diff mbox series

[v7,18/34] i2c: tegra: Remove likely/unlikely from the code

Message ID 20200908224006.25636-19-digetx@gmail.com
State Superseded
Headers show
Series Improvements for Tegra I2C driver | expand

Commit Message

Dmitry Osipenko Sept. 8, 2020, 10:39 p.m. UTC
The likely/unlikely annotations should be used only in a hot paths of
performance-critical code. The I2C driver doesn't have such paths, and
thus, there is no justification for usage of likely/unlikely annotations
in the code. Hence remove them.

Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 drivers/i2c/busses/i2c-tegra.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Thierry Reding Sept. 17, 2020, 12:41 p.m. UTC | #1
On Wed, Sep 09, 2020 at 01:39:50AM +0300, Dmitry Osipenko wrote:
> The likely/unlikely annotations should be used only in a hot paths of
> performance-critical code. The I2C driver doesn't have such paths, and
> thus, there is no justification for usage of likely/unlikely annotations
> in the code. Hence remove them.
> 
> Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
>  drivers/i2c/busses/i2c-tegra.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
> index ab83d1de6c94..fd0d51ec447f 100644
> --- a/drivers/i2c/busses/i2c-tegra.c
> +++ b/drivers/i2c/busses/i2c-tegra.c
> @@ -852,7 +852,7 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
>  		goto err;
>  	}
>  
> -	if (unlikely(status & status_err)) {
> +	if (status & status_err) {
>  		tegra_i2c_disable_packet_mode(i2c_dev);
>  		if (status & I2C_INT_NO_ACK)
>  			i2c_dev->msg_err |= I2C_ERR_NO_ACK;

At least this one is an interrupt handler, so it's kind of performance
critical. That said, it probably doesn't make a huge difference, so I
don't have any objection:

Acked-by: Thierry Reding <treding@nvidia.com>
Thierry Reding Sept. 21, 2020, 10:19 a.m. UTC | #2
On Wed, 09 Sep 2020 01:39:50 +0300, Dmitry Osipenko wrote:
> The likely/unlikely annotations should be used only in a hot paths of
> performance-critical code. The I2C driver doesn't have such paths, and
> thus, there is no justification for usage of likely/unlikely annotations
> in the code. Hence remove them.
> 
> Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> Acked-by: Thierry Reding <treding@nvidia.com>
> ---
>  drivers/i2c/busses/i2c-tegra.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Tested-by: Thierry Reding <treding@nvidia.com>
diff mbox series

Patch

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index ab83d1de6c94..fd0d51ec447f 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -852,7 +852,7 @@  static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
 		goto err;
 	}
 
-	if (unlikely(status & status_err)) {
+	if (status & status_err) {
 		tegra_i2c_disable_packet_mode(i2c_dev);
 		if (status & I2C_INT_NO_ACK)
 			i2c_dev->msg_err |= I2C_ERR_NO_ACK;
@@ -1294,7 +1294,7 @@  static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
 		i2c_dev->msg_err);
 
 	i2c_dev->is_curr_dma_xfer = false;
-	if (likely(i2c_dev->msg_err == I2C_ERR_NONE))
+	if (i2c_dev->msg_err == I2C_ERR_NONE)
 		return 0;
 
 	tegra_i2c_init(i2c_dev);