Commit 16ef80ee authored by NeilBrown's avatar NeilBrown Committed by Chuck Lever
Browse files

sunrpc: document locking rules for svc_exit_thread() 



The locking required for svc_exit_thread() is not obvious, so document
it in a kdoc comment.

Signed-off-by: default avatarNeilBrown <neilb@suse.de>
Reviewed-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 73598a0c

net/sunrpc/svc.c

+14 −0
Original line number Diff line number Diff line
@@ -945,6 +945,20 @@ void svc_rqst_release_pages(struct svc_rqst *rqstp) 
	}

}



/**

 * svc_exit_thread - finalise the termination of a sunrpc server thread

 * @rqstp: the svc_rqst which represents the thread.

 *

 * When a thread started with svc_new_thread() exits it must call

 * svc_exit_thread() as its last act.  This must be done with the

 * service mutex held.  Normally this is held by a DIFFERENT thread, the

 * one that is calling svc_set_num_threads() and which will wait for

 * SP_VICTIM_REMAINS to be cleared before dropping the mutex.  If the

 * thread exits for any reason other than svc_thread_should_stop()

 * returning %true (which indicated that svc_set_num_threads() is

 * waiting for it to exit), then it must take the service mutex itself,

 * which can only safely be done using mutex_try_lock().

 */

void

svc_exit_thread(struct svc_rqst *rqstp)

{