From ee720ad7bca88997dd92370c295723a0f1aca3b2 Mon Sep 17 00:00:00 2001 From: Mateusz Guzik Date: Tue, 19 Sep 2023 01:53:33 +0200 Subject: [PATCH] Retire z_nr_znodes Added in ab26409db753 ("Linux 3.1 compat, super_block->s_shrink"), with the only consumer which needed the count getting retired in 066e82522101 ("Linux compat: Minimum kernel version 3.10"). The counter gets in the way of not maintaining the list to begin with. Reviewed-by: Brian Behlendorf Reviewed-by: Alexander Motin Signed-off-by: Mateusz Guzik Closes #15274 --- include/os/freebsd/zfs/sys/zfs_vfsops_os.h | 1 - include/os/linux/zfs/sys/zfs_vfsops_os.h | 1 - module/os/freebsd/zfs/zfs_vfsops.c | 8 +++----- module/os/freebsd/zfs/zfs_znode.c | 2 -- module/os/linux/zfs/zfs_ctldir.c | 1 - module/os/linux/zfs/zfs_vfsops.c | 7 +++---- module/os/linux/zfs/zfs_znode.c | 2 -- 7 files changed, 6 insertions(+), 16 deletions(-) diff --git a/include/os/freebsd/zfs/sys/zfs_vfsops_os.h b/include/os/freebsd/zfs/sys/zfs_vfsops_os.h index f765d38db..24bb03575 100644 --- a/include/os/freebsd/zfs/sys/zfs_vfsops_os.h +++ b/include/os/freebsd/zfs/sys/zfs_vfsops_os.h @@ -93,7 +93,6 @@ struct zfsvfs { zfs_teardown_lock_t z_teardown_lock; zfs_teardown_inactive_lock_t z_teardown_inactive_lock; list_t z_all_znodes; /* all vnodes in the fs */ - uint64_t z_nr_znodes; /* number of znodes in the fs */ kmutex_t z_znodes_lock; /* lock for z_all_znodes */ struct zfsctl_root *z_ctldir; /* .zfs directory pointer */ boolean_t z_show_ctldir; /* expose .zfs in the root dir */ diff --git a/include/os/linux/zfs/sys/zfs_vfsops_os.h b/include/os/linux/zfs/sys/zfs_vfsops_os.h index e320b8de4..b4d5db21f 100644 --- a/include/os/linux/zfs/sys/zfs_vfsops_os.h +++ b/include/os/linux/zfs/sys/zfs_vfsops_os.h @@ -105,7 +105,6 @@ struct zfsvfs { rrmlock_t z_teardown_lock; krwlock_t z_teardown_inactive_lock; list_t z_all_znodes; /* all znodes in the fs */ - uint64_t z_nr_znodes; /* number of znodes in the fs */ unsigned long z_rollback_time; /* last online rollback time */ unsigned long z_snap_defer_time; /* last snapshot unmount deferral */ kmutex_t z_znodes_lock; /* lock for z_all_znodes */ diff --git a/module/os/freebsd/zfs/zfs_vfsops.c b/module/os/freebsd/zfs/zfs_vfsops.c index 33759fa26..e8b9ada13 100644 --- a/module/os/freebsd/zfs/zfs_vfsops.c +++ b/module/os/freebsd/zfs/zfs_vfsops.c @@ -1154,7 +1154,6 @@ zfsvfs_free(zfsvfs_t *zfsvfs) mutex_destroy(&zfsvfs->z_znodes_lock); mutex_destroy(&zfsvfs->z_lock); - ASSERT3U(zfsvfs->z_nr_znodes, ==, 0); list_destroy(&zfsvfs->z_all_znodes); ZFS_TEARDOWN_DESTROY(zfsvfs); ZFS_TEARDOWN_INACTIVE_DESTROY(zfsvfs); @@ -1558,12 +1557,11 @@ zfsvfs_teardown(zfsvfs_t *zfsvfs, boolean_t unmounting) * may add the parents of dir-based xattrs to the taskq * so we want to wait for these. * - * We can safely read z_nr_znodes without locking because the - * VFS has already blocked operations which add to the - * z_all_znodes list and thus increment z_nr_znodes. + * We can safely check