From 2e23fe68b72638a1185f6243528f05f7dc665a3a Mon Sep 17 00:00:00 2001 From: Nayna Jain Date: Tue, 14 Nov 2017 11:01:56 -0500 Subject: [PATCH] tpm: define __wait_for_tpm_stat to specify variable polling sleep time The existing wait_for_tpm_stat() checks the chip status before sleeping for 5 msec in a polling loop. For some functions although the status isn't ready immediately, the status returns extremely quickly. Waiting for 5 msec causes an unnecessary delay. An example is the send() call in the tpms_tis driver. This patch defines __wait_for_tpm_stat(), allowing the caller to specify the polling sleep timeout value within the loop. The existing wait_for_tpm_stat() becomes a wrapper for this function. After this change, performance on a TPM 1.2 with an 8 byte burstcount for 1000 extends improved from ~14sec to ~10sec. Signed-off-by: Nayna Jain Acked-by: Mimi Zohar --- tpm-interface.c | 15 ++++++++++++--- tpm.h | 3 +++ tpm_tis_core.c | 13 +++++++------ 3 files changed, 22 insertions(+), 9 deletions(-) diff --git a/tpm-interface.c b/tpm-interface.c index 9971422..69041ec 100644 --- a/tpm-interface.c +++ b/tpm-interface.c @@ -1015,8 +1015,9 @@ static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, return false; } -int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, - wait_queue_head_t *queue, bool check_cancel) +int __wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, + unsigned int poll_sleep, wait_queue_head_t *queue, + bool check_cancel) { unsigned long stop; long rc; @@ -1050,7 +1051,7 @@ again: } } else { do { - tpm_msleep(1); + tpm_msleep(poll_sleep); status = chip->ops->status(chip); if ((status & mask) == mask) return 0; @@ -1058,6 +1059,14 @@ again: } return -ETIME; } +EXPORT_SYMBOL_GPL(__wait_for_tpm_stat); + +int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, + wait_queue_head_t *queue, bool check_cancel) +{ + return __wait_for_tpm_stat(chip, mask, timeout, TPM_TIMEOUT, + queue, check_cancel); +} EXPORT_SYMBOL_GPL(wait_for_tpm_stat); #define TPM_ORD_SAVESTATE cpu_to_be32(152) diff --git a/tpm.h b/tpm.h index 6f3297e..e2c9f06 100644 --- a/tpm.h +++ b/tpm.h @@ -545,6 +545,9 @@ int tpm_do_selftest(struct tpm_chip *chip); unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal); int tpm_pm_suspend(struct device *dev); int tpm_pm_resume(struct device *dev); +int __wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, + unsigned long timeout, unsigned int poll_sleep, + wait_queue_head_t *queue, bool check_cancel); int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, wait_queue_head_t *queue, bool check_cancel); diff --git a/tpm_tis_core.c b/tpm_tis_core.c index d87255f..330b1a7 100644 --- a/tpm_tis_core.c +++ b/tpm_tis_core.c @@ -262,9 +262,9 @@ static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len) status = tpm_tis_status(chip); if ((status & TPM_STS_COMMAND_READY) == 0) { tpm_tis_ready(chip); - if (wait_for_tpm_stat - (chip, TPM_STS_COMMAND_READY, chip->timeout_b, - &priv->int_queue, false) < 0) { + if (__wait_for_tpm_stat + (chip, TPM_STS_COMMAND_READY, chip->timeout_b, 1, + &priv->int_queue, false) < 0) { rc = -ETIME; goto out_err; } @@ -285,7 +285,8 @@ static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len) count += burstcnt; - if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, + if (__wait_for_tpm_stat(chip, TPM_STS_VALID, + chip->timeout_c, 1, &priv->int_queue, false) < 0) { rc = -ETIME; goto out_err; @@ -302,8 +303,8 @@ static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len) if (rc < 0) goto out_err; - if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, - &priv->int_queue, false) < 0) { + if (__wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, + 1, &priv->int_queue, false) < 0) { rc = -ETIME; goto out_err; } -- 1.8.3.1