Subject: Re: [PATCH] powerpc/pseries: fix max polling time in plpks_confirm_object_flushed() function

From: Michael Ellerman <[email-masked]>
Date: Tue, 05 Mar 2024 11:21:08 +1100

Nayna Jain <[email-masked]> writes:
> usleep_range() function takes input time and range in usec. However,
> currently it is assumed in msec in the function
> plpks_confirm_object_flushed().
>
> Fix the total polling time for the object flushing from 5msec to 5sec.
>
> Reported-by: Nageswara R Sastry <[email-masked]>
> Fixes: 2454a7af0f2a ("powerpc/pseries: define driver for Platform KeyStore")
> Signed-off-by: Nayna Jain <[email-masked]>
> Tested-by: Nageswara R Sastry <[email-masked]>
> ---
>  arch/powerpc/include/asm/plpks.h | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/plpks.h b/arch/powerpc/include/asm/plpks.h
> index 23b77027c916..8721d97f32c1 100644
> --- a/arch/powerpc/include/asm/plpks.h
> +++ b/arch/powerpc/include/asm/plpks.h
> @@ -44,9 +44,9 @@
>  #define PLPKS_MAX_DATA_SIZE		4000
>  
>  // Timeouts for PLPKS operations
> -#define PLPKS_MAX_TIMEOUT		5000 // msec
> -#define PLPKS_FLUSH_SLEEP		10 // msec
> -#define PLPKS_FLUSH_SLEEP_RANGE		400
> +#define PLPKS_MAX_TIMEOUT		5000000 // usec
> +#define PLPKS_FLUSH_SLEEP		5000 // usec
> +#define PLPKS_FLUSH_SLEEP_RANGE		5000

It would be simpler if you used fsleep, eg:

diff --git a/arch/powerpc/include/asm/plpks.h b/arch/powerpc/include/asm/plpks.h
index 23b77027c916..b2d419eff9cd 100644
--- a/arch/powerpc/include/asm/plpks.h
+++ b/arch/powerpc/include/asm/plpks.h
@@ -44,9 +44,8 @@
 #define PLPKS_MAX_DATA_SIZE		4000
 
 // Timeouts for PLPKS operations
-#define PLPKS_MAX_TIMEOUT		5000 // msec
-#define PLPKS_FLUSH_SLEEP		10 // msec
-#define PLPKS_FLUSH_SLEEP_RANGE		400
+#define PLPKS_MAX_TIMEOUT		5 * USEC_PER_SEC
+#define PLPKS_FLUSH_SLEEP		10000 // usec
 
 struct plpks_var {
 	char *component;
diff --git a/arch/powerpc/platforms/pseries/plpks.c b/arch/powerpc/platforms/pseries/plpks.c
index febe18f251d0..bcfcd5acc5c2 100644
--- a/arch/powerpc/platforms/pseries/plpks.c
+++ b/arch/powerpc/platforms/pseries/plpks.c
@@ -415,8 +415,7 @@ static int plpks_confirm_object_flushed(struct label *label,
 			break;
 		}
 
-		usleep_range(PLPKS_FLUSH_SLEEP,
-			     PLPKS_FLUSH_SLEEP + PLPKS_FLUSH_SLEEP_RANGE);
+		fsleep(PLPKS_FLUSH_SLEEP);
 		timeout = timeout + PLPKS_FLUSH_SLEEP;
 	} while (timeout < PLPKS_MAX_TIMEOUT);

cheers