diff options
| author | Brian Foster <bfoster@redhat.com> | 2013-10-18 07:36:38 -0400 |
|---|---|---|
| committer | Anand Avati <avati@redhat.com> | 2013-11-10 23:45:46 -0800 |
| commit | b06ecde2997b72a41b2f2d25d55e61d30ea46bc2 (patch) | |
| tree | ff630d050b46310141d0ca11ee56b04736d06cea /xlators/features/qemu-block/src/qemu-block.h | |
| parent | 0826f9073a93c6d499f3d2077695455854d0fa7f (diff) | |
features/qemu-block: simplify coroutine model to use single synctask, ucontext
The current coroutine model, mapping synctasks 1-1 with qemu internal
Coroutines, has some unresolved raciness issues. This problem usually
manifests as lifecycle mismatches between top-level (gluster created)
synctasks and the subsequently created internal coroutines from that
context. Qemu's internal queueing (and locking) can cause situations
where the top-level synctask is destroyed before the internal scheduler
has released references to memory, leading to use after free crashes
and asserts.
Simplify the coroutine model to use a single synctask as a coroutine
processor and rely on the existing native ucontext coroutine
implementation. The syncenv thread is donated to qemu and ensures a
single top-level coroutine is processed at a time. Qemu now has
complete control over coroutine scheduling.
BUG: 986775
Change-Id: I38223479a608d80353128e390f243933fc946fd6
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-on: http://review.gluster.org/6110
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>
Diffstat (limited to 'xlators/features/qemu-block/src/qemu-block.h')
| -rw-r--r-- | xlators/features/qemu-block/src/qemu-block.h | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/xlators/features/qemu-block/src/qemu-block.h b/xlators/features/qemu-block/src/qemu-block.h index 55e7c23ac58..c95f2799ac6 100644 --- a/xlators/features/qemu-block/src/qemu-block.h +++ b/xlators/features/qemu-block/src/qemu-block.h @@ -15,7 +15,6 @@ #include "call-stub.h" #include "block/block_int.h" #include "monitor/monitor.h" -#include "coroutine-synctask.h" /* QB_XATTR_KEY_FMT is the on-disk xattr stored in the inode which indicates that the file must be "interpreted" by the block format @@ -59,7 +58,6 @@ typedef struct qb_conf { typedef struct qb_local { - CoroutineSynctask cs; call_frame_t *frame; /* backpointer */ call_stub_t *stub; inode_t *inode; @@ -67,6 +65,7 @@ typedef struct qb_local { char fmt[QB_XATTR_VAL_MAX+1]; char name[256]; synctask_fn_t synctask_fn; + struct list_head list; } qb_local_t; void qb_local_free (xlator_t *this, qb_local_t *local); |