From 592d5a6ba86a31681fa5e20a63a145b0a3b53c8a Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 2 Sep 2015 09:56:34 +0200 Subject: tools lib api fs: Move tracing_path interface into api/fs/tracing_path.c Moving tracing_path interface into api/fs/tracing_path.c out of util.c. It seems generic enough to be used by others, and I couldn't think of better place. Signed-off-by: Jiri Olsa Reviewed-by: Matt Fleming Reviewed-by: Raphael Beamonte Cc: David Ahern Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Steven Rostedt Link: http://lkml.kernel.org/r/1441180605-24737-5-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/api/fs/tracing_path.c | 83 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 83 insertions(+) create mode 100644 tools/lib/api/fs/tracing_path.c (limited to 'tools/lib/api/fs/tracing_path.c') diff --git a/tools/lib/api/fs/tracing_path.c b/tools/lib/api/fs/tracing_path.c new file mode 100644 index 000000000000..1fd6e1f99234 --- /dev/null +++ b/tools/lib/api/fs/tracing_path.c @@ -0,0 +1,83 @@ +#ifndef _GNU_SOURCE +# define _GNU_SOURCE +#endif + +#include +#include +#include +#include "debugfs.h" +#include "tracefs.h" + +#include "tracing_path.h" + + +char tracing_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing"; +char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events"; + + +static void __tracing_path_set(const char *tracing, const char *mountpoint) +{ + snprintf(tracing_path, sizeof(tracing_path), "%s/%s", + mountpoint, tracing); + snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s%s", + mountpoint, tracing, "events"); +} + +static const char *tracing_path_tracefs_mount(void) +{ + const char *mnt; + + mnt = tracefs_mount(NULL); + if (!mnt) + return NULL; + + __tracing_path_set("", mnt); + + return mnt; +} + +static const char *tracing_path_debugfs_mount(void) +{ + const char *mnt; + + mnt = debugfs_mount(NULL); + if (!mnt) + return NULL; + + __tracing_path_set("tracing/", mnt); + + return mnt; +} + +const char *tracing_path_mount(void) +{ + const char *mnt; + + mnt = tracing_path_tracefs_mount(); + if (mnt) + return mnt; + + mnt = tracing_path_debugfs_mount(); + + return mnt; +} + +void tracing_path_set(const char *mntpt) +{ + __tracing_path_set("tracing/", mntpt); +} + +char *get_tracing_file(const char *name) +{ + char *file; + + if (asprintf(&file, "%s/%s", tracing_path, name) < 0) + return NULL; + + return file; +} + +void put_tracing_file(char *file) +{ + free(file); +} -- cgit From 988bdb319246dea977a375beee39a5452e99b3ef Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 2 Sep 2015 09:56:35 +0200 Subject: tools lib api fs: Move debugfs__strerror_open into tracing_path.c object Moving debugfs__strerror_open out of api/fs/debugfs.c, because it's not debugfs specific. It'll be changed to consider tracefs mount as well in following patches. Renaming it into tracing_path__strerror_open_tp to fit into the namespace. No functional change is intended. Signed-off-by: Jiri Olsa Reviewed-by: Matt Fleming Cc: Raphael Beamonte Cc: David Ahern Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Steven Rostedt Link: http://lkml.kernel.org/r/1441180605-24737-6-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/api/fs/tracing_path.c | 54 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) (limited to 'tools/lib/api/fs/tracing_path.c') diff --git a/tools/lib/api/fs/tracing_path.c b/tools/lib/api/fs/tracing_path.c index 1fd6e1f99234..3b3e4f5fc50b 100644 --- a/tools/lib/api/fs/tracing_path.c +++ b/tools/lib/api/fs/tracing_path.c @@ -5,6 +5,8 @@ #include #include #include +#include +#include #include "debugfs.h" #include "tracefs.h" @@ -81,3 +83,55 @@ void put_tracing_file(char *file) { free(file); } + +static int strerror_open(int err, char *buf, size_t size, const char *filename) +{ + char sbuf[128]; + + switch (err) { + case ENOENT: + if (debugfs_configured()) { + snprintf(buf, size, + "Error:\tFile %s/%s not found.\n" + "Hint:\tPerhaps this kernel misses some CONFIG_ setting to enable this feature?.\n", + debugfs_mountpoint, filename); + break; + } + snprintf(buf, size, "%s", + "Error:\tUnable to find debugfs\n" + "Hint:\tWas your kernel compiled with debugfs support?\n" + "Hint:\tIs the debugfs filesystem mounted?