From patchwork Mon Nov 23 12:21:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 330662 Delivered-To: patch@linaro.org Received: by 2002:a92:ae0b:0:0:0:0:0 with SMTP id s11csp1966865ilh; Mon, 23 Nov 2020 04:47:43 -0800 (PST) X-Google-Smtp-Source: ABdhPJwCshW6V+DnkRIk01QqevqrYp6gc22OjI6/kxY4kJV6nwhO3mct+2oleAiUPfA/x7eQFndl X-Received: by 2002:a05:6402:150b:: with SMTP id f11mr26865136edw.332.1606135663251; Mon, 23 Nov 2020 04:47:43 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1606135663; cv=none; d=google.com; s=arc-20160816; b=PFf+KX3h0l/J/PlKAjKSPrVxMm/em8OxP9cwTsfxaS6t0uOhdZUJP8lxrIrzzMQkrs tan2pqEgKnllBL8R0AonSCEADo/3e0/OwMy/tqjWXkgXSP2WsHAvuRbdqhylxlW5TmVf 8c5eZUMw40YRBKXP4MJ/Pn92aZp9Jmyu1ArnDfQmF5YMYxK5NBtqNPrmGg3rk7nltIlJ gImwmJ07eoY9zhOdMdt7UiAzvO9ILIBs8OwKHrrk9oDubAAQWEnQTPiBJ8uJJYpoDuga ovezolT6+hDIOdwrDhvi0KyhtEureln3GGwh74gIioYhY+VbtPMf3iOSE7RMTp73c1MO G4tQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=aHrG+FQMqEKnQ4ff98bSLQjZ/B7k3YTNarBPgd/5UP0=; b=najfCyP6+ZY/13jlDeYd1ED7yDPhsc347Lft2Kf5nnfysIRAzryxO5q3/wzICsENw1 9R3I7t9kLWtBls/Go7GkZKS236lb99imjSM+HBzIKHHMRJ8S/lNo8Wy8zaAcgZxzij5g EEEuL1vNqICcEGwIFfr+NQ0POhYMBZpC+6/ws2F20/zklTH4XgTP1N1qlipc0E2c8D1R /TgOA3mj8L78RgLpywmDuyKUd6/WmVi7SrjCoHA3yXl6wbh5KiYsADVgsyBQWCbAshMj sd+1jvYGAFb8aVa3xReXh8DKOjCQ91SQ+CZbBoxbkz3hRc+Y4HLYBc4SXvQFcmjfd7j/ XVeQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=KoX+aHuV; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id g17si6809070edy.62.2020.11.23.04.47.43; Mon, 23 Nov 2020 04:47:43 -0800 (PST) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=KoX+aHuV; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732751AbgKWMqd (ORCPT + 14 others); Mon, 23 Nov 2020 07:46:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:60066 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732740AbgKWMq3 (ORCPT ); Mon, 23 Nov 2020 07:46:29 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F0EE3208C3; Mon, 23 Nov 2020 12:46:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1606135588; bh=YhRyQ/YJFXdK7Ox66tX6f5/svd923I0mNeQygINnzZc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KoX+aHuVRxIB0T4YUXAfDx85qZNjLVCRJjoFQqYHJYMZH2YFDUpPHjbO58fgqF6RY UZNRJ9pAALC1EGpYzyNokYCxbRrZIX4hXitsqSQjJthif3HI7Wh4Ymz5UqXTLAe1sx D4LE3nSeIwS45gaWiMwxbgxVB/7Xg+px923/DWPA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Leo Yan , Jiri Olsa , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH 5.9 123/252] perf lock: Dont free "lock_seq_stat" if read_count isnt zero Date: Mon, 23 Nov 2020 13:21:13 +0100 Message-Id: <20201123121841.528847251@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201123121835.580259631@linuxfoundation.org> References: <20201123121835.580259631@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Leo Yan [ Upstream commit b0e5a05cc9e37763c7f19366d94b1a6160c755bc ] When execute command "perf lock report", it hits failure and outputs log as follows: perf: builtin-lock.c:623: report_lock_release_event: Assertion `!(seq->read_count < 0)' failed. Aborted This is an imbalance issue. The locking sequence structure "lock_seq_stat" contains the reader counter and it is used to check if the locking sequence is balance or not between acquiring and releasing. If the tool wrongly frees "lock_seq_stat" when "read_count" isn't zero, the "read_count" will be reset to zero when allocate a new structure at the next time; thus it causes the wrong counting for reader and finally results in imbalance issue. To fix this issue, if detects "read_count" is not zero (means still have read user in the locking sequence), goto the "end" tag to skip freeing structure "lock_seq_stat". Fixes: e4cef1f65061 ("perf lock: Fix state machine to recognize lock sequence") Signed-off-by: Leo Yan Acked-by: Jiri Olsa Link: https://lore.kernel.org/r/20201104094229.17509-2-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/builtin-lock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.27.0 diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c index 5cecc1ad78e1f..a2f1e53f37a7a 100644 --- a/tools/perf/builtin-lock.c +++ b/tools/perf/builtin-lock.c @@ -621,7 +621,7 @@ static int report_lock_release_event(struct evsel *evsel, case SEQ_STATE_READ_ACQUIRED: seq->read_count--; BUG_ON(seq->read_count < 0); - if (!seq->read_count) { + if (seq->read_count) { ls->nr_release++; goto end; }