From 86ef5c9a8edd78e6bf92879f32329d89b2d55b5a Mon Sep 17 00:00:00 2001 From: Gautham R Shenoy Date: Fri, 25 Jan 2008 21:08:02 +0100 Subject: cpu-hotplug: replace lock_cpu_hotplug() with get_online_cpus() Replace all lock_cpu_hotplug/unlock_cpu_hotplug from the kernel and use get_online_cpus and put_online_cpus instead as it highlights the refcount semantics in these operations. The new API guarantees protection against the cpu-hotplug operation, but it doesn't guarantee serialized access to any of the local data structures. Hence the changes needs to be reviewed. In case of pseries_add_processor/pseries_remove_processor, use cpu_maps_update_begin()/cpu_maps_update_done() as we're modifying the cpu_present_map there. Signed-off-by: Gautham R Shenoy Signed-off-by: Ingo Molnar --- arch/powerpc/platforms/pseries/hotplug-cpu.c | 8 ++++---- arch/powerpc/platforms/pseries/rtasd.c | 8 ++++---- 2 files changed, 8 insertions(+), 8 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c index 412e6b42986..c4ad54e0f28 100644 --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c @@ -153,7 +153,7 @@ static int pseries_add_processor(struct device_node *np) for (i = 0; i < nthreads; i++) cpu_set(i, tmp); - lock_cpu_hotplug(); + cpu_maps_update_begin(); BUG_ON(!cpus_subset(cpu_present_map, cpu_possible_map)); @@ -190,7 +190,7 @@ static int pseries_add_processor(struct device_node *np) } err = 0; out_unlock: - unlock_cpu_hotplug(); + cpu_maps_update_done(); return err; } @@ -211,7 +211,7 @@ static void pseries_remove_processor(struct device_node *np) nthreads = len / sizeof(u32); - lock_cpu_hotplug(); + cpu_maps_update_begin(); for (i = 0; i < nthreads; i++) { for_each_present_cpu(cpu) { if (get_hard_smp_processor_id(cpu) != intserv[i]) @@ -225,7 +225,7 @@ static void pseries_remove_processor(struct device_node *np) printk(KERN_WARNING "Could not find cpu to remove " "with physical id 0x%x\n", intserv[i]); } - unlock_cpu_hotplug(); + cpu_maps_update_done(); } static int pseries_smp_notifier(struct notifier_block *nb, diff --git a/arch/powerpc/platforms/pseries/rtasd.c b/arch/powerpc/platforms/pseries/rtasd.c index 73401c82011..e3078ce4151 100644 --- a/arch/powerpc/platforms/pseries/rtasd.c +++ b/arch/powerpc/platforms/pseries/rtasd.c @@ -382,7 +382,7 @@ static void do_event_scan_all_cpus(long delay) { int cpu; - lock_cpu_hotplug(); + get_online_cpus(); cpu = first_cpu(cpu_online_map); for (;;) { set_cpus_allowed(current, cpumask_of_cpu(cpu)); @@ -390,15 +390,15 @@ static void do_event_scan_all_cpus(long delay) set_cpus_allowed(current, CPU_MASK_ALL); /* Drop hotplug lock, and sleep for the specified delay */ - unlock_cpu_hotplug(); + put_online_cpus(); msleep_interruptible(delay); - lock_cpu_hotplug(); + get_online_cpus(); cpu = next_cpu(cpu, cpu_online_map); if (cpu == NR_CPUS) break; } - unlock_cpu_hotplug(); + put_online_cpus(); } static int rtasd(void *unused) -- cgit v1.2.3