\n" + "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'"); + break; + case EACCES: { + const char *mountpoint = debugfs_mountpoint; + + if (!access(debugfs_mountpoint, R_OK) && strncmp(filename, "tracing/", 8) == 0) { + const char *tracefs_mntpoint = tracefs_find_mountpoint(); + + if (tracefs_mntpoint) + mountpoint = tracefs_mntpoint; + } + + snprintf(buf, size, + "Error:\tNo permissions to read %s/%s\n" + "Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n", + debugfs_mountpoint, filename, mountpoint); + } + break; + default: + snprintf(buf, size, "%s", strerror_r(err, sbuf, sizeof(sbuf))); + break; + } + + return 0; +} + +int tracing_path__strerror_open_tp(int err, char *buf, size_t size, const char *sys, const char *name) +{ + char path[PATH_MAX]; + + snprintf(path, PATH_MAX, "tracing/events/%s/%s", sys, name ?: "*"); + + return strerror_open(err, buf, size, path); +} -- cgit From 4f234f06d608635a1cff936131285a91af213b37 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 2 Sep 2015 09:56:36 +0200 Subject: tools lib api fs: Make tracing_path_strerror_open message generic Making tracing_path__strerror_open_tp message generic by mentioning both debugfs/tracefs words in error message plus the tracing_path instead of debugfs_mountpoint. Signed-off-by: Jiri Olsa Cc: David Ahern Cc: Matt Fleming Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Raphael Beamonte Cc: Steven Rostedt Link: http://lkml.kernel.org/r/1441180605-24737-7-git-send-email-jolsa@kernel.org [ Add comment for the ENOENT case out of this patch discussion thread ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/api/fs/tracing_path.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) (limited to 'tools/lib/api/fs/tracing_path.c') diff --git a/tools/lib/api/fs/tracing_path.c b/tools/lib/api/fs/tracing_path.c index 3b3e4f5fc50b..1e0bb0da5e4f 100644 --- a/tools/lib/api/fs/tracing_path.c +++ b/tools/lib/api/fs/tracing_path.c @@ -90,33 +90,39 @@ static int strerror_open(int err, char *buf, size_t size, const char *filename) switch (err) { case ENOENT: - if (debugfs_configured()) { + /* + * We will get here if we can't find the tracepoint, but one of + * debugfs or tracefs is configured, which means you probably + * want some tracepoint which wasn't compiled in your kernel. + * - jirka + */ + if (debugfs_configured() || tracefs_configured()) { snprintf(buf, size, "Error:\tFile %s/%s not found.\n" "Hint:\tPerhaps this kernel misses some CONFIG_ setting to enable this feature?.\n", - debugfs_mountpoint, filename); + tracing_events_path, filename); break; } snprintf(buf, size, "%s", - "Error:\tUnable to find debugfs\n" - "Hint:\tWas your kernel compiled with debugfs support?\n" - "Hint:\tIs the debugfs filesystem mounted?\n" + "Error:\tUnable to find debugfs/tracefs\n" + "Hint:\tWas your kernel compiled with debugfs/tracefs support?\n" + "Hint:\tIs the debugfs/tracefs filesystem mounted?\n" "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'"); break; case EACCES: { - const char *mountpoint = debugfs_mountpoint; + const char *mountpoint = debugfs_find_mountpoint(); - if (!access(debugfs_mountpoint, R_OK) && strncmp(filename, "tracing/", 8) == 0) { + if (!access(mountpoint, R_OK) && strncmp(filename, "tracing/", 8) == 0) { const char *tracefs_mntpoint = tracefs_find_mountpoint(); if (tracefs_mntpoint) - mountpoint = tracefs_mntpoint; + mountpoint = tracefs_find_mountpoint(); } snprintf(buf, size, "Error:\tNo permissions to read %s/%s\n" "Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n", - debugfs_mountpoint, filename, mountpoint); + tracing_events_path, filename, mountpoint); } break; default: @@ -131,7 +137,7 @@ int tracing_path__strerror_open_tp(int err, char *buf, size_t size, const char * { char path[PATH_MAX]; - snprintf(path, PATH_MAX, "tracing/events/%s/%s", sys, name ?: "*"); + snprintf(path, PATH_MAX, "%s/%s", sys, name ?: "*"); return strerror_open(err, buf, size, path); } -- cgit From 4605eab3487dc818b1f3cbee2cd139cca3564be7 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 2 Sep 2015 09:56:43 +0200 Subject: tools lib api fs: Replace debugfs/tracefs objects interface with fs.c Switching to the fs.c related filesystem framework. Signed-off-by: Jiri Olsa Cc: David Ahern Cc: Matt Fleming Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Raphael Beamonte Cc: Steven Rostedt Link: http://lkml.kernel.org/r/1441180605-24737-14-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/api/fs/tracing_path.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) (limited to 'tools/lib/api/fs/tracing_path.c') diff --git a/tools/lib/api/fs/tracing_path.c b/tools/lib/api/fs/tracing_path.c index 1e0bb0da5e4f..38aca2dd1946 100644 --- a/tools/lib/api/fs/tracing_path.c +++ b/tools/lib/api/fs/tracing_path.c @@ -7,8 +7,7 @@ #include #include #include -#include "debugfs.h" -#include "tracefs.h" +#include "fs.h" #include "tracing_path.h" @@ -29,7 +28,7 @@ static const char *tracing_path_tracefs_mount(void) { const char *mnt; - mnt = tracefs_mount(NULL); + mnt = tracefs__mount(); if (!mnt) return NULL; @@ -42,7 +41,7 @@ static const char *tracing_path_debugfs_mount(void) { const char *mnt; - mnt = debugfs_mount(NULL); + mnt = debugfs__mount(); if (!mnt) return NULL; @@ -96,7 +95,7 @@ static int strerror_open(int err, char *buf, size_t size, const char *filename) * want some tracepoint which wasn't compiled in your kernel. * - jirka */ - if (debugfs_configured() || tracefs_configured()) { + if (debugfs__configured() || tracefs__configured()) { snprintf(buf, size, "Error:\tFile %s/%s not found.