Re: [net-next] net: mvpp2: fix interrupt mask/unmask skip condition

From: Russell King - ARM Linux admin
Date: Thu Feb 11 2021 - 12:49:44 EST


On Thu, Feb 11, 2021 at 05:13:19PM +0200, stefanc@xxxxxxxxxxx wrote:
> From: Stefan Chulski <stefanc@xxxxxxxxxxx>
>
> The condition should be skipped if CPU ID equal to nthreads.
> The patch doesn't fix any actual issue since
> nthreads = min_t(unsigned int, num_present_cpus(), MVPP2_MAX_THREADS).
> On all current Armada platforms, the number of CPU's is
> less than MVPP2_MAX_THREADS.
>
> Fixes: e531f76757eb ("net: mvpp2: handle cases where more CPUs are available than s/w threads")
> Reported-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
> Signed-off-by: Stefan Chulski <stefanc@xxxxxxxxxxx>

Reviewed-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>

Thanks.

> ---
> drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> index a07cf60..74613d3 100644
> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
> @@ -1135,7 +1135,7 @@ static void mvpp2_interrupts_mask(void *arg)
> struct mvpp2_port *port = arg;
>
> /* If the thread isn't used, don't do anything */
> - if (smp_processor_id() > port->priv->nthreads)
> + if (smp_processor_id() >= port->priv->nthreads)
> return;
>
> mvpp2_thread_write(port->priv,
> @@ -1153,7 +1153,7 @@ static void mvpp2_interrupts_unmask(void *arg)
> u32 val;
>
> /* If the thread isn't used, don't do anything */
> - if (smp_processor_id() > port->priv->nthreads)
> + if (smp_processor_id() >= port->priv->nthreads)
> return;
>
> val = MVPP2_CAUSE_MISC_SUM_MASK |
> --
> 1.9.1
>
>

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