Module Name: src
Committed By: ad
Date: Sun Dec 1 14:52:14 UTC 2019
Modified Files:
src/sys/arch/arm/arm: arm_machdep.c
src/sys/arch/mips/mips: cpu_subr.c
src/sys/arch/sparc/sparc: intr.c
src/sys/arch/sparc64/sparc64: machdep.c
src/sys/arch/usermode/dev: cpu.c
src/sys/arch/x86/x86: x86_machdep.c
Log Message:
Make cpu_intr_p() safe to use anywhere, i.e. outside assertions:
Don't call kpreempt_disable() / kpreempt_enable() to make sure we're not
preempted while using the value of curcpu(). Instead, observe the value of
l_ncsw before and after the check to see if we have been preempted. If
we have been preempted, then we need to retry the read.
To generate a diff of this commit:
cvs rdiff -u -r1.56 -r1.57 src/sys/arch/arm/arm/arm_machdep.c
cvs rdiff -u -r1.37 -r1.38 src/sys/arch/mips/mips/cpu_subr.c
cvs rdiff -u -r1.121 -r1.122 src/sys/arch/sparc/sparc/intr.c
cvs rdiff -u -r1.293 -r1.294 src/sys/arch/sparc64/sparc64/machdep.c
cvs rdiff -u -r1.81 -r1.82 src/sys/arch/usermode/dev/cpu.c
cvs rdiff -u -r1.129 -r1.130 src/sys/arch/x86/x86/x86_machdep.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/arm/arm/arm_machdep.c
diff -u src/sys/arch/arm/arm/arm_machdep.c:1.56 src/sys/arch/arm/arm/arm_machdep.c:1.57
--- src/sys/arch/arm/arm/arm_machdep.c:1.56 Sat Nov 23 19:40:34 2019
+++ src/sys/arch/arm/arm/arm_machdep.c Sun Dec 1 14:52:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: arm_machdep.c,v 1.56 2019/11/23 19:40:34 ad Exp $ */
+/* $NetBSD: arm_machdep.c,v 1.57 2019/12/01 14:52:13 ad Exp $ */
/*
* Copyright (c) 2001 Wasabi Systems, Inc.
@@ -80,7 +80,7 @@
#include <sys/param.h>
-__KERNEL_RCSID(0, "$NetBSD: arm_machdep.c,v 1.56 2019/11/23 19:40:34 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: arm_machdep.c,v 1.57 2019/12/01 14:52:13 ad Exp $");
#include <sys/exec.h>
#include <sys/proc.h>
@@ -260,12 +260,27 @@ cpu_need_resched(struct cpu_info *ci, st
bool
cpu_intr_p(void)
{
- struct cpu_info * const ci = curcpu();
#ifdef __HAVE_PIC_FAST_SOFTINTS
- if (ci->ci_cpl < IPL_VM)
+ int cpl;
+#endif
+ uint64_t ncsw;
+ int idepth;
+ lwp_t *l;
+
+ l = curlwp;
+ do {
+ ncsw = l->l_ncsw;
+ idepth = l->l_cpu->ci_intr_depth;
+#ifdef __HAVE_PIC_FAST_SOFTINTS
+ cpl = ci->ci_cpl;
+#endif
+ } while (__predict_false(ncsw != l->l_ncsw));
+
+#ifdef __HAVE_PIC_FAST_SOFTINTS
+ if (cpl < IPL_VM)
return false;
#endif
- return ci->ci_intr_depth != 0;
+ return idepth != 0;
}
#ifdef MODULAR
Index: src/sys/arch/mips/mips/cpu_subr.c
diff -u src/sys/arch/mips/mips/cpu_subr.c:1.37 src/sys/arch/mips/mips/cpu_subr.c:1.38
--- src/sys/arch/mips/mips/cpu_subr.c:1.37 Sun Nov 24 15:37:39 2019
+++ src/sys/arch/mips/mips/cpu_subr.c Sun Dec 1 14:52:13 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: cpu_subr.c,v 1.37 2019/11/24 15:37:39 ad Exp $ */
+/* $NetBSD: cpu_subr.c,v 1.38 2019/12/01 14:52:13 ad Exp $ */
/*-
* Copyright (c) 2010, 2019 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cpu_subr.c,v 1.37 2019/11/24 15:37:39 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cpu_subr.c,v 1.38 2019/12/01 14:52:13 ad Exp $");
#include "opt_cputype.h"
#include "opt_ddb.h"
@@ -604,11 +604,17 @@ cpu_idle(void)
bool
cpu_intr_p(void)
{
- bool rv;
- kpreempt_disable();
- rv = (curcpu()->ci_idepth != 0);
- kpreempt_enable();
- return rv;
+ uint64_t ncsw;
+ int idepth;
+ lwp_t *l;
+
+ l = curlwp;
+ do {
+ ncsw = l->l_ncsw;
+ idepth = l->l_cpu->ci_idepth;
+ } while (__predict_false(ncsw != l->l_ncsw));
+
+ return idepth != 0;
}
#ifdef MULTIPROCESSOR
Index: src/sys/arch/sparc/sparc/intr.c
diff -u src/sys/arch/sparc/sparc/intr.c:1.121 src/sys/arch/sparc/sparc/intr.c:1.122
--- src/sys/arch/sparc/sparc/intr.c:1.121 Fri Mar 1 02:33:55 2019
+++ src/sys/arch/sparc/sparc/intr.c Sun Dec 1 14:52:14 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: intr.c,v 1.121 2019/03/01 02:33:55 macallan Exp $ */
+/* $NetBSD: intr.c,v 1.122 2019/12/01 14:52:14 ad Exp $ */
/*
