Module Name: src
Committed By: riastradh
Date: Sat Jun 13 19:01:11 UTC 2020
Modified Files:
src/sys/arch/x86/x86: fpu.c
Log Message:
Add comments over fpu_kern_enter/leave.
To generate a diff of this commit:
cvs rdiff -u -r1.63 -r1.64 src/sys/arch/x86/x86/fpu.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/x86/x86/fpu.c
diff -u src/sys/arch/x86/x86/fpu.c:1.63 src/sys/arch/x86/x86/fpu.c:1.64
--- src/sys/arch/x86/x86/fpu.c:1.63 Sat Jun 13 19:00:18 2020
+++ src/sys/arch/x86/x86/fpu.c Sat Jun 13 19:01:11 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: fpu.c,v 1.63 2020/06/13 19:00:18 riastradh Exp $ */
+/* $NetBSD: fpu.c,v 1.64 2020/06/13 19:01:11 riastradh Exp $ */
/*
* Copyright (c) 2008, 2019 The NetBSD Foundation, Inc. All
@@ -96,7 +96,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: fpu.c,v 1.63 2020/06/13 19:00:18 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: fpu.c,v 1.64 2020/06/13 19:01:11 riastradh Exp $");
#include "opt_multiprocessor.h"
@@ -343,6 +343,15 @@ fpu_lwp_abandon(struct lwp *l)
/* -------------------------------------------------------------------------- */
+/*
+ * fpu_kern_enter()
+ *
+ * Begin using the FPU. Raises to splhigh, disabling all
+ * interrupts and rendering the thread non-preemptible; caller
+ * should not use this for long periods of time, and must call
+ * fpu_kern_leave() afterward. Non-recursive -- you cannot call
+ * fpu_kern_enter() again without calling fpu_kern_leave() first.
+ */
void
fpu_kern_enter(void)
{
@@ -375,6 +384,11 @@ fpu_kern_enter(void)
clts();
}
+/*
+ * fpu_kern_leave()
+ *
+ * End using the FPU after fpu_kern_enter().
+ */
void
fpu_kern_leave(void)
{
