[PATCH perf/core v11 10/20] perf probe: Remove caches when --cache is given

Masami Hiramatsu
2016-06-15T03:29:23Z

From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>

perf-probe --del removes caches when --cache is given.
Note that the delete pattern is not same as 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 <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
Changes in v11:
- Fix to check the result of purging cache entries.
- Rename probe_cache__remove_entries to probe_cache__filter_purge.
Changes in v9:
- Fix to show which event is deleted (Thanks Hemant!)
Changes in v4:
- move del_perf_probe_caches() into builtin-probe.c since
command-line related delete procedure is there now.
---
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 5a70d45..8d09173 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 53e380c0e..6c2c0d1 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(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 47e0e95..f8f710e 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 0009b8a..0ed1fc5 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,