From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935599AbdGTJEJ (ORCPT ); Thu, 20 Jul 2017 05:04:09 -0400 Received: from terminus.zytor.com ([65.50.211.136]:50133 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933993AbdGTJEH (ORCPT ); Thu, 20 Jul 2017 05:04:07 -0400 Date: Thu, 20 Jul 2017 01:59:27 -0700 From: tip-bot for David Carrillo-Cisneros Message-ID: Cc: hpa@zytor.com, linux-kernel@vger.kernel.org, sque@chromium.org, namhyung@kernel.org, acme@redhat.com, eranian@google.com, peterz@infradead.org, jolsa@kernel.org, wangnan0@huawei.com, dsahern@gmail.com, ak@linux.intel.com, tglx@linutronix.de, mingo@kernel.org, pjt@google.com, mhiramat@kernel.org, hekuang@huawei.com, alexander.shishkin@linux.intel.com, davidcc@google.com Reply-To: peterz@infradead.org, acme@redhat.com, eranian@google.com, sque@chromium.org, namhyung@kernel.org, linux-kernel@vger.kernel.org, hpa@zytor.com, tglx@linutronix.de, ak@linux.intel.com, dsahern@gmail.com, wangnan0@huawei.com, jolsa@kernel.org, pjt@google.com, mingo@kernel.org, davidcc@google.com, alexander.shishkin@linux.intel.com, hekuang@huawei.com, mhiramat@kernel.org In-Reply-To: <20170718042549.145161-5-davidcc@google.com> References: <20170718042549.145161-5-davidcc@google.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf util: Add const modifier to buf in "writen" function Git-Commit-ID: 7c72440506e2108494bab3b68a4118fa61a9dbf4 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: 7c72440506e2108494bab3b68a4118fa61a9dbf4 Gitweb: http://git.kernel.org/tip/7c72440506e2108494bab3b68a4118fa61a9dbf4 Author: David Carrillo-Cisneros AuthorDate: Mon, 17 Jul 2017 21:25:37 -0700 Committer: Arnaldo Carvalho de Melo CommitDate: Tue, 18 Jul 2017 23:14:29 -0300 perf util: Add const modifier to buf in "writen" function Make buf in helper function "writen" constant to simplify the life of its callers. This requires to hack a cast of buf prior to passing it to "ion" which is simpler than the alternative of reworking the "ion" function to provide a read and a write paths, the latter with constant buf argument. Signed-off-by: David Carrillo-Cisneros Acked-by: David Ahern Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: He Kuang Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Paul Turner Cc: Peter Zijlstra Cc: Simon Que Cc: Stephane Eranian Cc: Wang Nan Link: http://lkml.kernel.org/r/20170718042549.145161-5-davidcc@google.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/util.c | 6 ++++-- tools/perf/util/util.h | 2 +- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c index 9e4ea85..4c360da 100644 --- a/tools/perf/util/util.c +++ b/tools/perf/util/util.c @@ -281,6 +281,7 @@ static ssize_t ion(bool is_read, int fd, void *buf, size_t n) size_t left = n; while (left) { + /* buf must be treated as const if !is_read. */ ssize_t ret = is_read ? read(fd, buf, left) : write(fd, buf, left); @@ -308,9 +309,10 @@ ssize_t readn(int fd, void *buf, size_t n) /* * Write exactly 'n' bytes or return an error. */ -ssize_t writen(int fd, void *buf, size_t n) +ssize_t writen(int fd, const void *buf, size_t n) { - return ion(false, fd, buf, n); + /* ion does not modify buf. */ + return ion(false, fd, (void *)buf, n); } size_t hex_width(u64 v) diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h index 062dd20..b136c27 100644 --- a/tools/perf/util/util.h +++ b/tools/perf/util/util.h @@ -38,7 +38,7 @@ int copyfile_ns(const char *from, const char *to, struct nsinfo *nsi); int copyfile_offset(int fromfd, loff_t from_ofs, int tofd, loff_t to_ofs, u64 size); ssize_t readn(int fd, void *buf, size_t n); -ssize_t writen(int fd, void *buf, size_t n); +ssize_t writen(int fd, const void *buf, size_t n); size_t hex_width(u64 v); int hex2u64(const char *ptr, u64 *val);