* Copyright (c) 1992, 1993
@@ -41,7 +41,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: intr.c,v 1.121 2019/03/01 02:33:55 macallan Exp $");
+__KERNEL_RCSID(0, "$NetBSD: intr.c,v 1.122 2019/12/01 14:52:14 ad Exp $");
#include "opt_multiprocessor.h"
#include "opt_sparc_arch.h"
@@ -889,11 +889,15 @@ intr_biglock_wrapper(void *vp)
bool
cpu_intr_p(void)
{
+ uint64_t ncsw;
int idepth;
+ lwp_t *l;
- kpreempt_disable();
- idepth = curcpu()->ci_idepth;
- kpreempt_enable();
+ l = curlwp;
+ do {
+ ncsw = l->l_ncsw;
+ idepth = l->l_cpu->ci_idepth;
+ } while (__predict_false(ncsw != l->l_ncsw));
return idepth != 0;
}
Index: src/sys/arch/sparc64/sparc64/machdep.c
diff -u src/sys/arch/sparc64/sparc64/machdep.c:1.293 src/sys/arch/sparc64/sparc64/machdep.c:1.294
--- src/sys/arch/sparc64/sparc64/machdep.c:1.293 Sat Nov 23 19:40:37 2019
+++ src/sys/arch/sparc64/sparc64/machdep.c Sun Dec 1 14:52:14 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: machdep.c,v 1.293 2019/11/23 19:40:37 ad Exp $ */
+/* $NetBSD: machdep.c,v 1.294 2019/12/01 14:52:14 ad Exp $ */
/*-
* Copyright (c) 1996, 1997, 1998, 2019 The NetBSD Foundation, Inc.
@@ -71,7 +71,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.293 2019/11/23 19:40:37 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.294 2019/12/01 14:52:14 ad Exp $");
#include "opt_ddb.h"
#include "opt_multiprocessor.h"
@@ -2654,8 +2654,17 @@ cpu_signotify(struct lwp *l)
bool
cpu_intr_p(void)
{
+ uint64_t ncsw;
+ int idepth;
+ lwp_t *l;
- return curcpu()->ci_idepth >= 0;
+ l = curlwp;
+ do {
+ ncsw = l->l_ncsw;
+ idepth = l->l_cpu->ci_idepth;
+ } while (__predict_false(ncsw != l->l_ncsw));
+
+ return idepth >= 0;
}
#ifdef MODULAR
Index: src/sys/arch/usermode/dev/cpu.c
diff -u src/sys/arch/usermode/dev/cpu.c:1.81 src/sys/arch/usermode/dev/cpu.c:1.82
--- src/sys/arch/usermode/dev/cpu.c:1.81 Sat Nov 23 19:40:37 2019
+++ src/sys/arch/usermode/dev/cpu.c Sun Dec 1 14:52:14 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: cpu.c,v 1.81 2019/11/23 19:40:37 ad Exp $ */
+/* $NetBSD: cpu.c,v 1.82 2019/12/01 14:52:14 ad Exp $ */
/*-
* Copyright (c) 2007 Jared D. McNeill <jmcne...@invisible.ca>
@@ -30,7 +30,7 @@
#include "opt_hz.h"
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.81 2019/11/23 19:40:37 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.82 2019/12/01 14:52:14 ad Exp $");
#include <sys/param.h>
#include <sys/conf.h>
@@ -528,11 +528,15 @@ cpu_rootconf(void)
bool
cpu_intr_p(void)
{
+ uint64_t ncsw;
int idepth;
+ lwp_t *l;
- kpreempt_disable();
- idepth = curcpu()->ci_idepth;
- kpreempt_enable();
+ l = curlwp;
+ do {
+ ncsw = l->l_ncsw;
+ idepth = l->l_cpu->ci_idepth;
+ } while (__predict_false(ncsw != l->l_ncsw));
- return (idepth >= 0);
+ return idepth >= 0;
}
Index: src/sys/arch/x86/x86/x86_machdep.c
diff -u src/sys/arch/x86/x86/x86_machdep.c:1.129 src/sys/arch/x86/x86/x86_machdep.c:1.130
--- src/sys/arch/x86/x86/x86_machdep.c:1.129 Sat Nov 23 19:40:37 2019
+++ src/sys/arch/x86/x86/x86_machdep.c Sun Dec 1 14:52:14 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: x86_machdep.c,v 1.129 2019/11/23 19:40:37 ad Exp $ */
+/* $NetBSD: x86_machdep.c,v 1.130 2019/12/01 14:52:14 ad Exp $ */
/*-
* Copyright (c) 2002, 2006, 2007 YAMAMOTO Takashi,
@@ -31,7 +31,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: x86_machdep.c,v 1.129 2019/11/23 19:40:37 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: x86_machdep.c,v 1.130 2019/12/01 14:52:14 ad Exp $");
#include "opt_modular.h"
#include "opt_physmem.h"
@@ -349,12 +349,17 @@ cpu_need_proftick(struct lwp *l)
bool
cpu_intr_p(void)
{
+ uint64_t ncsw;
int idepth;
+ lwp_t *l;
+
+ l = curlwp;
+ do {
+ ncsw = l->l_ncsw;
+ idepth = l->l_cpu->ci_idepth;
+ } while (__predict_false(ncsw != l->l_ncsw));
- kpreempt_disable();
- idepth = curcpu()->ci_idepth;
- kpreempt_enable();
- return (idepth >= 0);
+ return idepth >= 0;
}
#ifdef __HAVE_PREEMPTION
