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Date:   Wed, 22 Mar 2023 22:08:43 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Pavan Chebbi <pavan.chebbi@broadcom.com>
Cc:     davem@davemloft.net, netdev@vger.kernel.org, edumazet@google.com,
        pabeni@redhat.com, willemb@google.com, alexander.duyck@gmail.com
Subject: Re: [PATCH net-next 1/3] net: provide macros for commonly copied
 lockless queue stop/wake code
Message-ID: <20230322220843.6db66d98@kernel.org>
In-Reply-To: <CALs4sv3O73a+KT8wbQvFnGFj7Rzxbxz07j79sUWB4BybMSHDXg@mail.gmail.com>
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On Thu, 23 Mar 2023 10:23:32 +0530 Pavan Chebbi wrote:
> > +               /* We need to check again in a case another             \
> > +                * CPU has just made room available.                    \
> > +                */                                                     \
> > +               if (likely(get_desc < start_thrs)) {                    \  
> 
> I am only curious to understand why initializing _res with likely
> result and having a condition to cover only the unlikely case, would
> not be better.
> As in:
>     int _res = 0;
>     if (unlikely(get_desc >= start_thrs) {
>         start_queue()
>         _res = -1
>     }

I don't think it matters.