* [PATCH] counter: ti-eqep: Use container_of instead of struct counter_device::priv
@ 2021-12-13 11:43 Uwe Kleine-König
2021-12-13 15:50 ` David Lechner
2021-12-16 5:25 ` William Breathitt Gray
0 siblings, 2 replies; 5+ messages in thread
From: Uwe Kleine-König @ 2021-12-13 11:43 UTC (permalink / raw)
To: William Breathitt Gray; +Cc: David Lechner, linux-iio, kernel
Using counter->priv is a memory read and so more expensive than
container_of which is only an addition. (In this case even a noop
because the offset is 0.)
So container_of is expected to be a tad faster, it's type-safe, and
produces smaller code (ARCH=arm allmodconfig):
$ source/scripts/bloat-o-meter drivers/counter/ti-eqep.o-pre drivers/counter/ti-eqep.o
add/remove: 0/0 grow/shrink: 0/9 up/down: 0/-108 (-108)
Function old new delta
ti_eqep_position_enable_write 132 120 -12
ti_eqep_position_enable_read 260 248 -12
ti_eqep_position_ceiling_write 132 120 -12
ti_eqep_position_ceiling_read 236 224 -12
ti_eqep_function_write 220 208 -12
ti_eqep_function_read 372 360 -12
ti_eqep_count_write 312 300 -12
ti_eqep_count_read 236 224 -12
ti_eqep_action_read 664 652 -12
Total: Before=4598, After=4490, chg -2.35%
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
drivers/counter/ti-eqep.c | 23 ++++++++++++++---------
1 file changed, 14 insertions(+), 9 deletions(-)
diff --git a/drivers/counter/ti-eqep.c b/drivers/counter/ti-eqep.c
index 09817c953f9a..9e0e46bca4c2 100644
--- a/drivers/counter/ti-eqep.c
+++ b/drivers/counter/ti-eqep.c
@@ -87,10 +87,15 @@ struct ti_eqep_cnt {
struct regmap *regmap16;
};
+static struct ti_eqep_cnt *ti_eqep_count_from_counter(struct counter_device *counter)
+{
+ return container_of(counter, struct ti_eqep_cnt, counter);
+}
+
static int ti_eqep_count_read(struct counter_device *counter,
struct counter_count *count, u64 *val)
{
- struct ti_eqep_cnt *priv = counter->priv;
+ struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
u32 cnt;
regmap_read(priv->regmap32, QPOSCNT, &cnt);
@@ -102,7 +107,7 @@ static int ti_eqep_count_read(struct counter_device *counter,
static int ti_eqep_count_write(struct counter_device *counter,
struct counter_count *count, u64 val)
{
- struct ti_eqep_cnt *priv = counter->priv;
+ struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
u32 max;
regmap_read(priv->regmap32, QPOSMAX, &max);
@@ -116,7 +121,7 @@ static int ti_eqep_function_read(struct counter_device *counter,
struct counter_count *count,
enum counter_function *function)
{
- struct ti_eqep_cnt *priv = counter->priv;
+ struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
u32 qdecctl;
regmap_read(priv->regmap16, QDECCTL, &qdecctl);
@@ -143,7 +148,7 @@ static int ti_eqep_function_write(struct counter_device *counter,
struct counter_count *count,
enum counter_function function)
{
- struct ti_eqep_cnt *priv = counter->priv;
+ struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
enum ti_eqep_count_func qsrc;
switch (function) {
@@ -173,7 +178,7 @@ static int ti_eqep_action_read(struct counter_device *counter,
struct counter_synapse *synapse,
enum counter_synapse_action *action)
{
- struct ti_eqep_cnt *priv = counter->priv;
+ struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
enum counter_function function;
u32 qdecctl;
int err;
@@ -245,7 +250,7 @@ static int ti_eqep_position_ceiling_read(struct counter_device *counter,
struct counter_count *count,
u64 *ceiling)
{
- struct ti_eqep_cnt *priv = counter->priv;
+ struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
u32 qposmax;
regmap_read(priv->regmap32, QPOSMAX, &qposmax);
@@ -259,7 +264,7 @@ static int ti_eqep_position_ceiling_write(struct counter_device *counter,
struct counter_count *count,
u64 ceiling)
{
- struct ti_eqep_cnt *priv = counter->priv;
+ struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
if (ceiling != (u32)ceiling)
return -ERANGE;
@@ -272,7 +277,7 @@ static int ti_eqep_position_ceiling_write(struct counter_device *counter,
