tree fc9a10cde7d91afb4add41d1c4c2e7ce797c9a5b
parent 1b929c02afd37871d5afb9d498426f83432e71c2
author Parav Pandit <parav@nvidia.com> 1666901400 +0300
committer Paul E. McKenney <paulmck@kernel.org> 1672807624 -0800

locking/memory-barriers.txt: Improve documentation for writel() example

The cited commit describes that when using writel(), explicit wmb()
is not needed. wmb() is an expensive barrier. writel() uses the needed
platform specific barrier instead of wmb().

writeX() section of "KERNEL I/O BARRIER EFFECTS" already describes
ordering of I/O accessors with MMIO writes.

Hence add the comment for pseudo code of writel() and remove confusing
text around writel() and wmb().

commit 5846581e3563 ("locking/memory-barriers.txt: Fix broken DMA vs. MMIO ordering example")

Co-developed-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>