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| author | Vivek Haldar <haldar@google.com> | 2011-05-23 05:24:16 +0400 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2011-05-23 05:24:16 +0400 |
| commit | 77f4135f2a219a2127be6cc1208c42e6175b11dd (patch) | |
| tree | 8f85549d2354c5a69a5b29197f68a554daad1324 /fs/ext4 | |
| parent | 93917411be8db5d21abf15c781dfa43c5cc6edf2 (diff) | |
| download | linux-77f4135f2a219a2127be6cc1208c42e6175b11dd.tar.xz | |
ext4: count hits/misses of extent cache and expose in sysfs
The number of hits and misses for each filesystem is exposed in
/sys/fs/ext4/<dev>/extent_cache_{hits, misses}.
Tested: fsstress, manual checks.
Signed-off-by: Vivek Haldar <haldar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Diffstat (limited to 'fs/ext4')
| -rw-r--r-- | fs/ext4/ext4.h | 3 | ||||
| -rw-r--r-- | fs/ext4/extents.c | 7 | ||||
| -rw-r--r-- | fs/ext4/super.c | 16 |
3 files changed, 25 insertions, 1 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 6ce3c7c8574c..65fe1dc0c750 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1144,6 +1144,9 @@ struct ext4_sb_info { unsigned long s_ext_blocks; unsigned long s_ext_extents; #endif + /* ext4 extent cache stats */ + unsigned long extent_cache_hits; + unsigned long extent_cache_misses; /* for buddy allocator */ struct ext4_group_info ***s_group_info; diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 9a3844adb1cb..4444317d141a 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2035,6 +2035,7 @@ ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block, struct ext4_extent *ex) { struct ext4_ext_cache *cex; + struct ext4_sb_info *sbi; int ret = 0; /* @@ -2042,6 +2043,7 @@ ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block, */ spin_lock(&EXT4_I(inode)->i_block_reservation_lock); cex = &EXT4_I(inode)->i_cached_extent; + sbi = EXT4_SB(inode->i_sb); /* has cache valid data? */ if (cex->ec_len == 0) @@ -2057,6 +2059,10 @@ ext4_ext_in_cache(struct inode *inode, ext4_lblk_t block, ret = 1; } errout: + if (!ret) + sbi->extent_cache_misses++; + else + sbi->extent_cache_hits++; spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); return ret; } @@ -3901,4 +3907,3 @@ int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, return error; } - diff --git a/fs/ext4/super.c b/fs/ext4/super.c index fdce4eebce0c..874dd25b7481 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2439,6 +2439,18 @@ static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a, EXT4_SB(sb)->s_sectors_written_start) >> 1))); } +static ssize_t extent_cache_hits_show(struct ext4_attr *a, + struct ext4_sb_info *sbi, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%lu\n", sbi->extent_cache_hits); +} + +static ssize_t extent_cache_misses_show(struct ext4_attr *a, + struct ext4_sb_info *sbi, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%lu\n", sbi->extent_cache_misses); +} + static ssize_t inode_readahead_blks_store(struct ext4_attr *a, struct ext4_sb_info *sbi, const char *buf, size_t count) @@ -2496,6 +2508,8 @@ static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store) EXT4_RO_ATTR(delayed_allocation_blocks); EXT4_RO_ATTR(session_write_kbytes); EXT4_RO_ATTR(lifetime_write_kbytes); +EXT4_RO_ATTR(extent_cache_hits); +EXT4_RO_ATTR(extent_cache_misses); EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show, inode_readahead_blks_store, s_inode_readahead_blks); EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal); @@ -2511,6 +2525,8 @@ static struct attribute *ext4_attrs[] = { ATTR_LIST(delayed_allocation_blocks), ATTR_LIST(session_write_kbytes), ATTR_LIST(lifetime_write_kbytes), + ATTR_LIST(extent_cache_hits), + ATTR_LIST(extent_cache_misses), ATTR_LIST(inode_readahead_blks), ATTR_LIST(inode_goal), ATTR_LIST(mb_stats), |