Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965865AbdCXSsB (ORCPT ); Fri, 24 Mar 2017 14:48:01 -0400 Received: from terminus.zytor.com ([65.50.211.136]:58873 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965825AbdCXSrt (ORCPT ); Fri, 24 Mar 2017 14:47:49 -0400 Date: Fri, 24 Mar 2017 11:44:19 -0700 From: tip-bot for Alexis Berlemont Message-ID: Cc: linux-kernel@vger.kernel.org, acme@redhat.com, mhiramat@kernel.org, peterz@infradead.org, ravi.bangoria@linux.vnet.ibm.com, alexis.berlemont@gmail.com, hpa@zytor.com, mingo@kernel.org, alexander.shishkin@linux.intel.com, hemant@linux.vnet.ibm.com, tglx@linutronix.de Reply-To: acme@redhat.com, linux-kernel@vger.kernel.org, mhiramat@kernel.org, peterz@infradead.org, ravi.bangoria@linux.vnet.ibm.com, alexis.berlemont@gmail.com, hemant@linux.vnet.ibm.com, hpa@zytor.com, alexander.shishkin@linux.intel.com, mingo@kernel.org, tglx@linutronix.de In-Reply-To: <20161214000732.1710-2-alexis.berlemont@gmail.com> References: <20161214000732.1710-2-alexis.berlemont@gmail.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf sdt: Add scanning of sdt probes arguments Git-Commit-ID: be88184b1c7054719296387c6063748fb48fa645 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 Content-Length: 3531 Lines: 99 Commit-ID: be88184b1c7054719296387c6063748fb48fa645 Gitweb: http://git.kernel.org/tip/be88184b1c7054719296387c6063748fb48fa645 Author: Alexis Berlemont AuthorDate: Wed, 14 Dec 2016 01:07:31 +0100 Committer: Arnaldo Carvalho de Melo CommitDate: Tue, 21 Mar 2017 10:56:28 -0300 perf sdt: Add scanning of sdt probes arguments During a "perf buildid-cache --add" command, the section ".note.stapsdt" of the "added" binary is scanned in order to list the available SDT markers available in a binary. The parts containing the probes arguments were left unscanned. The whole section is now parsed; the probe arguments are extracted for later use. Signed-off-by: Alexis Berlemont Acked-by: Masami Hiramatsu Cc: Alexander Shishkin Cc: Hemant Kumar Cc: Peter Zijlstra Cc: Ravi Bangoria Link: http://lkml.kernel.org/r/20161214000732.1710-2-alexis.berlemont@gmail.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/symbol-elf.c | 25 +++++++++++++++++++++++-- tools/perf/util/symbol.h | 1 + 2 files changed, 24 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 4e59dde..0e660db 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -1828,7 +1828,7 @@ void kcore_extract__delete(struct kcore_extract *kce) static int populate_sdt_note(Elf **elf, const char *data, size_t len, struct list_head *sdt_notes) { - const char *provider, *name; + const char *provider, *name, *args; struct sdt_note *tmp = NULL; GElf_Ehdr ehdr; GElf_Addr base_off = 0; @@ -1887,6 +1887,25 @@ static int populate_sdt_note(Elf **elf, const char *data, size_t len, goto out_free_prov; } + args = memchr(name, '\0', data + len - name); + + /* + * There is no argument if: + * - We reached the end of the note; + * - There is not enough room to hold a potential string; + * - The argument string is empty or just contains ':'. + */ + if (args == NULL || data + len - args < 2 || + args[1] == ':' || args[1] == '\0') + tmp->args = NULL; + else { + tmp->args = strdup(++args); + if (!tmp->args) { + ret = -ENOMEM; + goto out_free_name; + } + } + if (gelf_getclass(*elf) == ELFCLASS32) { memcpy(&tmp->addr, &buf, 3 * sizeof(Elf32_Addr)); tmp->bit32 = true; @@ -1898,7 +1917,7 @@ static int populate_sdt_note(Elf **elf, const char *data, size_t len, if (!gelf_getehdr(*elf, &ehdr)) { pr_debug("%s : cannot get elf header.\n", __func__); ret = -EBADF; - goto out_free_name; + goto out_free_args; } /* Adjust the prelink effect : @@ -1923,6 +1942,8 @@ static int populate_sdt_note(Elf **elf, const char *data, size_t len, list_add_tail(&tmp->note_list, sdt_notes); return 0; +out_free_args: + free(tmp->args); out_free_name: free(tmp->name); out_free_prov: diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h index 6c358b7..9222c7e 100644 --- a/tools/perf/util/symbol.h +++ b/tools/perf/util/symbol.h @@ -351,6 +351,7 @@ int arch__choose_best_symbol(struct symbol *syma, struct symbol *symb); struct sdt_note { char *name; /* name of the note*/ char *provider; /* provider name */ + char *args; bool bit32; /* whether the location is 32 bits? */ union { /* location, base and semaphore addrs */ Elf64_Addr a64[3];