From 81114baa835b59ed02d14aa1d67f91ea874077cd Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Mon, 9 Apr 2018 20:25:06 +0800 Subject: [PATCH] f2fs: don't use GFP_ZERO for page caches Related to https://lkml.org/lkml/2018/4/8/661 Sometimes, we need to write meta data to new allocated block address, then we will allocate a zeroed page in inner inode's address space, and fill partial data in it, and leave other place with zero value which means some fields are initial status. There are two inner inodes (meta inode and node inode) setting __GFP_ZERO, I have just checked them, for both of them, we can avoid using __GFP_ZERO, and do initialization by ourselves to avoid unneeded/redundant zeroing from mm. Cc: Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/checkpoint.c | 4 +++- fs/f2fs/inode.c | 4 ++-- fs/f2fs/segment.c | 3 +++ fs/f2fs/segment.h | 1 + 4 files changed, 9 insertions(+), 3 deletions(-) diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 3d3a1f6..8fc55d4 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -100,8 +100,10 @@ repeat: * readonly and make sure do not write checkpoint with non-uptodate * meta page. */ - if (unlikely(!PageUptodate(page))) + if (unlikely(!PageUptodate(page))) { + memset(page_address(page), 0, PAGE_SIZE); f2fs_stop_checkpoint(sbi, false); + } out: return page; } diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 417c9dc..87535bf 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -320,10 +320,10 @@ struct inode *f2fs_iget(struct super_block *sb, unsigned long ino) make_now: if (ino == F2FS_NODE_INO(sbi)) { inode->i_mapping->a_ops = &f2fs_node_aops; - mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_ZERO); + mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS); } else if (ino == F2FS_META_INO(sbi)) { inode->i_mapping->a_ops = &f2fs_meta_aops; - mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_ZERO); + mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS); } else if (S_ISREG(inode->i_mode)) { inode->i_op = &f2fs_file_inode_operations; inode->i_fop = &f2fs_file_operations; diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index a7ec952..0fb006f5 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -1979,6 +1979,7 @@ static void write_current_sum_page(struct f2fs_sb_info *sbi, struct f2fs_summary_block *dst; dst = (struct f2fs_summary_block *)page_address(page); + memset(dst, 0, PAGE_SIZE); mutex_lock(&curseg->curseg_mutex); @@ -3133,6 +3134,7 @@ static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr) page = grab_meta_page(sbi, blkaddr++); kaddr = (unsigned char *)page_address(page); + memset(kaddr, 0, PAGE_SIZE); /* Step 1: write nat cache */ seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA); @@ -3157,6 +3159,7 @@ static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr) if (!page) { page = grab_meta_page(sbi, blkaddr++); kaddr = (unsigned char *)page_address(page); + memset(kaddr, 0, PAGE_SIZE); written_size = 0; } summary = (struct f2fs_summary *)(kaddr + written_size); diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index 3325d07..492ad0c 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -375,6 +375,7 @@ static inline void seg_info_to_sit_page(struct f2fs_sb_info *sbi, int i; raw_sit = (struct f2fs_sit_block *)page_address(page); + memset(raw_sit, 0, PAGE_SIZE); for (i = 0; i < end - start; i++) { rs = &raw_sit->entries[i]; se = get_seg_entry(sbi, start + i); -- 2.7.4