[PATCH] x86_64: Remove the broadcast options that were added for cpuhotplug

Will be obsolete with physflat.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/arch/x86_64/kernel/genapic_flat.c b/arch/x86_64/kernel/genapic_flat.c
index 2828469..fdfa15f 100644 (file)
--- a/arch/x86_64/kernel/genapic_flat.c
+++ b/arch/x86_64/kernel/genapic_flat.c
@@ -7,8 +7,6 @@
  * Hacked for x86-64 by James Cleverdon from i386 architecture code by
  * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
  * James Cleverdon.
  * Hacked for x86-64 by James Cleverdon from i386 architecture code by
  * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
  * James Cleverdon.

- * Ashok Raj <ashok.raj@intel.com>
- *     Removed IPI broadcast shortcut to support CPU hotplug

  */
 #include <linux/config.h>
 #include <linux/threads.h>
  */
 #include <linux/config.h>
 #include <linux/threads.h>


@@ -20,47 +18,6 @@
 #include <asm/smp.h>
 #include <asm/ipi.h>
 
 #include <asm/smp.h>
 #include <asm/ipi.h>
 

-/*
- * The following permit choosing broadcast IPI shortcut v.s sending IPI only
- * to online cpus via the send_IPI_mask varient.
- * The mask version is my preferred option, since it eliminates a lot of
- * other extra code that would need to be written to cleanup intrs sent
- * to a CPU while offline.
- *
- * Sending broadcast introduces lots of trouble in CPU hotplug situations.
- * These IPI's are delivered to cpu's irrespective of their offline status
- * and could pickup stale intr data when these CPUS are turned online.
- *
- * Not using broadcast is a cleaner approach IMO, but Andi Kleen disagrees with
- * the idea of not using broadcast IPI's anymore. Hence the run time check
- * is introduced, on his request so we can choose an alternate mechanism.
- *
- * Initial wacky performance tests that collect cycle counts show
- * no increase in using mask v.s broadcast version. In fact they seem
- * identical in terms of cycle counts.
- *
- * if we need to use broadcast, we need to do the following.
- *
- * cli;
- * hold call_lock;
- * clear any pending IPI, just ack and clear all pending intr
- * set cpu_online_map;
- * release call_lock;
- * sti;
- *
- * The complicated dummy irq processing shown above is not required if
- * we didnt sent IPI's to wrong CPU's in the first place.
- *
- * - Ashok Raj <ashok.raj@intel.com>
- */
-#ifdef CONFIG_HOTPLUG_CPU
-#define DEFAULT_SEND_IPI       (1)
-#else
-#define DEFAULT_SEND_IPI       (0)
-#endif
-
-static int no_broadcast=DEFAULT_SEND_IPI;
-

 static cpumask_t flat_target_cpus(void)
 {
        return cpu_online_map;
 static cpumask_t flat_target_cpus(void)
 {
        return cpu_online_map;


@@ -119,37 +76,15 @@ static void flat_send_IPI_mask(cpumask_t cpumask, int vector)
        local_irq_restore(flags);
 }
 
        local_irq_restore(flags);
 }
 

-static inline void __local_flat_send_IPI_allbutself(int vector)
-{
-       if (no_broadcast) {
-               cpumask_t mask = cpu_online_map;
-               int this_cpu = get_cpu();
-
-               cpu_clear(this_cpu, mask);
-               flat_send_IPI_mask(mask, vector);
-               put_cpu();
-       }
-       else
-               __send_IPI_shortcut(APIC_DEST_ALLBUT, vector, APIC_DEST_LOGICAL);
-}
-
-static inline void __local_flat_send_IPI_all(int vector)
-{
-       if (no_broadcast)
-               flat_send_IPI_mask(cpu_online_map, vector);
-       else
-               __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL);
-}
-

 static void flat_send_IPI_allbutself(int vector)
 {
        if (((num_online_cpus()) - 1) >= 1)
 static void flat_send_IPI_allbutself(int vector)
 {
        if (((num_online_cpus()) - 1) >= 1)

-               __local_flat_send_IPI_allbutself(vector);
+               __send_IPI_shortcut(APIC_DEST_ALLBUT, vector,APIC_DEST_LOGICAL);

 }
 
 static void flat_send_IPI_all(int vector)
 {
 }
 
 static void flat_send_IPI_all(int vector)
 {

-       __local_flat_send_IPI_all(vector);
+       __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL);

 }
 
 static int flat_apic_id_registered(void)
 }
 
 static int flat_apic_id_registered(void)


@@ -170,16 +105,6 @@ static unsigned int phys_pkg_id(int index_msb)
        return ((ebx >> 24) & 0xFF) >> index_msb;
 }
 
        return ((ebx >> 24) & 0xFF) >> index_msb;
 }
 

-static __init int no_ipi_broadcast(char *str)
-{
-       get_option(&str, &no_broadcast);
-       printk ("Using %s mode\n", no_broadcast ? "No IPI Broadcast" :
-                                                                                       "IPI Broadcast");
-       return 1;
-}
-
-__setup("no_ipi_broadcast", no_ipi_broadcast);
-

 struct genapic apic_flat =  {
        .name = "flat",
        .int_delivery_mode = dest_LowestPrio,
 struct genapic apic_flat =  {
        .name = "flat",
        .int_delivery_mode = dest_LowestPrio,


@@ -194,12 +119,3 @@ struct genapic apic_flat =  {
        .cpu_mask_to_apicid = flat_cpu_mask_to_apicid,
        .phys_pkg_id = phys_pkg_id,
 };
        .cpu_mask_to_apicid = flat_cpu_mask_to_apicid,
        .phys_pkg_id = phys_pkg_id,
 };

-
-static int __init print_ipi_mode(void)
-{
-       printk ("Using IPI %s mode\n", no_broadcast ? "No-Shortcut" :
-                                                                                       "Shortcut");
-       return 0;
-}
-
-late_initcall(print_ipi_mode);