From: Heesub Shin <heesub.shin@samsung.com>
Date: Thu, 6 Apr 2017 01:56:27 +0000 (+0900)
Subject: fs: disable priority inheritance on all signaling semaphores
X-Git-Tag: 1.1_Public_Release~614^2~108
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c883f9bc520361ac891d7246bad97f117be6d7e5;p=rtos%2Ftinyara.git

fs: disable priority inheritance on all signaling semaphores

Disable priority inheritance on all semaphores used for signaling.

Change-Id: I2d032767bff07012d7724a2228705dc125d42fd8
Signed-off-by: Gregory Nutt <gnutt@nuttx.org>
[Shin: backported dbbe46a2 from NuttX]
Signed-off-by: Heesub Shin <heesub.shin@samsung.com>
---

diff --git a/os/fs/vfs/fs_poll.c b/os/fs/vfs/fs_poll.c
index d4740a7..dd4a903 100644
--- a/os/fs/vfs/fs_poll.c
+++ b/os/fs/vfs/fs_poll.c
@@ -66,6 +66,7 @@
 #include <tinyara/sched.h>
 #include <tinyara/clock.h>
 #include <tinyara/cancelpt.h>
+#include <tinyara/semaphore.h>
 #include <tinyara/fs/fs.h>
 
 #ifdef CONFIG_NET_LWIP
@@ -321,7 +322,13 @@ int poll(FAR struct pollfd *fds, nfds_t nfds, int timeout)
 	/* poll() is a cancellation point */
 	(void)enter_cancellation_point();
 
+	/*
+	 * This semaphore is used for signaling and, hence, should not have
+	 * priority inheritance enabled.
+	 */
 	sem_init(&sem, 0, 0);
+	sem_setprotocol(&sem, SEM_PRIO_NONE);
+
 	ret = poll_setup(fds, nfds, &sem);
 	if (ret >= 0) {
 		if (timeout == 0) {