diff options
author | Jason Baron <jbaron@redhat.com> | 2009-07-21 20:16:29 +0200 |
---|---|---|
committer | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2009-07-22 18:05:57 +0200 |
commit | 5beeded123c5befa21f1c6e16219f2a3eb7dd197 (patch) | |
tree | 4ac812126910994516300c53171c7267b97f6f5d /tools/perf/perf.c | |
parent | perf_counter: Add tracepoint support to perf list, perf stat (diff) | |
download | linux-5beeded123c5befa21f1c6e16219f2a3eb7dd197.tar.xz linux-5beeded123c5befa21f1c6e16219f2a3eb7dd197.zip |
perf_counter: Detect debugfs location
If "/sys/kernel/debug" is not a debugfs mount point, search for the debugfs
filesystem in /proc/mounts, but also allows the user to specify
'--debugfs-dir=blah' or set the environment variable: 'PERF_DEBUGFS_DIR'
Signed-off-by: Jason Baron <jbaron@redhat.com>
[ also made it probe "/debug" by default ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090721181629.GA3094@redhat.com>
Diffstat (limited to 'tools/perf/perf.c')
-rw-r--r-- | tools/perf/perf.c | 77 |
1 files changed, 76 insertions, 1 deletions
diff --git a/tools/perf/perf.c b/tools/perf/perf.c index c5656784c61d..31982ad064b4 100644 --- a/tools/perf/perf.c +++ b/tools/perf/perf.c @@ -12,6 +12,8 @@ #include "util/cache.h" #include "util/quote.h" #include "util/run-command.h" +#include "util/parse-events.h" +#include "util/string.h" const char perf_usage_string[] = "perf [--version] [--help] COMMAND [ARGS]"; @@ -25,6 +27,8 @@ struct pager_config { int val; }; +static char debugfs_mntpt[MAXPATHLEN]; + static int pager_command_config(const char *var, const char *value, void *data) { struct pager_config *c = data; @@ -56,6 +60,15 @@ static void commit_pager_choice(void) { } } +static void set_debugfs_path(void) +{ + char *path; + + path = getenv(PERF_DEBUGFS_ENVIRONMENT); + snprintf(debugfs_path, MAXPATHLEN, "%s/%s", path ?: debugfs_mntpt, + "tracing/events"); +} + static int handle_options(const char*** argv, int* argc, int* envchanged) { int handled = 0; @@ -122,6 +135,22 @@ static int handle_options(const char*** argv, int* argc, int* envchanged) setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + 12, 1); if (envchanged) *envchanged = 1; + } else if (!strcmp(cmd, "--debugfs-dir")) { + if (*argc < 2) { + fprintf(stderr, "No directory given for --debugfs-dir.\n"); + usage(perf_usage_string); + } + strncpy(debugfs_mntpt, (*argv)[1], MAXPATHLEN); + debugfs_mntpt[MAXPATHLEN - 1] = '\0'; + if (envchanged) + *envchanged = 1; + (*argv)++; + (*argc)--; + } else if (!prefixcmp(cmd, "--debugfs-dir=")) { + strncpy(debugfs_mntpt, cmd + 14, MAXPATHLEN); + debugfs_mntpt[MAXPATHLEN - 1] = '\0'; + if (envchanged) + *envchanged = 1; } else { fprintf(stderr, "Unknown option: %s\n", cmd); usage(perf_usage_string); @@ -228,6 +257,7 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv) if (use_pager == -1 && p->option & USE_PAGER) use_pager = 1; commit_pager_choice(); + set_debugfs_path(); status = p->fn(argc, argv, prefix); if (status) @@ -346,6 +376,49 @@ static int run_argv(int *argcp, const char ***argv) return done_alias; } +/* mini /proc/mounts parser: searching for "^blah /mount/point debugfs" */ +static void get_debugfs_mntpt(void) +{ + FILE *file; + char fs_type[100]; + char debugfs[MAXPATHLEN]; + + /* + * try the standard location + */ + if (valid_debugfs_mount("/sys/kernel/debug/") == 0) { + strcpy(debugfs_mntpt, "/sys/kernel/debug/"); + return; + } + + /* + * try the sane location + */ + if (valid_debugfs_mount("/debug/") == 0) { + strcpy(debugfs_mntpt, "/debug/"); + return; + } + + /* + * give up and parse /proc/mounts + */ + file = fopen("/proc/mounts", "r"); + if (file == NULL) + return; + + while (fscanf(file, "%*s %" + STR(MAXPATHLEN) + "s %99s %*s %*d %*d\n", + debugfs, fs_type) == 2) { + if (strcmp(fs_type, "debugfs") == 0) + break; + } + fclose(file); + if (strcmp(fs_type, "debugfs") == 0) { + strncpy(debugfs_mntpt, debugfs, MAXPATHLEN); + debugfs_mntpt[MAXPATHLEN - 1] = '\0'; + } +} int main(int argc, const char **argv) { @@ -354,7 +427,8 @@ int main(int argc, const char **argv) cmd = perf_extract_argv0_path(argv[0]); if (!cmd) cmd = "perf-help"; - + /* get debugfs mount point from /proc/mounts */ + get_debugfs_mntpt(); /* * "perf-xxxx" is the same as "perf xxxx", but we obviously: * @@ -377,6 +451,7 @@ int main(int argc, const char **argv) argc--; handle_options(&argv, &argc, NULL); commit_pager_choice(); + set_debugfs_path(); if (argc > 0) { if (!prefixcmp(argv[0], "--")) argv[0] += 2; |