From 446400346d2dcec222abebf0db1b0ad61f013548 Mon Sep 17 00:00:00 2001 From: Mateusz Guzik Date: Thu, 15 Oct 2020 05:45:28 +0000 Subject: [PATCH] Add branch prediction to ZFS_ENTER and ZFS_VERIFY_ZP macros They are expected to fail only in corner cases. Reviewed-by: Ryan Moeller Reviewed-by: Brian Behlendorf Reviewed-by: Matt Macy Signed-off-by: Mateusz Guzik Closes #11153 --- include/os/freebsd/zfs/sys/zfs_znode_impl.h | 4 ++-- include/os/linux/zfs/sys/zfs_znode_impl.h | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/include/os/freebsd/zfs/sys/zfs_znode_impl.h b/include/os/freebsd/zfs/sys/zfs_znode_impl.h index 186afa9b2..7a60eb58b 100644 --- a/include/os/freebsd/zfs/sys/zfs_znode_impl.h +++ b/include/os/freebsd/zfs/sys/zfs_znode_impl.h @@ -125,7 +125,7 @@ extern minor_t zfsdev_minor_alloc(void); #define ZFS_ENTER(zfsvfs) \ { \ rrm_enter_read(&(zfsvfs)->z_teardown_lock, FTAG); \ - if ((zfsvfs)->z_unmounted) { \ + if (__predict_false((zfsvfs)->z_unmounted)) { \ ZFS_EXIT(zfsvfs); \ return (EIO); \ } \ @@ -136,7 +136,7 @@ extern minor_t zfsdev_minor_alloc(void); /* Verifies the znode is valid */ #define ZFS_VERIFY_ZP(zp) \ - if ((zp)->z_sa_hdl == NULL) { \ + if (__predict_false((zp)->z_sa_hdl == NULL)) { \ ZFS_EXIT((zp)->z_zfsvfs); \ return (EIO); \ } \ diff --git a/include/os/linux/zfs/sys/zfs_znode_impl.h b/include/os/linux/zfs/sys/zfs_znode_impl.h index b1a91f666..bcd721435 100644 --- a/include/os/linux/zfs/sys/zfs_znode_impl.h +++ b/include/os/linux/zfs/sys/zfs_znode_impl.h @@ -80,7 +80,7 @@ extern "C" { #define ZFS_ENTER_ERROR(zfsvfs, error) \ do { \ rrm_enter_read(&(zfsvfs)->z_teardown_lock, FTAG); \ - if ((zfsvfs)->z_unmounted) { \ + if (unlikely((zfsvfs)->z_unmounted)) { \ ZFS_EXIT(zfsvfs); \ return (error); \ } \ @@ -103,7 +103,7 @@ do { \ /* Verifies the znode is valid. */ #define ZFS_VERIFY_ZP_ERROR(zp, error) \ do { \ - if ((zp)->z_sa_hdl == NULL) { \ + if (unlikely((zp)->z_sa_hdl == NULL)) { \ ZFS_EXIT(ZTOZSB(zp)); \ return (error); \ } \