Messages in this thread | | | From | Andy Shevchenko <> | Date | Thu, 19 Nov 2020 17:16:32 +0200 | Subject | Re: Proposal for a new checkpatch check; matching _set_drvdata() & _get_drvdata() |
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On Thu, Nov 19, 2020 at 4:09 PM Alexandru Ardelean <ardeleanalex@gmail.com> wrote: > > Hey, > > So, I stumbled on a new check that could be added to checkpatch. > Since it's in Perl, I'm reluctant to try it. > > Seems many drivers got to a point where they now call (let's say) > spi_set_drvdata(), but never access that information via > spi_get_drvdata(). > Reasons for this seem to be: > 1. They got converted to device-managed functions and there is no > longer a remove hook to require the _get_drvdata() access > 2. They look like they were copied from a driver that had a > _set_drvdata() and when the code got finalized, the _set_drvdata() was > omitted > > There are a few false positives that I can notice at a quick look, > like the data being set via some xxx_set_drvdata() and retrieved via a > dev_get_drvdata().
I can say quite a few. And this makes a difference. So, basically all drivers that are using PM callbacks would rather use dev_get_drvdata() rather than bus specific.
> I think checkpatch reporting these as well would be acceptable simply > from a reviewability perspective. > > I did a shell script to quickly check these. See below. > It's pretty badly written but it is enough for me to gather a list. > And I wrote it in 5 minutes :P > I initially noticed this in some IIO drivers, and then I suspected > that this may be more widespread.
It seems more suitable for coccinelle.
> The shell script gathers a list of xxx_set_drvdata() functions then > greps through all files and also checks if there are any matching > xxx_get_drvdata(). > > Thanks > Alex > > Shell script: > ----------------------------------------------------------------------- > #!/bin/bash > > fns1=$(git grep _set_drvdata | cut -d: -f2 | cut -d'(' -f1 | sort -u) > > for fn in $fns1 ; do > if [ "$fn" == "//pci_set_drvdata" ] ; then > continue > fi > if [ "$fn" == '``dev_set_drvdata' ] ; then > continue > fi > if [ "$fn" == '"pci_set_drvdata' ] ; then > continue > fi > if [[ "$fn" == *"_set_drvdata" ]]; then > fns2="$fns2 $fn" > fi > done > > fns1=$(echo $fns2 | tr ' ' '\n' | sort -u | tr '\n' ' ') > > for fn in $fns1 ; do > get_fn=$(echo $fn | sed 's/_set_/_get_/g') > > echo "Matching $fn - $get_fn" > for file in $(git grep $fn | cut -d: -f1 | sort -u) ; do > if ! grep -q $get_fn $file ; then > echo " Maybe $file" > fi > done > done > -----------------------------------------------------------------------
-- With Best Regards, Andy Shevchenko
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