RE: [PATCH v2 2/5] venus: Make sys_error flag an atomic bitops

From: David Laight
Date: Wed Jun 09 2021 - 12:03:13 EST


From: Stanimir Varbanov <stanimir.varbanov@xxxxxxxxxx>
> Sent: 08 June 2021 12:42
>
> Make the sys_error flag an atomic bitops in order to avoid
> locking in sys_error readers.

I don't think that makes any difference at all.

It is only atomic w.r.t other bitops in the same bitmap.
Even if it contained the fullest memory barrier you can
imagine the result of test_bit() is immediately stale.

David

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