BMC/Intel-BMC/linux.git/mm/zsmalloc.c, branch dev

zpool: remove zpool_evict()

2015-06-26T00:00:37+00:00

Remove zpool_evict() helper function. As zbud is currently the only zpool implementation that supports eviction, add zpool and zpool_ops references to struct zbud_pool and directly call zpool_ops->evict(zpool, handle) on eviction. Currently zpool provides the zpool_evict helper which locks the zpool list lock and searches through all pools to find the specific one matching the caller, and call the corresponding zpool_ops->evict function. However, this is unnecessary, as the zbud pool can simply keep a reference to the zpool that created it, as well as the zpool_ops, and directly call the zpool_ops->evict function, when it needs to evict a page. This avoids a spinlock and list search in zpool for each eviction. Signed-off-by: Dan Streetman Cc: Seth Jennings Cc: Minchan Kim Cc: Nitin Gupta Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

zsmalloc: remove obsolete ZSMALLOC_DEBUG

2015-06-26T00:00:35+00:00

The DEBUG define in zsmalloc is useless, there is no usage of it at all. Signed-off-by: Marcin Jabrzyk Acked-by: Sergey Senozhatsky Cc: Minchan Kim Cc: Nitin Gupta Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

zsmalloc: fix a null pointer dereference in destroy_handle_cache()

2015-06-10T23:43:43+00:00

If zs_create_pool()->create_handle_cache()->kmem_cache_create() or pool->name allocation fails, zs_create_pool()->destroy_handle_cache() will dereference the NULL pool->handle_cachep. Modify destroy_handle_cache() to avoid this. Signed-off-by: Sergey Senozhatsky Cc: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

zsmalloc: remove extra cond_resched() in __zs_compact

2015-04-15T23:35:22+00:00

Do not perform cond_resched() before the busy compaction loop in __zs_compact(), because this loop does it when needed. Signed-off-by: Sergey Senozhatsky Acked-by: Minchan Kim Cc: Nitin Gupta Cc: Stephen Rothwell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

zsmalloc: fix fatal corruption due to wrong size class selection

2015-04-15T23:35:22+00:00

There is no point in overriding the size class below. It causes fatal corruption on the next chunk on the 3264-bytes size class, which is the last size class that is not huge. For example, if the requested size was exactly 3264 bytes, current zsmalloc allocates and returns a chunk from the size class of 3264 bytes, not 4096. User access to this chunk may overwrite head of the next adjacent chunk. Here is the panic log captured when freelist was corrupted due to this: Kernel BUG at ffffffc00030659c [verbose debug info unavailable] Internal error: Oops - BUG: 96000006 [#1] PREEMPT SMP Modules linked in: exynos-snapshot: core register saved(CPU:5) CPUMERRSR: 0000000000000000, L2MERRSR: 0000000000000000 exynos-snapshot: context saved(CPU:5) exynos-snapshot: item - log_kevents is disabled CPU: 5 PID: 898 Comm: kswapd0 Not tainted 3.10.61-4497415-eng #1 task: ffffffc0b8783d80 ti: ffffffc0b71e8000 task.ti: ffffffc0b71e8000 PC is at obj_idx_to_offset+0x0/0x1c LR is at obj_malloc+0x44/0xe8 pc : [] lr : [] pstate: a0000045 sp : ffffffc0b71eb790 x29: ffffffc0b71eb790 x28: ffffffc00204c000 x27: 000000000001d96f x26: 0000000000000000 x25: ffffffc098cc3500 x24: ffffffc0a13f2810 x23: ffffffc098cc3501 x22: ffffffc0a13f2800 x21: 000011e1a02006e3 x20: ffffffc0a13f2800 x19: ffffffbc02a7e000 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000feb x15: 0000000000000000 x14: 00000000a01003e3 x13: 0000000000000020 x12: fffffffffffffff0 x11: ffffffc08b264000 x10: 00000000e3a01004 x9 : ffffffc08b263fea x8 : ffffffc0b1e611c0 x7 : ffffffc000307d24 x6 : 0000000000000000 x5 : 0000000000000038 x4 : 000000000000011e x3 : ffffffbc00003e90 x2 : 0000000000000cc0 x1 : 00000000d0100371 x0 : ffffffbc00003e90 Reported-by: Sooyong Suk Signed-off-by: Heesub Shin Tested-by: Sooyong Suk Acked-by: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

zsmalloc: remove unnecessary insertion/removal of zspage in compaction

2015-04-15T23:35:22+00:00

In putback_zspage, we don't need to insert a zspage into list of zspage in size_class again to just fix fullness group. We could do directly without reinsertion so we could save some instuctions. Reported-by: Heesub Shin Signed-off-by: Minchan Kim Cc: Nitin Gupta Cc: Sergey Senozhatsky Cc: Dan Streetman Cc: Seth Jennings Cc: Ganesh Mahendran Cc: Luigi Semenzato Cc: Gunho Lee Cc: Juneho Choi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

zsmalloc: micro-optimize zs_object_copy()

2015-04-15T23:35:22+00:00

A micro-optimization. Avoid additional branching and reduce (a bit) registry pressure (f.e. s_off += size; d_off += size; may be calculated twise: first for >= PAGE_SIZE check and later for offset update in "else" clause). scripts/bloat-o-meter shows some improvement add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-10 (-10) function old new delta zs_object_copy 550 540 -10 Signed-off-by: Sergey Senozhatsky Acked-by: Minchan Kim Cc: Nitin Gupta Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

zsmalloc: remove synchronize_rcu from zs_compact()

2015-04-15T23:35:21+00:00

Do not synchronize rcu in zs_compact(). Neither zsmalloc not zram use rcu. Signed-off-by: Sergey Senozhatsky Acked-by: Minchan Kim Cc: Nitin Gupta Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/zsmalloc.c: fix comment for get_pages_per_zspage

2015-04-15T23:35:21+00:00

Signed-off-by: Yinghao Xie Suggested-by: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

zsmalloc: zsmalloc documentation

2015-04-15T23:35:21+00:00

Create zsmalloc doc which explains design concept and stat information. Signed-off-by: Minchan Kim Cc: Juneho Choi Cc: Gunho Lee Cc: Luigi Semenzato Cc: Dan Streetman Cc: Seth Jennings Cc: Nitin Gupta Cc: Jerome Marchand Cc: Sergey Senozhatsky Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds