diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2013-01-19 15:27:30 +0000 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2013-01-19 15:27:30 +0000 |
| commit | 210b1847b32951f52d19df229972399e5b987de2 (patch) | |
| tree | be6eeb3ba76b4f4331c98d5ba47aa233bea8f22d /net/sunrpc/sched.c | |
| parent | 93d5bf073a1e01035be66dc41860b9ae9aa9ccfa (diff) | |
| parent | d01723479e6a6c70c83295f7847477a016d5e14a (diff) | |
Merge branch 'for-rmk/virt/hyp-boot/fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into fixes
Diffstat (limited to 'net/sunrpc/sched.c')
| -rw-r--r-- | net/sunrpc/sched.c | 27 |
1 files changed, 23 insertions, 4 deletions
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) |