From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL for 4.14 09/97] perf probe: Find versioned symbols from map Date: Mon, 19 Mar 2018 15:54:31 +0000 Message-ID: <20180319155411.12348-9-alexander.levin@microsoft.com> References: <20180319155411.12348-1-alexander.levin@microsoft.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Cc: Masami Hiramatsu , Paul Clarke , bhargavb , "linux-rt-users@vger.kernel.org" , Arnaldo Carvalho de Melo , Sasha Levin To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Return-path: In-Reply-To: <20180319155411.12348-1-alexander.levin@microsoft.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-rt-users.vger.kernel.org From: Masami Hiramatsu [ Upstream commit 4b3a2716dd785fabb9f6ac80c1d53cb29a88169d ] 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. =3D=3D=3D=3D=3D # ./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. =3D=3D=3D=3D=3D This solves above issue by improving perf-probe symbol search function, as below. =3D=3D=3D=3D=3D # ./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-2.2= 5.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/li= b64/libc-2.25.so) =3D=3D=3D=3D=3D 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 Signed-off-by: Sasha Levin --- 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 9c4e23d8c8ce..53d83d7e6a09 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, cons= t char *nameb, =20 return strncmp(namea, nameb, n); } + +const char *arch__normalize_symbol_name(const char *name) +{ + /* Skip over initial dot */ + if (name && *name =3D=3D '.') + name++; + return name; +} #endif =20 #if defined(_CALL_ELF) && _CALL_ELF =3D=3D 2 diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index b7aaf9b2294d..c3cd3488fee7 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -2792,16 +2792,32 @@ static int find_probe_functions(struct map *map, ch= ar *name, int found =3D 0; struct symbol *sym; struct rb_node *tmp; + const char *norm, *ver; + char *buf =3D NULL; =20 if (map__load(map) < 0) return 0; =20 map__for_each_symbol(map, sym, tmp) { - if (strglobmatch(sym->name, name)) { + norm =3D arch__normalize_symbol_name(sym->name); + if (!norm) + continue; + + /* We don't care about default symbol or not */ + ver =3D strchr(norm, '@'); + if (ver) { + buf =3D strndup(norm, ver - norm); + if (!buf) + return -ENOMEM; + norm =3D buf; + } + if (strglobmatch(norm, name)) { found++; if (syms && found < probe_conf.max_probes) syms[found - 1] =3D sym; } + if (buf) + zfree(&buf); } =20 return found; @@ -2847,7 +2863,7 @@ static int find_probe_trace_events_from_map(struct pe= rf_probe_event *pev, * same name but different addresses, this lists all the symbols. */ num_matched_functions =3D find_probe_functions(map, pp->function, syms); - if (num_matched_functions =3D=3D 0) { + if (num_matched_functions <=3D 0) { pr_err("Failed to find symbol %s in %s\n", pp->function, pev->target ? : "kernel"); ret =3D -ENOENT; diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 6492ef38b090..4e8dd5fd45fd 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -93,6 +93,11 @@ static int prefix_underscores_count(const char *str) return tail - str; } =20 +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 6352022593c6..698c65e603a8 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -347,6 +347,7 @@ bool elf__needs_adjust_symbols(GElf_Ehdr ehdr); void arch__sym_update(struct symbol *s, GElf_Sym *sym); #endif =20 +const char *arch__normalize_symbol_name(const char *name); #define SYMBOL_A 0 #define SYMBOL_B 1 =20 --=20 2.14.1