On Wed, May 09 2018 at 16:03 -0600, Matthias Kaehlcke wrote:
On Wed, May 09, 2018 at 11:01:58AM -0600, Lina Iyer wrote:Platform drivers need make a lot of resource state requests at the same time, say, at the start or end of an usecase. It can be quite inefficient to send each request separately. Instead they can give the RPMH library a batch of requests to be sent and wait on the whole transaction to be complete. rpmh_write_batch() is a blocking call that can be used to send multiple RPMH command sets. Each RPMH command set is set asynchronously and the API blocks until all the command sets are complete and receive their tx_done callbacks. Signed-off-by: Lina Iyer <ilina@xxxxxxxxxxxxxx> --- Changes in v7: - Check for loop out of bounds Changes in v6: - replace rpmh_client with device * Changes in v4: - reorganize rpmh_write_batch() - introduce wait_count here, instead of patch#4 --- drivers/soc/qcom/rpmh.c | 154 +++++++++++++++++++++++++++++++++++++++- include/soc/qcom/rpmh.h | 8 +++ 2 files changed, 160 insertions(+), 2 deletions(-) diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c index 1bb62876795c..a0e277b4b846 100644 --- a/drivers/soc/qcom/rpmh.c +++ b/drivers/soc/qcom/rpmh.c ... +static int flush_batch(struct rpmh_ctrlr *ctrlr) +{ + const struct rpmh_request *rpm_msg; + unsigned long flags; + int ret = 0; + int i; + + /* Send Sleep/Wake requests to the controller, expect no response */ + spin_lock_irqsave(&ctrlr->lock, flags); + for (i = 0; ctrlr->batch_cache[i]; i++) {I missed this earlier: the loop goes beyond ctrlr->batch_cache when the batch cache is full.+ rpm_msg = ctrlr->batch_cache[i]; + ret = rpmh_rsc_write_ctrl_data(ctrlr->drv, &rpm_msg->msg); + if (ret) + break; + } + spin_unlock_irqrestore(&ctrlr->lock, flags); + + return ret; +} + +static void invalidate_batch(struct rpmh_ctrlr *ctrlr) +{ + unsigned long flags; + int index = 0; + + spin_lock_irqsave(&ctrlr->lock, flags); + while (ctrlr->batch_cache[index]) {This still goes beyond ctrlr->batch_cache when the batch cache is full.
I will check through the code for all out-of-bounds. Seems like I have not worried about it too much. Well the space here assigned is beyond what we see on a production device. Neverthless, it needs to be checked. Thanks for your review Matthias. -- Lina -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
