From ec08c14ba28ce073b3f63c8edbee0f3c38e1b6a1 Mon Sep 17 00:00:00 2001 From: Dave Chinner <dchinner@redhat.com> Date: Mon, 22 Mar 2021 09:52:05 -0700 Subject: [PATCH] xfs: type verification is expensive From a concurrent rm -rf workload: 41.04% [kernel] [k] xfs_dir3_leaf_check_int 9.85% [kernel] [k] __xfs_dir3_data_check 5.60% [kernel] [k] xfs_verify_ino 5.32% [kernel] [k] xfs_agino_range 4.21% [kernel] [k] memcpy 3.06% [kernel] [k] xfs_errortag_test 2.57% [kernel] [k] xfs_dir_ino_validate 1.66% [kernel] [k] xfs_dir2_data_get_ftype 1.17% [kernel] [k] do_raw_spin_lock 1.11% [kernel] [k] xfs_verify_dir_ino 0.84% [kernel] [k] __raw_callee_save___pv_queued_spin_unlock 0.83% [kernel] [k] xfs_buf_find 0.64% [kernel] [k] xfs_log_commit_cil THere's an awful lot of overhead in just range checking inode numbers in that, but each inode number check is not a lot of code. The total is a bit over 14.5% of the CPU time is spent validating inode numbers. The problem is that they deeply nested global scope functions so the overhead here is all in function call marshalling. text data bss dec hex filename 2077 0 0 2077 81d fs/xfs/libxfs/xfs_types.o.orig 2197 0 0 2197 895 fs/xfs/libxfs/xfs_types.o There's a small increase in binary size by inlining all the local nested calls in the verifier functions, but the same workload now profiles as: 40.69% [kernel] [k] xfs_dir3_leaf_check_int 10.52% [kernel] [k] __xfs_dir3_data_check 6.68% [kernel] [k] xfs_verify_dir_ino 4.22% [kernel] [k] xfs_errortag_test 4.15% [kernel] [k] memcpy 3.53% [kernel] [k] xfs_dir_ino_validate 1.87% [kernel] [k] xfs_dir2_data_get_ftype 1.37% [kernel] [k] do_raw_spin_lock 0.98% [kernel] [k] xfs_buf_find 0.94% [kernel] [k] __raw_callee_save___pv_queued_spin_unlock 0.73% [kernel] [k] xfs_log_commit_cil Now we only spend just over 10% of the time validing inode numbers for the same workload. Hence a few "inline" keyworks is good enough to reduce the validation overhead by 30%... Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Darrick J. Wong <djwong@kernel.org> --- fs/xfs/libxfs/xfs_types.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/fs/xfs/libxfs/xfs_types.c b/fs/xfs/libxfs/xfs_types.c index b254fbeaaa501..04801362e1a73 100644 --- a/fs/xfs/libxfs/xfs_types.c +++ b/fs/xfs/libxfs/xfs_types.c @@ -13,7 +13,7 @@ #include "xfs_mount.h" /* Find the size of the AG, in blocks. */ -xfs_agblock_t +inline xfs_agblock_t xfs_ag_block_count( struct xfs_mount *mp, xfs_agnumber_t agno) @@ -29,7 +29,7 @@ xfs_ag_block_count( * Verify that an AG block number pointer neither points outside the AG * nor points at static metadata. */ -bool +inline bool xfs_verify_agbno( struct xfs_mount *mp, xfs_agnumber_t agno, @@ -49,7 +49,7 @@ xfs_verify_agbno( * Verify that an FS block number pointer neither points outside the * filesystem nor points at static AG metadata. */ -bool +inline bool xfs_verify_fsbno( struct xfs_mount *mp, xfs_fsblock_t fsbno) @@ -85,7 +85,7 @@ xfs_verify_fsbext( } /* Calculate the first and last possible inode number in an AG. */ -void +inline void xfs_agino_range( struct xfs_mount *mp, xfs_agnumber_t agno, @@ -116,7 +116,7 @@ xfs_agino_range( * Verify that an AG inode number pointer neither points outside the AG * nor points at static metadata. */ -bool +inline bool xfs_verify_agino( struct xfs_mount *mp, xfs_agnumber_t agno, @@ -146,7 +146,7 @@ xfs_verify_agino_or_null( * Verify that an FS inode number pointer neither points outside the * filesystem nor points at static AG metadata. */ -bool +inline bool xfs_verify_ino( struct xfs_mount *mp, xfs_ino_t ino) @@ -162,7 +162,7 @@ xfs_verify_ino( } /* Is this an internal inode number? */ -bool +inline bool xfs_internal_inum( struct xfs_mount *mp, xfs_ino_t ino) @@ -190,7 +190,7 @@ xfs_verify_dir_ino( * Verify that an realtime block number pointer doesn't point off the * end of the realtime device. */ -bool +inline bool xfs_verify_rtbno( struct xfs_mount *mp, xfs_rtblock_t rtbno) @@ -215,7 +215,7 @@ xfs_verify_rtext( } /* Calculate the range of valid icount values. */ -void +inline void xfs_icount_range( struct xfs_mount *mp, unsigned long long *min,