static int ti_eqep_position_enable_read(struct counter_device *counter,
struct counter_count *count, u8 *enable)
{
- struct ti_eqep_cnt *priv = counter->priv;
+ struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
u32 qepctl;
regmap_read(priv->regmap16, QEPCTL, &qepctl);
@@ -285,7 +290,7 @@ static int ti_eqep_position_enable_read(struct counter_device *counter,
static int ti_eqep_position_enable_write(struct counter_device *counter,
struct counter_count *count, u8 enable)
{
- struct ti_eqep_cnt *priv = counter->priv;
+ struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
regmap_write_bits(priv->regmap16, QEPCTL, QEPCTL_PHEN, enable ? -1 : 0);
base-commit: fa55b7dcdc43c1aa1ba12bca9d2dd4318c2a0dbf
--
2.30.2
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH] counter: ti-eqep: Use container_of instead of struct counter_device::priv
2021-12-13 11:43 [PATCH] counter: ti-eqep: Use container_of instead of struct counter_device::priv Uwe Kleine-König
@ 2021-12-13 15:50 ` David Lechner
2021-12-16 5:25 ` William Breathitt Gray
1 sibling, 0 replies; 5+ messages in thread
From: David Lechner @ 2021-12-13 15:50 UTC (permalink / raw)
To: Uwe Kleine-König, William Breathitt Gray; +Cc: linux-iio, kernel
On 12/13/21 5:43 AM, Uwe Kleine-König wrote:
> Using counter->priv is a memory read and so more expensive than
> container_of which is only an addition. (In this case even a noop
> because the offset is 0.)
>
> So container_of is expected to be a tad faster, it's type-safe, and
> produces smaller code (ARCH=arm allmodconfig):
>
> $ source/scripts/bloat-o-meter drivers/counter/ti-eqep.o-pre drivers/counter/ti-eqep.o
> add/remove: 0/0 grow/shrink: 0/9 up/down: 0/-108 (-108)
> Function old new delta
> ti_eqep_position_enable_write 132 120 -12
> ti_eqep_position_enable_read 260 248 -12
> ti_eqep_position_ceiling_write 132 120 -12
> ti_eqep_position_ceiling_read 236 224 -12
> ti_eqep_function_write 220 208 -12
> ti_eqep_function_read 372 360 -12
> ti_eqep_count_write 312 300 -12
> ti_eqep_count_read 236 224 -12
> ti_eqep_action_read 664 652 -12
> Total: Before=4598, After=4490, chg -2.35%
>
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> ---
Acked-by: David Lechner <david@lechnology.com>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] counter: ti-eqep: Use container_of instead of struct counter_device::priv
2021-12-13 11:43 [PATCH] counter: ti-eqep: Use container_of instead of struct counter_device::priv Uwe Kleine-König
2021-12-13 15:50 ` David Lechner
@ 2021-12-16 5:25 ` William Breathitt Gray
2021-12-16 10:49 ` Uwe Kleine-König
1 sibling, 1 reply; 5+ messages in thread
From: William Breathitt Gray @ 2021-12-16 5:25 UTC (permalink / raw)
To: Uwe Kleine-König; +Cc: David Lechner, linux-iio, kernel
[-- Attachment #1: Type: text/plain, Size: 5447 bytes --]
On Mon, Dec 13, 2021 at 12:43:12PM +0100, Uwe Kleine-König wrote:
> Using counter->priv is a memory read and so more expensive than
> container_of which is only an addition. (In this case even a noop
> because the offset is 0.)
>
> So container_of is expected to be a tad faster, it's type-safe, and
> produces smaller code (ARCH=arm allmodconfig):
>
> $ source/scripts/bloat-o-meter drivers/counter/ti-eqep.o-pre drivers/counter/ti-eqep.o
> add/remove: 0/0 grow/shrink: 0/9 up/down: 0/-108 (-108)
> Function old new delta
> ti_eqep_position_enable_write 132 120 -12
> ti_eqep_position_enable_read 260 248 -12
> ti_eqep_position_ceiling_write 132 120 -12
> ti_eqep_position_ceiling_read 236 224 -12
> ti_eqep_function_write 220 208 -12
> ti_eqep_function_read 372 360 -12
> ti_eqep_count_write 312 300 -12
> ti_eqep_count_read 236 224 -12
> ti_eqep_action_read 664 652 -12
> Total: Before=4598, After=4490, chg -2.35%
>
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
I'll pick this up and submit it with the rest of the Counter changes for
this cycle.
