argv[] = { "sh", "-c", NULL, NULL };
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static struct child_process pager_process;
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static void wait_for_pager(void)
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{
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fflush(stdout);
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fflush(stderr);
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/* signal EOF to pager */
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close(1);
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close(2);
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finish_command(&pager_process);
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}
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static void wait_for_pager_signal(int signo)
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{
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wait_for_pager();
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sigchain_pop(signo);
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raise(signo);
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}
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void setup_pager(void)
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{
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const char *pager = getenv("PERF_PAGER");
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if (!isatty(1))
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return;
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if (!pager)
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pager = getenv("PAGER");
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if (!(pager || access("/usr/bin/pager", X_OK)))
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pager = "/usr/bin/pager";
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if (!(pager || access("/usr/bin/less", X_OK)))
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pager = "/usr/bin/less";
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if (!pager)
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pager = "cat";
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if (!*pager || !strcmp(pager, "cat"))
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return;
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spawned_pager = 1; /* means we are emitting to terminal */
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/* spawn the pager */
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pager_argv[2] = pager;
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pager_process.argv = pager_argv;
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pager_process.in = -1;
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pager_process.preexec_cb = pager_preexec;
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if (start_command(&pager_process))
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return;
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/* original process continues, but writes to the pipe */
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dup2(pager_process.in, 1);
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if (isatty(2))
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dup2(pager_process.in, 2);
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close(pager_process.in);
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/* this makes sure that the parent terminates after the pager */
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sigchain_push_common(wait_for_pager_signal);
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atexit(wait_for_pager);
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}
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int pager_in_use(void)
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{
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const char *env;
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if (spawned_pager)
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return 1;
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env = getenv("PERF_PAGER_IN_USE");
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return env ? perf_config_bool("PERF_PAGER_IN_USE", env) : 0;
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}
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