From 4b3a2716dd785fabb9f6ac80c1d53cb29a88169d Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Sat, 9 Dec 2017 01:28:12 +0900 Subject: perf probe: Find versioned symbols from map Commit d80406453ad4 ("perf symbols: Allow user probes on versioned symbols") allows user to find default versioned symbols (with "@@") in map. However, it did not enable normal versioned symbol (with "@") for perf-probe. E.g. ===== # ./perf probe -x /lib64/libc-2.25.so malloc_get_state Failed to find symbol malloc_get_state in /usr/lib64/libc-2.25.so Error: Failed to add events. ===== This solves above issue by improving perf-probe symbol search function, as below. ===== # ./perf probe -x /lib64/libc-2.25.so malloc_get_state Added new event: probe_libc:malloc_get_state (on malloc_get_state in /usr/lib64/libc-2.25.so) You can now use it in all perf tools, such as: perf record -e probe_libc:malloc_get_state -aR sleep 1 # ./perf probe -l probe_libc:malloc_get_state (on malloc_get_state@GLIBC_2.2.5 in /usr/lib64/libc-2.25.so) ===== Signed-off-by: Masami Hiramatsu Reviewed-by: Thomas Richter Acked-by: Ravi Bangoria Tested-by: Arnaldo Carvalho de Melo Cc: Paul Clarke Cc: bhargavb Cc: linux-rt-users@vger.kernel.org Link: http://lkml.kernel.org/r/151275049269.24652.1639103455496216255.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/arch/powerpc/util/sym-handling.c | 8 ++++++++ tools/perf/util/probe-event.c | 20 ++++++++++++++++++-- tools/perf/util/symbol.c | 5 +++++ tools/perf/util/symbol.h | 1 + 4 files changed, 32 insertions(+), 2 deletions(-) diff --git a/tools/perf/arch/powerpc/util/sym-handling.c b/tools/perf/arch/powerpc/util/sym-handling.c index 9c4e23d..53d83d7 100644 --- a/tools/perf/arch/powerpc/util/sym-handling.c +++ b/tools/perf/arch/powerpc/util/sym-handling.c @@ -64,6 +64,14 @@ int arch__compare_symbol_names_n(const char *namea, const char *nameb, return strncmp(namea, nameb, n); } + +const char *arch__normalize_symbol_name(const char *name) +{ + /* Skip over initial dot */ + if (name && *name == '.') + name++; + return name; +} #endif #if defined(_CALL_ELF) && _CALL_ELF == 2 diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index a68141d..0d6c66d 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -2801,16 +2801,32 @@ static int find_probe_functions(struct map *map, char *name, int found = 0; struct symbol *sym; struct rb_node *tmp; + const char *norm, *ver; + char *buf = NULL; if (map__load(map) < 0) return 0; map__for_each_symbol(map, sym, tmp) { - if (strglobmatch(sym->name, name)) { + norm = arch__normalize_symbol_name(sym->name); + if (!norm) + continue; + + /* We don't care about default symbol or not */ + ver = strchr(norm, '@'); + if (ver) { + buf = strndup(norm, ver - norm); + if (!buf) + return -ENOMEM; + norm = buf; + } + if (strglobmatch(norm, name)) { found++; if (syms && found < probe_conf.max_probes) syms[found - 1] = sym; } + if (buf) + zfree(&buf); } return found; @@ -2856,7 +2872,7 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, * same name but different addresses, this lists all the symbols. */ num_matched_functions = find_probe_functions(map, pp->function, syms); - if (num_matched_functions == 0) { + if (num_matched_functions <= 0) { pr_err("Failed to find symbol %s in %s\n", pp->function, pev->target ? : "kernel"); ret = -ENOENT; diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 1b67a86..cc065d4 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -94,6 +94,11 @@ static int prefix_underscores_count(const char *str) return tail - str; } +const char * __weak arch__normalize_symbol_name(const char *name) +{ + return name; +} + int __weak arch__compare_symbol_names(const char *namea, const char *nameb) { return strcmp(namea, nameb); diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h index a4f0075..0563f33 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -349,6 +349,7 @@ bool elf__needs_adjust_symbols(GElf_Ehdr ehdr); void arch__sym_update(struct symbol *s, GElf_Sym *sym); #endif +const char *arch__normalize_symbol_name(const char *name); #define SYMBOL_A 0 #define SYMBOL_B 1 -- cgit v1.1