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 <ego@in.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/net/core/flow.c b/net/core/flow.c
index 3ed2b4b..6489f4e 100644
--- a/net/core/flow.c
+++ b/net/core/flow.c
@@ -293,7 +293,7 @@
static DEFINE_MUTEX(flow_flush_sem);
/* Don't want cpus going down or up during this. */
- lock_cpu_hotplug();
+ get_online_cpus();
mutex_lock(&flow_flush_sem);
atomic_set(&info.cpuleft, num_online_cpus());
init_completion(&info.completion);
@@ -305,7 +305,7 @@
wait_for_completion(&info.completion);
mutex_unlock(&flow_flush_sem);
- unlock_cpu_hotplug();
+ put_online_cpus();
}
static void __devinit flow_cache_cpu_prepare(int cpu)