From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752726AbbCVKRF (ORCPT ); Sun, 22 Mar 2015 06:17:05 -0400 Received: from terminus.zytor.com ([198.137.202.10]:57366 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751728AbbCVKRC (ORCPT ); Sun, 22 Mar 2015 06:17:02 -0400 Date: Sun, 22 Mar 2015 03:16:46 -0700 From: tip-bot for Arnaldo Carvalho de Melo Message-ID: Cc: dzickus@redhat.com, linux-kernel@vger.kernel.org, adrian.hunter@intel.com, tglx@linutronix.de, fweisbec@gmail.com, dsahern@gmail.com, hpa@zytor.com, eranian@google.com, namhyung@kernel.org, jolsa@redhat.com, mingo@kernel.org, bp@suse.de, acme@redhat.com Reply-To: mingo@kernel.org, namhyung@kernel.org, jolsa@redhat.com, acme@redhat.com, bp@suse.de, linux-kernel@vger.kernel.org, dzickus@redhat.com, dsahern@gmail.com, hpa@zytor.com, eranian@google.com, adrian.hunter@intel.com, tglx@linutronix.de, fweisbec@gmail.com To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf trace: Handle legacy syscalls tracepoints Git-Commit-ID: f208bd8df08d0659ecd9e09e992c79aab26cddfa X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: f208bd8df08d0659ecd9e09e992c79aab26cddfa Gitweb: http://git.kernel.org/tip/f208bd8df08d0659ecd9e09e992c79aab26cddfa Author: Arnaldo Carvalho de Melo AuthorDate: Fri, 20 Mar 2015 17:46:53 -0300 Committer: Arnaldo Carvalho de Melo CommitDate: Sat, 21 Mar 2015 14:53:36 -0300 perf trace: Handle legacy syscalls tracepoints Currently the code skips the first field with the expectation that it is 'nr'. But older kernels do not have the 'nr' field: field:int nr; offset:8; size:4; signed:1; Change perf-trace to drop the field if it exists after parsing the format file. This fixes the off-by-one problem with older kernels (e.g., RHEL6). e.g, perf-trace shows this for write: 1.515 ( 0.006 ms): dd/4245 write(buf: 2, count: 140733837536224 ) = 26 where 2 is really the fd, the huge number is really the buf address, etc. With this patch you get the more appropriate: 1.813 ( 0.003 ms): dd/6330 write(fd: 2, buf: 0x7fff22fc81f0, count: 25) = 25 Based-on-a-patch-by: David Ahern Acked-by: David Ahern Cc: Adrian Hunter Cc: Borislav Petkov Cc: Don Zickus Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-gvpdave4u2yq2jnzbcdznpvf@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-trace.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 6af6bce..001c6ae 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -1135,6 +1135,8 @@ static struct syscall_fmt *syscall_fmt__find(const char *name) struct syscall { struct event_format *tp_format; + int nr_args; + struct format_field *args; const char *name; bool filtered; bool is_exit; @@ -1442,14 +1444,14 @@ static int syscall__set_arg_fmts(struct syscall *sc) struct format_field *field; int idx = 0; - sc->arg_scnprintf = calloc(sc->tp_format->format.nr_fields - 1, sizeof(void *)); + sc->arg_scnprintf = calloc(sc->nr_args, sizeof(void *)); if (sc->arg_scnprintf == NULL) return -1; if (sc->fmt) sc->arg_parm = sc->fmt->arg_parm; - for (field = sc->tp_format->format.fields->next; field; field = field->next) { + for (field = sc->args; field; field = field->next) { if (sc->fmt && sc->fmt->arg_scnprintf[idx]) sc->arg_scnprintf[idx] = sc->fmt->arg_scnprintf[idx]; else if (field->flags & FIELD_IS_POINTER) @@ -1515,6 +1517,14 @@ static int trace__read_syscall_info(struct trace *trace, int id) if (sc->tp_format == NULL) return -1; + sc->args = sc->tp_format->format.fields; + sc->nr_args = sc->tp_format->format.nr_fields; + /* drop nr field - not relevant here; does not exist on older kernels */ + if (sc->args && strcmp(sc->args->name, "nr") == 0) { + sc->args = sc->args->next; + --sc->nr_args; + } + sc->is_exit = !strcmp(name, "exit_group") || !strcmp(name, "exit"); return syscall__set_arg_fmts(sc); @@ -1537,7 +1547,7 @@ static size_t syscall__scnprintf_args(struct syscall *sc, char *bf, size_t size, unsigned char *p; unsigned long val; - if (sc->tp_format != NULL) { + if (sc->args != NULL) { struct format_field *field; u8 bit = 1; struct syscall_arg arg = { @@ -1547,7 +1557,7 @@ static size_t syscall__scnprintf_args(struct syscall *sc, char *bf, size_t size, .thread = thread, }; - for (field = sc->tp_format->format.fields->next; field; + for (field = sc->args; field; field = field->next, ++arg.idx, bit <<= 1) { if (arg.mask & bit) continue;