diff options
| author | Chunwei Chen <[email protected]> | 2016-12-21 10:47:15 -0800 |
|---|---|---|
| committer | Brian Behlendorf <[email protected]> | 2016-12-21 10:47:15 -0800 |
| commit | da8f51e16aa4e1832f8c1a9ddc3082e4469b4485 (patch) | |
| tree | afa7bb50215497f1bddfcfcfc71b95cb97ef428f /module/zfs/vdev_file.c | |
| parent | 5f1346c29997dd4e02acf4c19c875d5484f33b1e (diff) | |
Use a dedicated taskq for vdev_file
The introduction of parallel zvol prefetch causes deadlock when using
vdev_file.
spa_async->(spa_namespace_lock)->txg_wait_synced->(wait for txg_sync)
txg_sync->zio_wait->(wait for vdev_file_io_fsync on system_taskq)
zvol_prefetch_minors_impl (on system_taskq)->spa_open_common->(wait for spa_namespace_lock)
We fix this by using dedicated taskq for vdev_file. This same change
was originally made in commit bc25c93 but reverted in commit aa9af22
when dynamic taskqs were added.
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Chunwei Chen <[email protected]>
Closes #5506
Closes #5495
Diffstat (limited to 'module/zfs/vdev_file.c')
| -rw-r--r-- | module/zfs/vdev_file.c | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/module/zfs/vdev_file.c b/module/zfs/vdev_file.c index c78f2f421..54a50c318 100644 --- a/module/zfs/vdev_file.c +++ b/module/zfs/vdev_file.c @@ -37,6 +37,8 @@ * Virtual device vector for files. */ +static taskq_t *vdev_file_taskq; + static void vdev_file_hold(vdev_t *vd) { @@ -212,7 +214,7 @@ vdev_file_io_start(zio_t *zio) * the sync must be dispatched to a different context. */ if (spl_fstrans_check()) { - VERIFY3U(taskq_dispatch(system_taskq, + VERIFY3U(taskq_dispatch(vdev_file_taskq, vdev_file_io_fsync, zio, TQ_SLEEP), !=, TASKQID_INVALID); return; @@ -231,7 +233,7 @@ vdev_file_io_start(zio_t *zio) zio->io_target_timestamp = zio_handle_io_delay(zio); - VERIFY3U(taskq_dispatch(system_taskq, vdev_file_io_strategy, zio, + VERIFY3U(taskq_dispatch(vdev_file_taskq, vdev_file_io_strategy, zio, TQ_SLEEP), !=, TASKQID_INVALID); } @@ -254,6 +256,21 @@ vdev_ops_t vdev_file_ops = { B_TRUE /* leaf vdev */ }; +void +vdev_file_init(void) +{ + vdev_file_taskq = taskq_create("z_vdev_file", MAX(boot_ncpus, 16), + minclsyspri, boot_ncpus, INT_MAX, TASKQ_DYNAMIC); + + VERIFY(vdev_file_taskq); +} + +void +vdev_file_fini(void) +{ + taskq_destroy(vdev_file_taskq); +} + /* * From userland we access disks just like files. */ |