On 09/13/2017 06:17 AM, Jarkko Sakkinen wrote:

On Wed, Sep 06, 2017 at 08:56:39AM -0400, Nayna Jain wrote:

quoted

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 <redacted>
Acked-by: Mimi Zohar <redacted>
---
  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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