z_all_znodes for being empty because the + * VFS has already blocked operations which add to it. */ int round = 0; - while (zfsvfs->z_nr_znodes > 0) { + while (!list_is_empty(&zfsvfs->z_all_znodes)) { taskq_wait_outstanding(dsl_pool_zrele_taskq( dmu_objset_pool(zfsvfs->z_os)), 0); if (++round > 1 && !unmounting) diff --git a/module/os/freebsd/zfs/zfs_znode.c b/module/os/freebsd/zfs/zfs_znode.c index c4f2b722e..0d4c94555 100644 --- a/module/os/freebsd/zfs/zfs_znode.c +++ b/module/os/freebsd/zfs/zfs_znode.c @@ -537,7 +537,6 @@ zfs_znode_alloc(zfsvfs_t *zfsvfs, dmu_buf_t *db, int blksz, mutex_enter(&zfsvfs->z_znodes_lock); list_insert_tail(&zfsvfs->z_all_znodes, zp); - zfsvfs->z_nr_znodes++; zp->z_zfsvfs = zfsvfs; mutex_exit(&zfsvfs->z_znodes_lock); @@ -1286,7 +1285,6 @@ zfs_znode_free(znode_t *zp) mutex_enter(&zfsvfs->z_znodes_lock); POINTER_INVALIDATE(&zp->z_zfsvfs); list_remove(&zfsvfs->z_all_znodes, zp); - zfsvfs->z_nr_znodes--; mutex_exit(&zfsvfs->z_znodes_lock); #if __FreeBSD_version >= 1300139 diff --git a/module/os/linux/zfs/zfs_ctldir.c b/module/os/linux/zfs/zfs_ctldir.c index c45a3eb5a..02cb379ea 100644 --- a/module/os/linux/zfs/zfs_ctldir.c +++ b/module/os/linux/zfs/zfs_ctldir.c @@ -537,7 +537,6 @@ zfsctl_inode_alloc(zfsvfs_t *zfsvfs, uint64_t id, mutex_enter(&zfsvfs->z_znodes_lock); list_insert_tail(&zfsvfs->z_all_znodes, zp); - zfsvfs->z_nr_znodes++; membar_producer(); mutex_exit(&zfsvfs->z_znodes_lock); diff --git a/module/os/linux/zfs/zfs_vfsops.c b/module/os/linux/zfs/zfs_vfsops.c index 464c12e11..a1db5c57c 100644 --- a/module/os/linux/zfs/zfs_vfsops.c +++ b/module/os/linux/zfs/zfs_vfsops.c @@ -1330,12 +1330,11 @@ zfsvfs_teardown(zfsvfs_t *zfsvfs, boolean_t unmounting) * may add the parents of dir-based xattrs to the taskq * so we want to wait for these. * - * We can safely read z_nr_znodes without locking because the - * VFS has already blocked operations which add to the - * z_all_znodes list and thus increment z_nr_znodes. + * We can safely check z_all_znodes for being empty because the + * VFS has already blocked operations which add to it. */ int round = 0; - while (zfsvfs->z_nr_znodes > 0) { + while (!list_is_empty(&zfsvfs->z_all_znodes)) { taskq_wait_outstanding(dsl_pool_zrele_taskq( dmu_objset_pool(zfsvfs->z_os)), 0); if (++round > 1 && !unmounting) diff --git a/module/os/linux/zfs/zfs_znode.c b/module/os/linux/zfs/zfs_znode.c index 335ae3460..52c8e51df 100644 --- a/module/os/linux/zfs/zfs_znode.c +++ b/module/os/linux/zfs/zfs_znode.c @@ -390,7 +390,6 @@ zfs_inode_destroy(struct inode *ip) mutex_enter(&zfsvfs->z_znodes_lock); if (list_link_active(&zp->z_link_node)) { list_remove(&zfsvfs->z_all_znodes, zp); - zfsvfs->z_nr_znodes--; } mutex_exit(&zfsvfs->z_znodes_lock); @@ -641,7 +640,6 @@ zfs_znode_alloc(zfsvfs_t *zfsvfs, dmu_buf_t *db, int blksz, mutex_enter(&zfsvfs->z_znodes_lock); list_insert_tail(&zfsvfs->z_all_znodes, zp); - zfsvfs->z_nr_znodes++; mutex_exit(&zfsvfs->z_znodes_lock); if (links > 0)