diff mbox series

drivers/cros_ec: Make log polling period a parameter

Message ID 20240507155809.525701-1-robbarnes@google.com (mailing list archive)
State Accepted
Commit 7b44d5381e541de3da3cee2e948456b250f41f25
Headers show
Series drivers/cros_ec: Make log polling period a parameter | expand

Commit Message

Rob Barnes May 7, 2024, 3:58 p.m. UTC
Make EC log polling period a module parameter. This allows the polling
period to be set via the kernel command line. Keeping the default at
the current 10 second period. The optimal polling period will differ by
board.

Signed-off-by: Rob Barnes <robbarnes@google.com>
---
 drivers/platform/chrome/cros_ec_debugfs.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

Comments

Tzung-Bi Shih May 23, 2024, 1:30 a.m. UTC | #1
On Tue, May 07, 2024 at 03:58:09PM +0000, Rob Barnes wrote:
> Make EC log polling period a module parameter. This allows the polling
> period to be set via the kernel command line. Keeping the default at
> the current 10 second period. The optimal polling period will differ by
> board.

If you get chance for sending next version, please use title prefix
"platform/chrome: cros_ec_debugfs:".

> @@ -118,7 +122,7 @@ static void cros_ec_console_log_work(struct work_struct *__work)
>  
>  resched:
>  	schedule_delayed_work(&debug_info->log_poll_work,
> -			      msecs_to_jiffies(LOG_POLL_SEC * 1000));
> +			      msecs_to_jiffies(log_poll_period_ms));

If the value is set to 0, it works like an infinite loop on
cros_ec_console_log_work().  Is it expected?
Rob Barnes May 29, 2024, 12:08 a.m. UTC | #2
On Wed, May 22, 2024 at 7:30 PM Tzung-Bi Shih <tzungbi@kernel.org> wrote:
>
> On Tue, May 07, 2024 at 03:58:09PM +0000, Rob Barnes wrote:
> > Make EC log polling period a module parameter. This allows the polling
> > period to be set via the kernel command line. Keeping the default at
> > the current 10 second period. The optimal polling period will differ by
> > board.
>
> If you get chance for sending next version, please use title prefix
> "platform/chrome: cros_ec_debugfs:".
>
> > @@ -118,7 +122,7 @@ static void cros_ec_console_log_work(struct work_struct *__work)
> >
> >  resched:
> >       schedule_delayed_work(&debug_info->log_poll_work,
> > -                           msecs_to_jiffies(LOG_POLL_SEC * 1000));
> > +                           msecs_to_jiffies(log_poll_period_ms));
>
> If the value is set to 0, it works like an infinite loop on
> cros_ec_console_log_work().  Is it expected?

Yes. I think this result is clear from the parameter name,
"log_poll_period_ms", i.e. a developer setting this parameter to 0
would expect the EC log to be polled as fast as possible. This may be
done for testing, but it wouldn't make sense in production. We could
enforce an absolute minimum, but the value would be mostly a guess.
Let me know if you still want a minimum enforced and if you have a
recommendation on the value?
patchwork-bot+chrome-platform@kernel.org May 29, 2024, 5:20 a.m. UTC | #3
Hello:

This patch was applied to chrome-platform/linux.git (for-kernelci)
by Tzung-Bi Shih <tzungbi@kernel.org>:

On Tue,  7 May 2024 15:58:09 +0000 you wrote:
> Make EC log polling period a module parameter. This allows the polling
> period to be set via the kernel command line. Keeping the default at
> the current 10 second period. The optimal polling period will differ by
> board.
> 
> Signed-off-by: Rob Barnes <robbarnes@google.com>
> 
> [...]

Here is the summary with links:
  - drivers/cros_ec: Make log polling period a parameter
    https://git.kernel.org/chrome-platform/c/7b44d5381e54

You are awesome, thank you!
patchwork-bot+chrome-platform@kernel.org May 29, 2024, 5:20 a.m. UTC | #4
Hello:

This patch was applied to chrome-platform/linux.git (for-next)
by Tzung-Bi Shih <tzungbi@kernel.org>:

On Tue,  7 May 2024 15:58:09 +0000 you wrote:
> Make EC log polling period a module parameter. This allows the polling
> period to be set via the kernel command line. Keeping the default at
> the current 10 second period. The optimal polling period will differ by
> board.
> 
> Signed-off-by: Rob Barnes <robbarnes@google.com>
> 
> [...]

Here is the summary with links:
  - drivers/cros_ec: Make log polling period a parameter
    https://git.kernel.org/chrome-platform/c/7b44d5381e54

You are awesome, thank you!
diff mbox series

Patch

diff --git a/drivers/platform/chrome/cros_ec_debugfs.c b/drivers/platform/chrome/cros_ec_debugfs.c
index 6bf6f0e7b597..95101b0d5227 100644
--- a/drivers/platform/chrome/cros_ec_debugfs.c
+++ b/drivers/platform/chrome/cros_ec_debugfs.c
@@ -25,6 +25,10 @@ 
 
 #define CIRC_ADD(idx, size, value)	(((idx) + (value)) & ((size) - 1))
 
+static unsigned int log_poll_period_ms = LOG_POLL_SEC * MSEC_PER_SEC;
+module_param(log_poll_period_ms, uint, 0644);
+MODULE_PARM_DESC(log_poll_period_ms, "EC log polling period(ms)");
+
 /* waitqueue for log readers */
 static DECLARE_WAIT_QUEUE_HEAD(cros_ec_debugfs_log_wq);
 
@@ -56,7 +60,7 @@  struct cros_ec_debugfs {
 
 /*
  * We need to make sure that the EC log buffer on the UART is large enough,
- * so that it is unlikely enough to overlow within LOG_POLL_SEC.
+ * so that it is unlikely enough to overlow within log_poll_period_ms.
  */
 static void cros_ec_console_log_work(struct work_struct *__work)
 {
@@ -118,7 +122,7 @@  static void cros_ec_console_log_work(struct work_struct *__work)
 
 resched:
 	schedule_delayed_work(&debug_info->log_poll_work,
-			      msecs_to_jiffies(LOG_POLL_SEC * 1000));
+			      msecs_to_jiffies(log_poll_period_ms));
 }
 
 static int cros_ec_console_log_open(struct inode *inode, struct file *file)