CVS commit: src/sys/kern

[Taylor R Campbell]

Module Name:    src
Committed By:   riastradh
Date:           Sun Apr  9 08:50:20 UTC 2023

Modified Files:
        src/sys/kern: subr_kmem.c

Log Message:
kmem(9): Tweak branch predictions in fast paths.


To generate a diff of this commit:
cvs rdiff -u -r1.87 -r1.88 src/sys/kern/subr_kmem.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/kern/subr_kmem.c
diff -u src/sys/kern/subr_kmem.c:1.87 src/sys/kern/subr_kmem.c:1.88
--- src/sys/kern/subr_kmem.c:1.87	Mon May 30 23:36:26 2022
+++ src/sys/kern/subr_kmem.c	Sun Apr  9 08:50:20 2023
@@ -1,4 +1,4 @@
-/*	$NetBSD: subr_kmem.c,v 1.87 2022/05/30 23:36:26 mrg Exp $	*/
+/*	$NetBSD: subr_kmem.c,v 1.88 2023/04/09 08:50:20 riastradh Exp $	*/
 
 /*
  * Copyright (c) 2009-2020 The NetBSD Foundation, Inc.
@@ -78,7 +78,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_kmem.c,v 1.87 2022/05/30 23:36:26 mrg Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_kmem.c,v 1.88 2023/04/09 08:50:20 riastradh Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_kmem.h"
@@ -346,7 +346,7 @@ kmem_intr_zalloc(size_t size, km_flag_t 
 	void *p;
 
 	p = kmem_intr_alloc(size, kmflags);
-	if (p != NULL) {
+	if (__predict_true(p != NULL)) {
 		memset(p, 0, size);
 	}
 	return p;
@@ -406,8 +406,9 @@ kmem_alloc(size_t size, km_flag_t kmflag
 {
 	void *v;
 
-	KASSERTMSG((!cpu_intr_p() && !cpu_softintr_p()),
-	    "kmem(9) should not be used from the interrupt context");
+	KASSERT(!cpu_intr_p());
+	KASSERT(!cpu_softintr_p());
+
 	v = kmem_intr_alloc(size, kmflags);
 	if (__predict_true(v != NULL)) {
 		kmsan_mark(v, size, KMSAN_STATE_UNINIT);
@@ -426,8 +427,9 @@ kmem_zalloc(size_t size, km_flag_t kmfla
 {
 	void *v;
 
-	KASSERTMSG((!cpu_intr_p() && !cpu_softintr_p()),
-	    "kmem(9) should not be used from the interrupt context");
+	KASSERT(!cpu_intr_p());
+	KASSERT(!cpu_softintr_p());
+
 	v = kmem_intr_zalloc(size, kmflags);
 	KASSERT(v || (kmflags & KM_NOSLEEP) != 0);
 	return v;
@@ -440,8 +442,10 @@ kmem_zalloc(size_t size, km_flag_t kmfla
 void
 kmem_free(void *p, size_t size)
 {
+
 	KASSERT(!cpu_intr_p());
 	KASSERT(!cpu_softintr_p());
+
 	kmem_intr_free(p, size);
 	kmsan_mark(p, size, KMSAN_STATE_INITED);
 }