From 42bba263eb58800b6239a0cb35ac17fd29379277 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 12 Jul 2016 19:05:18 +0900 Subject: perf probe: Allow wildcard for cached events Allo glob wildcard for reusing cached/SDT events. E.g. # perf probe -x /usr/lib64/libc-2.20.so -a %sdt_libc:\* This example adds probes for all SDT in libc. Note that the SDTs must have been scanned by perf buildid-cache. Committer note: Using it to check what of those SDT probes would take place when doing a cargo run (rust): # trace --no-sys --event sdt_libc:* cargo run 0.000 sdt_libc:setjmp:(7f326b69c4d1)) 28.423 sdt_libc:setjmp:(7f4b0a5364d1)) 29.000 sdt_libc:setjmp:(7f4b0a5364d1)) 88.597 sdt_libc:setjmp:(7fc01fd414d1)) 89.220 sdt_libc:setjmp:(7fc01fd414d1)) 95.501 sdt_libc:setjmp:(7f326b69c4d1)) Running `target/debug/hello_world` 97.110 sdt_libc:setjmp:(7f95e09234d1)) Hello, world! # Signed-off-by: Masami Hiramatsu Tested-by: Arnaldo Carvalho de Melo Cc: Ananth N Mavinakayanahalli Cc: Brendan Gregg Cc: Hemant Kumar Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/146831791813.17065.17846564230840594888.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/probe-event.c | 107 ++++++++++++++++++++++++++++++++++++++++-- tools/perf/util/probe-file.c | 38 ++++++++++++--- tools/perf/util/probe-file.h | 3 ++ 3 files changed, 138 insertions(+), 10 deletions(-) (limited to 'tools/perf') diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 85f25d4..7b96e68 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -1204,7 +1204,7 @@ static int parse_perf_probe_event_name(char **arg, struct perf_probe_event *pev) ptr = strchr(*arg, ':'); if (ptr) { *ptr = '\0'; - if (!is_c_func_name(*arg)) + if (!pev->sdt && !is_c_func_name(*arg)) goto ng_name; pev->group = strdup(*arg); if (!pev->group) @@ -1212,7 +1212,7 @@ static int parse_perf_probe_event_name(char **arg, struct perf_probe_event *pev) *arg = ptr + 1; } else pev->group = NULL; - if (!is_c_func_name(*arg)) { + if (!pev->sdt && !is_c_func_name(*arg)) { ng_name: semantic_error("%s is bad for event name -it must " "follow C symbol-naming rule.\n", *arg); @@ -1644,6 +1644,7 @@ int parse_probe_trace_command(const char *cmd, struct probe_trace_event *tev) ret = -ENOMEM; goto out; } + tev->uprobes = (tp->module[0] == '/'); p++; } else p = argv[1]; @@ -2518,7 +2519,7 @@ static int probe_trace_event__set_name(struct probe_trace_event *tev, int ret; /* If probe_event or trace_event already have the name, reuse it */ - if (pev->event) + if (pev->event && !pev->sdt) event = pev->event; else if (tev->event) event = tev->event; @@ -2531,7 +2532,7 @@ static int probe_trace_event__set_name(struct probe_trace_event *tev, else event = tev->point.realname; } - if (pev->group) + if (pev->group && !pev->sdt) group = pev->group; else if (tev->group) group = tev->group; @@ -2894,6 +2895,100 @@ errout: bool __weak arch__prefers_symtab(void) { return false; } +/* Concatinate two arrays */ +static void *memcat(void *a, size_t sz_a, void *b, size_t sz_b) +{ + void *ret; + + ret = malloc(sz_a + sz_b); + if (ret) { + memcpy(ret, a, sz_a); + memcpy(ret + sz_a, b, sz_b); + } + return ret; +} + +static int +concat_probe_trace_events(struct probe_trace_event **tevs, int *ntevs, + struct probe_trace_event **tevs2, int ntevs2) +{ + struct probe_trace_event *new_tevs; + int ret = 0; + + if (ntevs == 0) { + *tevs = *tevs2; + *ntevs = ntevs2; + *tevs2 = NULL; + return 0; + } + + if (*ntevs + ntevs2 > probe_conf.max_probes) + ret = -E2BIG; + else { + /* Concatinate the array of probe_trace_event */ + new_tevs = memcat(*tevs, (*ntevs) * sizeof(**tevs), + *tevs2, ntevs2 * sizeof(**tevs2)); + if (!new_tevs) + ret = -ENOMEM; + else { + free(*tevs); + *tevs = new_tevs; + *ntevs += ntevs2; + } + } + if (ret < 0) + clear_probe_trace_events(*tevs2, ntevs2); + zfree(tevs2); + + return ret; +} + +/* + * Try to find probe_trace_event