From: Krzysztof Wilczyński <redacted>
Date: Wed, 24 Mar 2021 02:31:42 +0100

Hi Alexander,

Hi!

Thank you for sending the patch over!

quoted

A single dw_pcie entity can't be a root complex and an endpoint at
the same time.

Nice catch!

A small nitpick: this would be Root Complex and Endpoint, as it's
customary to capitalise these.

Also, if you could capitalise the subject line - it could also perhaps
be simplified to something like, for example:

  Optimize struct dw_pcie to reduce its size

Feel free to ignore both suggestions, as these are just nitpicks.

They are both correct, so I can send a v2 if this one wont't be
picked to the tree, let's say, this week.

quoted

We can use this to reduce the size of dw_pcie by 80, from 280 to 200
bytes (on x32, guess more on x64), by putting the related embedded
structures (struct pcie_port and struct dw_pcie_ep) into a union.

[...]

quoted

-	struct pcie_port	pp;
-	struct dw_pcie_ep	ep;
+	union {
+		struct pcie_port	pp;
+		struct dw_pcie_ep	ep;
+	};

[...]

How did you measure the difference?  Often, people include pahole output
for the "before" and "after", so to speak, to showcase the difference
and/or improvement.  Do you have something like that handy?

I didn't use pahole to measure the difference, just printed sizeofs
for the structures "before" and "after". But I can get pahole's
output and include it in v2 to make commit message more useful.

Krzysztof

Thanks!
Al