> -----Original Message----- > From: Brendan Higgins > > On Tue, Aug 27, 2019 at 3:00 PM shuah <shuah@xxxxxxxxxx> wrote: > > > > On 8/27/19 3:36 PM, Brendan Higgins wrote: > > > On Tue, Aug 27, 2019 at 2:09 PM Brendan Higgins > > > <brendanhiggins@xxxxxxxxxx> wrote: > > >> > > >> On Tue, Aug 27, 2019 at 2:03 PM Brendan Higgins > > >> <brendanhiggins@xxxxxxxxxx> wrote: > > >>> > > >>> On Tue, Aug 27, 2019 at 1:21 PM shuah <shuah@xxxxxxxxxx> wrote: > > >>>> > > >>>> On 8/27/19 11:49 AM, Brendan Higgins wrote: > > >>>>> Previously KUnit assumed that printk would always be present, > which is > > >>>>> not a valid assumption to make. Fix that by ifdefing out functions > which > > >>>>> directly depend on printk core functions similar to what dev_printk > > >>>>> does. > > >>>>> > > >>>>> Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> > > >>>>> Link: https://lore.kernel.org/linux-kselftest/0352fae9-564f-4a97- > 715a-fabe016259df@xxxxxxxxxx/T/#t > > >>>>> Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> > > >>>>> Signed-off-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx> > > >>>>> --- > > >>>>> include/kunit/test.h | 7 +++++++ > > >>>>> kunit/test.c | 41 ++++++++++++++++++++++++----------------- > > >>>>> 2 files changed, 31 insertions(+), 17 deletions(-) > > >>>>> > > >>>>> diff --git a/include/kunit/test.h b/include/kunit/test.h > > >>>>> index 8b7eb03d4971..339af5f95c4a 100644 > > >>>>> --- a/include/kunit/test.h > > >>>>> +++ b/include/kunit/test.h > > >>>>> @@ -339,9 +339,16 @@ static inline void *kunit_kzalloc(struct kunit > *test, size_t size, gfp_t gfp) > > >>> [...] > > >>>> Okay after reviewing this, I am not sure why you need to do all > > >>>> this. > > >>>> > > >>>> Why can't you just change the root function that throws the warn: > > >>>> > > >>>> static int kunit_vprintk_emit(int level, const char *fmt, va_list args) > > >>>> { > > >>>> return vprintk_emit(0, level, NULL, 0, fmt, args); > > >>>> } > > >>>> > > >>>> You aren'r really doing anything extra here, other than calling > > >>>> vprintk_emit() > > >>> > > >>> Yeah, I did that a while ago. I think it was a combination of trying > > >>> to avoid an extra layer of adding and then removing the log level, and > > >>> that's what dev_printk and friends did. > > >>> > > >>> But I think you are probably right. It's a lot of maintenance overhead > > >>> to get rid of that. Probably best to just use what the printk people > > >>> have. > > >>> > > >>>> Unless I am missing something, can't you solve this problem by > including > > >>>> printk.h and let it handle the !CONFIG_PRINTK case? > > >>> > > >>> Randy, I hope you don't mind, but I am going to ask you to re-ack my > > >>> next revision since it basically addresses the problem in a totally > > >>> different way. > > >> > > >> Actually, scratch that. Checkpatch doesn't like me calling printk > > >> without using a KERN_<LEVEL>. > > >> > > >> Now that I am thinking back to when I wrote this. I think it also > > >> might not like using a dynamic KERN_<LEVEL> either (printk("%s my > > >> message", KERN_INFO)). > > >> > > >> I am going to have to do some more investigation. > > > > > > Alright, I am pretty sure it is safe to do printk("%smessage", > KERN_<LEVEL>); > > > > > > Looking at the printk implementation, it appears to do the format > > > before it checks the log level: > > > > > > > https://elixir.bootlin.com/linux/v5.2.10/source/kernel/printk/printk.c#L1907 > > > > > > So I am pretty sure we can do it either with the vprintk_emit or with > printk. > > > > Let me see if we are on the same page first. I am asking if you can > > just include printk.h for vprintk_emit() define for both CONFIG_PRINTK > > and !CONFIG_PRINTK cases. > > Ah sorry, I misunderstood you. > > No, that doesn't work. I tried including linux/printk.h, and I get the > same error. > > The reason for this is that vprintk_emit() is only defined when > CONFIG_PRINTK=y: > > https://elixir.bootlin.com/linux/latest/ident/vprintk_emit Ugh. That's just a bug in include/linux/printk.h There should be a stub definition for vprintk_emit() in the #else part of #ifdef CONFIG_PRINTK. You shouldn't be dealing with whether printk is present or not in the kunit code. All the printk-related routines are supposed to evaporate themselves, based on the conditional in include/linux/printk.h That should be fixed there instead of in your code. Let me know if you'd like me to submit a patch for that. I only hesitate because your patch depends on it, and IMHO it makes more sense to include it in your batch than separately. Otherwise there's a patch race condition. -- Tim
