From 6fcaebac66673926aca27c4cd99dff28c067c130 Mon Sep 17 00:00:00 2001 From: Daeho Jeong Date: Wed, 12 Aug 2020 14:17:11 +0900 Subject: f2fs: change virtual mapping way for compression pages By profiling f2fs compression works, I've found vmap() callings have unexpected hikes in the execution time in our test environment and those are bottlenecks of f2fs decompression path. Changing these with vm_map_ram(), we can enhance f2fs decompression speed pretty much. [Verification] Android Pixel 3(ARM64, 6GB RAM, 128GB UFS) Turned on only 0-3 little cores(at 1.785GHz) dd if=/dev/zero of=dummy bs=1m count=1000 echo 3 > /proc/sys/vm/drop_caches dd if=dummy of=/dev/zero bs=512k - w/o compression - 1048576000 bytes (0.9 G) copied, 2.082554 s, 480 M/s 1048576000 bytes (0.9 G) copied, 2.081634 s, 480 M/s 1048576000 bytes (0.9 G) copied, 2.090861 s, 478 M/s - before patch - 1048576000 bytes (0.9 G) copied, 7.407527 s, 135 M/s 1048576000 bytes (0.9 G) copied, 7.283734 s, 137 M/s 1048576000 bytes (0.9 G) copied, 7.291508 s, 137 M/s - after patch - 1048576000 bytes (0.9 G) copied, 1.998959 s, 500 M/s 1048576000 bytes (0.9 G) copied, 1.987554 s, 503 M/s 1048576000 bytes (0.9 G) copied, 1.986380 s, 503 M/s Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/compress.c | 36 ++++++++++++++++++++++++++---------- 1 file changed, 26 insertions(+), 10 deletions(-) (limited to 'fs/f2fs') diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c index 5949372700ee..7895186cc765 100644 --- a/fs/f2fs/compress.c +++ b/fs/f2fs/compress.c @@ -555,6 +555,22 @@ static void f2fs_compress_free_page(struct page *page) mempool_free(page, compress_page_pool); } +#define MAX_VMAP_RETRIES 3 + +static void *f2fs_vmap(struct page **pages, unsigned int count) +{ + int i; + void *buf = NULL; + + for (i = 0; i < MAX_VMAP_RETRIES; i++) { + buf = vm_map_ram(pages, count, -1); + if (buf) + break; + vm_unmap_aliases(); + } + return buf; +} + static int f2fs_compress_pages(struct compress_ctx *cc) { struct f2fs_sb_info *sbi = F2FS_I_SB(cc->inode); @@ -591,13 +607,13 @@ static int f2fs_compress_pages(struct compress_ctx *cc) } } - cc->rbuf = vmap(cc->rpages, cc->cluster_size, VM_MAP, PAGE_KERNEL_RO); + cc->rbuf = f2fs_vmap(cc->rpages, cc->cluster_size); if (!cc->rbuf) { ret = -ENOMEM; goto out_free_cpages; } - cc->cbuf = vmap(cc->cpages, cc->nr_cpages, VM_MAP, PAGE_KERNEL); + cc->cbuf = f2fs_vmap(cc->cpages, cc->nr_cpages); if (!cc->cbuf) { ret = -ENOMEM; goto out_vunmap_rbuf; @@ -625,8 +641,8 @@ static int f2fs_compress_pages(struct compress_ctx *cc) memset(&cc->cbuf->cdata[cc->clen], 0, (nr_cpages * PAGE_SIZE) - (cc->clen + COMPRESS_HEADER_SIZE)); - vunmap(cc->cbuf); - vunmap(cc->rbuf); + vm_unmap_ram(cc->cbuf, cc->nr_cpages); + vm_unmap_ram(cc->rbuf, cc->cluster_size); for (i = nr_cpages; i < cc->nr_cpages; i++) { f2fs_compress_free_page(cc->cpages[i]); @@ -643,9 +659,9 @@ static int f2fs_compress_pages(struct compress_ctx *cc) return 0; out_vunmap_cbuf: - vunmap(cc->cbuf); + vm_unmap_ram(cc->cbuf, cc->nr_cpages); out_vunmap_rbuf: - vunmap(cc->rbuf); + vm_unmap_ram(cc->rbuf, cc->cluster_size); out_free_cpages: for (i = 0; i < cc->nr_cpages; i++) { if (cc->cpages[i]) @@ -716,13 +732,13 @@ void f2fs_decompress_pages(struct bio *bio, struct page *page, bool verity) goto out_free_dic; } - dic->rbuf = vmap(dic->tpages, dic->cluster_size, VM_MAP, PAGE_KERNEL); + dic->rbuf = f2fs_vmap(dic->tpages, dic->cluster_size); if (!dic->rbuf) { ret = -ENOMEM; goto destroy_decompress_ctx; } - dic->cbuf = vmap(dic->cpages, dic->nr_cpages, VM_MAP, PAGE_KERNEL_RO); + dic->cbuf = f2fs_vmap(dic->cpages, dic->nr_cpages); if (!dic->cbuf) { ret = -ENOMEM; goto out_vunmap_rbuf; @@ -739,9 +755,9 @@ void f2fs_decompress_pages(struct bio *bio, struct page *page, bool verity) ret = cops->decompress_pages(dic); out_vunmap_cbuf: - vunmap(dic->cbuf); + vm_unmap_ram(dic->cbuf, dic->nr_cpages); out_vunmap_rbuf: - vunmap(dic->rbuf); + vm_unmap_ram(dic->rbuf, dic->cluster_size); destroy_decompress_ctx: if (cops->destroy_decompress_ctx) cops->destroy_decompress_ctx(dic); -- cgit v1.2.3