[RFC PATCH v1 0/2] Deduplicating RISCV cmpxchg.h macros

[Leonardo Bras]

While studying riscv's cmpxchg.h file, I got really interested in
understanding how RISCV asm implemented the different versions of
{cmp,}xchg.

When I understood the pattern, it made sense for me to remove the
duplications and create macros to make it easier to understand what exactly
changes between the versions: Instruction sufixes & barriers.

Thanks!
Leo

Changes since RFCv3:
- Squashed the 6 original patches in 2: one for cmpxchg and one for xchg
https://lore.kernel.org/all/20230404163741.2762165-1-leobras@xxxxxxxxxx/

Changes since RFCv2:
- Fixed  macros that depend on having a local variable with a magic name
- Previous cast to (long) is now only applied on 4-bytes cmpxchg
https://lore.kernel.org/all/20230321074249.2221674-1-leobras@xxxxxxxxxx/

Changes since RFCv1:
- Fixed patch 4/6 suffix from 'w.aqrl' to '.w.aqrl', to avoid build error
https://lore.kernel.org/all/20230318080059.1109286-1-leobras@xxxxxxxxxx/

Leonardo Bras (2):
  riscv/cmpxchg: Deduplicate cmpxchg() asm and macros
  riscv/cmpxchg: Deduplicate xchg() asm functions

 arch/riscv/include/asm/cmpxchg.h | 319 +++++++------------------------
 1 file changed, 67 insertions(+), 252 deletions(-)

-- 
2.40.0