perf probe: Use cache entry if possible

Before analyzing debuginfo, try to find a corresponding entry from probe
cache always. This does not depend on --cache, the --cache enables to
store/update cache, but looking up the cache is always enabled.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/146736019226.27797.16366402884098398857.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 55f41d5e20d1145d7d1a4abf41ba82ee9bfe3013..47b6b8b7206e276e652bab63885ba6989deb1793 100644 (file)
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2474,17 +2474,24 @@ static int probe_trace_event__set_name(struct probe_trace_event *tev,
        char buf[64];
        int ret;
 
+       /* If probe_event or trace_event already have the name, reuse it */
        if (pev->event)
                event = pev->event;
-       else
+       else if (tev->event)
+               event = tev->event;
+       else {
+               /* Or generate new one from probe point */
                if (pev->point.function &&
                        (strncmp(pev->point.function, "0x", 2) != 0) &&
                        !strisglob(pev->point.function))
                        event = pev->point.function;
                else
                        event = tev->point.realname;
+       }
        if (pev->group)
                group = pev->group;
+       else if (tev->group)
+               group = tev->group;
        else
                group = PERFPROBE_GROUP;
 
@@ -2531,7 +2538,7 @@ static int __add_probe_trace_events(struct perf_probe_event *pev,
        for (i = 0; i < ntevs; i++) {
                tev = &tevs[i];
                /* Skip if the symbol is out of .text or blacklisted */
-               if (!tev->point.symbol)
+               if (!tev->point.symbol && !pev->uprobes)
                        continue;
 
                /* Set new name for tev (and update namelist) */
@@ -2844,6 +2851,55 @@ errout:
 
 bool __weak arch__prefers_symtab(void) { return false; }
 
+static int find_probe_trace_events_from_cache(struct perf_probe_event *pev,
+                                             struct probe_trace_event **tevs)
+{
+       struct probe_cache *cache;
+       struct probe_cache_entry *entry;
+       struct probe_trace_event *tev;
+       struct str_node *node;
+       int ret, i;
+
+       cache = probe_cache__new(pev->target);
+       if (!cache)
+               return 0;
+
+       entry = probe_cache__find(cache, pev);
+       if (!entry) {
+               ret = 0;
+               goto out;
+       }
+
+       ret = strlist__nr_entries(entry->tevlist);
+       if (ret > probe_conf.max_probes) {
+               pr_debug("Too many entries matched in the cache of %s\n",
+                        pev->target ? : "kernel");
+               ret = -E2BIG;
+               goto out;
+       }
+
+       *tevs = zalloc(ret * sizeof(*tev));
+       if (!*tevs) {
+               ret = -ENOMEM;
+               goto out;
+       }
+
+       i = 0;
+       strlist__for_each_entry(node, entry->tevlist) {
+               tev = &(*tevs)[i++];
+               ret = parse_probe_trace_command(node->s, tev);
+               if (ret < 0)
+                       goto out;
+               /* Set the uprobes attribute as same as original */
+               tev->uprobes = pev->uprobes;
+       }
+       ret = i;
+
+out:
+       probe_cache__delete(cache);
+       return ret;
+}
+
 static int convert_to_probe_trace_events(struct perf_probe_event *pev,
                                         struct probe_trace_event **tevs)
 {
@@ -2866,6 +2922,11 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev,
        if (ret > 0)
                return ret;
 
+       /* At first, we need to lookup cache entry */
+       ret = find_probe_trace_events_from_cache(pev, tevs);
+       if (ret > 0)
+               return ret;     /* Found in probe cache */
+
        if (arch__prefers_symtab() && !perf_probe_event_need_dwarf(pev)) {
                ret = find_probe_trace_events_from_map(pev, tevs);
                if (ret > 0)

diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index 1c12c1ab19c94d61976dada1705d669fe2949fd4..a94ee478178d1ef53f852acc3cd7304ce60905ed 100644 (file)
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -524,7 +524,7 @@ static bool streql(const char *a, const char *b)
        return !strcmp(a, b);
 }
 
-static struct probe_cache_entry *
+struct probe_cache_entry *
 probe_cache__find(struct probe_cache *pcache, struct perf_probe_event *pev)
 {
        struct probe_cache_entry *entry = NULL;
@@ -548,6 +548,24 @@ found:
        return entry;
 }
 
+struct probe_cache_entry *
+probe_cache__find_by_name(struct probe_cache *pcache,
+                         const char *group, const char *event)
+{
+       struct probe_cache_entry *entry = NULL;
+
+       list_for_each_entry(entry, &pcache->entries, node) {
+               /* Hit if same event name or same command-string */
+               if (streql(entry->pev.group, group) &&
+                   streql(entry->pev.event, event))
+                       goto found;
+       }
+       entry = NULL;
+
+found:
+       return entry;
+}
+
 int probe_cache__add_entry(struct probe_cache *pcache,
                           struct perf_probe_event *pev,
                           struct probe_trace_event *tevs, int ntevs)

diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h
index d872e3df7e59166d00bb51eb696e5df38f8c032d..910aa74953e9c7a743b1d8200b7a16413513001c 100644 (file)
--- a/tools/perf/util/probe-file.h
+++ b/tools/perf/util/probe-file.h
@@ -38,5 +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);
-
+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,
+                                       const char *group, const char *event);
 #endif