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| author | Jiang Liu <liuj97@gmail.com> | 2013-06-07 00:07:30 +0800 |
|---|---|---|
| committer | Chanho Park <chanho61.park@samsung.com> | 2014-03-20 17:44:24 +0900 |
| commit | 75c26bd23b5fd24b093a81578a098d487f844777 (patch) | |
| tree | b7962658dc76b337598a80aed08dca469802044d /drivers | |
| parent | 6482fe5cf7b33b53b435556d3c368f69cf11a296 (diff) | |
| download | linux-3.10-75c26bd23b5fd24b093a81578a098d487f844777.tar.gz linux-3.10-75c26bd23b5fd24b093a81578a098d487f844777.tar.bz2 linux-3.10-75c26bd23b5fd24b093a81578a098d487f844777.zip | |
zram: optimize memory operations with clear_page()/copy_page()
Some architectures provides architecture-specific, optimized version of
clear_page()/copy_page(), which may have better performance than
memset()/memcpy(). So use clear_page()/copy_page() to optimize zram
performance if possible.
Change-Id: If33e01891f1bc3790144f85c02e0869a02d0faae
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/staging/zram/zram_drv.c | 27 |
1 files changed, 16 insertions, 11 deletions
diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c index 49f34b06518..18a89863ae5 100644 --- a/drivers/staging/zram/zram_drv.c +++ b/drivers/staging/zram/zram_drv.c @@ -128,23 +128,26 @@ static void zram_free_page(struct zram *zram, size_t index) meta->table[index].size = 0; } +static inline int is_partial_io(struct bio_vec *bvec) +{ + return bvec->bv_len != PAGE_SIZE; +} + static void handle_zero_page(struct bio_vec *bvec) { struct page *page = bvec->bv_page; void *user_mem; user_mem = kmap_atomic(page); - memset(user_mem + bvec->bv_offset, 0, bvec->bv_len); + if (is_partial_io(bvec)) + memset(user_mem + bvec->bv_offset, 0, bvec->bv_len); + else + clear_page(user_mem); kunmap_atomic(user_mem); flush_dcache_page(page); } -static inline int is_partial_io(struct bio_vec *bvec) -{ - return bvec->bv_len != PAGE_SIZE; -} - static int zram_decompress_page(struct zram *zram, char *mem, u32 index) { int ret = LZO_E_OK; @@ -154,13 +157,13 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index) unsigned long handle = meta->table[index].handle; if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) { - memset(mem, 0, PAGE_SIZE); + clear_page(mem); return 0; } cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO); if (meta->table[index].size == PAGE_SIZE) - memcpy(mem, cmem, PAGE_SIZE); + copy_page(mem, cmem); else ret = lzo1x_decompress_safe(cmem, meta->table[index].size, mem, &clen); @@ -309,11 +312,13 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, } cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_WO); - if ((clen == PAGE_SIZE) && !is_partial_io(bvec)) + if ((clen == PAGE_SIZE) && !is_partial_io(bvec)) { src = kmap_atomic(page); - memcpy(cmem, src, clen); - if ((clen == PAGE_SIZE) && !is_partial_io(bvec)) + copy_page(cmem, src); kunmap_atomic(src); + } else { + memcpy(cmem, src, clen); + } zs_unmap_object(meta->mem_pool, handle); |