From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 76BB3600299 for ; Fri, 6 Aug 2010 01:15:36 -0400 (EDT) Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [202.81.31.245]) by e23smtp08.au.ibm.com (8.14.4/8.13.1) with ESMTP id o765FU3J025377 for ; Fri, 6 Aug 2010 15:15:30 +1000 Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o765FYSu1781996 for ; Fri, 6 Aug 2010 15:15:34 +1000 Received: from d23av02.au.ibm.com (loopback [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id o765FXbj017054 for ; Fri, 6 Aug 2010 15:15:34 +1000 From: Benjamin Herrenschmidt Subject: [PATCH 31/43] memblock: Add arch function to control coalescing of memblock memory regions Date: Fri, 6 Aug 2010 15:15:12 +1000 Message-Id: <1281071724-28740-32-git-send-email-benh@kernel.crashing.org> In-Reply-To: <1281071724-28740-1-git-send-email-benh@kernel.crashing.org> References: <1281071724-28740-1-git-send-email-benh@kernel.crashing.org> Sender: owner-linux-mm@kvack.org To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, torvalds@linux-foundation.org, Benjamin Herrenschmidt List-ID: Some archs such as ARM want to avoid coalescing accross things such as the lowmem/highmem boundary or similar. This provides the option to control it via an arch callback for which a weak default is provided which always allows coalescing. Signed-off-by: Benjamin Herrenschmidt --- include/linux/memblock.h | 2 ++ mm/memblock.c | 19 ++++++++++++++++++- 2 files changed, 20 insertions(+), 1 deletions(-) diff --git a/include/linux/memblock.h b/include/linux/memblock.h index 150be93..e5e8f9d 100644 --- a/include/linux/memblock.h +++ b/include/linux/memblock.h @@ -72,6 +72,8 @@ extern void memblock_dump_all(void); /* Provided by the architecture */ extern phys_addr_t memblock_nid_range(phys_addr_t start, phys_addr_t end, int *nid); +extern int memblock_memory_can_coalesce(phys_addr_t addr1, phys_addr_t size1, + phys_addr_t addr2, phys_addr_t size2); /** * memblock_set_current_limit - Set the current allocation limit to allow diff --git a/mm/memblock.c b/mm/memblock.c index 0787790..8715f09 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -241,6 +241,12 @@ static int memblock_double_array(struct memblock_type *type) return 0; } +extern int __weak memblock_memory_can_coalesce(phys_addr_t addr1, phys_addr_t size1, + phys_addr_t addr2, phys_addr_t size2) +{ + return 1; +} + static long memblock_add_region(struct memblock_type *type, phys_addr_t base, phys_addr_t size) { unsigned long coalesced = 0; @@ -262,6 +268,10 @@ static long memblock_add_region(struct memblock_type *type, phys_addr_t base, ph return 0; adjacent = memblock_addrs_adjacent(base, size, rgnbase, rgnsize); + /* Check if arch allows coalescing */ + if (adjacent != 0 && type == &memblock.memory && + !memblock_memory_can_coalesce(base, size, rgnbase, rgnsize)) + break; if (adjacent > 0) { type->regions[i].base -= size; type->regions[i].size += size; @@ -274,7 +284,14 @@ static long memblock_add_region(struct memblock_type *type, phys_addr_t base, ph } } - if ((i < type->cnt - 1) && memblock_regions_adjacent(type, i, i+1)) { + /* If we plugged a hole, we may want to also coalesce with the + * next region + */ + if ((i < type->cnt - 1) && memblock_regions_adjacent(type, i, i+1) && + ((type != &memblock.memory || memblock_memory_can_coalesce(type->regions[i].base, + type->regions[i].size, + type->regions[i+1].base, + type->regions[i+1].size)))) { memblock_coalesce_regions(type, i, i+1); coalesced++; } -- 1.7.0.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org