Thanks,
William Breathitt Gray
> ---
> drivers/counter/ti-eqep.c | 23 ++++++++++++++---------
> 1 file changed, 14 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/counter/ti-eqep.c b/drivers/counter/ti-eqep.c
> index 09817c953f9a..9e0e46bca4c2 100644
> --- a/drivers/counter/ti-eqep.c
> +++ b/drivers/counter/ti-eqep.c
> @@ -87,10 +87,15 @@ struct ti_eqep_cnt {
> struct regmap *regmap16;
> };
>
> +static struct ti_eqep_cnt *ti_eqep_count_from_counter(struct counter_device *counter)
> +{
> + return container_of(counter, struct ti_eqep_cnt, counter);
> +}
> +
> static int ti_eqep_count_read(struct counter_device *counter,
> struct counter_count *count, u64 *val)
> {
> - struct ti_eqep_cnt *priv = counter->priv;
> + struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
> u32 cnt;
>
> regmap_read(priv->regmap32, QPOSCNT, &cnt);
> @@ -102,7 +107,7 @@ static int ti_eqep_count_read(struct counter_device *counter,
> static int ti_eqep_count_write(struct counter_device *counter,
> struct counter_count *count, u64 val)
> {
> - struct ti_eqep_cnt *priv = counter->priv;
> + struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
> u32 max;
>
> regmap_read(priv->regmap32, QPOSMAX, &max);
> @@ -116,7 +121,7 @@ static int ti_eqep_function_read(struct counter_device *counter,
> struct counter_count *count,
> enum counter_function *function)
> {
> - struct ti_eqep_cnt *priv = counter->priv;
> + struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
> u32 qdecctl;
>
> regmap_read(priv->regmap16, QDECCTL, &qdecctl);
> @@ -143,7 +148,7 @@ static int ti_eqep_function_write(struct counter_device *counter,
> struct counter_count *count,
> enum counter_function function)
> {
> - struct ti_eqep_cnt *priv = counter->priv;
> + struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
> enum ti_eqep_count_func qsrc;
>
> switch (function) {
> @@ -173,7 +178,7 @@ static int ti_eqep_action_read(struct counter_device *counter,
> struct counter_synapse *synapse,
> enum counter_synapse_action *action)
> {
> - struct ti_eqep_cnt *priv = counter->priv;
> + struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
> enum counter_function function;
> u32 qdecctl;
> int err;
> @@ -245,7 +250,7 @@ static int ti_eqep_position_ceiling_read(struct counter_device *counter,
> struct counter_count *count,
> u64 *ceiling)
> {
> - struct ti_eqep_cnt *priv = counter->priv;
> + struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
> u32 qposmax;
>
> regmap_read(priv->regmap32, QPOSMAX, &qposmax);
> @@ -259,7 +264,7 @@ static int ti_eqep_position_ceiling_write(struct counter_device *counter,
> struct counter_count *count,
> u64 ceiling)
> {
> - struct ti_eqep_cnt *priv = counter->priv;
> + struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
>
> if (ceiling != (u32)ceiling)
> return -ERANGE;
> @@ -272,7 +277,7 @@ static int ti_eqep_position_ceiling_write(struct counter_device *counter,
> static int ti_eqep_position_enable_read(struct counter_device *counter,
> struct counter_count *count, u8 *enable)
> {
> - struct ti_eqep_cnt *priv = counter->priv;
> + struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
> u32 qepctl;
>
> regmap_read(priv->regmap16, QEPCTL, &qepctl);
> @@ -285,7 +290,7 @@ static int ti_eqep_position_enable_read(struct counter_device *counter,
> static int ti_eqep_position_enable_write(struct counter_device *counter,
> struct counter_count *count, u8 enable)
> {
> - struct ti_eqep_cnt *priv = counter->priv;
> + struct ti_eqep_cnt *priv = ti_eqep_count_from_counter(counter);
>
> regmap_write_bits(priv->regmap16, QEPCTL, QEPCTL_PHEN, enable ? -1 : 0);
>
>
> base-commit: fa55b7dcdc43c1aa1ba12bca9d2dd4318c2a0dbf
> --
> 2.30.2
>
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^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] counter: ti-eqep: Use container_of instead of struct counter_device::priv
2021-12-16 5:25 ` William Breathitt Gray
@ 2021-12-16 10:49 ` Uwe Kleine-König
2021-12-16 23:31 ` William Breathitt Gray
0 siblings, 1 reply; 5+ messages in thread
From: Uwe Kleine-König @ 2021-12-16 10:49 UTC (permalink / raw)
To: William Breathitt Gray; +Cc: linux-iio, David Lechner, kernel
[-- Attachment #1: Type: text/plain, Size: 3165 bytes --]
hello William,
On Thu, Dec 16, 2021 at 02:25:03PM +0900, William Breathitt Gray wrote:
> On Mon, Dec 13, 2021 at 12:43:12PM +0100, Uwe Kleine-König wrote:
> > Using counter->priv is a memory read and so more expensive than
> > container_of which is only an addition. (In this case even a noop
> > because the offset is 0.)
