Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933469AbaKMP37 (ORCPT ); Thu, 13 Nov 2014 10:29:59 -0500 Received: from mail-pd0-f172.google.com ([209.85.192.172]:33839 "EHLO mail-pd0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933279AbaKMP35 (ORCPT ); Thu, 13 Nov 2014 10:29:57 -0500 Date: Fri, 14 Nov 2014 00:30:17 +0900 From: Sergey Senozhatsky To: Mahendran Ganesh Cc: minchan@kernel.org, ngupta@vflare.org, ddstreet@ieee.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Sergey Senozhatsky Subject: Re: [PATCH 1/3] mm/zsmalloc: avoid unregister a NOT-registered zsmalloc zpool driver Message-ID: <20141113153017.GC1408@swordfish> References: <1415885857-5283-1-git-send-email-opensource.ganesh@gmail.com> <20141113152247.GB1408@swordfish> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20141113152247.GB1408@swordfish> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (11/14/14 00:22), Sergey Senozhatsky wrote: > > Now zsmalloc can be registered as a zpool driver into zpool when > > CONFIG_ZPOOL is enabled. During the init of zsmalloc, when error happens, > > we need to do cleanup. But in current code, it will unregister a not yet > > registered zsmalloc zpool driver(*zs_zpool_driver*). > > > > This patch puts the cleanup in zs_init() instead of calling zs_exit() > > where it will unregister a not-registered zpool driver. > > > > Signed-off-by: Mahendran Ganesh > > --- > > mm/zsmalloc.c | 12 ++++++++---- > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c > > index 839a48c..3d2bb36 100644 > > --- a/mm/zsmalloc.c > > +++ b/mm/zsmalloc.c > > @@ -907,10 +907,8 @@ static int zs_init(void) > > __register_cpu_notifier(&zs_cpu_nb); > > for_each_online_cpu(cpu) { > > ret = zs_cpu_notifier(NULL, CPU_UP_PREPARE, (void *)(long)cpu); > > - if (notifier_to_errno(ret)) { > > - cpu_notifier_register_done(); > > + if (notifier_to_errno(ret)) > > goto fail; > > - } > > } > > > > cpu_notifier_register_done(); > > @@ -920,8 +918,14 @@ static int zs_init(void) > > #endif > > > > return 0; > > + > > fail: > > - zs_exit(); > > + for_each_online_cpu(cpu) > > + zs_cpu_notifier(NULL, CPU_UP_CANCELED, (void *)(long)cpu); > > + __unregister_cpu_notifier(&zs_cpu_nb); > > + > > + cpu_notifier_register_done(); > > + > > return notifier_to_errno(ret); > > so we duplicate same code, and there is a bit confusing part > now: zs_cpu_notifier(CPU_UP_CANCELED) and zs_cpu_notifier(CPU_DEAD) > calls. > > > how about something like this? arghhh... silly me. sorry! this wasn't even compile tested. it should be zs_unregister_cpu_notifier(void). here it is. Factor out zsmalloc cpu notifier unregistration code and call it from both zs_exit() and zs_init() error path. Signed-off-by: Sergey Senozhatsky --- mm/zsmalloc.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index b3b57ef..8dda7c7 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -881,14 +881,10 @@ static struct notifier_block zs_cpu_nb = { .notifier_call = zs_cpu_notifier }; -static void zs_exit(void) +static void zs_unregister_cpu_notifier(void) { int cpu; -#ifdef CONFIG_ZPOOL - zpool_unregister_driver(&zs_zpool_driver); -#endif - cpu_notifier_register_begin(); for_each_online_cpu(cpu) @@ -898,6 +894,14 @@ static void zs_exit(void) cpu_notifier_register_done(); } +static void zs_exit(void) +{ +#ifdef CONFIG_ZPOOL + zpool_unregister_driver(&zs_zpool_driver); +#endif + zs_unregister_cpu_notifier(); +} + static int zs_init(void) { int cpu, ret; @@ -907,10 +911,8 @@ static int zs_init(void) __register_cpu_notifier(&zs_cpu_nb); for_each_online_cpu(cpu) { ret = zs_cpu_notifier(NULL, CPU_UP_PREPARE, (void *)(long)cpu); - if (notifier_to_errno(ret)) { - cpu_notifier_register_done(); + if (notifier_to_errno(ret)) goto fail; - } } cpu_notifier_register_done(); @@ -921,7 +923,7 @@ static int zs_init(void) return 0; fail: - zs_exit(); + zs_unregister_cpu_notifier(); return notifier_to_errno(ret); } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/