From 196581717d85f59365dc9303685cd5b1cdf106a3 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Mon, 7 Sep 2015 10:38:07 +0200 Subject: [PATCH] perf tools: Enhance parsing events tracepoint error output Enhancing parsing events tracepoint error output. Adding more verbose output when the tracepoint is not found or the tracing event path cannot be access. $ sudo perf record -e sched:sched_krava ls event syntax error: 'sched:sched_krava' \___ unknown tracepoint Error: File /sys/kernel/debug/tracing//tracing/events/sched/sched_krava not found. Hint: Perhaps this kernel misses some CONFIG_ setting to enable this feature?. Run 'perf list' for a list of valid events ... $ 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//tracing/events/sched/sched_krava Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug' Run 'perf list' for a list of valid events ... Signed-off-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Cc: Raphael Beamonte Cc: David Ahern Cc: Matt Fleming Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1441615087-13886-6-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/parse-events.c | 35 +++++++++++++++++++++++++++++++--- tools/perf/util/parse-events.y | 16 +++++++++------- 2 files changed, 41 insertions(+), 10 deletions(-) diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index c47831c47220aa..d3fb90be6216d3 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -387,6 +387,33 @@ int parse_events_add_cache(struct list_head *list, int *idx, return add_event(list, idx, &attr, name, NULL); } +static void tracepoint_error(struct parse_events_error *error, int err, + char *sys, char *name) +{ + char help[BUFSIZ]; + + /* + * We get error directly from syscall errno ( > 0), + * or from encoded pointer's error ( < 0). + */ + err = abs(err); + + switch (err) { + case EACCES: + error->str = strdup("can't access trace events"); + break; + case ENOENT: + error->str = strdup("unknown tracepoint"); + break; + default: + error->str = strdup("failed to add tracepoint"); + break; + } + + tracing_path__strerror_open_tp(err, help, sizeof(help), sys, name); + error->help = strdup(help); +} + static int add_tracepoint(struct list_head *list, int *idx, char *sys_name, char *evt_name, struct parse_events_error *error __maybe_unused) @@ -394,8 +421,10 @@ static int add_tracepoint(struct list_head *list, int *idx, struct perf_evsel *evsel; evsel = perf_evsel__newtp_idx(sys_name, evt_name, (*idx)++); - if (IS_ERR(evsel)) + if (IS_ERR(evsel)) { + tracepoint_error(error, PTR_ERR(evsel), sys_name, evt_name); return PTR_ERR(evsel); + } list_add_tail(&evsel->node, list); return 0; @@ -413,7 +442,7 @@ static int add_tracepoint_multi_event(struct list_head *list, int *idx, snprintf(evt_path, MAXPATHLEN, "%s/%s", tracing_events_path, sys_name); evt_dir = opendir(evt_path); if (!evt_dir) { - perror("Can't open event dir"); + tracepoint_error(error, errno, sys_name, evt_name); return -1; } @@ -453,7 +482,7 @@ static int add_tracepoint_multi_sys(struct list_head *list, int *idx, events_dir = opendir(tracing_events_path); if (!events_dir) { - perror("Can't open event dir"); + tracepoint_error(error, errno, sys_name, evt_name); return -1; } diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y index 54a3004a8192fc..8bcc4586845782 100644 --- a/tools/perf/util/parse-events.y +++ b/tools/perf/util/parse-events.y @@ -371,28 +371,30 @@ event_legacy_tracepoint: PE_NAME '-' PE_NAME ':' PE_NAME { struct parse_events_evlist *data = _data; + struct parse_events_error *error = data->error; struct list_head *list; char sys_name[128]; snprintf(&sys_name, 128, "%s-%s", $1, $3); ALLOC_LIST(list); - ABORT_ON(parse_events_add_tracepoint(list, &data->idx, &sys_name, $5, data->error)); + if (parse_events_add_tracepoint(list, &data->idx, &sys_name, $5, error)) { + if (error) + error->idx = @1.first_column; + return -1; + } $$ = list; } | PE_NAME ':' PE_NAME { struct parse_events_evlist *data = _data; + struct parse_events_error *error = data->error; struct list_head *list; ALLOC_LIST(list); - if (parse_events_add_tracepoint(list, &data->idx, $1, $3, data->error)) { - struct parse_events_error *error = data->error; - - if (error) { + if (parse_events_add_tracepoint(list, &data->idx, $1, $3, error)) { + if (error) error->idx = @1.first_column; - error->str = strdup("unknown tracepoint"); - } return -1; } $$ = list;