Hi Joe,
On 11/27/18 20:35, Joe Perches wrote:
On Tue, 2018-11-27 at 20:03 +0200, Georgi Djakov wrote:
This patch introduces a new API to get requirements and configure the
interconnect buses across the entire chipset to fit with the current
demand.
trivial notes:
diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c
[]
+static int apply_constraints(struct icc_path *path)
+{
+ struct icc_node *next, *prev = NULL;
+ int ret = -EINVAL;
+ int i;
+
+ for (i = 0; i < path->num_nodes; i++, prev = next) {
+ struct icc_provider *p;
+
+ next = path->reqs[i].node;
+ /*
+ * Both endpoints should be valid master-slave pairs of the
+ * same interconnect provider that will be configured.
+ */
+ if (!prev || next->provider != prev->provider)
+ continue;
+
+ p = next->provider;
+
+ /* set the constraints */
+ ret = p->set(prev, next);
+ if (ret)
+ goto out;
+ }
+out:
+ return ret;
+}
The use of ", prev = next" appears somewhat tricky code.
Perhaps move the assignment of prev to the bottom of the loop.
Perhaps the temporary p assignment isn't useful either.
+int icc_set(struct icc_path *path, u32 avg_bw, u32 peak_bw)
+{
[]
+ ret = apply_constraints(path);
+ if (ret)
+ pr_debug("interconnect: error applying constraints (%d)", ret);
Ideally all pr_<foo> formats should end in '\n'
+static struct icc_node *icc_node_create_nolock(int id)
+{
+ struct icc_node *node;
+
+ /* check if node already exists */
+ node = node_find(id);
+ if (node)
+ goto out;
+
+ node = kzalloc(sizeof(*node), GFP_KERNEL);
+ if (!node) {
+ node = ERR_PTR(-ENOMEM);
+ goto out;
Generally, this code appears to overly rely on goto when
direct returns could be more readable.
+ }
+
+ id = idr_alloc(&icc_idr, node, id, id + 1, GFP_KERNEL);
+ if (WARN(id < 0, "couldn't get idr")) {
This seems to unnecessarily hide the id < 0 test in a WARN
Why is this a WARN and not a simpler
if (id < 0) {
[ pr_err(...); or WARN(1, ...); ]
+ kfree(node);
+ node = ERR_PTR(id);
+ goto out;
+ }
+
+ node->id = id;
+
+out:
+ return node;
+}
Thank you for helping to improve the code. The above suggestions make it
cleaner indeed.
[]
diff --git a/include/linux/interconnect.h b/include/linux/interconnect.h
[]
+/* macros for converting to icc units */
+#define bps_to_icc(x) (1)
+#define kBps_to_icc(x) (x)
[]
+#define MBps_to_icc(x) (x * 1000)
+#define GBps_to_icc(x) (x * 1000 * 1000)
+#define kbps_to_icc(x) (x / 8 + ((x) % 8 ? 1 : 0))
+#define Mbps_to_icc(x) (x * 1000 / 8 )
+#define Gbps_to_icc(x) (x * 1000 * 1000 / 8)
The last 5 macros should parenthesize x
Oops.. obviously i forgot to run checkpatch --strict. Will fix!
BR,
Georgi
