diff mbox

[v2,4/4] tpm: use tpm_msleep() value as max delay

Message ID 20170906125643.5070-5-nayna@linux.vnet.ibm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Nayna Sept. 6, 2017, 12:56 p.m. UTC
Currently, tpm_msleep() uses delay_msec as the minimum value in
usleep_range. However, that is the maximum time we want to wait.
The function is modified to use the delay_msec as the maximum
value, not the minimum value.

After this change, performance on a TPM 1.2 with an 8 byte
burstcount for 1000 extends improved from ~9sec to ~8sec.

Signed-off-by: Nayna Jain <nayna@linux.vnet.ibm.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
---
 drivers/char/tpm/tpm.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Jarkko Sakkinen Sept. 13, 2017, 12:47 a.m. UTC | #1
On Wed, Sep 06, 2017 at 08:56:39AM -0400, Nayna Jain wrote:
> Currently, tpm_msleep() uses delay_msec as the minimum value in
> usleep_range. However, that is the maximum time we want to wait.
> The function is modified to use the delay_msec as the maximum
> value, not the minimum value.
> 
> After this change, performance on a TPM 1.2 with an 8 byte
> burstcount for 1000 extends improved from ~9sec to ~8sec.
> 
> Signed-off-by: Nayna Jain <nayna@linux.vnet.ibm.com>
> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
> ---
>  drivers/char/tpm/tpm.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> index eb2f8818eded..ff5a8b7b80b9 100644
> --- a/drivers/char/tpm/tpm.h
> +++ b/drivers/char/tpm/tpm.h
> @@ -533,8 +533,8 @@ int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
>  
>  static inline void tpm_msleep(unsigned int delay_msec)
>  {
> -	usleep_range(delay_msec * 1000,
> -		     (delay_msec * 1000) + TPM_TIMEOUT_RANGE_US);
> +	usleep_range((delay_msec * 1000) - TPM_TIMEOUT_RANGE_US,
> +		     delay_msec * 1000);
>  };
>  
>  struct tpm_chip *tpm_chip_find_get(int chip_num);
> -- 
> 2.13.3
> 

Doesn't this need a Fixes tag?

/Jarkko
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Nayna Sept. 14, 2017, 9:25 a.m. UTC | #2
On 09/13/2017 06:17 AM, Jarkko Sakkinen wrote:
> On Wed, Sep 06, 2017 at 08:56:39AM -0400, Nayna Jain wrote:
>> Currently, tpm_msleep() uses delay_msec as the minimum value in
>> usleep_range. However, that is the maximum time we want to wait.
>> The function is modified to use the delay_msec as the maximum
>> value, not the minimum value.
>>
>> After this change, performance on a TPM 1.2 with an 8 byte
>> burstcount for 1000 extends improved from ~9sec to ~8sec.
>>
>> Signed-off-by: Nayna Jain <nayna@linux.vnet.ibm.com>
>> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
>> ---
>>   drivers/char/tpm/tpm.h | 4 ++--
>>   1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
>> index eb2f8818eded..ff5a8b7b80b9 100644
>> --- a/drivers/char/tpm/tpm.h
>> +++ b/drivers/char/tpm/tpm.h
>> @@ -533,8 +533,8 @@ int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
>>   
>>   static inline void tpm_msleep(unsigned int delay_msec)
>>   {
>> -	usleep_range(delay_msec * 1000,
>> -		     (delay_msec * 1000) + TPM_TIMEOUT_RANGE_US);
>> +	usleep_range((delay_msec * 1000) - TPM_TIMEOUT_RANGE_US,
>> +		     delay_msec * 1000);
>>   };
>>   
>>   struct tpm_chip *tpm_chip_find_get(int chip_num);
>> -- 
>> 2.13.3
>>
> Doesn't this need a Fixes tag?
Yeah.. will add.

    - Nayna
> /Jarkko
>

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Jarkko Sakkinen Sept. 14, 2017, 12:28 p.m. UTC | #3
On Thu, Sep 14, 2017 at 02:55:34PM +0530, Nayna Jain wrote:
> 
> 
> On 09/13/2017 06:17 AM, Jarkko Sakkinen wrote:
> > On Wed, Sep 06, 2017 at 08:56:39AM -0400, Nayna Jain wrote:
> > > Currently, tpm_msleep() uses delay_msec as the minimum value in
> > > usleep_range. However, that is the maximum time we want to wait.
> > > The function is modified to use the delay_msec as the maximum
> > > value, not the minimum value.
> > > 
> > > After this change, performance on a TPM 1.2 with an 8 byte
> > > burstcount for 1000 extends improved from ~9sec to ~8sec.
> > > 
> > > Signed-off-by: Nayna Jain <nayna@linux.vnet.ibm.com>
> > > Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
> > > ---
> > >   drivers/char/tpm/tpm.h | 4 ++--
> > >   1 file changed, 2 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> > > index eb2f8818eded..ff5a8b7b80b9 100644
> > > --- a/drivers/char/tpm/tpm.h
> > > +++ b/drivers/char/tpm/tpm.h
> > > @@ -533,8 +533,8 @@ int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
> > >   static inline void tpm_msleep(unsigned int delay_msec)
> > >   {
> > > -	usleep_range(delay_msec * 1000,
> > > -		     (delay_msec * 1000) + TPM_TIMEOUT_RANGE_US);
> > > +	usleep_range((delay_msec * 1000) - TPM_TIMEOUT_RANGE_US,
> > > +		     delay_msec * 1000);
> > >   };
> > >   struct tpm_chip *tpm_chip_find_get(int chip_num);
> > > -- 
> > > 2.13.3
> > > 
> > Doesn't this need a Fixes tag?
> Yeah.. will add.

No need just for that. I'll test this when I'm back in Finland.
It was a question just to check that I'm in the same page  :-)

/Jarkko
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diff mbox

Patch

diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index eb2f8818eded..ff5a8b7b80b9 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -533,8 +533,8 @@  int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
 
 static inline void tpm_msleep(unsigned int delay_msec)
 {
-	usleep_range(delay_msec * 1000,
-		     (delay_msec * 1000) + TPM_TIMEOUT_RANGE_US);
+	usleep_range((delay_msec * 1000) - TPM_TIMEOUT_RANGE_US,
+		     delay_msec * 1000);
 };
 
 struct tpm_chip *tpm_chip_find_get(int chip_num);