\n" "Hint:\tPerhaps this kernel misses some CONFIG_ setting to enable this feature?.\n", @@ -110,13 +109,13 @@ static int strerror_open(int err, char *buf, size_t size, const char *filename) "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'"); break; case EACCES: { - const char *mountpoint = debugfs_find_mountpoint(); + const char *mountpoint = debugfs__mountpoint(); if (!access(mountpoint, R_OK) && strncmp(filename, "tracing/", 8) == 0) { - const char *tracefs_mntpoint = tracefs_find_mountpoint(); + const char *tracefs_mntpoint = tracefs__mountpoint(); if (tracefs_mntpoint) - mountpoint = tracefs_find_mountpoint(); + mountpoint = tracefs__mountpoint(); } snprintf(buf, size, -- cgit From dc240c5dc2a02e335c5bcb50ad3a1274818c8609 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Sat, 19 Sep 2015 16:47:07 +0200 Subject: tools lib api fs: Store tracing mountpoint for better error message Storing the actual tracing path mountpoint to display correct error message hint ('Hint:' line). The error hint rediscovers mountpoints, but it could be different from what we actually used in tracing path. Before we'd display debugfs mount even though tracefs was used: $ perf record -e sched:sched_krava ls event syntax error: 'sched:sched_krava' \___ can't access trace events Error: No permissions to read /sys/kernel/debug/tracing/events/sched/sched_krava Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug' ... After this change, correct mountpoint is displayed: $ perf record -e sched:sched_krava ls event syntax error: 'sched:sched_krava' \___ can't access trace events Error: No permissions to read /sys/kernel/debug/tracing/events/sched/sched_krava Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug/tracing' ... Signed-off-by: Jiri Olsa Cc: David Ahern Cc: Matt Fleming Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Raphael Beamonte Link: http://lkml.kernel.org/r/1442674027-19427-1-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/api/fs/tracing_path.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) (limited to 'tools/lib/api/fs/tracing_path.c') diff --git a/tools/lib/api/fs/tracing_path.c b/tools/lib/api/fs/tracing_path.c index 38aca2dd1946..0406a7d5c891 100644 --- a/tools/lib/api/fs/tracing_path.c +++ b/tools/lib/api/fs/tracing_path.c @@ -12,12 +12,14 @@ #include "tracing_path.h" +char tracing_mnt[PATH_MAX + 1] = "/sys/kernel/debug"; char tracing_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing"; char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events"; static void __tracing_path_set(const char *tracing, const char *mountpoint) { + snprintf(tracing_mnt, sizeof(tracing_mnt), "%s", mountpoint); snprintf(tracing_path, sizeof(tracing_path), "%s/%s", mountpoint, tracing); snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s%s", @@ -109,19 +111,10 @@ static int strerror_open(int err, char *buf, size_t size, const char *filename) "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'"); break; case EACCES: { - const char *mountpoint = debugfs__mountpoint(); - - if (!access(mountpoint, R_OK) && strncmp(filename, "tracing/", 8) == 0) { - const char *tracefs_mntpoint = tracefs__mountpoint(); - - if (tracefs_mntpoint) - mountpoint = tracefs__mountpoint(); - } - snprintf(buf, size, "Error:\tNo permissions to read %s/%s\n" "Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n", - tracing_events_path, filename, mountpoint); + tracing_events_path, filename, tracing_mnt); } break; default: -- cgit From ccb5597f9ba11b67b8aa8c6f4682675eceee0e21 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Mon, 5 Oct 2015 20:06:01 +0200 Subject: tools lib api fs: No need to use PATH_MAX + 1 Because there's no point, PATH_MAX is big enough. Signed-off-by: Jiri Olsa Cc: David Ahern Cc: Don Zickus Cc: Kan Liang Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1444068369-20978-2-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/api/fs/tracing_path.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'tools/lib/api/fs/tracing_path.c') diff --git a/tools/lib/api/fs/tracing_path.c b/tools/lib/api/fs/tracing_path.c index 0406a7d5c891..a26bb5ea8283 100644 --- a/tools/lib/api/fs/tracing_path.c +++ b/tools/lib/api/fs/tracing_path.c @@ -12,9 +12,9 @@ #include "tracing_path.h" -char tracing_mnt[PATH_MAX + 1] = "/sys/kernel/debug"; -char tracing_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing"; -char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events"; +char tracing_mnt[PATH_MAX] = "/sys/kernel/debug"; +char tracing_path[PATH_MAX] = "/sys/kernel/debug/tracing"; +char tracing_events_path[PATH_MAX] = "/sys/kernel/debug/tracing/events"; static void __tracing_path_set(const char *tracing, const char *mountpoint) -- cgit