From f4d7da499e4fc1fdff8f26fdeb1a058d475a7a6c Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 16 Mar 2010 18:06:05 -0400 Subject: [PATCH] perf probe: Add --dry-run option Add --dry-run option for debugging and testing. Signed-off-by: Masami Hiramatsu Cc: systemtap Cc: DLE Cc: Frederic Weisbecker Cc: Arnaldo Carvalho de Melo Cc: Paul Mackerras Cc: Mike Galbraith Cc: Peter Zijlstra LKML-Reference: <20100316220605.32050.6571.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar --- tools/perf/Documentation/perf-probe.txt | 5 +++++ tools/perf/builtin-probe.c | 1 + tools/perf/util/probe-event.c | 24 ++++++++++++++++-------- tools/perf/util/probe-event.h | 2 ++ 4 files changed, 24 insertions(+), 8 deletions(-) diff --git a/tools/perf/Documentation/perf-probe.txt b/tools/perf/Documentation/perf-probe.txt index 34202b1be0bb..0f944b3be9e9 100644 --- a/tools/perf/Documentation/perf-probe.txt +++ b/tools/perf/Documentation/perf-probe.txt @@ -57,6 +57,11 @@ OPTIONS --force:: Forcibly add events with existing name. +-n:: +--dry-run:: + Dry run. With this option, --add and --del doesn't execute actual + adding and removal operations. + PROBE SYNTAX ------------ Probe points are defined by following syntax. diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c index f577e1410362..a1a2891ca66f 100644 --- a/tools/perf/builtin-probe.c +++ b/tools/perf/builtin-probe.c @@ -175,6 +175,7 @@ static const struct option options[] = { "FUNC[:RLN[+NUM|:RLN2]]|SRC:ALN[+NUM|:ALN2]", "Show source code lines.", opt_show_lines), #endif + OPT__DRY_RUN(&probe_event_dry_run), OPT_END() }; diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 1e60a659578b..ac41578a3552 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -49,6 +49,8 @@ #define MAX_PROBE_ARGS 128 #define PERFPROBE_GROUP "probe" +bool probe_event_dry_run; /* Dry run flag */ + #define semantic_error(msg ...) die("Semantic error :" msg) /* If there is no space to write, returns -E2BIG. */ @@ -430,7 +432,7 @@ int synthesize_trace_kprobe_event(struct probe_point *pp) return ret; } -static int open_kprobe_events(int flags, int mode) +static int open_kprobe_events(bool readwrite) { char buf[PATH_MAX]; int ret; @@ -439,7 +441,11 @@ static int open_kprobe_events(int flags, int mode) if (ret < 0) die("Failed to make kprobe_events path."); - ret = open(buf, flags, mode); + if (readwrite && !probe_event_dry_run) + ret = open(buf, O_RDWR, O_APPEND); + else + ret = open(buf, O_RDONLY, 0); + if (ret < 0) { if (errno == ENOENT) die("kprobe_events file does not exist -" @@ -535,7 +541,7 @@ void show_perf_probe_events(void) setup_pager(); memset(&pp, 0, sizeof(pp)); - fd = open_kprobe_events(O_RDONLY, 0); + fd = open_kprobe_events(false); rawlist = get_trace_kprobe_event_rawlist(fd); close(fd); @@ -585,9 +591,11 @@ static void write_trace_kprobe_event(int fd, const char *buf) int ret; pr_debug("Writing event: %s\n", buf); - ret = write(fd, buf, strlen(buf)); - if (ret <= 0) - die("Failed to write event: %s", strerror(errno)); + if (!probe_event_dry_run) { + ret = write(fd, buf, strlen(buf)); + if (ret <= 0) + die("Failed to write event: %s", strerror(errno)); + } } static void get_new_event_name(char *buf, size_t len, const char *base, @@ -630,7 +638,7 @@ static void __add_trace_kprobe_events(struct probe_point *probes, struct strlist *namelist; bool allow_suffix; - fd = open_kprobe_events(O_RDWR, O_APPEND); + fd = open_kprobe_events(true); /* Get current event names */ namelist = get_perf_event_names(fd, false); @@ -814,7 +822,7 @@ void del_trace_kprobe_events(struct strlist *dellist) struct str_node *ent; struct strlist *namelist; - fd = open_kprobe_events(O_RDWR, O_APPEND); + fd = open_kprobe_events(true); /* Get current event names */ namelist = get_perf_event_names(fd, true); diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h index 3865e163bb59..703b8876dfb1 100644 --- a/tools/perf/util/probe-event.h +++ b/tools/perf/util/probe-event.h @@ -5,6 +5,8 @@ #include "probe-finder.h" #include "strlist.h" +extern bool probe_event_dry_run; + extern void parse_line_range_desc(const char *arg, struct line_range *lr); extern void parse_perf_probe_event(const char *str, struct probe_point *pp, bool *need_dwarf);