[tip:perf/core] perf tools: Simplify debugfs mountpoint handling code
From: tip-bot for Arnaldo Carvalho de Melo
Date: Mon Dec 05 2011 - 07:45:46 EST
Commit-ID: ebf294bf4f147aff29df5a16bfb0f8ebca15feaa
Gitweb: http://git.kernel.org/tip/ebf294bf4f147aff29df5a16bfb0f8ebca15feaa
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Wed, 16 Nov 2011 14:03:07 -0200
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Mon, 28 Nov 2011 10:11:28 -0200
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 <dsahern@xxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Link: http://lkml.kernel.org/n/tip-ug9jvtjrsqbluuhqqxpvg30f@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
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 831d1ba..77d68bf 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 73d0cac..2b2e225 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 680be34..ffc35e7 100644
--- a/tools/perf/util/debugfs.c
+++ b/tools/perf/util/debugfs.c
@@ -2,10 +2,12 @@
#include "debugfs.h"
#include "cache.h"
+#include <linux/kernel.h>
#include <sys/mount.h>
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 8cd3fa0..4a878f7 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 928918b..586ab3f 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 2f8e375..7e0cbe7 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 */
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