From ebf294bf4f147aff29df5a16bfb0f8ebca15feaa Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 16 Nov 2011 14:03:07 -0200 Subject: [PATCH] perf tools: Simplify debugfs mountpoint handling code We don't need to have two PATH_MAX char sized arrays holding it, just one in util/debugfs.c will do. Also rename debugfs_path to tracing_events_path, as it is not the path to debugfs, that is debugfs_mountpoint. Both are now accessible. This will allow accessing this code in the perf python binding without having to drag in perf.c and util/parse-events.c. The defaults for these variables are the canonical "/sys/kernel/debug" and "/sys/kernel/debug/tracing/events/", removing the need for simple tools to call debugfs_mount(NULL). Cc: David Ahern Cc: Frederic Weisbecker Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-ug9jvtjrsqbluuhqqxpvg30f@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-test.c | 3 ++- tools/perf/perf.c | 33 ++++----------------------------- tools/perf/util/debugfs.c | 25 ++++++++++++++++++++----- tools/perf/util/debugfs.h | 4 ++++ tools/perf/util/parse-events.c | 28 +++++++++++++--------------- tools/perf/util/parse-events.h | 1 - 6 files changed, 43 insertions(+), 51 deletions(-) diff --git a/tools/perf/builtin-test.c b/tools/perf/builtin-test.c index 831d1baeac37..77d68bfb79da 100644 --- a/tools/perf/builtin-test.c +++ b/tools/perf/builtin-test.c @@ -7,6 +7,7 @@ #include "util/cache.h" #include "util/debug.h" +#include "util/debugfs.h" #include "util/evlist.h" #include "util/parse-options.h" #include "util/parse-events.h" @@ -247,7 +248,7 @@ static int trace_event__id(const char *evname) if (asprintf(&filename, "%s/syscalls/%s/id", - debugfs_path, evname) < 0) + tracing_events_path, evname) < 0) return -1; fd = open(filename, O_RDONLY); diff --git a/tools/perf/perf.c b/tools/perf/perf.c index 73d0cac8b67e..2b2e225a4d4c 100644 --- a/tools/perf/perf.c +++ b/tools/perf/perf.c @@ -29,8 +29,6 @@ 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; @@ -81,15 +79,6 @@ 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; @@ -161,15 +150,14 @@ static int handle_options(const char ***argv, int *argc, int *envchanged) fprintf(stderr, "No directory given for --debugfs-dir.\n"); usage(perf_usage_string); } - strncpy(debugfs_mntpt, (*argv)[1], MAXPATHLEN); - debugfs_mntpt[MAXPATHLEN - 1] = '\0'; + debugfs_set_path((*argv)[1]); if (envchanged) *envchanged = 1; (*argv)++; (*argc)--; } else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) { - strncpy(debugfs_mntpt, cmd + strlen(CMD_DEBUGFS_DIR), MAXPATHLEN); - debugfs_mntpt[MAXPATHLEN - 1] = '\0'; + debugfs_set_path(cmd + strlen(CMD_DEBUGFS_DIR)); + fprintf(stderr, "dir: %s\n", debugfs_mountpoint); if (envchanged) *envchanged = 1; } else { @@ -281,7 +269,6 @@ 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); exit_browser(status); @@ -416,17 +403,6 @@ 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) -{ - const char *path = debugfs_mount(NULL); - - if (path) - strncpy(debugfs_mntpt, path, sizeof(debugfs_mntpt)); - else - debugfs_mntpt[0] = '\0'; -} - static void pthread__block_sigwinch(void) { sigset_t set; @@ -453,7 +429,7 @@ int main(int argc, const char **argv) if (!cmd) cmd = "perf-help"; /* get debugfs mount point from /proc/mounts */ - get_debugfs_mntpt(); + debugfs_mount(NULL); /* * "perf-xxxx" is the same as "perf xxxx", but we obviously: * @@ -476,7 +452,6 @@ int