X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=arch%2Fx86_64%2Fkernel%2Fgenapic.c;h=b007433f96bbc540b2d71ef9b50f81d8349a2174;hb=0a01707b289853f56d1c000057b27e243c039722;hp=b1c144f73149854da5e9bb277e4309e281b60ba3;hpb=344a076110f4ecb16ea6d286b63be696604982ed;p=powerpc.git

diff --git a/arch/x86_64/kernel/genapic.c b/arch/x86_64/kernel/genapic.c
index b1c144f731..b007433f96 100644
--- a/arch/x86_64/kernel/genapic.c
+++ b/arch/x86_64/kernel/genapic.c
@@ -8,7 +8,6 @@
  * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
  * James Cleverdon.
  */
-#include <linux/config.h>
 #include <linux/threads.h>
 #include <linux/cpumask.h>
 #include <linux/string.h>
@@ -34,7 +33,7 @@ extern struct genapic apic_flat;
 extern struct genapic apic_physflat;
 
 struct genapic *genapic = &apic_flat;
-
+struct genapic *genapic_force;
 
 /*
  * Check the APIC IDs in bios_cpu_apicid and choose the APIC mode.
@@ -45,7 +44,14 @@ void __init clustered_apic_check(void)
 	u8 clusters, max_cluster;
 	u8 id;
 	u8 cluster_cnt[NUM_APIC_CLUSTERS];
-	int num_cpus = 0;
+	int max_apic = 0;
+
+	/* genapic selection can be forced because of certain quirks.
+	 */
+	if (genapic_force) {
+		genapic = genapic_force;
+		goto print;
+	}
 
 #if defined(CONFIG_ACPI)
 	/*
@@ -64,14 +70,15 @@ void __init clustered_apic_check(void)
 		id = bios_cpu_apicid[i];
 		if (id == BAD_APICID)
 			continue;
-		num_cpus++;
+		if (id > max_apic)
+			max_apic = id;
 		cluster_cnt[APIC_CLUSTERID(id)]++;
 	}
 
 	/* Don't use clustered mode on AMD platforms. */
  	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
 		genapic = &apic_physflat;
-#ifndef CONFIG_CPU_HOTPLUG
+#ifndef CONFIG_HOTPLUG_CPU
 		/* In the CPU hotplug case we cannot use broadcast mode
 		   because that opens a race when a CPU is removed.
 		   Stay at physflat mode in this case.
@@ -79,7 +86,7 @@ void __init clustered_apic_check(void)
 		   we have ACPI platform support for CPU hotplug
 		   we should detect hotplug capablity from ACPI tables and
 		   only do this when really needed. -AK */
-		if (num_cpus <= 8)
+		if (max_apic <= 8)
 			genapic = &apic_flat;
 #endif
  		goto print;
@@ -103,9 +110,14 @@ void __init clustered_apic_check(void)
 	 * (We don't use lowest priority delivery + HW APIC IRQ steering, so
 	 * can ignore the clustered logical case and go straight to physical.)
 	 */
-	if (clusters <= 1 && max_cluster <= 8 && cluster_cnt[0] == max_cluster)
+	if (clusters <= 1 && max_cluster <= 8 && cluster_cnt[0] == max_cluster) {
+#ifdef CONFIG_HOTPLUG_CPU
+		/* Don't use APIC shortcuts in CPU hotplug to avoid races */
+		genapic = &apic_physflat;
+#else
 		genapic = &apic_flat;
-	else
+#endif
+	} else
 		genapic = &apic_cluster;
 
 print: