[sheepdog] [PATCH 1/2] work: allow worker threads to call suspend_worker_threads()

[MORITA Kazutaka]

From: MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>

With this patch, if we call suspend_worker_threads() in a worker
thread, the function suspends the other worker threads and the main
thread.

This prepares for the next patch.

Signed-off-by: MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>
---
 lib/work.c |    7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/work.c b/lib/work.c
index 6933e1a..f19e315 100644
--- a/lib/work.c
+++ b/lib/work.c
@@ -165,6 +165,8 @@ void suspend_worker_threads(void)
 	}
 
 	FOR_EACH_BIT(tid, tid_map, tid_max) {
+		if (tid == gettid())
+			continue;
 		if (unlikely(tkill(tid, SIGUSR2) < 0))
 			panic("%m");
 	}
@@ -175,6 +177,8 @@ void suspend_worker_threads(void)
 	 * yet (then, the thread doesn't recieve SIGUSR2).
 	 */
 	FOR_EACH_BIT(tid, tid_map, tid_max) {
+		if (tid == gettid())
+			continue;
 		eventfd_xread(ack_efd);
 	}
 }
@@ -185,6 +189,8 @@ void resume_worker_threads(void)
 	int nr_threads = 0, tid;
 
 	FOR_EACH_BIT(tid, tid_map, tid_max) {
+		if (tid == gettid())
+			continue;
 		nr_threads++;
 	}
 
@@ -323,6 +329,7 @@ int init_work_queue(size_t (*get_nr_nodes)(void))
 
 	tid_max = TID_MAX_DEFAULT;
 	tid_map = alloc_bitmap(NULL, 0, tid_max);
+	set_bit(getpid(), tid_map);
 
 	resume_efd = eventfd(0, EFD_SEMAPHORE);
 	ack_efd = eventfd(0, EFD_SEMAPHORE);
-- 
1.7.9.5