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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 B5D0EC2BC61 for ; Tue, 30 Oct 2018 07:55:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B64F20823 for ; Tue, 30 Oct 2018 07:55:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6B64F20823 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=xiaomi.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726491AbeJ3QrU (ORCPT ); Tue, 30 Oct 2018 12:47:20 -0400 Received: from outboundhk.mxmail.xiaomi.com ([207.226.244.126]:52637 "EHLO outboundhk.mxmail.xiaomi.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726196AbeJ3QrU (ORCPT ); Tue, 30 Oct 2018 12:47:20 -0400 X-AuditID: 0a3808ce-4afff70000012663-85-5bd80ddce9e1 Received: from xiaomi.com (cnbox2.mioffice.cn [10.237.8.142]) by outboundhk.mxmail.xiaomi.com (xiaomi.com) with SMTP id D7.77.09827.CDD08DB5; Tue, 30 Oct 2018 15:53:00 +0800 (HKT) Received: from localhost (10.237.91.193) by cnbox2.mioffice.cn (10.237.8.142) with Microsoft SMTP Server (TLS) id 15.0.1365.1; Tue, 30 Oct 2018 15:52:59 +0800 From: Peng Wang To: , , , , CC: , , Peng Wang Subject: [PATCH v4] pstore: Avoid duplicate call of persistent_ram_zap() Date: Tue, 30 Oct 2018 15:52:34 +0800 Message-ID: <20181030075234.21137-1-wangpeng15@xiaomi.com> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.237.91.193] X-ClientProxiedBy: CNCAS1.mioffice.cn (10.237.8.131) To cnbox2.mioffice.cn (10.237.8.142) X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrGLMWRmVeSWpSXmKPExsXC9ZajT/cO741og9uv1C0ObtW02L7xG6vF sgZVizPduRaXd81hs3hz4R6Lxcmfy1kd2D227d7G6jG74SKLx4T+T4weO2fdZfdYvOclk8fC T19ZPT5vkgtgj+KySUnNySxLLdK3S+DK2Ln/N2vBZaGKd3ffMTUwdvF3MXJySAiYSFy4eIm9 i5GLQ0hgK6PEh4mbWCCcRYwS805fYQepYhNQl+je3gVmiwhUSFzdf4kNxGYWSJK48ekCmC0s 4CGx9NxJVhCbRUBV4sq3v2A2r4CVxL2JL9ggtslLNOzazA4RF5Q4OfMJC8QceYnmrbOZIWwJ iYMvXoDZQgJKEhuutwP1cgD1Kkr8+h8LMSZa4sHvGWwTGAVmIZk0C8mkWUgmLWBkXsUomZGf l54NxMUFibmGermZ+Wlpmcmpesl5mxhBoW/BcW4H44R3qYcYBTgYlXh4G/SuRwuxJpYVV+Ye YpTgYFYS4Q3muhEtxJuSWFmVWpQfX1Sak1p8iFGag0VJnNeg8UC0kEB6YklqdmpqQWoRTJaJ g1OqgdFhTvvWYtG5KWF3nFaUymStUPp2tzI3bfnC0P8Tf1peSpvuZKZz93qwi0/wtGWVb42K zySqh/hGdk9z14pjcr70RfT2VWFjGxbRYo3pS6LkLPzuPHitt4RJ9u42ToOjL7i4T/24MDuv dkN9z6U/MXsX7WC5XD7TzeZd1dUVe5y2fnbZfGnHx2QlluKMREMt5qLiRADSMDL6eQIAAA== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When initialing prz with invalid data in buffer(no PERSISTENT_RAM_SIG), function call path is like this: ramoops_init_prz -> | |-> persistent_ram_new -> persistent_ram_post_init -> persistent_ram_zap | |-> persistent_ram_zap As we can see, persistent_ram_zap() is called twice. We can avoid this by adding an option to persistent_ram_new(), and only call persistent_ram_zap() when it is needed. Signed-off-by: Peng Wang --- fs/pstore/ram.c | 4 +--- fs/pstore/ram_core.c | 5 +++-- include/linux/pstore_ram.h | 1 + 3 files changed, 5 insertions(+), 5 deletions(-) diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index ffcff6516e89..b51901f97dc2 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -640,7 +640,7 @@ static int ramoops_init_prz(const char *name, label = kasprintf(GFP_KERNEL, "ramoops:%s", name); *prz = persistent_ram_new(*paddr, sz, sig, &cxt->ecc_info, - cxt->memtype, 0, label); + cxt->memtype, PRZ_FLAG_ZAP_OLD, label); if (IS_ERR(*prz)) { int err = PTR_ERR(*prz); @@ -649,8 +649,6 @@ static int ramoops_init_prz(const char *name, return err; } - persistent_ram_zap(*prz); - *paddr += sz; return 0; diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c index 12e21f789194..2ededd1ea1c2 100644 --- a/fs/pstore/ram_core.c +++ b/fs/pstore/ram_core.c @@ -505,15 +505,16 @@ static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig, pr_debug("found existing buffer, size %zu, start %zu\n", buffer_size(prz), buffer_start(prz)); persistent_ram_save_old(prz); - return 0; + if (!(prz->flags & PRZ_FLAG_ZAP_OLD)) + return 0; } } else { pr_debug("no valid data in buffer (sig = 0x%08x)\n", prz->buffer->sig); + prz->buffer->sig = sig; } /* Rewind missing or invalid memory area. */ - prz->buffer->sig = sig; persistent_ram_zap(prz); return 0; diff --git a/include/linux/pstore_ram.h b/include/linux/pstore_ram.h index 602d64725222..6e94980357d2 100644 --- a/include/linux/pstore_ram.h +++ b/include/linux/pstore_ram.h @@ -30,6 +30,7 @@ * PRZ_FLAG_NO_LOCK is used. For all other cases, locking is required. */ #define PRZ_FLAG_NO_LOCK BIT(0) +#define PRZ_FLAG_ZAP_OLD BIT(1) struct persistent_ram_buffer; struct rs_control; -- 2.19.1