Quoting Stephen Boyd (2014-06-30 18:07:49)

On 06/30/14 17:52, Steven Rostedt wrote:

quoted

On Mon, 30 Jun 2014 16:56:39 -0700
Stephen Boyd [off-list ref] wrote:

quoted

@@ -483,10 +486,12 @@ static void clk_unprepare_unused_subtree(struct clk *clk)
             return;
 
     if (__clk_is_prepared(clk)) {
+            trace_clk_unprepare(clk);

Does it make sense to do these when clk->ops->unprepared_unused or
uprepare is not set?

You can use DEFINE_EVENT_CONDITIONAL() and add as condition:

   clk->ops->unprepared_unused || clk->ops->unprepare

Neat. I don't know if we actually want to do that though. If we always
record an event even when the hardware doesn't support the operation we
get information about events happening to the clock from a software
perspective. If that isn't important, then we can probably just put it
under the if conditions.

+1 for recording the tree walk even if no hardware operation is backing
it.

Regards,
Mike

quoted

quoted

             if (clk->ops->enable) {
                     ret = clk->ops->enable(clk->hw);
                     if (ret) {

@@ -945,6 +965,7 @@ static int __clk_enable(struct clk *clk)
                             return ret;

It may make even more sense to add the tracepoints within the if
statement. Especially if you have a return on error.

Right. I was thinking that no "clk*_complete" event would mean there was
some error. Detecting that case is not so easy though. It may be better
to always have the completion event so we know how long hardware
operations take and so that error handling is simpler.

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