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/x86/kernel/cpu/mtrr/main.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/x86/kernel/cpu/mtrr/main.c') diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index 3b20613325dc..beb45c9c0835 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -349,7 +349,7 @@ int mtrr_add_page(unsigned long base, unsigned long size, replace = -1; /* No CPU hotplug when we change MTRR entries */ - lock_cpu_hotplug(); + get_online_cpus(); /* Search for existing MTRR */ mutex_lock(&mtrr_mutex); for (i = 0; i < num_var_ranges; ++i) { @@ -405,7 +405,7 @@ int mtrr_add_page(unsigned long base, unsigned long size, error = i; out: mutex_unlock(&mtrr_mutex); - unlock_cpu_hotplug(); + put_online_cpus(); return error; } @@ -495,7 +495,7 @@ int mtrr_del_page(int reg, unsigned long base, unsigned long size) max = num_var_ranges; /* No CPU hotplug when we change MTRR entries */ - lock_cpu_hotplug(); + get_online_cpus(); mutex_lock(&mtrr_mutex); if (reg < 0) { /* Search for existing MTRR */ @@ -536,7 +536,7 @@ int mtrr_del_page(int reg, unsigned long base, unsigned long size) error = reg; out: mutex_unlock(&mtrr_mutex); - unlock_cpu_hotplug(); + put_online_cpus(); return error; } /** -- cgit v1.2.3-59-g8ed1b