Merge HEAD from rsync://rsync.kernel.org/pub/scm/linux/kernel/git/torvalds/linux...

[pandora-kernel.git] / arch / x86_64 / kernel / smpboot.c

diff --git a/arch/x86_64/kernel/smpboot.c b/arch/x86_64/kernel/smpboot.c
index 6d23354..fa25e39 100644 (file)
--- a/arch/x86_64/kernel/smpboot.c
+++ b/arch/x86_64/kernel/smpboot.c
@@ -211,9 +211,6 @@ static __cpuinit void sync_master(void *arg)
 {
        unsigned long flags, i;
 
-       if (smp_processor_id() != 0)
-               return;
-
        go[MASTER] = 0;
 
        local_irq_save(flags);
@@ -262,7 +259,7 @@ get_delta(long *rt, long *master)
        return tcenter - best_tm;
 }
 
-static __cpuinit void sync_tsc(void)
+static __cpuinit void sync_tsc(unsigned int master)
 {
        int i, done = 0;
        long delta, adj, adjust_latency = 0;
@@ -276,9 +273,17 @@ static __cpuinit void sync_tsc(void)
        } t[NUM_ROUNDS] __cpuinitdata;
 #endif
 
+       printk(KERN_INFO "CPU %d: Syncing TSC to CPU %u.\n",
+               smp_processor_id(), master);
+
        go[MASTER] = 1;
 
-       smp_call_function(sync_master, NULL, 1, 0);
+       /* It is dangerous to broadcast IPI as cpus are coming up,
+        * as they may not be ready to accept them.  So since
+        * we only need to send the ipi to the boot cpu direct
+        * the message, and avoid the race.
+        */
+       smp_call_function_single(master, sync_master, NULL, 1, 0);
 
        while (go[MASTER])      /* wait for master to be ready */
                no_cpu_relax();
@@ -322,16 +327,14 @@ static __cpuinit void sync_tsc(void)
        printk(KERN_INFO
               "CPU %d: synchronized TSC with CPU %u (last diff %ld cycles, "
               "maxerr %lu cycles)\n",
-              smp_processor_id(), boot_cpu_id, delta, rt);
+              smp_processor_id(), master, delta, rt);
 }
 
 static void __cpuinit tsc_sync_wait(void)
 {
        if (notscsync || !cpu_has_tsc)
                return;
-       printk(KERN_INFO "CPU %d: Syncing TSC to CPU %u.\n", smp_processor_id(),
-                       boot_cpu_id);
-       sync_tsc();
+       sync_tsc(0);
 }
 
 static __init int notscsync_setup(char *s)
@@ -489,6 +492,14 @@ void __cpuinit start_secondary(void)
         */
        set_cpu_sibling_map(smp_processor_id());
 
+       /* 
+        * Wait for TSC sync to not schedule things before.
+        * We still process interrupts, which could see an inconsistent
+        * time in that window unfortunately. 
+        * Do this here because TSC sync has global unprotected state.
+        */
+       tsc_sync_wait();
+
        /*
         * We need to hold call_lock, so there is no inconsistency
         * between the time smp_call_function() determines number of
@@ -506,13 +517,6 @@ void __cpuinit start_secondary(void)
        per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
        unlock_ipi_call_lock();
 
-       mb();
-
-       /* Wait for TSC sync to not schedule things before.
-          We still process interrupts, which could see an inconsistent
-          time in that window unfortunately. */
-       tsc_sync_wait();
-
        cpu_idle();
 }