Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752132Ab0LAF2Y (ORCPT ); Wed, 1 Dec 2010 00:28:24 -0500 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:58710 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750950Ab0LAF2X (ORCPT ); Wed, 1 Dec 2010 00:28:23 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: KOSAKI Motohiro Subject: [PATCH 1/2] mem-hotplug: Introduce {un}lock_memory_hotplug() Cc: kosaki.motohiro@jp.fujitsu.com, Hugh Dickins , Andrew Morton , Andrea Arcangeli , Andi Kleen , LKML , linux-mm , KAMEZAWA Hiroyuki In-Reply-To: <20101026163218.B7BF.A69D9226@jp.fujitsu.com> References: <20101026163218.B7BF.A69D9226@jp.fujitsu.com> Message-Id: <20101201142722.ABCB.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.50.07 [ja] Date: Wed, 1 Dec 2010 14:28:19 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4622 Lines: 174 Now, hwpoison are using lock_system_sleep() for prevent a race with memory hotplug. However lock_system_sleep() is no-op if CONFIG_HIBERNATION=n. Therefore we need new lock. Cc: Andi Kleen Cc: Kamezawa Hiroyuki Suggested-by: Hugh Dickins Signed-off-by: KOSAKI Motohiro --- include/linux/memory_hotplug.h | 6 ++++++ mm/memory-failure.c | 8 ++++---- mm/memory_hotplug.c | 31 ++++++++++++++++++++++++------- 3 files changed, 34 insertions(+), 11 deletions(-) diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 4307231..31c237a 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -161,6 +161,9 @@ extern void register_page_bootmem_info_node(struct pglist_data *pgdat); extern void put_page_bootmem(struct page *page); #endif +void lock_memory_hotplug(void); +void unlock_memory_hotplug(void); + #else /* ! CONFIG_MEMORY_HOTPLUG */ /* * Stub functions for when hotplug is off @@ -192,6 +195,9 @@ static inline void register_page_bootmem_info_node(struct pglist_data *pgdat) { } +static inline void lock_memory_hotplug(void) {} +static inline void unlock_memory_hotplug(void) {} + #endif /* ! CONFIG_MEMORY_HOTPLUG */ #ifdef CONFIG_MEMORY_HOTREMOVE diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 1243241..46ab2c0 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -51,6 +51,7 @@ #include #include #include +#include #include "internal.h" int sysctl_memory_failure_early_kill __read_mostly = 0; @@ -1230,11 +1231,10 @@ static int get_any_page(struct page *p, unsigned long pfn, int flags) return 1; /* - * The lock_system_sleep prevents a race with memory hotplug, - * because the isolation assumes there's only a single user. + * The lock_memory_hotplug prevents a race with memory hotplug. * This is a big hammer, a better would be nicer. */ - lock_system_sleep(); + lock_memory_hotplug(); /* * Isolate the page, so that it doesn't get reallocated if it @@ -1264,7 +1264,7 @@ static int get_any_page(struct page *p, unsigned long pfn, int flags) ret = 1; } unset_migratetype_isolate(p); - unlock_system_sleep(); + unlock_memory_hotplug(); return ret; } diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 833e286..7549a01 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -34,6 +34,23 @@ #include "internal.h" +DEFINE_MUTEX(mem_hotplug_mutex); + +void lock_memory_hotplug(void) +{ + mutex_lock(&mem_hotplug_mutex); + + /* for exclusive hibernation if CONFIG_HIBERNATION=y */ + lock_system_sleep(); +} + +void unlock_memory_hotplug(void) +{ + unlock_system_sleep(); + mutex_unlock(&mem_hotplug_mutex); +} + + /* add this memory to iomem resource */ static struct resource *register_memory_resource(u64 start, u64 size) { @@ -491,7 +508,7 @@ int mem_online_node(int nid) pg_data_t *pgdat; int ret; - lock_system_sleep(); + lock_memory_hotplug(); pgdat = hotadd_new_pgdat(nid, 0); if (pgdat) { ret = -ENOMEM; @@ -502,7 +519,7 @@ int mem_online_node(int nid) BUG_ON(ret); out: - unlock_system_sleep(); + unlock_memory_hotplug(); return ret; } @@ -514,7 +531,7 @@ int __ref add_memory(int nid, u64 start, u64 size) struct resource *res; int ret; - lock_system_sleep(); + lock_memory_hotplug(); res = register_memory_resource(start, size); ret = -EEXIST; @@ -561,7 +578,7 @@ error: release_memory_resource(res); out: - unlock_system_sleep(); + unlock_memory_hotplug(); return ret; } EXPORT_SYMBOL_GPL(add_memory); @@ -789,7 +806,7 @@ static int offline_pages(unsigned long start_pfn, if (!test_pages_in_a_zone(start_pfn, end_pfn)) return -EINVAL; - lock_system_sleep(); + lock_memory_hotplug(); zone = page_zone(pfn_to_page(start_pfn)); node = zone_to_nid(zone); @@ -877,7 +894,7 @@ repeat: vm_total_pages = nr_free_pagecache_pages(); memory_notify(MEM_OFFLINE, &arg); - unlock_system_sleep(); + unlock_memory_hotplug(); return 0; failed_removal: @@ -888,7 +905,7 @@ failed_removal: undo_isolate_page_range(start_pfn, end_pfn); out: - unlock_system_sleep(); + unlock_memory_hotplug(); return ret; } -- 1.6.5.2 -- 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/