---

yaml
---
r: 175855
b: refs/heads/master
c: 49bd364
h: refs/heads/master
i:
  175853: 3dc6bde
  175851: a7d9c0a
  175847: 0f8b269
  175839: 31de0ed
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 275a64f6040073254fa15eaf6e4e720f77d531d6
+refs/heads/master: 49bd3647134ea47420067aea8d1401e722bf2aac

trunk/arch/powerpc/platforms/pseries/xics.c

@@ -20,6 +20,7 @@
 #include <linux/cpu.h>
 #include <linux/msi.h>
 #include <linux/of.h>
+#include <linux/percpu.h>
 
 #include <asm/firmware.h>
 #include <asm/io.h>
@@ -46,6 +47,12 @@ static struct irq_host *xics_host;
  */
 #define IPI_PRIORITY		4
 
+/* The least favored priority */
+#define LOWEST_PRIORITY		0xFF
+
+/* The number of priorities defined above */
+#define MAX_NUM_PRIORITIES	3
+
 static unsigned int default_server = 0xFF;
 static unsigned int default_distrib_server = 0;
 static unsigned int interrupt_server_size = 8;
@@ -56,6 +63,12 @@ static int ibm_set_xive;
 static int ibm_int_on;
 static int ibm_int_off;
 
+struct xics_cppr {
+	unsigned char stack[MAX_NUM_PRIORITIES];
+	int index;
+};
+
+static DEFINE_PER_CPU(struct xics_cppr, xics_cppr);
 
 /* Direct hardware low level accessors */
 
@@ -284,6 +297,19 @@ static inline unsigned int xics_xirr_vector(unsigned int xirr)
 	return xirr & 0x00ffffff;
 }
 
+static void push_cppr(unsigned int vec)
+{
+	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
+
+	if (WARN_ON(os_cppr->index >= MAX_NUM_PRIORITIES - 1))
+		return;
+
+	if (vec == XICS_IPI)
+		os_cppr->stack[++os_cppr->index] = IPI_PRIORITY;
+	else
+		os_cppr->stack[++os_cppr->index] = DEFAULT_PRIORITY;
+}
+
 static unsigned int xics_get_irq_direct(void)
 {
 	unsigned int xirr = direct_xirr_info_get();
@@ -294,8 +320,10 @@ static unsigned int xics_get_irq_direct(void)
 		return NO_IRQ;
 
 	irq = irq_radix_revmap_lookup(xics_host, vec);
-	if (likely(irq != NO_IRQ))
+	if (likely(irq != NO_IRQ)) {
+		push_cppr(vec);
 		return irq;
+	}
 
 	/* We don't have a linux mapping, so have rtas mask it. */
 	xics_mask_unknown_vec(vec);
@@ -315,8 +343,10 @@ static unsigned int xics_get_irq_lpar(void)
 		return NO_IRQ;
 
 	irq = irq_radix_revmap_lookup(xics_host, vec);
-	if (likely(irq != NO_IRQ))
+	if (likely(irq != NO_IRQ)) {
+		push_cppr(vec);
 		return irq;
+	}
 
 	/* We don't have a linux mapping, so have RTAS mask it. */
 	xics_mask_unknown_vec(vec);
@@ -326,20 +356,30 @@ static unsigned int xics_get_irq_lpar(void)
 	return NO_IRQ;
 }
 
+static unsigned char pop_cppr(void)
+{
+	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
+
+	if (WARN_ON(os_cppr->index < 1))
+		return LOWEST_PRIORITY;
+
+	return os_cppr->stack[--os_cppr->index];
+}
+
 static void xics_eoi_direct(unsigned int virq)
 {
 	unsigned int irq = (unsigned int)irq_map[virq].hwirq;
 
 	iosync();
-	direct_xirr_info_set((0xff << 24) | irq);
+	direct_xirr_info_set((pop_cppr() << 24) | irq);
 }
 
 static void xics_eoi_lpar(unsigned int virq)
 {
 	unsigned int irq = (unsigned int)irq_map[virq].hwirq;
 
 	iosync();
-	lpar_xirr_info_set((0xff << 24) | irq);
+	lpar_xirr_info_set((pop_cppr() << 24) | irq);
 }
 
 static int xics_set_affinity(unsigned int virq, const struct cpumask *cpumask)
@@ -746,6 +786,12 @@ void __init xics_init_IRQ(void)
 
 static void xics_set_cpu_priority(unsigned char cppr)
 {
+	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
+
+	BUG_ON(os_cppr->index != 0);
+
+	os_cppr->stack[os_cppr->index] = cppr;
+
 	if (firmware_has_feature(FW_FEATURE_LPAR))
 		lpar_cppr_info(cppr);
 	else
@@ -772,7 +818,7 @@ static void xics_set_cpu_giq(unsigned int gserver, unsigned int join)
 
 void xics_setup_cpu(void)
 {
-	xics_set_cpu_priority(0xff);
+	xics_set_cpu_priority(LOWEST_PRIORITY);
 
 	xics_set_cpu_giq(default_distrib_server, 1);
 }