linux/mm/memory_hotplug.c, branch v2.6.28

meminit section warnings

2008-11-30T18:03:35Z

Signed-off-by: Al Viro Signed-off-by: Linus Torvalds

cpuset: update top cpuset's mems after adding a node

2008-11-20T02:49:58Z

After adding a node into the machine, top cpuset's mems isn't updated. By reviewing the code, we found that the update function cpuset_track_online_nodes() was invoked after node_states[N_ONLINE] changes. It is wrong because N_ONLINE just means node has pgdat, and if node has/added memory, we use N_HIGH_MEMORY. So, We should invoke the update function after node_states[N_HIGH_MEMORY] changes, just like its commit says. This patch fixes it. And we use notifier of memory hotplug instead of direct calling of cpuset_track_online_nodes(). Signed-off-by: Miao Xie Acked-by: Yasunori Goto Cc: David Rientjes Cc: Paul Menage Signed-off-by: Linus Torvalds

memory hotplug: release memory regions in PAGES_PER_SECTION chunks

2008-10-20T15:52:32Z

During hotplug memory remove, memory regions should be released on a PAGES_PER_SECTION size chunks. This mirrors the code in add_memory where resources are requested on a PAGES_PER_SECTION size. Attempting to release the entire memory region fails because there is not a single resource for the total number of pages being removed. Instead the resources for the pages are split in PAGES_PER_SECTION size chunks as requested during memory add. Signed-off-by: Nathan Fontenot Signed-off-by: Badari Pulavarty Acked-by: Yasunori Goto Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

vmscan: move isolate_lru_page() to vmscan.c

2008-10-20T15:50:25Z

On large memory systems, the VM can spend way too much time scanning through pages that it cannot (or should not) evict from memory. Not only does it use up CPU time, but it also provokes lock contention and can leave large systems under memory presure in a catatonic state. This patch series improves VM scalability by: 1) putting filesystem backed, swap backed and unevictable pages onto their own LRUs, so the system only scans the pages that it can/should evict from memory 2) switching to two handed clock replacement for the anonymous LRUs, so the number of pages that need to be scanned when the system starts swapping is bound to a reasonable number 3) keeping unevictable pages off the LRU completely, so the VM does not waste CPU time scanning them. ramfs, ramdisk, SHM_LOCKED shared memory segments and mlock()ed VMA pages are keept on the unevictable list. This patch: isolate_lru_page logically belongs to be in vmscan.c than migrate.c. It is tough, because we don't need that function without memory migration so there is a valid argument to have it in migrate.c. However a subsequent patch needs to make use of it in the core mm, so we can happily move it to vmscan.c. Also, make the function a little more generic by not requiring that it adds an isolated page to a given list. Callers can do that. Note that we now have '__isolate_lru_page()', that does something quite different, visible outside of vmscan.c for use with memory controller. Methinks we need to rationalize these names/purposes. --lts [akpm@linux-foundation.org: fix mm/memory_hotplug.c build] Signed-off-by: Nick Piggin Signed-off-by: Rik van Riel Signed-off-by: Lee Schermerhorn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: cleanup to make remove_memory() arch-neutral

2008-10-20T15:50:25Z

There is nothing architecture specific about remove_memory(). remove_memory() function is common for all architectures which support hotplug memory remove. Instead of duplicating it in every architecture, collapse them into arch neutral function. [akpm@linux-foundation.org: fix the export] Signed-off-by: Badari Pulavarty Cc: Yasunori Goto Cc: Gary Hade Cc: Mel Gorman Cc: Yasunori Goto Cc: "Luck, Tony" Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Heiko Carstens Cc: Martin Schwidefsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

memory-hotplug: add sysfs removable attribute for hotplug memory remove

2008-07-24T17:47:21Z

Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty Signed-off-by: Mel Gorman Acked-by: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

memory-hotplug: don't calculate vm_total_pages twice when rebuilding zonelists in online_pages()

2008-07-24T17:47:21Z

If zonelist is required to be rebuilt in online_pages(), there is no need to recalculate vm_total_pages in that function, as it has been updated in the call build_all_zonelists(). Signed-off-by: Kent Liu Acked-by: KAMEZAWA Hiroyuki Cc: Yasunori Goto Cc: Andy Whitcroft Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

memory hotplug: small fixes to bootmem freeing for memory hotremove

2008-07-24T17:47:21Z

- Change some naming * Magic -> types * MIX_INFO -> MIX_SECTION_INFO * Change definition of bootmem type from direct hex value - __free_pages_bootmem() becomes __meminit. Signed-off-by: Yasunori Goto Cc: Andy Whitcroft Cc: Badari Pulavarty Cc: Yinghai Lu Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: make register_page_bootmem_info_section() static

2008-07-24T17:47:21Z

Make the needlessly global register_page_bootmem_info_section() static. Signed-off-by: Adrian Bunk Acked-by: Yasunori Goto Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: drop unneeded pgdat argument from free_area_init_node()

2008-07-24T17:47:16Z

free_area_init_node() gets passed in the node id as well as the node descriptor. This is redundant as the function can trivially get the node descriptor itself by means of NODE_DATA() and the node's id. I checked all the users and NODE_DATA() seems to be usable everywhere from where this function is called. Signed-off-by: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds