From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [119.145.14.64]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 0AD101A020C for ; Mon, 21 Jul 2014 13:56:53 +1000 (EST) From: Wang Nan To: Ingo Molnar , Yinghai Lu , "Mel Gorman" , Andrew Morton , "Dave Hansen" , Zhang Yanfei Subject: [PATCH v2 1/7] memory-hotplug: add zone_for_memory() for selecting zone for new memory Date: Mon, 21 Jul 2014 11:46:36 +0800 Message-ID: <1405914402-66212-2-git-send-email-wangnan0@huawei.com> In-Reply-To: <1405914402-66212-1-git-send-email-wangnan0@huawei.com> References: <1405914402-66212-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain Cc: wangnan0@huawei.com, linux-ia64@vger.kernel.org, peifeiyue@huawei.com, linux-sh@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , This patch introduces a zone_for_memory function in arch independent code for arch_add_memory() using. Many arch_add_memory() function simply selects ZONE_HIGHMEM or ZONE_NORMAL and add new memory into it. However, with the existance of ZONE_MOVABLE, the selection method should be carefully considered: if new, higher memory is added after ZONE_MOVABLE is setup, the default zone and ZONE_MOVABLE may overlap each other. should_add_memory_movable() checks the status of ZONE_MOVABLE. If it has already contain memory, compare the address of new memory and movable memory. If new memory is higher than movable, it should be added into ZONE_MOVABLE instead of default zone. Signed-off-by: Wang Nan Cc: Zhang Yanfei Cc: Dave Hansen --- include/linux/memory_hotplug.h | 1 + mm/memory_hotplug.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 29 insertions(+) diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 010d125..3de3d02 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -258,6 +258,7 @@ static inline void remove_memory(int nid, u64 start, u64 size) {} extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn, void *arg, int (*func)(struct memory_block *, void *)); extern int add_memory(int nid, u64 start, u64 size); +extern int zone_for_memory(int nid, u64 start, u64 size, int zone_default); extern int arch_add_memory(int nid, u64 start, u64 size); extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages); extern bool is_memblock_offlined(struct memory_block *mem); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 469bbf5..348fda7 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1156,6 +1156,34 @@ static int check_hotplug_memory_range(u64 start, u64 size) return 0; } +/* + * If movable zone has already been setup, newly added memory should be check. + * If its address is higher than movable zone, it should be added as movable. + * Without this check, movable zone may overlap with other zone. + */ +static int should_add_memory_movable(int nid, u64 start, u64 size) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + pg_data_t *pgdat = NODE_DATA(nid); + struct zone *movable_zone = pgdat->node_zones + ZONE_MOVABLE; + + if (zone_is_empty(movable_zone)) + return 0; + + if (movable_zone->zone_start_pfn <= start_pfn) + return 1; + + return 0; +} + +int zone_for_memory(int nid, u64 start, u64 size, int zone_default) +{ + if (should_add_memory_movable(nid, start, size)) + return ZONE_MOVABLE; + + return zone_default; +} + /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ int __ref add_memory(int nid, u64 start, u64 size) { -- 1.8.4