6922c0c7ab
Convert shmem_writepage() to use shmem_delete_from_page_cache() to use shmem_radix_tree_replace() to substitute swap entry for page pointer atomically in the radix tree. As with shmem_add_to_page_cache(), it's not entirely satisfactory to be copying such code from delete_from_swap_cache, but again judged easier to sell than making its other callers go through the extras. Remove the toy implementation's shmem_put_swap() and shmem_get_swap(), now unreferenced, and the hack to disable swap: it's now good to go. The way things have worked out, info->lock no longer helps to guard the shmem_swaplist: we increment swapped under shmem_swaplist_mutex only. That global mutex exclusion between shmem_writepage() and shmem_unuse() is not pretty, and we ought to find another way; but it's been forced on us by recent race discoveries, not a consequence of this patchset. And what has become of the WARN_ON_ONCE(1) free_swap_and_cache() if a swap entry was found already present? That's no longer possible, the (unknown) one inserting this page into filecache would hit the swap entry occupying that slot. Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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.. | ||
backing-dev.c | ||
bootmem.c | ||
bounce.c | ||
cleancache.c | ||
compaction.c | ||
debug-pagealloc.c | ||
dmapool.c | ||
fadvise.c | ||
failslab.c | ||
filemap.c | ||
filemap_xip.c | ||
fremap.c | ||
highmem.c | ||
huge_memory.c | ||
hugetlb.c | ||
hwpoison-inject.c | ||
init-mm.c | ||
internal.h | ||
Kconfig | ||
Kconfig.debug | ||
kmemcheck.c | ||
kmemleak-test.c | ||
kmemleak.c | ||
ksm.c | ||
maccess.c | ||
madvise.c | ||
Makefile | ||
memblock.c | ||
memcontrol.c | ||
memory-failure.c | ||
memory.c | ||
memory_hotplug.c | ||
mempolicy.c | ||
mempool.c | ||
migrate.c | ||
mincore.c | ||
mlock.c | ||
mm_init.c | ||
mmap.c | ||
mmu_context.c | ||
mmu_notifier.c | ||
mmzone.c | ||
mprotect.c | ||
mremap.c | ||
msync.c | ||
nobootmem.c | ||
nommu.c | ||
oom_kill.c | ||
page-writeback.c | ||
page_alloc.c | ||
page_cgroup.c | ||
page_io.c | ||
page_isolation.c | ||
pagewalk.c | ||
percpu-km.c | ||
percpu-vm.c | ||
percpu.c | ||
pgtable-generic.c | ||
prio_tree.c | ||
quicklist.c | ||
readahead.c | ||
rmap.c | ||
shmem.c | ||
slab.c | ||
slob.c | ||
slub.c | ||
sparse-vmemmap.c | ||
sparse.c | ||
swap.c | ||
swap_state.c | ||
swapfile.c | ||
thrash.c | ||
truncate.c | ||
util.c | ||
vmalloc.c | ||
vmscan.c | ||
vmstat.c |