Dan Streetman 18ab4d4ced swap: change swap_list_head to plist, add swap_avail_head ... Originally get_swap_page() started iterating through the singly-linked list of swap_info_structs using swap_list.next or highest_priority_index, which both were intended to point to the highest priority active swap target that was not full. The first patch in this series changed the singly-linked list to a doubly-linked list, and removed the logic to start at the highest priority non-full entry; it starts scanning at the highest priority entry each time, even if the entry is full. Replace the manually ordered swap_list_head with a plist, swap_active_head. Add a new plist, swap_avail_head. The original swap_active_head plist contains all active swap_info_structs, as before, while the new swap_avail_head plist contains only swap_info_structs that are active and available, i.e. not full. Add a new spinlock, swap_avail_lock, to protect the swap_avail_head list. Mel Gorman suggested using plists since they internally handle ordering the list entries based on priority, which is exactly what swap was doing manually. All the ordering code is now removed, and swap_info_struct entries and simply added to their corresponding plist and automatically ordered correctly. Using a new plist for available swap_info_structs simplifies and optimizes get_swap_page(), which no longer has to iterate over full swap_info_structs. Using a new spinlock for swap_avail_head plist allows each swap_info_struct to add or remove themselves from the plist when they become full or not-full; previously they could not do so because the swap_info_struct->lock is held when they change from full<->not-full, and the swap_lock protecting the main swap_active_head must be ordered before any swap_info_struct->lock. Signed-off-by: Dan Streetman <ddstreet@ieee.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Shaohua Li <shli@fusionio.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Hugh Dickins <hughd@google.com> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Cc: Weijie Yang <weijieut@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Bob Liu <bob.liu@oracle.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2014-06-04 16:54:07 -07:00
..
backing-dev.c
balloon_compaction.c
bootmem.c
cleancache.c
compaction.c	mm/compaction: avoid rescanning pageblocks in isolate_freepages	2014-06-04 16:54:07 -07:00
debug-pagealloc.c
dmapool.c
early_ioremap.c
fadvise.c
failslab.c
filemap.c
filemap_xip.c
fremap.c
frontswap.c	swap: change swap_list_head to plist, add swap_avail_head	2014-06-04 16:54:07 -07:00
gup.c
highmem.c
huge_memory.c
hugetlb.c
hugetlb_cgroup.c
hwpoison-inject.c
init-mm.c
internal.h	mm: fold mlocked_vma_newpage() into its only call site	2014-06-04 16:54:07 -07:00
interval_tree.c
iov_iter.c
Kconfig
Kconfig.debug
kmemcheck.c
kmemleak-test.c
kmemleak.c
ksm.c
list_lru.c
maccess.c
madvise.c
Makefile
memblock.c
memcontrol.c
memory-failure.c	mm, migration: add destination page freeing callback	2014-06-04 16:54:06 -07:00
memory.c
memory_hotplug.c	mm, migration: add destination page freeing callback	2014-06-04 16:54:06 -07:00
mempolicy.c	mm, migration: add destination page freeing callback	2014-06-04 16:54:06 -07:00
mempool.c
migrate.c	mm, migration: add destination page freeing callback	2014-06-04 16:54:06 -07:00
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	mm, thp: avoid excessive compaction latency during fault	2014-06-04 16:54:06 -07:00
page_cgroup.c
page_io.c
page_isolation.c
pagewalk.c
percpu-km.c
percpu-vm.c
percpu.c
pgtable-generic.c
process_vm_access.c
quicklist.c
readahead.c
rmap.c	mm: fold mlocked_vma_newpage() into its only call site	2014-06-04 16:54:07 -07:00
shmem.c
slab.c
slab.h
slab_common.c
slob.c
slub.c
sparse-vmemmap.c
sparse.c
swap.c
swap_state.c
swapfile.c	swap: change swap_list_head to plist, add swap_avail_head	2014-06-04 16:54:07 -07:00
truncate.c
util.c
vmacache.c
vmalloc.c
vmpressure.c
vmscan.c
vmstat.c	mm: use the light version __mod_zone_page_state in mlocked_vma_newpage()	2014-06-04 16:54:07 -07:00
workingset.c
zbud.c
zsmalloc.c
zswap.c