* anchor and wakes up waiting thread when transfer is complete.
*/
struct cl_sync_io {
- /** number of pages yet to be transferred. */
- cfs_atomic_t csi_sync_nr;
- /** completion to be signaled when transfer is complete. */
- cfs_waitq_t csi_waitq;
- /** error code. */
- int csi_sync_rc;
+ /** number of pages yet to be transferred. */
+ cfs_atomic_t csi_sync_nr;
+ /** error code. */
+ int csi_sync_rc;
+ /** barrier of destroy this structure */
+ cfs_atomic_t csi_barrier;
+ /** completion to be signaled when transfer is complete. */
+ cfs_waitq_t csi_waitq;
};
void cl_sync_io_init(struct cl_sync_io *anchor, int nrpages);
*/
void cl_sync_io_init(struct cl_sync_io *anchor, int nrpages)
{
- ENTRY;
- cfs_waitq_init(&anchor->csi_waitq);
- cfs_atomic_set(&anchor->csi_sync_nr, nrpages);
- anchor->csi_sync_rc = 0;
- EXIT;
+ ENTRY;
+ cfs_waitq_init(&anchor->csi_waitq);
+ cfs_atomic_set(&anchor->csi_sync_nr, nrpages);
+ cfs_atomic_set(&anchor->csi_barrier, nrpages > 0);
+ anchor->csi_sync_rc = 0;
+ EXIT;
}
EXPORT_SYMBOL(cl_sync_io_init);
}
LASSERT(cfs_atomic_read(&anchor->csi_sync_nr) == 0);
cl_page_list_assume(env, io, queue);
- POISON(anchor, 0x5a, sizeof *anchor);
- RETURN(rc);
+
+ /* wait until cl_sync_io_note() has done wakeup */
+ while (unlikely(cfs_atomic_read(&anchor->csi_barrier) != 0)) {
+#ifdef __KERNEL__
+ cpu_relax();
+#endif
+ }
+
+ POISON(anchor, 0x5a, sizeof *anchor);
+ RETURN(rc);
}
EXPORT_SYMBOL(cl_sync_io_wait);
* IO.
*/
LASSERT(cfs_atomic_read(&anchor->csi_sync_nr) > 0);
- if (cfs_atomic_dec_and_test(&anchor->csi_sync_nr))
- cfs_waitq_broadcast(&anchor->csi_waitq);
- EXIT;
+ if (cfs_atomic_dec_and_test(&anchor->csi_sync_nr)) {
+ cfs_waitq_broadcast(&anchor->csi_waitq);
+ /* it's safe to nuke or reuse anchor now */
+ cfs_atomic_set(&anchor->csi_barrier, 0);
+ }
+ EXIT;
}
EXPORT_SYMBOL(cl_sync_io_note);