When doing signotify, check if we're notifying a process on another

cpu and if we do, send it an IPI that will force to get into the kernel
and process the AST.

This makes signals to processes on other CPUs to be actually delivered
as soon as possible instead of some time in the future when some
interupt happens.

heavy testing by krw@, miod@ ok (in principle, since he doesn't do amd64)

2 files changed, 17 insertions, 7 deletions

diff --git a/sys/arch/amd64/amd64/machdep.c b/sys/arch/amd64/amd64/machdep.c
index 867e86a4f9a..7c464b5a3a3 100644
--- a/sys/arch/amd64/amd64/machdep.c
+++ b/sys/arch/amd64/amd64/machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: machdep.c,v 1.53 2007/01/15 23:19:05 jsg Exp $	*/
+/*	$OpenBSD: machdep.c,v 1.54 2007/02/01 20:42:17 art Exp $	*/
 /*	$NetBSD: machdep.c,v 1.3 2003/05/07 22:58:18 fvdl Exp $	*/
 
 /*-
@@ -844,6 +844,20 @@ sys_sigreturn(struct proc *p, void *v, register_t *retval)
 	return (EJUSTRETURN);
 }
 
+/*
+ * Notify the current process (p) that it has a signal pending,
+ * process as soon as possible.
+ */
+void
+signotify(struct proc *p)
+{
+	aston(p);
+#ifdef MULTIPROCESSOR
+	if (p->p_cpu != curcpu() && p->p_cpu != NULL)
+		x86_send_ipi(p->p_cpu, X86_IPI_NOP);
+#endif
+}
+
 int	waittime = -1;
 struct pcb dumppcb;
 
diff --git a/sys/arch/amd64/include/cpu.h b/sys/arch/amd64/include/cpu.h
index cf4f6ced4a6..4c95f710946 100644
--- a/sys/arch/amd64/include/cpu.h
+++ b/sys/arch/amd64/include/cpu.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.h,v 1.23 2006/12/24 20:30:35 miod Exp $	*/
+/*	$OpenBSD: cpu.h,v 1.24 2007/02/01 20:42:17 art Exp $	*/
 /*	$NetBSD: cpu.h,v 1.1 2003/04/26 18:39:39 fvdl Exp $	*/
 
 /*-
@@ -229,11 +229,7 @@ extern u_int32_t cpus_attached;
  */
 #define	need_proftick(p)	((p)->p_flag |= P_OWEUPC, aston(p))
 
-/*
- * Notify the current process (p) that it has a signal pending,
- * process as soon as possible.
- */
-#define	signotify(p)		aston(p)
+void signotify(struct proc *);
 
 /*
  * We need a machine-independent name for this.