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staging: vchiq_util: get rid of unneeded memory barriers

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All the memory operations featured in this file modify/access memory
that is only accessed by the CPU. So we can assume that all the memory
barrier handling done by the completion routines is good enough for us.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Acked-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Nicolas Saenz Julienne 2018-11-20 15:53:47 +01:00 committed by Greg Kroah-Hartman
parent f27e47bc6b
commit 96f3371272
1 changed files with 0 additions and 32 deletions
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32
drivers/staging/vc04_services/interface/vchiq_arm/vchiq_util.c
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@ -84,20 +84,7 @@ void vchiu_queue_push(VCHIU_QUEUE_T *queue, VCHIQ_HEADER_T *header)
flush_signals(current);
}
/*
* Write to queue->storage must be visible after read from
* queue->read
*/
smp_mb();
queue->storage[queue->write & (queue->size - 1)] = header;
/*
* Write to queue->storage must be visible before write to
* queue->write
*/
smp_wmb();
queue->write++;
complete(&queue->push);
@ -112,12 +99,6 @@ VCHIQ_HEADER_T *vchiu_queue_peek(VCHIU_QUEUE_T *queue)
complete(&queue->push); // We haven't removed anything from the queue.
/*
* Read from queue->storage must be visible after read from
* queue->write
*/
smp_rmb();
return queue->storage[queue->read & (queue->size - 1)];
}
@ -130,20 +111,7 @@ VCHIQ_HEADER_T *vchiu_queue_pop(VCHIU_QUEUE_T *queue)
flush_signals(current);
}
/*
* Read from queue->storage must be visible after read from
* queue->write
*/
smp_rmb();
header = queue->storage[queue->read & (queue->size - 1)];
/*
* Read from queue->storage must be visible before write to
* queue->read
*/
smp_mb();
queue->read++;
complete(&queue->pop);