On Sun, 25 Oct 2020, Markus Elfring wrote: > From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx> > Date: Sun, 25 Oct 2020 18:54:36 +0100 > > A disjunction is applied by this script for the semantic patch language. > This construct uses short-circuit evaluation. It has got the consequence > that the last element of the specified condition will only be checked > if all previous parts did not match. Such a technical detail leads to > a recommended ordering of condition parts if you would like to care for > optimal run time characteristics of SmPL code. > > An usage incidence was determined for the specified identifiers in source > files from the software “Linux next-20201023” by another SmPL script. > > See also: > Determination of an usage statistic for memory allocation calls > https://lore.kernel.org/cocci/2774601.u91sIFNy1E@sonne/ > > This analysis result indicates a clear ranking for such function calls. > Thus reorder the SmPL disjunction items according to their usage incidence. Did you actually test this before and after the change and see a difference in performance? On my laptop, I see absolutely no difference, for the patch mode and for the context mode. I didn't try the other cases. Before the change: patch: 440.182u 2.049s 1:53.12 390.9% 0+0k 0+232io 4pf+0w context: 392.931u 2.164s 1:41.53 389.1% 0+0k 432+360io 5pf+0w After the change: patch: 442.182u 2.090s 1:54.13 389.2% 0+0k 0+240io 4pf+0w context: 392.742u 2.035s 1:41.37 389.4% 0+0k 0+360io 4pf+0w julia > > Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx> > --- > scripts/coccinelle/null/eno.cocci | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/scripts/coccinelle/null/eno.cocci b/scripts/coccinelle/null/eno.cocci > index 81584ff87956..969cab5116a9 100644 > --- a/scripts/coccinelle/null/eno.cocci > +++ b/scripts/coccinelle/null/eno.cocci > @@ -17,8 +17,16 @@ virtual report > @depends on patch@ > expression x,E; > @@ > - > -x = \(kmalloc\|kzalloc\|kcalloc\|kmem_cache_alloc\|kmem_cache_zalloc\|kmem_cache_alloc_node\|kmalloc_node\|kzalloc_node\)(...) > + x = > +(kzalloc > +|kmalloc > +|kcalloc > +|kmem_cache_alloc > +|kmem_cache_zalloc > +|kzalloc_node > +|kmalloc_node > +|kmem_cache_alloc_node > +)(...) > ... when != x = E > - IS_ERR(x) > + !x > @@ -27,8 +35,7 @@ x = \(kmalloc\|kzalloc\|kcalloc\|kmem_cache_alloc\|kmem_cache_zalloc\|kmem_cache > expression x,E; > position p1,p2; > @@ > - > -*x = \(kmalloc@p1\|kzalloc@p1\|kcalloc@p1\|kmem_cache_alloc@p1\|kmem_cache_zalloc@p1\|kmem_cache_alloc_node@p1\|kmalloc_node@p1\|kzalloc_node@p1\)(...) > +*x = \(kzalloc@p1\|kmalloc@p1\|kcalloc@p1\|kmem_cache_alloc@p1\|kmem_cache_zalloc@p1\|kzalloc_node@p1\|kmalloc_node@p1\|kmem_cache_alloc_node@p1\)(...) > ... when != x = E > * IS_ERR@p2(x) > > -- > 2.29.1 > > _______________________________________________ > Cocci mailing list > Cocci@xxxxxxxxxxxxxxx > https://systeme.lip6.fr/mailman/listinfo/cocci >
