On 10/30/24 1:11 PM, Keith Busch wrote:
On Wed, Oct 30, 2024 at 05:46:58AM +0100, Christoph Hellwig wrote:
On Tue, Oct 29, 2024 at 10:25:11AM -0700, Bart Van Assche wrote:
+}
bitmap_copy() is not atomic. Shouldn't the bitmap_copy() call be
serialized against the code that tests bits in bdev->write_hint_mask?
It needs something. I actually pointed that out last round, but forgot
about it again this time :)
I disagree. Whether we serialize it or not, writes in flight will either
think it can write or it won't. There's no point adding any overhead to
the IO path for this as you can't stop ending up with inflight writes
using the tag you're trying to turn off.
Shouldn't the request queue be frozen while this write_hint_mask bitmap
is modified, just like the request queue is frozen while queue limits
are updated? This change wouldn't add any additional overhead to the I/O
path.
Thanks,
Bart.
