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 --- drivers/lguest/x86/core.c | 8 ++++---- drivers/s390/char/sclp_config.c | 4 ++-- 2 files changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers') diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c index 482aec2a963..96d0fd07c57 100644 --- a/drivers/lguest/x86/core.c +++ b/drivers/lguest/x86/core.c @@ -459,7 +459,7 @@ void __init lguest_arch_host_init(void) /* We don't need the complexity of CPUs coming and going while we're * doing this. */ - lock_cpu_hotplug(); + get_online_cpus(); if (cpu_has_pge) { /* We have a broader idea of "global". */ /* Remember that this was originally set (for cleanup). */ cpu_had_pge = 1; @@ -469,20 +469,20 @@ void __init lguest_arch_host_init(void) /* Turn off the feature in the global feature set. */ clear_bit(X86_FEATURE_PGE, boot_cpu_data.x86_capability); } - unlock_cpu_hotplug(); + put_online_cpus(); }; /*:*/ void __exit lguest_arch_host_fini(void) { /* If we had PGE before we started, turn it back on now. */ - lock_cpu_hotplug(); + get_online_cpus(); if (cpu_had_pge) { set_bit(X86_FEATURE_PGE, boot_cpu_data.x86_capability); /* adjust_pge's argument "1" means set PGE. */ on_each_cpu(adjust_pge, (void *)1, 0, 1); } - unlock_cpu_hotplug(); + put_online_cpus(); } diff --git a/drivers/s390/char/sclp_config.c b/drivers/s390/char/sclp_config.c index 5322e5e54a9..9dc77f14fa5 100644 --- a/drivers/s390/char/sclp_config.c +++ b/drivers/s390/char/sclp_config.c @@ -29,12 +29,12 @@ static void sclp_cpu_capability_notify(struct work_struct *work) struct sys_device *sysdev; printk(KERN_WARNING TAG "cpu capability changed.\n"); - lock_cpu_hotplug(); + get_online_cpus(); for_each_online_cpu(cpu) { sysdev = get_cpu_sysdev(cpu); kobject_uevent(&sysdev->kobj, KOBJ_CHANGE); } - unlock_cpu_hotplug(); + put_online_cpus(); } static void sclp_conf_receiver_fn(struct evbuf_header *evbuf) -- cgit v1.2.3