CVS commit: src/sys/kern

[Taylor R Campbell]

Module Name:    src
Committed By:   riastradh
Date:           Fri Jul  7 17:04:50 UTC 2023

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

Log Message:
xcall(9): If !mp_online, raise spl or set LP_BOUND to call func.

High-priority xcalls may reasonably assume that the spl is raised to
splsoftserial, so make sure to do that in xc_broadcast.

Low-priority xcalls may reasonably enter paths that assume the lwp is
bound to a CPU, so let's make it assertable even if it doesn't have
any other consequences when !mp_online.

XXX pullup-8
XXX pullup-9
XXX pullup-10


To generate a diff of this commit:
cvs rdiff -u -r1.35 -r1.36 src/sys/kern/subr_xcall.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_xcall.c
diff -u src/sys/kern/subr_xcall.c:1.35 src/sys/kern/subr_xcall.c:1.36
--- src/sys/kern/subr_xcall.c:1.35	Sun Apr  9 09:18:09 2023
+++ src/sys/kern/subr_xcall.c	Fri Jul  7 17:04:49 2023
@@ -1,4 +1,4 @@
-/*	$NetBSD: subr_xcall.c,v 1.35 2023/04/09 09:18:09 riastradh Exp $	*/
+/*	$NetBSD: subr_xcall.c,v 1.36 2023/07/07 17:04:49 riastradh Exp $	*/
 
 /*-
  * Copyright (c) 2007-2010, 2019 The NetBSD Foundation, Inc.
@@ -74,7 +74,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_xcall.c,v 1.35 2023/04/09 09:18:09 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_xcall.c,v 1.36 2023/07/07 17:04:49 riastradh Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -262,7 +262,17 @@ xc_broadcast(unsigned int flags, xcfunc_
 	ASSERT_SLEEPABLE();
 
 	if (__predict_false(!mp_online)) {
+		int s, bound;
+
+		if (flags & XC_HIGHPRI)
+			s = splsoftserial();
+		else
+			bound = curlwp_bind();
 		(*func)(arg1, arg2);
+		if (flags & XC_HIGHPRI)
+			splx(s);
+		else
+			curlwp_bindx(bound);
 		return 0;
 	}
 
@@ -302,9 +312,8 @@ xc_barrier(unsigned int flags)
  */
 uint64_t
 xc_unicast(unsigned int flags, xcfunc_t func, void *arg1, void *arg2,
-	   struct cpu_info *ci)
+    struct cpu_info *ci)
 {
-	int s;
 
 	KASSERT(ci != NULL);
 	KASSERT(!cpu_intr_p());
@@ -312,10 +321,20 @@ xc_unicast(unsigned int flags, xcfunc_t 
 	ASSERT_SLEEPABLE();
 
 	if (__predict_false(!mp_online)) {
+		int s, bound;
+
 		KASSERT(ci == curcpu());
-		s = splsoftserial();
+
+		if (flags & XC_HIGHPRI)
+			s = splsoftserial();
+		else
+			bound = curlwp_bind();
 		(*func)(arg1, arg2);
-		splx(s);
+		if (flags & XC_HIGHPRI)
+			splx(s);
+		else
+			curlwp_bindx(bound);
+
 		return 0;
 	}