From: Anup Patel <anup.patel@linaro.org>
Date: Mon, 25 Aug 2014 10:18:40 +0000 (+0530)
Subject: xen arm/arm64: minor improvement in smp_send_call_function_mask()
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~4506
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=95f7ed9abb71b897c70893aaa9c4f413aa4b487e;p=xen.git

xen arm/arm64: minor improvement in smp_send_call_function_mask()

Currently, smp_send_call_function_mask() function implemented
by xen arm/arm64 will use IPI to call function on current CPU.

This means that current smp_send_call_function_mask() will do
the following on current CPU:
Trigger SGI for current CPU => Xen takes interrupt on current CPU
=> IPI interrupt handler will call smp_call_function_interrupt()

This patch improves the above by straight away calling
smp_call_function_interrupt() for current CPU. This is very
similar to smp_send_call_function_mask() implemented by Xen x86.

Signed-off-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Acked-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
---

diff --git a/xen/arch/arm/smp.c b/xen/arch/arm/smp.c
index 30203b8883..917d490ce7 100644
--- a/xen/arch/arm/smp.c
+++ b/xen/arch/arm/smp.c
@@ -19,7 +19,18 @@ void smp_send_event_check_mask(const cpumask_t *mask)
 
 void smp_send_call_function_mask(const cpumask_t *mask)
 {
-    send_SGI_mask(mask, GIC_SGI_CALL_FUNCTION);
+    cpumask_t target_mask;
+
+    cpumask_andnot(&target_mask, mask, cpumask_of(smp_processor_id()));
+
+    send_SGI_mask(&target_mask, GIC_SGI_CALL_FUNCTION);
+
+    if ( cpumask_test_cpu(smp_processor_id(), mask) )
+    {
+        local_irq_disable();
+        smp_call_function_interrupt();
+        local_irq_enable();
+    }
 }
 
 /*