tile: SMP: Remove call to ipi_call_lock()/ipi_call_unlock()

ipi_call_lock/unlock() lock resp. unlock call_function.lock. This lock
protects only the call_function data structure itself, but it's
completely unrelated to cpu_online_mask. The mask to which the IPIs
are sent is calculated before call_function.lock is taken in
smp_call_function_many(), so the locking around set_cpu_online() is
pointless and can be removed.

[ tglx: Massaged changelog ]

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Cc: ralf@linux-mips.org
Cc: sshtylyov@mvista.com
Cc: david.daney@cavium.com
Cc: nikunj@linux.vnet.ibm.com
Cc: paulmck@linux.vnet.ibm.com
Cc: axboe@kernel.dk
Cc: peterz@infradead.org
Cc: Chris Metcalf <cmetcalf@tilera.com>
Link: http://lkml.kernel.org/r/1338275765-3217-6-git-send-email-yong.zhang0@gmail.com
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Yong Zhang 2012-05-29 15:16:00 +08:00 committed by Thomas Gleixner
parent 46ce7fbfdb
commit 8efdfc3a4e

View File

@ -198,17 +198,7 @@ void __cpuinit online_secondary(void)
notify_cpu_starting(smp_processor_id());
/*
* We need to hold call_lock, so there is no inconsistency
* between the time smp_call_function() determines number of
* IPI recipients, and the time when the determination is made
* for which cpus receive the IPI. Holding this
* lock helps us to not include this cpu in a currently in progress
* smp_call_function().
*/
ipi_call_lock();
set_cpu_online(smp_processor_id(), 1);
ipi_call_unlock();
__get_cpu_var(cpu_state) = CPU_ONLINE;
/* Set up tile-specific state for this cpu. */