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authorMauro Carvalho Chehab <mchehab@redhat.com>2013-01-24 18:49:18 -0200
committerMauro Carvalho Chehab <mchehab@redhat.com>2013-01-24 18:49:18 -0200
commita32f7d1ad3744914273c6907204c2ab3b5d496a0 (patch)
tree1c5ae321ee85665707177547c07810ff7e09e1ab /net/sunrpc
parent6b9e50c463efc5c361496ae6a895cc966ff8025b (diff)
parent68d6f84ba0c47e658beff3a4bf0c43acee4b4690 (diff)
downloadblackbird-op-linux-a32f7d1ad3744914273c6907204c2ab3b5d496a0.tar.gz
blackbird-op-linux-a32f7d1ad3744914273c6907204c2ab3b5d496a0.zip
Merge branch 'v4l_for_linus' into staging/for_v3.9
* v4l_for_linus: (464 commits) [media] uvcvideo: Set error_idx properly for S_EXT_CTRLS failures [media] uvcvideo: Cleanup leftovers of partial revert [media] uvcvideo: Return -EACCES when trying to set a read-only control Linux 3.8-rc3 mm: reinstante dropped pmd_trans_splitting() check cred: Remove tgcred pointer from struct cred drm/ttm: fix fence locking in ttm_buffer_object_transfer ARM: clps711x: Fix bad merge of clockevents setup ARM: highbank: save and restore L2 cache and GIC on suspend ARM: highbank: add a power request clear ARM: highbank: fix secondary boot and hotplug ARM: highbank: fix typos with hignbank in power request functions ARM: dts: fix highbank cpu mpidr values ARM: dts: add device_type prop to cpu nodes on Calxeda platforms drm/prime: drop reference on imported dma-buf come from gem xen/netfront: improve truesize tracking ARM: mx5: Fix MX53 flexcan2 clock ARM: OMAP2+: am33xx-hwmod: Fix wrongly terminated am33xx_usbss_mpu_irqs array sctp: fix Kconfig bug in default cookie hmac selection EDAC: Cleanup device deregistering path ... Conflicts: drivers/media/pci/dm1105/dm1105.c drivers/media/platform/soc_camera/mx2_camera.c
Diffstat (limited to 'net/sunrpc')
-rw-r--r--net/sunrpc/clnt.c5
-rw-r--r--net/sunrpc/sched.c27
2 files changed, 23 insertions, 9 deletions
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 822f020fa7f4..1915ffe598e3 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -610,11 +610,6 @@ EXPORT_SYMBOL_GPL(rpc_killall_tasks);
*/
void rpc_shutdown_client(struct rpc_clnt *clnt)
{
- /*
- * To avoid deadlock, never call rpc_shutdown_client from a
- * workqueue context!
- */
- WARN_ON_ONCE(current->flags & PF_WQ_WORKER);
might_sleep();
dprintk_rcu("RPC: shutting down %s client for %s\n",
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index d17a704aaf5f..b4133bd13915 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -934,16 +934,35 @@ struct rpc_task *rpc_new_task(const struct rpc_task_setup *setup_data)
return task;
}
+/*
+ * rpc_free_task - release rpc task and perform cleanups
+ *
+ * Note that we free up the rpc_task _after_ rpc_release_calldata()
+ * in order to work around a workqueue dependency issue.
+ *
+ * Tejun Heo states:
+ * "Workqueue currently considers two work items to be the same if they're
+ * on the same address and won't execute them concurrently - ie. it
+ * makes a work item which is queued again while being executed wait
+ * for the previous execution to complete.
+ *
+ * If a work function frees the work item, and then waits for an event
+ * which should be performed by another work item and *that* work item
+ * recycles the freed work item, it can create a false dependency loop.
+ * There really is no reliable way to detect this short of verifying
+ * every memory free."
+ *
+ */
static void rpc_free_task(struct rpc_task *task)
{
- const struct rpc_call_ops *tk_ops = task->tk_ops;
- void *calldata = task->tk_calldata;
+ unsigned short tk_flags = task->tk_flags;
+
+ rpc_release_calldata(task->tk_ops, task->tk_calldata);
- if (task->tk_flags & RPC_TASK_DYNAMIC) {
+ if (tk_flags & RPC_TASK_DYNAMIC) {
dprintk("RPC: %5u freeing task\n", task->tk_pid);
mempool_free(task, rpc_task_mempool);
}
- rpc_release_calldata(tk_ops, calldata);
}
static void rpc_async_release(struct work_struct *work)
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