From 1993502880e623b7ce08faafe37c874fc7bc885c Mon Sep 17 00:00:00 2001
From: Jeremy Fitzhardinge <jeremy@xensource.com>
Date: Tue, 16 Oct 2007 11:51:30 -0700
Subject: [PATCH] --- yaml --- r: 70928 b: refs/heads/master c:
 91e0c5f3dad47838cb2ecc1865ce789a0b7182b1 h: refs/heads/master v: v3

---
 [refs]                          |  2 +-
 trunk/arch/x86/xen/multicalls.c | 29 ++++++++++++++++++++++++++---
 trunk/arch/x86/xen/multicalls.h |  3 +++
 3 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/[refs] b/[refs]
index 6c786a7b107f..16b9eb8e4f28 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: f0d733942750c1ee6358c3a4a1a5d7ba73b7122f
+refs/heads/master: 91e0c5f3dad47838cb2ecc1865ce789a0b7182b1
diff --git a/trunk/arch/x86/xen/multicalls.c b/trunk/arch/x86/xen/multicalls.c
index c837e8e463db..ce9c4b41f02d 100644
--- a/trunk/arch/x86/xen/multicalls.c
+++ b/trunk/arch/x86/xen/multicalls.c
@@ -32,7 +32,11 @@
 struct mc_buffer {
 	struct multicall_entry entries[MC_BATCH];
 	u64 args[MC_ARGS];
-	unsigned mcidx, argidx;
+	struct callback {
+		void (*fn)(void *);
+		void *data;
+	} callbacks[MC_BATCH];
+	unsigned mcidx, argidx, cbidx;
 };
 
 static DEFINE_PER_CPU(struct mc_buffer, mc_buffer);
@@ -43,6 +47,7 @@ void xen_mc_flush(void)
 	struct mc_buffer *b = &__get_cpu_var(mc_buffer);
 	int ret = 0;
 	unsigned long flags;
+	int i;
 
 	BUG_ON(preemptible());
 
@@ -51,8 +56,6 @@ void xen_mc_flush(void)
 	local_irq_save(flags);
 
 	if (b->mcidx) {
-		int i;
-
 		if (HYPERVISOR_multicall(b->entries, b->mcidx) != 0)
 			BUG();
 		for (i = 0; i < b->mcidx; i++)
@@ -65,6 +68,13 @@ void xen_mc_flush(void)
 
 	local_irq_restore(flags);
 
+	for(i = 0; i < b->cbidx; i++) {
+		struct callback *cb = &b->callbacks[i];
+
+		(*cb->fn)(cb->data);
+	}
+	b->cbidx = 0;
+
 	BUG_ON(ret);
 }
 
@@ -88,3 +98,16 @@ struct multicall_space __xen_mc_entry(size_t args)
 
 	return ret;
 }
+
+void xen_mc_callback(void (*fn)(void *), void *data)
+{
+	struct mc_buffer *b = &__get_cpu_var(mc_buffer);
+	struct callback *cb;
+
+	if (b->cbidx == MC_BATCH)
+		xen_mc_flush();
+
+	cb = &b->callbacks[b->cbidx++];
+	cb->fn = fn;
+	cb->data = data;
+}
diff --git a/trunk/arch/x86/xen/multicalls.h b/trunk/arch/x86/xen/multicalls.h
index 5d96a5fa210c..8bae996d99a3 100644
--- a/trunk/arch/x86/xen/multicalls.h
+++ b/trunk/arch/x86/xen/multicalls.h
@@ -42,4 +42,7 @@ static inline void xen_mc_issue(unsigned mode)
 	local_irq_restore(x86_read_percpu(xen_mc_irq_flags));
 }
 
+/* Set up a callback to be called when the current batch is flushed */
+void xen_mc_callback(void (*fn)(void *), void *data);
+
 #endif /* _XEN_MULTICALLS_H */