From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10124C433F5 for ; Fri, 20 May 2022 15:56:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351278AbiETP4o (ORCPT ); Fri, 20 May 2022 11:56:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351276AbiETP43 (ORCPT ); Fri, 20 May 2022 11:56:29 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D91F53A7C for ; Fri, 20 May 2022 08:56:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1653062171; x=1684598171; h=message-id:date:mime-version:subject:from:to:cc: references:in-reply-to:content-transfer-encoding; bh=QKc/EhjtozyiIqZXJMmyuE7NaobnHY6+1jw25/G7tsY=; b=ewvsxq3j1N5xGGG7niEJgFD8QGUv6ejhAtESExWKOcesdonzBuiuAP6L fL1l01W4COPICOsbO22ZjrYGv2EhHwK1vDI0FebwU6t/I04zITY2C+13b PUnkL7LkIiIaGl2GoO/MExZwO5/KP0IMGRe5Cr0k/3CkQ2YAwSJ1/3Jzq h+zTzzVtWL3I8DknyVKj4PxX0yc41GGeEzW0WOA42MjOazJFC5D5xHKd4 M/Dr+1lUGqkGj+HkILqhCV3/Y+C0DnUmJ5S9OXBXemnLQezOaIRqybK3x 5ScJy6m6U2LEoxE3gxrS7Y6VsVNIZXmPsOTdBoDKbYgndaJRSaHR48py9 g==; X-IronPort-AV: E=McAfee;i="6400,9594,10353"; a="335700246" X-IronPort-AV: E=Sophos;i="5.91,239,1647327600"; d="scan'208";a="335700246" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 May 2022 08:56:10 -0700 X-IronPort-AV: E=Sophos;i="5.91,239,1647327600"; d="scan'208";a="599284945" Received: from ahunter6-mobl1.ger.corp.intel.com (HELO [10.0.2.15]) ([10.252.38.124]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 May 2022 08:56:09 -0700 Message-ID: Date: Fri, 20 May 2022 18:56:04 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Firefox/91.0 Thunderbird/91.8.1 Subject: [PATCH V2 2/5] libperf: Add preadn() Content-Language: en-US From: Adrian Hunter To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , Namhyung Kim , linux-kernel@vger.kernel.org References: <20220520132404.25853-1-adrian.hunter@intel.com> <20220520132404.25853-3-adrian.hunter@intel.com> Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki In-Reply-To: <20220520132404.25853-3-adrian.hunter@intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add preadn() to provide pread() and readn() semantics. Signed-off-by: Adrian Hunter --- Changes in V2: Make preadn() thread-safe in case someone infers from the name that it is. tools/lib/perf/include/internal/lib.h | 2 ++ tools/lib/perf/lib.c | 20 ++++++++++++++++++++ 2 files changed, 22 insertions(+) diff --git a/tools/lib/perf/include/internal/lib.h b/tools/lib/perf/include/internal/lib.h index 5175d491b2d49..85471a4b900f7 100644 --- a/tools/lib/perf/include/internal/lib.h +++ b/tools/lib/perf/include/internal/lib.h @@ -9,4 +9,6 @@ extern unsigned int page_size; ssize_t readn(int fd, void *buf, size_t n); ssize_t writen(int fd, const void *buf, size_t n); +ssize_t preadn(int fd, void *buf, size_t n, off_t offs); + #endif /* __LIBPERF_INTERNAL_CPUMAP_H */ diff --git a/tools/lib/perf/lib.c b/tools/lib/perf/lib.c index 18658931fc714..696fb0ea67c6e 100644 --- a/tools/lib/perf/lib.c +++ b/tools/lib/perf/lib.c @@ -38,6 +38,26 @@ ssize_t readn(int fd, void *buf, size_t n) return ion(true, fd, buf, n); } +ssize_t preadn(int fd, void *buf, size_t n, off_t offs) +{ + size_t left = n; + + while (left) { + ssize_t ret = pread(fd, buf, left, offs); + + if (ret < 0 && errno == EINTR) + continue; + if (ret <= 0) + return ret; + + left -= ret; + buf += ret; + offs += ret; + } + + return n; +} + /* * Write exactly 'n' bytes or return an error. */ -- 2.34.1