svn commit: r310469 - stable/11/sys/kern

[Konstantin Belousov]

Author: kib
Date: Fri Dec 23 09:27:25 2016
New Revision: 310469
URL: https://svnweb.freebsd.org/changeset/base/310469

Log:
  MFC r310159:
  Switch from stdatomic.h to atomic.h for kernel.

Modified:
  stable/11/sys/kern/kern_event.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/kern/kern_event.c
==============================================================================
--- stable/11/sys/kern/kern_event.c	Fri Dec 23 09:10:57 2016	(r310468)
+++ stable/11/sys/kern/kern_event.c	Fri Dec 23 09:27:25 2016	(r310469)
@@ -48,7 +48,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/fcntl.h>
 #include <sys/kthread.h>
 #include <sys/selinfo.h>
-#include <sys/stdatomic.h>
 #include <sys/queue.h>
 #include <sys/event.h>
 #include <sys/eventvar.h>
@@ -69,6 +68,7 @@ __FBSDID("$FreeBSD$");
 #ifdef KTRACE
 #include <sys/ktrace.h>
 #endif
+#include <machine/atomic.h>
 
 #include <vm/uma.h>
 
@@ -188,7 +188,7 @@ static struct filterops user_filtops = {
 };
 
 static uma_zone_t	knote_zone;
-static atomic_uint	kq_ncallouts = ATOMIC_VAR_INIT(0);
+static unsigned int	kq_ncallouts = 0;
 static unsigned int 	kq_calloutmax = 4 * 1024;
 SYSCTL_UINT(_kern, OID_AUTO, kq_calloutmax, CTLFLAG_RW,
     &kq_calloutmax, 0, "Maximum number of callouts allocated for kqueue");
@@ -672,13 +672,11 @@ filt_timerattach(struct knote *kn)
 	if (to < 0)
 		return (EINVAL);
 
-	ncallouts = atomic_load_explicit(&kq_ncallouts, memory_order_relaxed);
 	do {
+		ncallouts = kq_ncallouts;
 		if (ncallouts >= kq_calloutmax)
 			return (ENOMEM);
-	} while (!atomic_compare_exchange_weak_explicit(&kq_ncallouts,
-	    &ncallouts, ncallouts + 1, memory_order_relaxed,
-	    memory_order_relaxed));
+	} while (!atomic_cmpset_int(&kq_ncallouts, ncallouts, ncallouts + 1));
 
 	kn->kn_flags |= EV_CLEAR;		/* automatically set */
 	kn->kn_status &= ~KN_DETACHED;		/* knlist_add clears it */
@@ -703,7 +701,7 @@ filt_timerdetach(struct knote *kn)
 	callout_drain(calloutp);
 	free(calloutp, M_KQUEUE);
 	free(kn->kn_ptr.p_nexttime, M_KQUEUE);
-	old = atomic_fetch_sub_explicit(&kq_ncallouts, 1, memory_order_relaxed);
+	old = atomic_fetchadd_int(&kq_ncallouts, -1);
 	KASSERT(old > 0, ("Number of callouts cannot become negative"));
 	kn->kn_status |= KN_DETACHED;	/* knlist_remove sets it */
 }