diff options
| author | Richard Yao <[email protected]> | 2012-04-16 06:56:20 -0400 |
|---|---|---|
| committer | Brian Behlendorf <[email protected]> | 2012-04-30 11:25:36 -0700 |
| commit | ce90208cf9e04df966429f115d8831371ea9afce (patch) | |
| tree | 9c343a6f5181463626f6824f84f23785c7f8e408 | |
| parent | 518b4876022eee58b14903da09b99c01b8caa754 (diff) | |
Disable direct reclaim on zvols
Previously, it was possible for the direct reclaim path to be invoked
when a write to a zvol was made. When a zvol is used as a swap device,
this often causes swap requests to depend on additional swap requests,
which deadlocks. We address this by disabling the direct reclaim path
on zvols.
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #342
| -rw-r--r-- | module/zfs/zvol.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/module/zfs/zvol.c b/module/zfs/zvol.c index 9b1313402..9dd9547e2 100644 --- a/module/zfs/zvol.c +++ b/module/zfs/zvol.c @@ -1390,8 +1390,14 @@ zvol_init(void) { int error; + /* + * The zvol taskqs are created with TASKQ_NORECLAIM so they may be + * used safely as a swap device. If direct reclaim is allowed then + * they quickly deadlock in one of the internal memory allocations. + */ zvol_taskq = taskq_create(ZVOL_DRIVER, zvol_threads, maxclsyspri, - zvol_threads, INT_MAX, TASKQ_PREPOPULATE); + zvol_threads, INT_MAX, + TASKQ_PREPOPULATE | TASKQ_NORECLAIM); if (zvol_taskq == NULL) { printk(KERN_INFO "ZFS: taskq_create() failed\n"); return (-ENOMEM); |