I spotted the weird-looking pattern of:
atomic_set(atomic_load() <some operation> N)
in a few palces and one variable in the graph-lock code which was used with
atomics except for a single case, which also seemed suspicious.
I'm not sure if there are any known compiler-optimizations or ordering
semantics already ensuring that these operations are indeed working correctly
atomically, so I thought I'd point them out and ask about it by sending
patches.
In patch 2 the ordering is changed (see the note in its mail)
Wolfgang Bumiller (2):
graph-lock: make sure reader_count access is atomic
atomics: replace fetch-use-store with direct atomic operations
block/graph-lock.c | 8 +++-----
util/aio-posix.c | 3 +--
util/aio-win32.c | 3 +--
util/async.c | 2 +-
4 files changed, 6 insertions(+), 10 deletions(-)
--
2.39.2
