Hi Mathieu,
On 14/05/2019 20:40, Mathieu Poirier wrote:
Unify amongst sink drivers how the AUX ring buffer head is communicated to user space. That way the same algorithm in cs_etm_find_snapshot()
I would leave the userspace tool's function name out of the commit description and the comment below. We could instead say: "That way the same algorithm can be used by the userspace tool to determine the position and the size of the latest snapshot data."
can be used to determine where the latest data is and how much of it to access.
Signed-off-by: Mathieu Poirier mathieu.poirier@linaro.org
drivers/hwtracing/coresight/coresight-etb10.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c index 4ee4c80a4354..60e753b1768d 100644 --- a/drivers/hwtracing/coresight/coresight-etb10.c +++ b/drivers/hwtracing/coresight/coresight-etb10.c @@ -548,13 +548,14 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev, writel_relaxed(0x0, drvdata->base + ETB_RAM_WRITE_POINTER); /*
* In snapshot mode we have to update the handle->head to point* to the new location.
* In snapshot mode we simply increment the head by the number of byte* that were written. User space function cs_etm_find_snapshot() will* figure out how many bytes to get from the AUX buffer based on the* position of the head.
- if (buf->snapshot) {
handle->head = (cur * PAGE_SIZE) + offset;to_read = buf->nr_pages << PAGE_SHIFT;- }
- if (buf->snapshot)
handle->head += to_read;- __etb_enable_hw(drvdata); CS_LOCK(drvdata->base); out:
Otherwise:
Reviewed-by: Suzuki K Poulose suzuki.poulose@arm.com