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 X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7583BC3A5A1 for ; Wed, 28 Aug 2019 08:57:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C4EA2189D for ; Wed, 28 Aug 2019 08:57:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="JG6Z7Gxg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726436AbfH1I5y (ORCPT ); Wed, 28 Aug 2019 04:57:54 -0400 Received: from mail-wm1-f65.google.com ([209.85.128.65]:40810 "EHLO mail-wm1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726293AbfH1I5x (ORCPT ); Wed, 28 Aug 2019 04:57:53 -0400 Received: by mail-wm1-f65.google.com with SMTP id t9so805768wmi.5 for ; Wed, 28 Aug 2019 01:57:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=bJAVvyqSeoa1jAnD2+HN2Roj8blocYF3Ubt/w/PAf4I=; b=JG6Z7GxglODV+p68avG+73XPcrhgj3oQ8lEnHpbvry4Ex0rZq95XhLwNS4e1HUPfKa mUmQFNJ/NyukLkn29DDAhVGXiIUsN+pqPIFg2tE+28xABcL7sxLFj6Lz2YTL5Sij263S 2+Pzeh6FdCpnGxePElKrFMh3TcFz5IBwUeIh9Y5SoAe5hpleLMPyE3jiFPIFh5LNNQcH 4D5SdJQixXItITrUYIdqjBlsgRTmPvauZ3iKNmstnoFPvdDmta2MXp8+GQ5QA1fxNAIK a7tMZNTEin1f2+hIzC47mWkrmGYfv8NXu03unCfl5j6NPd6UP7z0pyF7eCco82ydbQd7 nZAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=bJAVvyqSeoa1jAnD2+HN2Roj8blocYF3Ubt/w/PAf4I=; b=pkZUSLAKdZ6bqwxDQD4KX1WulCWf2B3Lk8ZWkYAG+F5YyBDbNBpdZfhy/kdUpO+idh /vixuTdRRb1vVwjzS8LoHlm2Se/0hnnGPk9YHrBwa3OXqH77nL9iSktuFdiiZzgGCi3j YGUYXePiznKuhorpIMfJWtDF4hWNsIt7bkc87b0G88N7uvEs1FW2xUoDsuT5oT5GKRps rYGtpnhZcZ3gLtmUmccc0b4Y0tmZhvizImQl67YBsd1p3MdKV6Q0pYcjDouTsjoGaJin mqWiZprn+WQ8VThkhR3QctQhw/EvVrHFdhSDvoiGXfU7VLHVPXQWyEvX0w4FfDL8tn2A L/1g== X-Gm-Message-State: APjAAAXoIOTw/yvpXMQTh9o6zwDVayaG8iDSsoLzG50RZgjzOf9Sfyv6 kQ5jKn69cO2DTkeoTE1mjzuXoefj X-Google-Smtp-Source: APXvYqxjdAKoC3a0p1bTDdAcbz8vL98NR9z7kLuc5KwLTCaxoZgpK7NY37hame73UXAAQV9L6+42Xw== X-Received: by 2002:a7b:c95a:: with SMTP id i26mr3559174wml.175.1566982671606; Wed, 28 Aug 2019 01:57:51 -0700 (PDT) Received: from oberon.eng.vmware.com ([146.247.46.5]) by smtp.gmail.com with ESMTPSA id u186sm2579433wmu.26.2019.08.28.01.57.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Aug 2019 01:57:51 -0700 (PDT) From: "Tzvetomir Stoyanov (VMware)" To: rostedt@goodmis.org Cc: linux-trace-devel@vger.kernel.org Subject: [PATCH v12 3/9] trace-cmd: Fix tracecmd_read_page_record() to read more than one event Date: Wed, 28 Aug 2019 11:57:40 +0300 Message-Id: <20190828085746.26231-4-tz.stoyanov@gmail.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190828085746.26231-1-tz.stoyanov@gmail.com> References: <20190828085746.26231-1-tz.stoyanov@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org From: Tzvetomir Stoyanov The kbuffer_next_event() will return the next event on the sub buffer. If we pass in the last_record to tracecmd_read_page_record(), it initializes the sub buffer, and by calling kbuffer_next_event() (instead of kbuffer_read_event()), the second event on the sub buffer is returned. This causes the match of the last_record not to match if the last_record happens to be the first event on the sub buffer. Signed-off-by: Tzvetomir Stoyanov --- lib/trace-cmd/trace-input.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/lib/trace-cmd/trace-input.c b/lib/trace-cmd/trace-input.c index 05e595f..3bb17f9 100644 --- a/lib/trace-cmd/trace-input.c +++ b/lib/trace-cmd/trace-input.c @@ -1720,18 +1720,22 @@ tracecmd_read_page_record(struct tep_handle *pevent, void *page, int size, goto out_free; } - do { + ptr = kbuffer_read_event(kbuf, &ts); + while (ptr < last_record->data) { ptr = kbuffer_next_event(kbuf, NULL); if (!ptr) break; - } while (ptr < last_record->data); + if (ptr == last_record->data) + break; + } if (ptr != last_record->data) { warning("tracecmd_read_page_record: could not find last_record"); goto out_free; } - } + ptr = kbuffer_next_event(kbuf, &ts); + } else + ptr = kbuffer_read_event(kbuf, &ts); - ptr = kbuffer_read_event(kbuf, &ts); if (!ptr) goto out_free; -- 2.21.0