I ran the test suite with --with-spinlock=gcc configured and saw a failure today.
Here's the stack:
Breakpoint 3, __lsm_discard_handle (session=0x805d7e630,
uri=0x806c07100 "file:test_backup.2-000009.lsm", checkpoint=0x0)
at ../src/lsm/lsm_worker.c:506
506 WT_TRET(__wt_session_release_btree(session));
(gdb) where
#0 __lsm_discard_handle (session=0x805d7e630,
uri=0x806c07100 "file:test_backup.2-000009.lsm", checkpoint=0x0)
at ../src/lsm/lsm_worker.c:506
WT-1 0x00000008036fc574 in __wt_lsm_checkpoint_worker (arg=0x801632100)
at ../src/lsm/lsm_worker.c:296
*lsm_discard_handle returns any error from *wt_spin_trylock:
locked = 0; if ((ret = __wt_spin_trylock(session, &S2C(session)->checkpoint_lock)) == 0) { locked = 1; F_SET(session->dhandle, WT_DHANDLE_DISCARD); } WT_TRET(__wt_session_release_btree(session)); if (locked) __wt_spin_unlock(session, &S2C(session)->checkpoint_lock); return (ret);
and __wt_lsm_checkpoint_worker checks that return for EBUSY:
/* * If the chunk is already checkpointed, make sure it * is also evicted. Either way, there is no point * trying to checkpoint it again. */ if (F_ISSET(chunk, WT_LSM_CHUNK_ONDISK)) { if (F_ISSET(chunk, WT_LSM_CHUNK_EVICTED)) continue; if ((ret = __lsm_discard_handle( session, chunk->uri, NULL)) == 0) F_SET(chunk, WT_LSM_CHUNK_EVICTED); else if (ret == EBUSY) ret = 0; else WT_ERR_MSG(session, ret, "discard handle"); continue; }
EBUSY is what pthread_mutex_trylock returns, but the gcc spinlock implementation of __wt_spin_trylock returns 0/1.
Maybe wiredtiger-spinlock-gcc should have it's own test test-unit downstream project?
- related to
-
WT-1 placeholder WT-1
- Closed