diff mbox series

[v5,1/4] cxl: Remove checking of iter in cxl_endpoint_get_perf_coordinates()

Message ID 20240325230234.1847525-2-dave.jiang@intel.com
State Superseded
Headers show
Series cxl: access_coordinate validity fixes for 6.9 | expand

Commit Message

Dave Jiang March 25, 2024, 11 p.m. UTC 
The while() loop in cxl_endpoint_get_perf_coordinates() checks to see if
'iter' is valid as part of the condition breaking out of the loop. However,
iter is being used before the check at the end of the while loop before
the next iteration starts. Given that the loop doesn't expect the iter to
be NULL because it stops before the root port, remove the iter check.

The presence of the iter or removing the iter does not impact the behavior
of the code. This is a code clean up and not a bug fix.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
 drivers/cxl/core/port.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Dan Williams March 29, 2024, 1:26 a.m. UTC | #1 
Dave Jiang wrote:
> The while() loop in cxl_endpoint_get_perf_coordinates() checks to see if
> 'iter' is valid as part of the condition breaking out of the loop. However,
> iter is being used before the check at the end of the while loop before
> the next iteration starts. Given that the loop doesn't expect the iter to
> be NULL because it stops before the root port, remove the iter check.

This description can get much smaller by realizing that is_cxl_root()
will always stop the loop before the next iteration could go NULL. I.e.

> 
> The presence of the iter or removing the iter does not impact the behavior
> of the code. This is a code clean up and not a bug fix.
> 
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>

Even though the changelog is not as concise as it could be, you can add:

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
diff mbox series

Patch

diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index 2b0cab556072..6cbde50a742b 100644
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -2197,7 +2197,7 @@  int cxl_endpoint_get_perf_coordinates(struct cxl_port *port,
 	 * port each iteration. If the parent is cxl root then there is
 	 * nothing to gather.
 	 */
-	while (iter && !is_cxl_root(to_cxl_port(iter->dev.parent))) {
+	while (!is_cxl_root(to_cxl_port(iter->dev.parent))) {
 		cxl_coordinates_combine(&c, &c, &dport->sw_coord);
 		c.write_latency += dport->link_latency;
 		c.read_latency += dport->link_latency;