diff options
Diffstat (limited to 'arch/i386/kernel/smpboot.c')
| -rw-r--r-- | arch/i386/kernel/smpboot.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c index 825b2b4ca721..bd0ca5c9f053 100644 --- a/arch/i386/kernel/smpboot.c +++ b/arch/i386/kernel/smpboot.c @@ -257,7 +257,7 @@ static void __init synchronize_tsc_bp (void) * all APs synchronize but they loop on '== num_cpus' */ while (atomic_read(&tsc_count_start) != num_booting_cpus()-1) - mb(); + cpu_relax(); atomic_set(&tsc_count_stop, 0); wmb(); /* @@ -276,7 +276,7 @@ static void __init synchronize_tsc_bp (void) * Wait for all APs to leave the synchronization point: */ while (atomic_read(&tsc_count_stop) != num_booting_cpus()-1) - mb(); + cpu_relax(); atomic_set(&tsc_count_start, 0); wmb(); atomic_inc(&tsc_count_stop); @@ -333,19 +333,21 @@ static void __init synchronize_tsc_ap (void) * this gets called, so we first wait for the BP to * finish SMP initialization: */ - while (!atomic_read(&tsc_start_flag)) mb(); + while (!atomic_read(&tsc_start_flag)) + cpu_relax(); for (i = 0; i < NR_LOOPS; i++) { atomic_inc(&tsc_count_start); while (atomic_read(&tsc_count_start) != num_booting_cpus()) - mb(); + cpu_relax(); rdtscll(tsc_values[smp_processor_id()]); if (i == NR_LOOPS-1) write_tsc(0, 0); atomic_inc(&tsc_count_stop); - while (atomic_read(&tsc_count_stop) != num_booting_cpus()) mb(); + while (atomic_read(&tsc_count_stop) != num_booting_cpus()) + cpu_relax(); } } #undef NR_LOOPS @@ -1433,7 +1435,7 @@ int __devinit __cpu_up(unsigned int cpu) /* Unleash the CPU! */ cpu_set(cpu, smp_commenced_mask); while (!cpu_isset(cpu, cpu_online_map)) - mb(); + cpu_relax(); return 0; } |