main(int argc, const char **argv) argc--; handle_options(&argv, &argc, NULL); commit_pager_choice(); - set_debugfs_path(); set_buildid_dir(); if (argc > 0) { diff --git a/tools/perf/util/debugfs.c b/tools/perf/util/debugfs.c index 680be3460e86..ffc35e748e89 100644 --- a/tools/perf/util/debugfs.c +++ b/tools/perf/util/debugfs.c @@ -2,10 +2,12 @@ #include "debugfs.h" #include "cache.h" +#include #include static int debugfs_premounted; -static char debugfs_mountpoint[PATH_MAX + 1]; +char debugfs_mountpoint[PATH_MAX + 1] = "/sys/kernel/debug"; +char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events"; static const char *debugfs_known_mountpoints[] = { "/sys/kernel/debug/", @@ -64,7 +66,7 @@ const char *debugfs_find_mountpoint(void) /* give up and parse /proc/mounts */ fp = fopen("/proc/mounts", "r"); if (fp == NULL) - die("Can't open /proc/mounts for read"); + return NULL; while (fscanf(fp, "%*s %" STR(PATH_MAX) "s %99s %*s %*d %*d\n", debugfs_mountpoint, type) == 2) { @@ -106,6 +108,12 @@ int debugfs_valid_entry(const char *path) return 0; } +static void debugfs_set_tracing_events_path(const char *mountpoint) +{ + snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s", + mountpoint, "tracing/events"); +} + /* mount the debugfs somewhere if it's not mounted */ char *debugfs_mount(const char *mountpoint) @@ -113,7 +121,7 @@ char *debugfs_mount(const char *mountpoint) /* see if it's already mounted */ if (debugfs_find_mountpoint()) { debugfs_premounted = 1; - return debugfs_mountpoint; + goto out; } /* if not mounted and no argument */ @@ -129,12 +137,19 @@ char *debugfs_mount(const char *mountpoint) return NULL; /* save the mountpoint */ - strncpy(debugfs_mountpoint, mountpoint, sizeof(debugfs_mountpoint)); debugfs_found = 1; - + strncpy(debugfs_mountpoint, mountpoint, sizeof(debugfs_mountpoint)); +out: + debugfs_set_tracing_events_path(debugfs_mountpoint); return debugfs_mountpoint; } +void debugfs_set_path(const char *mountpoint) +{ + snprintf(debugfs_mountpoint, sizeof(debugfs_mountpoint), "%s", mountpoint); + debugfs_set_tracing_events_path(mountpoint); +} + /* umount the debugfs */ int debugfs_umount(void) diff --git a/tools/perf/util/debugfs.h b/tools/perf/util/debugfs.h index 8cd3fa0af880..4a878f735eb0 100644 --- a/tools/perf/util/debugfs.h +++ b/tools/perf/util/debugfs.h @@ -6,9 +6,13 @@ int debugfs_valid_mountpoint(const char *debugfs); int debugfs_valid_entry(const char *path); char *debugfs_mount(const char *mountpoint); int debugfs_umount(void); +void debugfs_set_path(const char *mountpoint); int debugfs_write(const char *entry, const char *value); int debugfs_read(const char *entry, char *buffer, size_t size); void debugfs_force_cleanup(void); int debugfs_make_path(const char *element, char *buffer, int size); +extern char debugfs_mountpoint[]; +extern char tracing_events_path[]; + #endif /* __DEBUGFS_H__ */ diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index 928918b796b2..586ab3fe60f8 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -25,8 +25,6 @@ enum event_result { EVT_HANDLED_ALL }; -char debugfs_path[MAXPATHLEN]; - #define CHW(x) .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_##x #define CSW(x) .