[PATCH 03/16] perf probe: Remove caches when --cache is given

From: Arnaldo Carvalho de Melo
Date: Mon Jul 04 2016 - 20:39:13 EST


From: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>

'perf probe --del' removes caches when '--cache' is given. Note that
the delete pattern is not the same as for normal events.

If you cached probes with event name, --del "eventname" works as
expected. However, if you skipped it, the cached probes doesn't have
actual event name. In that case --del "probe-desc" is required (wildcard
is acceptable). For example a cache entry has the probe-desc "vfs_read
$params", you can remove it with --del 'vfs_read*'.

-----
# perf probe --cache --list
/[kernel.kallsyms] (1466a0a250b5d0070c6d0f03c5fed30b237970a1):
vfs_read $params
/usr/lib64/libc-2.17.so (c31ffe7942bfd77b2fca8f9bd5709d387a86d3bc):
getaddrinfo $params

# perf probe --cache --del vfs_read\*
Removed cached event: probe:vfs_read

# perf probe --cache --list
/[kernel.kallsyms] (1466a0a250b5d0070c6d0f03c5fed30b237970a1):
/usr/lib64/libc-2.17.so (c31ffe7942bfd77b2fca8f9bd5709d387a86d3bc):
getaddrinfo $params
-----

Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Ananth N Mavinakayanahalli <ananth@xxxxxxxxxxxxxxxxxx>
Cc: Brendan Gregg <brendan.d.gregg@xxxxxxxxx>
Cc: Hemant Kumar <hemant@xxxxxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: 146736021651.27797.10250879847070772920.stgit@devbox">http://lkml.kernel.org/r/146736021651.27797.10250879847070772920.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/Documentation/perf-probe.txt | 1 +
tools/perf/builtin-probe.c | 29 ++++++++++++++++++++++++++
tools/perf/util/probe-file.c | 36 +++++++++++++++++++++++++--------
tools/perf/util/probe-file.h | 2 ++
4 files changed, 60 insertions(+), 8 deletions(-)

diff --git a/tools/perf/Documentation/perf-probe.txt b/tools/perf/Documentation/perf-probe.txt
index 5a70d45015ea..8d091734d02c 100644
--- a/tools/perf/Documentation/perf-probe.txt
+++ b/tools/perf/Documentation/perf-probe.txt
@@ -116,6 +116,7 @@ OPTIONS
(With --add) Cache the probes. Any events which successfully added
are also stored in the cache file.
(With --list) Show cached probes.
+ (With --del) Remove cached probes.

--max-probes=NUM::
Set the maximum number of probe points for an event. Default is 128.
diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index 0bb9084bf6cf..a1a5cd1b8d60 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -363,6 +363,32 @@ out_cleanup:
return ret;
}

+static int del_perf_probe_caches(struct strfilter *filter)
+{
+ struct probe_cache *cache;
+ struct strlist *bidlist;
+ struct str_node *nd;
+ int ret;
+
+ bidlist = build_id_cache__list_all();
+ if (!bidlist) {
+ ret = -errno;
+ pr_debug("Failed to get buildids: %d\n", ret);
+ return ret ?: -ENOMEM;
+ }
+
+ strlist__for_each_entry(nd, bidlist) {
+ cache = probe_cache__new(nd->s);
+ if (!cache)
+ continue;
+ if (probe_cache__filter_purge(cache, filter) < 0 ||
+ probe_cache__commit(cache) < 0)
+ pr_warning("Failed to remove entries for %s\n", nd->s);
+ probe_cache__delete(cache);
+ }
+ return 0;
+}
+
static int perf_del_probe_events(struct strfilter *filter)
{
int ret, ret2, ufd = -1, kfd = -1;
@@ -375,6 +401,9 @@ static int perf_del_probe_events(struct strfilter *filter)

pr_debug("Delete filter: \'%s\'\n", str);

+ if (probe_conf.cache)
+ return del_perf_probe_caches(filter);
+
/* Get current event names */
ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW);
if (ret < 0)
diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index 156e3d883965..6cb6ec03c1fe 100644
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -684,20 +684,40 @@ out:
return ret;
}

+static bool probe_cache_entry__compare(struct probe_cache_entry *entry,
+ struct strfilter *filter)
+{
+ char buf[128], *ptr = entry->spev;
+
+ if (entry->pev.event) {
+ snprintf(buf, 128, "%s:%s", entry->pev.group, entry->pev.event);
+ ptr = buf;
+ }
+ return strfilter__compare(filter, ptr);
+}
+
+int probe_cache__filter_purge(struct probe_cache *pcache,
+ struct strfilter *filter)
+{
+ struct probe_cache_entry *entry, *tmp;
+
+ list_for_each_entry_safe(entry, tmp, &pcache->entries, node) {
+ if (probe_cache_entry__compare(entry, filter)) {
+ pr_info("Removed cached event: %s\n", entry->spev);
+ list_del_init(&entry->node);
+ probe_cache_entry__delete(entry);
+ }
+ }
+ return 0;
+}
+
static int probe_cache__show_entries(struct probe_cache *pcache,
struct strfilter *filter)
{
struct probe_cache_entry *entry;
- char buf[128], *ptr;

list_for_each_entry(entry, &pcache->entries, node) {
- if (entry->pev.event) {
- ptr = buf;
- snprintf(buf, 128, "%s:%s",
- entry->pev.group, entry->pev.event);
- } else
- ptr = entry->spev;
- if (strfilter__compare(filter, ptr))
+ if (probe_cache_entry__compare(entry, filter))
printf("%s\n", entry->spev);
}
return 0;
diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h
index 0009b8a65a5c..0ed1fc563b77 100644
--- a/tools/perf/util/probe-file.h
+++ b/tools/perf/util/probe-file.h
@@ -38,6 +38,8 @@ int probe_cache__add_entry(struct probe_cache *pcache,
int probe_cache__commit(struct probe_cache *pcache);
void probe_cache__purge(struct probe_cache *pcache);
void probe_cache__delete(struct probe_cache *pcache);
+int probe_cache__filter_purge(struct probe_cache *pcache,
+ struct strfilter *filter);
struct probe_cache_entry *probe_cache__find(struct probe_cache *pcache,
struct perf_probe_event *pev);
struct probe_cache_entry *probe_cache__find_by_name(struct probe_cache *pcache,
--
2.7.4