Re: [PATCH v2] coccicheck: process every source file at once
- Date: Tue, 2 Oct 2018 13:04:25 -0700
- From: Jacob Keller <jacob.keller@xxxxxxxxx>
- Subject: Re: [PATCH v2] coccicheck: process every source file at once
On Tue, Oct 2, 2018 at 1:03 PM Jacob Keller <jacob.e.keller@xxxxxxxxx> wrote:
> From: Jacob Keller <jacob.keller@xxxxxxxxx>
> make coccicheck is used in order to apply coccinelle semantic patches,
> and see if any of the transformations found within contrib/coccinelle/
> can be applied to the current code base.
> Pass every file to a single invocation of spatch, instead of running
> spatch once per source file.
> This reduces the time required to run make coccicheck by a significant
> amount of time:
> Prior timing of make coccicheck
> real 6m14.090s
> user 25m2.606s
> sys 1m22.919s
> New timing of make coccicheck
> real 1m36.580s
> user 7m55.933s
> sys 0m18.219s
> This is nearly a 4x decrease in the time required to run make
> coccicheck. This is due to the overhead of restarting spatch for every
> file. By processing all files at once, we can amortize this startup cost
> across the total number of files, rather than paying it once per file.
> Signed-off-by: Jacob Keller <jacob.keller@xxxxxxxxx>
Woops, ignore this version, it doesn't quite work.