From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933342AbdKGAIT (ORCPT ); Mon, 6 Nov 2017 19:08:19 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:52572 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932778AbdKFXyb (ORCPT ); Mon, 6 Nov 2017 18:54:31 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Bart Van Assche" , "Mike Snitzer" Date: Mon, 06 Nov 2017 23:03:02 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 154/294] dm: fix printk() rate limiting code In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.50-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche commit 604407890ecf624c2fb41013c82b22aade59b455 upstream. Using the same rate limiting state for different kinds of messages is wrong because this can cause a high frequency message to suppress a report of a low frequency message. Hence use a unique rate limiting state per message type. Fixes: 71a16736a15e ("dm: use local printk ratelimit") Signed-off-by: Bart Van Assche Signed-off-by: Mike Snitzer Signed-off-by: Ben Hutchings --- drivers/md/dm.c | 10 ---------- include/linux/device-mapper.h | 41 ++++++++++++----------------------------- 2 files changed, 12 insertions(+), 39 deletions(-) --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -24,16 +24,6 @@ #define DM_MSG_PREFIX "core" -#ifdef CONFIG_PRINTK -/* - * ratelimit state to be used in DMXXX_LIMIT(). - */ -DEFINE_RATELIMIT_STATE(dm_ratelimit_state, - DEFAULT_RATELIMIT_INTERVAL, - DEFAULT_RATELIMIT_BURST); -EXPORT_SYMBOL(dm_ratelimit_state); -#endif - /* * Cookies are numeric values sent with CHANGE and REMOVE * uevents while resuming, removing or renaming the device. --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -481,46 +481,29 @@ void *dm_vcalloc(unsigned long nmemb, un *---------------------------------------------------------------*/ #define DM_NAME "device-mapper" -#ifdef CONFIG_PRINTK -extern struct ratelimit_state dm_ratelimit_state; - -#define dm_ratelimit() __ratelimit(&dm_ratelimit_state) -#else -#define dm_ratelimit() 0 -#endif +#define DM_RATELIMIT(pr_func, fmt, ...) \ +do { \ + static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL, \ + DEFAULT_RATELIMIT_BURST); \ + \ + if (__ratelimit(&rs)) \ + pr_func(DM_FMT(fmt), ##__VA_ARGS__); \ +} while (0) #define DM_FMT(fmt) DM_NAME ": " DM_MSG_PREFIX ": " fmt "\n" #define DMCRIT(fmt, ...) pr_crit(DM_FMT(fmt), ##__VA_ARGS__) #define DMERR(fmt, ...) pr_err(DM_FMT(fmt), ##__VA_ARGS__) -#define DMERR_LIMIT(fmt, ...) \ -do { \ - if (dm_ratelimit()) \ - DMERR(fmt, ##__VA_ARGS__); \ -} while (0) - +#define DMERR_LIMIT(fmt, ...) DM_RATELIMIT(pr_err, fmt, ##__VA_ARGS__) #define DMWARN(fmt, ...) pr_warn(DM_FMT(fmt), ##__VA_ARGS__) -#define DMWARN_LIMIT(fmt, ...) \ -do { \ - if (dm_ratelimit()) \ - DMWARN(fmt, ##__VA_ARGS__); \ -} while (0) - +#define DMWARN_LIMIT(fmt, ...) DM_RATELIMIT(pr_warn, fmt, ##__VA_ARGS__) #define DMINFO(fmt, ...) pr_info(DM_FMT(fmt), ##__VA_ARGS__) -#define DMINFO_LIMIT(fmt, ...) \ -do { \ - if (dm_ratelimit()) \ - DMINFO(fmt, ##__VA_ARGS__); \ -} while (0) +#define DMINFO_LIMIT(fmt, ...) DM_RATELIMIT(pr_info, fmt, ##__VA_ARGS__) #ifdef CONFIG_DM_DEBUG #define DMDEBUG(fmt, ...) printk(KERN_DEBUG DM_FMT(fmt), ##__VA_ARGS__) -#define DMDEBUG_LIMIT(fmt, ...) \ -do { \ - if (dm_ratelimit()) \ - DMDEBUG(fmt, ##__VA_ARGS__); \ -} while (0) +#define DMDEBUG_LIMIT(fmt, ...) DM_RATELIMIT(pr_debug, fmt, ##__VA_ARGS__) #else #define DMDEBUG(fmt, ...) no_printk(fmt, ##__VA_ARGS__) #define DMDEBUG_LIMIT(fmt, ...) no_printk(fmt, ##__VA_ARGS__)