Re: [PATCH v2 for-7.1 7/9] nbd: move s->state under requests_lock

[Eric Blake]

On Thu, Apr 14, 2022 at 07:57:54PM +0200, Paolo Bonzini wrote:
> Remove the confusing, and most likely wrong, atomics.  The only function
> that used to be somewhat in a hot path was nbd_client_connected(),
> but it is not anymore after the previous patches.
> 
> The same logic is used both to check if a request had to be reissued
> and also in nbd_reconnecting_attempt().  The former cases are outside
> requests_lock, while nbd_reconnecting_attempt() does have the lock,
> therefore the two have been separated in the previous commit.
> nbd_client_will_reconnect() can simply take s->requests_lock, while
> nbd_reconnecting_attempt() can inline the access now that no
> complicated atomics are involved.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  block/nbd.c | 78 ++++++++++++++++++++++++++++-------------------------
>  1 file changed, 41 insertions(+), 37 deletions(-)
>

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
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