> >
> > So container_of is expected to be a tad faster, it's type-safe, and
> > produces smaller code (ARCH=arm allmodconfig):
> >
> > $ source/scripts/bloat-o-meter drivers/counter/ti-eqep.o-pre drivers/counter/ti-eqep.o
> > add/remove: 0/0 grow/shrink: 0/9 up/down: 0/-108 (-108)
> > Function old new delta
> > ti_eqep_position_enable_write 132 120 -12
> > ti_eqep_position_enable_read 260 248 -12
> > ti_eqep_position_ceiling_write 132 120 -12
> > ti_eqep_position_ceiling_read 236 224 -12
> > ti_eqep_function_write 220 208 -12
> > ti_eqep_function_read 372 360 -12
> > ti_eqep_count_write 312 300 -12
> > ti_eqep_count_read 236 224 -12
> > ti_eqep_action_read 664 652 -12
> > Total: Before=4598, After=4490, chg -2.35%
> >
> > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
>
> I'll pick this up and submit it with the rest of the Counter changes for
> this cycle.
This is great. The same transformation could be done for the other
drivers using the priv pointer. Then priv could be removed from struct
counter_device. Good idea?
A quick prototype patch yields:
drivers/counter/104-quad-8.o
add/remove: 0/0 grow/shrink: 5/17 up/down: 76/-172 (-96)
Total: Before=11802, After=11706, chg -0.81%
drivers/counter/ftm-quaddec.o
add/remove: 0/0 grow/shrink: 0/5 up/down: 0/-60 (-60)
Total: Before=5096, After=5036, chg -1.18%
drivers/counter/intel-qep.o
add/remove: 0/0 grow/shrink: 0/10 up/down: 0/-116 (-116)
Total: Before=4867, After=4751, chg -2.38%
drivers/counter/interrupt-cnt.o
add/remove: 0/0 grow/shrink: 0/6 up/down: 0/-60 (-60)
Total: Before=2841, After=2781, chg -2.11%
drivers/counter/microchip-tcb-capture.o
add/remove: 0/0 grow/shrink: 1/6 up/down: 12/-68 (-56)
Total: Before=5920, After=5864, chg -0.95%
drivers/counter/stm32-lptimer-cnt.o
add/remove: 0/0 grow/shrink: 0/10 up/down: 0/-140 (-140)
Total: Before=6458, After=6318, chg -2.17%
drivers/counter/stm32-timer-cnt.o
add/remove: 0/0 grow/shrink: 0/11 up/down: 0/-132 (-132)
Total: Before=5504, After=5372, chg -2.40%
drivers/counter/ti-eqep.o
add/remove: 0/0 grow/shrink: 0/10 up/down: 0/-120 (-120)
Total: Before=4598, After=4478, chg -2.61%
(the ti-eqep object file got a bit smaller, probably because I removed
the priv member from struct counter_device.)
