From e25613683bd5c46d3e8c8ae6416dccc9f357dcdc Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Sat, 21 Nov 2009 14:31:26 -0200 Subject: [PATCH] perf trace: Read_tracing_data should die() another day MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit It better propagate errors, also if we do a simple: [root@doppio linux-2.6-tip]# perf record -R -a -f sleep 3s ; perf trace [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.182 MB perf.data (~7972 samples) ] Fatal: not an trace data file [root@doppio linux-2.6-tip]# That is what is expected, right? I.e. as we didn't specify any tracepoint event via -e, it should gracefully bail out and not SEGFAULT. Signed-off-by: Arnaldo Carvalho de Melo Cc: Steven Rostedt Cc: Frédéric Weisbecker Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Paul Mackerras LKML-Reference: <1258821086-11521-3-git-send-email-acme@infradead.org> [ Fixed the error messages some more ] Signed-off-by: Ingo Molnar --- tools/perf/util/trace-event-info.c | 22 +++++++++++++++------- tools/perf/util/trace-event-read.c | 4 ++-- tools/perf/util/trace-event.h | 2 +- 3 files changed, 18 insertions(+), 10 deletions(-) diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c index 831052d4b4fb..cace35595530 100644 --- a/tools/perf/util/trace-event-info.c +++ b/tools/perf/util/trace-event-info.c @@ -33,11 +33,11 @@ #include #include #include +#include #include "../perf.h" #include "trace-event.h" - #define VERSION "0.5" #define _STR(x) #x @@ -483,23 +483,31 @@ static struct tracepoint_path * get_tracepoints_path(struct perf_event_attr *pattrs, int nb_events) { struct tracepoint_path path, *ppath = &path; - int i; + int i, nr_tracepoints = 0; for (i = 0; i < nb_events; i++) { if (pattrs[i].type != PERF_TYPE_TRACEPOINT) continue; + ++nr_tracepoints; ppath->next = tracepoint_id_to_path(pattrs[i].config); if (!ppath->next) die("%s\n", "No memory to alloc tracepoints list"); ppath = ppath->next; } - return path.next; + return nr_tracepoints > 0 ? path.next : NULL; } -void read_tracing_data(int fd, struct perf_event_attr *pattrs, int nb_events) + +int read_tracing_data(int fd, struct perf_event_attr *pattrs, int nb_events) { char buf[BUFSIZ]; - struct tracepoint_path *tps; + struct tracepoint_path *tps = get_tracepoints_path(pattrs, nb_events); + + /* + * What? No tracepoints? No sense writing anything here, bail out. + */ + if (tps == NULL) + return -1; output_fd = fd; @@ -528,11 +536,11 @@ void read_tracing_data(int fd, struct perf_event_attr *pattrs, int nb_events) page_size = getpagesize(); write_or_die(&page_size, 4); - tps = get_tracepoints_path(pattrs, nb_events); - read_header_files(); read_ftrace_files(tps); read_event_files(tps); read_proc_kallsyms(); read_ftrace_printk(); + + return 0; } diff --git a/tools/perf/util/trace-event-read.c b/tools/perf/util/trace-event-read.c index 44292e06cca4..342dfdd43f87 100644 --- a/tools/perf/util/trace-event-read.c +++ b/tools/perf/util/trace-event-read.c @@ -471,11 +471,11 @@ void trace_report(int fd) read_or_die(buf, 3); if (memcmp(buf, test, 3) != 0) - die("not an trace data file"); + die("no trace data in the file"); read_or_die(buf, 7); if (memcmp(buf, "tracing", 7) != 0) - die("not a trace file (missing tracing)"); + die("not a trace file (missing 'tracing' tag)"); version = read_string(); if (show_version) diff --git a/tools/perf/util/trace-event.h b/tools/perf/util/trace-event.h index f6637c2fa1fe..dd51c6872a15 100644 --- a/tools/perf/util/trace-event.h +++ b/tools/perf/util/trace-event.h @@ -248,7 +248,7 @@ unsigned long long raw_field_value(struct event *event, const char *name, void *data); void *raw_field_ptr(struct event *event, const char *name, void *data); -void read_tracing_data(int fd, struct perf_event_attr *pattrs, int nb_events); +int read_tracing_data(int fd, struct perf_event_attr *pattrs, int nb_events); /* taken from kernel/trace/trace.h */ enum trace_flag_type { -- 2.30.2