from given probe caches. Return the number + * of cached events found, if an error occurs return the error. + */ +static int find_cached_events(struct perf_probe_event *pev, + struct probe_trace_event **tevs, + const char *target) +{ + struct probe_cache *cache; + struct probe_cache_entry *entry; + struct probe_trace_event *tmp_tevs = NULL; + int ntevs = 0; + int ret = 0; + + cache = probe_cache__new(target); + /* Return 0 ("not found") if the target has no probe cache. */ + if (!cache) + return 0; + + for_each_probe_cache_entry(entry, cache) { + /* Skip the cache entry which has no name */ + if (!entry->pev.event || !entry->pev.group) + continue; + if ((!pev->group || strglobmatch(entry->pev.group, pev->group)) && + strglobmatch(entry->pev.event, pev->event)) { + ret = probe_cache_entry__get_event(entry, &tmp_tevs); + if (ret > 0) + ret = concat_probe_trace_events(tevs, &ntevs, + &tmp_tevs, ret); + if (ret < 0) + break; + } + } + probe_cache__delete(cache); + if (ret < 0) { + clear_probe_trace_events(*tevs, ntevs); + zfree(tevs); + } else { + ret = ntevs; + if (ntevs > 0 && target && target[0] == '/') + pev->uprobes = true; + } + + return ret; +} + static int find_probe_trace_events_from_cache(struct perf_probe_event *pev, struct probe_trace_event **tevs) { @@ -2903,6 +2998,10 @@ static int find_probe_trace_events_from_cache(struct perf_probe_event *pev, struct str_node *node; int ret, i; + if (pev->sdt) + /* For SDT/cached events, we use special search functions */ + return find_cached_events(pev, tevs, pev->target); + cache = probe_cache__new(pev->target); if (!cache) return 0; diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c index abfb05c..9aed9c3 100644 --- a/tools/perf/util/probe-file.c +++ b/tools/perf/util/probe-file.c @@ -362,13 +362,38 @@ probe_cache_entry__new(struct perf_probe_event *pev) return entry; } -/* For the kernel probe caches, pass target = NULL */ +int probe_cache_entry__get_event(struct probe_cache_entry *entry, + struct probe_trace_event **tevs) +{ + struct probe_trace_event *tev; + struct str_node *node; + int ret, i; + + ret = strlist__nr_entries(entry->tevlist); + if (ret > probe_conf.max_probes) + return -E2BIG; + + *tevs = zalloc(ret * sizeof(*tev)); + if (!*tevs) + return -ENOMEM; + + i = 0; + strlist__for_each_entry(node, entry->tevlist) { + tev = &(*tevs)[i++]; + ret = parse_probe_trace_command(node->s, tev); + if (ret < 0) + break; + } + return i; +} + +/* For the kernel probe caches, pass target = NULL or DSO__NAME_KALLSYMS */ static int probe_cache__open(struct probe_cache *pcache, const char *target) { char cpath[PATH_MAX]; char sbuildid[SBUILD_ID_SIZE]; char *dir_name = NULL; - bool is_kallsyms = !target; + bool is_kallsyms = false; int ret, fd; if (target && build_id_cache__cached(target)) { @@ -378,12 +403,13 @@ static int probe_cache__open(struct probe_cache *pcache, const char *target) goto found; } - if (target) - ret = filename__sprintf_build_id(target, sbuildid); - else { + if (!target || !strcmp(target, DSO__NAME_KALLSYMS)) { target = DSO__NAME_KALLSYMS; + is_kallsyms = true; ret = sysfs__sprintf_build_id("/", sbuildid); - } + } else + ret = filename__sprintf_build_id(target, sbuildid); + if (ret < 0) { pr_debug("Failed to get build-id from %s.\n", target); return ret; diff --git a/tools/perf/util/probe-file.h b/tools/perf/util/probe-file.h index d513b34..cafbe1d 100644 --- a/tools/perf/util/probe-file.h +++ b/tools/perf/util/probe-file.h @@ -34,6 +34,9 @@ int probe_file__get_events(int fd, struct strfilter *filter, struct strlist *plist); int probe_file__del_strlist(int fd, struct strlist *namelist); +int probe_cache_entry__get_event(struct probe_cache_entry *entry, + struct probe_trace_event **tevs); + struct probe_cache *probe_cache__new(const char *target); int probe_cache__add_entry(struct probe_cache *pcache, struct perf_probe_event *pev, -- cgit v1.1