Re: [PATCH] KEYS: Reduce smp_mb() calls in key_put()

From: Herbert Xu
Date: Sat May 03 2025 - 20:36:53 EST


On Sat, May 03, 2025 at 11:19:21PM +0100, David Howells wrote:
>
> Possibly we only need smp_mb() in the IN_QUOTA branch in key_put().

Just change the smp_mb to smp_mb__before_atomic, at least on x86
it just disappears because set_bit is already a serialising operation.

Or even better, reverse the FINAL_PUT bit and call it ALIVE, so
that you can use test_bit_acquire and clear_bit_unlock.

Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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