From 56f3bae70638b33477a6015fd362ccfe354fd3ee Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Wed, 7 Sep 2011 17:14:00 -0600 Subject: [PATCH] perf stat: Add --log-fd option to redirect stderr elsewhere This perf stat option emulates valgrind's --log-fd option, allowing the user to send perf results elsewhere, and leaving stderr for use by the program under test. This complements --output file option, and is mutually exclusive with it. 3>results perf stat --log-fd 3 -- $cmd 3>>results perf stat --log-fd 3 --append -- $cmd The perl distro's make test.valgrind target uses valgrind's --log-fd option, I've adapted it to invoke perf also, and tested this patch there. Link: http://lkml.kernel.org/r/1315437244-3788-2-git-send-email-jim.cromie@gmail.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Jim Cromie Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-stat.txt | 11 ++++++++++- tools/perf/builtin-stat.c | 14 ++++++++++++++ 2 files changed, 24 insertions(+), 1 deletion(-) diff --git a/tools/perf/Documentation/perf-stat.txt b/tools/perf/Documentation/perf-stat.txt index 08394c4879a..8966b9ab201 100644 --- a/tools/perf/Documentation/perf-stat.txt +++ b/tools/perf/Documentation/perf-stat.txt @@ -95,12 +95,21 @@ corresponding events, i.e., they always refer to events defined earlier on the c line. -o file:: --output file:: +--output file:: Print the output into the designated file. --append:: Append to the output file designated with the -o option. Ignored if -o is not specified. +--log-fd:: + +Log output to fd, instead of stderr. Complementary to --output, and mutually exclusive +with it. --append may be used here. Examples: + 3>results perf stat --log-fd 3 -- $cmd + 3>>results perf stat --log-fd 3 --append -- $cmd + + + EXAMPLES -------- diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index bec64a9e741..a43c6805107 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -196,6 +196,7 @@ static bool csv_output = false; static bool group = false; static const char *output_name = NULL; static FILE *output = NULL; +static int output_fd; static volatile int done = 0; @@ -1080,6 +1081,8 @@ static const struct option options[] = { OPT_STRING('o', "output", &output_name, "file", "output file name"), OPT_BOOLEAN(0, "append", &append_file, "append to the output file"), + OPT_INTEGER(0, "log-fd", &output_fd, + "log output to fd, instead of stderr"), OPT_END() }; @@ -1166,6 +1169,10 @@ int cmd_stat(int argc, const char **argv, const char *prefix __used) if (output_name && strcmp(output_name, "-")) output = NULL; + if (output_name && output_fd) { + fprintf(stderr, "cannot use both --output and --log-fd\n"); + usage_with_options(stat_usage, options); + } if (!output) { struct timespec tm; mode = append_file ? "a" : "w"; @@ -1177,6 +1184,13 @@ int cmd_stat(int argc, const char **argv, const char *prefix __used) } clock_gettime(CLOCK_REALTIME, &tm); fprintf(output, "# started on %s\n", ctime(&tm.tv_sec)); + } else if (output_fd != 2) { + mode = append_file ? "a" : "w"; + output = fdopen(output_fd, mode); + if (!output) { + perror("Failed opening logfd"); + return -errno; + } } if (csv_sep) -- 2.20.1