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | https://www.pengutronix.de/ |
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^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] counter: ti-eqep: Use container_of instead of struct counter_device::priv
2021-12-16 10:49 ` Uwe Kleine-König
@ 2021-12-16 23:31 ` William Breathitt Gray
0 siblings, 0 replies; 5+ messages in thread
From: William Breathitt Gray @ 2021-12-16 23:31 UTC (permalink / raw)
To: Uwe Kleine-König; +Cc: linux-iio, David Lechner, kernel
[-- Attachment #1: Type: text/plain, Size: 3557 bytes --]
On Thu, Dec 16, 2021 at 11:49:15AM +0100, Uwe Kleine-König wrote:
> hello William,
>
> On Thu, Dec 16, 2021 at 02:25:03PM +0900, William Breathitt Gray wrote:
> > On Mon, Dec 13, 2021 at 12:43:12PM +0100, Uwe Kleine-König wrote:
> > > Using counter->priv is a memory read and so more expensive than
> > > container_of which is only an addition. (In this case even a noop
> > > because the offset is 0.)
> > >
> > > So container_of is expected to be a tad faster, it's type-safe, and
> > > produces smaller code (ARCH=arm allmodconfig):
> > >
> > > $ source/scripts/bloat-o-meter drivers/counter/ti-eqep.o-pre drivers/counter/ti-eqep.o
> > > add/remove: 0/0 grow/shrink: 0/9 up/down: 0/-108 (-108)
> > > Function old new delta
> > > ti_eqep_position_enable_write 132 120 -12
> > > ti_eqep_position_enable_read 260 248 -12
> > > ti_eqep_position_ceiling_write 132 120 -12
> > > ti_eqep_position_ceiling_read 236 224 -12
> > > ti_eqep_function_write 220 208 -12
> > > ti_eqep_function_read 372 360 -12
> > > ti_eqep_count_write 312 300 -12
> > > ti_eqep_count_read 236 224 -12
> > > ti_eqep_action_read 664 652 -12
> > > Total: Before=4598, After=4490, chg -2.35%
> > >
> > > Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> >
> > I'll pick this up and submit it with the rest of the Counter changes for
> > this cycle.
>
> This is great. The same transformation could be done for the other
> drivers using the priv pointer. Then priv could be removed from struct
> counter_device. Good idea?
Sure, that sounds reasonable. Create a patchset with the changes, CC the
respective driver maintainers, and we'll see if we can merge those too.
William Breathitt Gray
>
> A quick prototype patch yields:
>
> drivers/counter/104-quad-8.o
> add/remove: 0/0 grow/shrink: 5/17 up/down: 76/-172 (-96)
> Total: Before=11802, After=11706, chg -0.81%
> drivers/counter/ftm-quaddec.o
> add/remove: 0/0 grow/shrink: 0/5 up/down: 0/-60 (-60)
> Total: Before=5096, After=5036, chg -1.18%
> drivers/counter/intel-qep.o
> add/remove: 0/0 grow/shrink: 0/10 up/down: 0/-116 (-116)
> Total: Before=4867, After=4751, chg -2.38%
> drivers/counter/interrupt-cnt.o
> add/remove: 0/0 grow/shrink: 0/6 up/down: 0/-60 (-60)
> Total: Before=2841, After=2781, chg -2.11%
> drivers/counter/microchip-tcb-capture.o
> add/remove: 0/0 grow/shrink: 1/6 up/down: 12/-68 (-56)
> Total: Before=5920, After=5864, chg -0.95%
> drivers/counter/stm32-lptimer-cnt.o
> add/remove: 0/0 grow/shrink: 0/10 up/down: 0/-140 (-140)
> Total: Before=6458, After=6318, chg -2.17%
> drivers/counter/stm32-timer-cnt.o
> add/remove: 0/0 grow/shrink: 0/11 up/down: 0/-132 (-132)
> Total: Before=5504, After=5372, chg -2.40%
> drivers/counter/ti-eqep.o
> add/remove: 0/0 grow/shrink: 0/10 up/down: 0/-120 (-120)
> Total: Before=4598, After=4478, chg -2.61%
>
> (the ti-eqep object file got a bit smaller, probably because I removed
> the priv member from struct counter_device.)
>
> Best regards
> Uwe
>
> --
> Pengutronix e.K. | Uwe Kleine-König |
> Industrial Linux Solutions | https://www.pengutronix.de/ |
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2021-12-13 11:43 [PATCH] counter: ti-eqep: Use container_of instead of struct counter_device::priv Uwe Kleine-König
2021-12-13 15:50 ` David Lechner
2021-12-16 5:25 ` William Breathitt Gray
2021-12-16 10:49 ` Uwe Kleine-König
2021-12-16 23:31 ` William Breathitt Gray
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