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_##x @@ -140,7 +138,7 @@ static int tp_event_has_id(struct dirent *sys_dir, struct dirent *evt_dir) char evt_path[MAXPATHLEN]; int fd; - snprintf(evt_path, MAXPATHLEN, "%s/%s/%s/id", debugfs_path, + snprintf(evt_path, MAXPATHLEN, "%s/%s/%s/id", tracing_events_path, sys_dir->d_name, evt_dir->d_name); fd = open(evt_path, O_RDONLY); if (fd < 0) @@ -171,16 +169,16 @@ struct tracepoint_path *tracepoint_id_to_path(u64 config) char evt_path[MAXPATHLEN]; char dir_path[MAXPATHLEN]; - if (debugfs_valid_mountpoint(debugfs_path)) + if (debugfs_valid_mountpoint(tracing_events_path)) return NULL; - sys_dir = opendir(debugfs_path); + sys_dir = opendir(tracing_events_path); if (!sys_dir) return NULL; for_each_subsystem(sys_dir, sys_dirent, sys_next) { - snprintf(dir_path, MAXPATHLEN, "%s/%s", debugfs_path, + snprintf(dir_path, MAXPATHLEN, "%s/%s", tracing_events_path, sys_dirent.d_name); evt_dir = opendir(dir_path); if (!evt_dir) @@ -447,7 +445,7 @@ parse_single_tracepoint_event(char *sys_name, u64 id; int fd; - snprintf(evt_path, MAXPATHLEN, "%s/%s/%s/id", debugfs_path, + snprintf(evt_path, MAXPATHLEN, "%s/%s/%s/id", tracing_events_path, sys_name, evt_name); fd = open(evt_path, O_RDONLY); @@ -485,7 +483,7 @@ parse_multiple_tracepoint_event(struct perf_evlist *evlist, char *sys_name, struct dirent *evt_ent; DIR *evt_dir; - snprintf(evt_path, MAXPATHLEN, "%s/%s", debugfs_path, sys_name); + snprintf(evt_path, MAXPATHLEN, "%s/%s", tracing_events_path, sys_name); evt_dir = opendir(evt_path); if (!evt_dir) { @@ -528,7 +526,7 @@ parse_tracepoint_event(struct perf_evlist *evlist, const char **strp, char sys_name[MAX_EVENT_LENGTH]; unsigned int sys_length, evt_length; - if (debugfs_valid_mountpoint(debugfs_path)) + if (debugfs_valid_mountpoint(tracing_events_path)) return 0; evt_name = strchr(*strp, ':'); @@ -920,10 +918,10 @@ void print_tracepoint_events(const char *subsys_glob, const char *event_glob) char evt_path[MAXPATHLEN]; char dir_path[MAXPATHLEN]; - if (debugfs_valid_mountpoint(debugfs_path)) + if (debugfs_valid_mountpoint(tracing_events_path)) return; - sys_dir = opendir(debugfs_path); + sys_dir = opendir(tracing_events_path); if (!sys_dir) return; @@ -932,7 +930,7 @@ void print_tracepoint_events(const char *subsys_glob, const char *event_glob) !strglobmatch(sys_dirent.d_name, subsys_glob)) continue; - snprintf(dir_path, MAXPATHLEN, "%s/%s", debugfs_path, + snprintf(dir_path, MAXPATHLEN, "%s/%s", tracing_events_path, sys_dirent.d_name); evt_dir = opendir(dir_path); if (!evt_dir) @@ -964,16 +962,16 @@ int is_valid_tracepoint(const char *event_string) char evt_path[MAXPATHLEN]; char dir_path[MAXPATHLEN]; - if (debugfs_valid_mountpoint(debugfs_path)) + if (debugfs_valid_mountpoint(tracing_events_path)) return 0; - sys_dir = opendir(debugfs_path); + sys_dir = opendir(tracing_events_path); if (!sys_dir) return 0; for_each_subsystem(sys_dir, sys_dirent, sys_next) { - snprintf(dir_path, MAXPATHLEN, "%s/%s", debugfs_path, + snprintf(dir_path, MAXPATHLEN, "%s/%s", tracing_events_path, sys_dirent.d_name); evt_dir = opendir(dir_path); if (!evt_dir) diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h index 2f8e375e038d..7e0cbe75d5f1 100644 --- a/tools/perf/util/parse-events.h +++ b/tools/perf/util/parse-events.h @@ -39,7 +39,6 @@ void print_tracepoint_events(const char *subsys_glob, const char *event_glob); int print_hwcache_events(const char *event_glob); extern int is_valid_tracepoint(const char *event_string); -extern char debugfs_path[]; extern int valid_debugfs_mount(const char *debugfs); #endif /* __PERF_PARSE_EVENTS_H */