linux/arch/xtensa
Mark Rutland 6aa7de0591 locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.

However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:

----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()

// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch

virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-25 11:01:08 +02:00
..
boot Xtensa improvements for v4.11: 2017-03-03 16:17:55 -08:00
configs xtensa: add default memmap and mmio32native options to defconfigs 2016-09-20 20:43:24 -07:00
include locking/arch: Remove dummy arch_{read,spin,write}_lock_flags() implementations 2017-10-10 11:50:19 +02:00
kernel xtensa: Mark _stext and _end as char-arrays, not single char variables 2017-08-10 16:28:52 +02:00
lib xtensa: get rid of zeroing, use RAW_COPY_USER 2017-03-28 18:24:07 -04:00
mm xtensa: mm/cache: add missing EXPORT_SYMBOLs 2017-08-01 11:17:35 -07:00
oprofile xtensa: move oprofile stack tracing to stacktrace.c 2015-08-17 07:32:49 +03:00
platforms locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() 2017-10-25 11:01:08 +02:00
variants xtensa: Added Cadence CSP kernel configuration for Xtensa 2016-09-09 18:39:09 -07:00
Kconfig drivers: dma-mapping: allow dma_common_mmap() for NOMMU 2017-06-30 10:03:07 -07:00
Kconfig.debug xtensa: disable link optimization 2014-12-15 23:47:24 -08:00
Makefile xtensa: clean up bootable image build targets 2017-03-01 12:32:50 -08:00