Lee Schermerhorn 304dbdb7a4 [PATCH] add migratepage address space op to shmem ... Basic problem: pages of a shared memory segment can only be migrated once. In 2.6.16 through 2.6.17-rc1, shared memory mappings do not have a migratepage address space op. Therefore, migrate_pages() falls back to default processing. In this path, it will try to pageout() dirty pages. Once a shared memory page has been migrated it becomes dirty, so migrate_pages() will try to page it out. However, because the page count is 3 [cache + current + pte], pageout() will return PAGE_KEEP because is_page_cache_freeable() returns false. This will abort all subsequent migrations. This patch adds a migratepage address space op to shared memory segments to avoid taking the default path. We use the "migrate_page()" function because it knows how to migrate dirty pages. This allows shared memory segment pages to migrate, subject to other conditions such as # pte's referencing the page [page_mapcount(page)], when requested. I think this is safe. If we're migrating a shared memory page, then we found the page via a page table, so it must be in memory. Can be verified with memtoy and the shmem-mbind-test script, both available at: http://free.linux.hp.com/~lts/Tools/ Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com> Acked-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>		2006-04-22 09:19:52 -07:00
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bootmem.c
fadvise.c
filemap_xip.c
filemap.c
filemap.h
fremap.c
highmem.c
hugetlb.c
internal.h
Kconfig
madvise.c
Makefile
memory_hotplug.c
memory.c
mempolicy.c	[PATCH] Remove cond_resched in gather_stats()	2006-04-20 07:54:03 -07:00
mempool.c
migrate.c
mincore.c
mlock.c
mmap.c
mmzone.c
mprotect.c
mremap.c
msync.c
nommu.c
oom_kill.c	[PATCH] mm: fix mm_struct reference counting bugs in mm/oom_kill.c	2006-04-19 09:13:50 -07:00
page_alloc.c	[PATCH] page_alloc.c: buddy handling cleanup	2006-04-19 09:13:50 -07:00
page_io.c
page-writeback.c
pdflush.c
prio_tree.c
readahead.c
rmap.c
shmem.c	[PATCH] add migratepage address space op to shmem	2006-04-22 09:19:52 -07:00
slab.c
slob.c
sparse.c
swap_state.c
swap.c
swapfile.c
thrash.c
tiny-shmem.c
truncate.c
util.c
vmalloc.c
vmscan.c