* [PATCH] bitops: use the same mechanism for get_count_order[_long] @ 2020-05-25 21:59 Wei Yang 2020-05-26 7:04 ` Andy Shevchenko 2020-05-30 21:22 ` Wei Yang 0 siblings, 2 replies; 4+ messages in thread From: Wei Yang @ 2020-05-25 21:59 UTC (permalink / raw) To: akpm, andriy.shevchenko, christian.brauner; +Cc: linux-kernel, Wei Yang These two functions share the same logic. Signed-off-by: Wei Yang <richard.weiyang@gmail.com> --- include/linux/bitops.h | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/include/linux/bitops.h b/include/linux/bitops.h index 5b5609e81a84..80703ef27aee 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -188,12 +188,10 @@ static inline unsigned fls_long(unsigned long l) static inline int get_count_order(unsigned int count) { - int order; + if (count == 0) + return -1; - order = fls(count) - 1; - if (count & (count - 1)) - order++; - return order; + return fls(--count); } /** -- 2.23.0 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] bitops: use the same mechanism for get_count_order[_long] 2020-05-25 21:59 [PATCH] bitops: use the same mechanism for get_count_order[_long] Wei Yang @ 2020-05-26 7:04 ` Andy Shevchenko 2020-05-26 21:57 ` Wei Yang 2020-05-30 21:22 ` Wei Yang 1 sibling, 1 reply; 4+ messages in thread From: Andy Shevchenko @ 2020-05-26 7:04 UTC (permalink / raw) To: Wei Yang; +Cc: akpm, christian.brauner, linux-kernel On Mon, May 25, 2020 at 09:59:58PM +0000, Wei Yang wrote: > These two functions share the same logic. So, same comment. Please, add test first, make sure it works on current kernel, then after your patch applied, and send it as a series, thanks! P.S. W/o test code looks good, but based on my experience I'm very suspicious about "small" changes that may lead to big issues. Hope you understand my point. > Signed-off-by: Wei Yang <richard.weiyang@gmail.com> > --- > include/linux/bitops.h | 8 +++----- > 1 file changed, 3 insertions(+), 5 deletions(-) > > diff --git a/include/linux/bitops.h b/include/linux/bitops.h > index 5b5609e81a84..80703ef27aee 100644 > --- a/include/linux/bitops.h > +++ b/include/linux/bitops.h > @@ -188,12 +188,10 @@ static inline unsigned fls_long(unsigned long l) > > static inline int get_count_order(unsigned int count) > { > - int order; > + if (count == 0) > + return -1; > > - order = fls(count) - 1; > - if (count & (count - 1)) > - order++; > - return order; > + return fls(--count); > } > > /** > -- > 2.23.0 > -- With Best Regards, Andy Shevchenko ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] bitops: use the same mechanism for get_count_order[_long] 2020-05-26 7:04 ` Andy Shevchenko @ 2020-05-26 21:57 ` Wei Yang 0 siblings, 0 replies; 4+ messages in thread From: Wei Yang @ 2020-05-26 21:57 UTC (permalink / raw) To: Andy Shevchenko; +Cc: Wei Yang, akpm, christian.brauner, linux-kernel On Tue, May 26, 2020 at 10:04:57AM +0300, Andy Shevchenko wrote: >On Mon, May 25, 2020 at 09:59:58PM +0000, Wei Yang wrote: >> These two functions share the same logic. > >So, same comment. Please, add test first, make sure it works on current kernel, >then after your patch applied, and send it as a series, thanks! > >P.S. W/o test code looks good, but based on my experience I'm very suspicious >about "small" changes that may lead to big issues. Hope you understand my point. > Sure, I see your point. >> Signed-off-by: Wei Yang <richard.weiyang@gmail.com> >> --- >> include/linux/bitops.h | 8 +++----- >> 1 file changed, 3 insertions(+), 5 deletions(-) >> >> diff --git a/include/linux/bitops.h b/include/linux/bitops.h >> index 5b5609e81a84..80703ef27aee 100644 >> --- a/include/linux/bitops.h >> +++ b/include/linux/bitops.h >> @@ -188,12 +188,10 @@ static inline unsigned fls_long(unsigned long l) >> >> static inline int get_count_order(unsigned int count) >> { >> - int order; >> + if (count == 0) >> + return -1; >> >> - order = fls(count) - 1; >> - if (count & (count - 1)) >> - order++; >> - return order; >> + return fls(--count); >> } >> >> /** >> -- >> 2.23.0 >> > >-- >With Best Regards, >Andy Shevchenko > -- Wei Yang Help you, Help me ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] bitops: use the same mechanism for get_count_order[_long] 2020-05-25 21:59 [PATCH] bitops: use the same mechanism for get_count_order[_long] Wei Yang 2020-05-26 7:04 ` Andy Shevchenko @ 2020-05-30 21:22 ` Wei Yang 1 sibling, 0 replies; 4+ messages in thread From: Wei Yang @ 2020-05-30 21:22 UTC (permalink / raw) To: Wei Yang; +Cc: akpm, andriy.shevchenko, christian.brauner, linux-kernel Andrew, Would you mind picking up this one? The test module doesn't show any warning after this on applied. On Mon, May 25, 2020 at 09:59:58PM +0000, Wei Yang wrote: >These two functions share the same logic. > >Signed-off-by: Wei Yang <richard.weiyang@gmail.com> >--- > include/linux/bitops.h | 8 +++----- > 1 file changed, 3 insertions(+), 5 deletions(-) > >diff --git a/include/linux/bitops.h b/include/linux/bitops.h >index 5b5609e81a84..80703ef27aee 100644 >--- a/include/linux/bitops.h >+++ b/include/linux/bitops.h >@@ -188,12 +188,10 @@ static inline unsigned fls_long(unsigned long l) > > static inline int get_count_order(unsigned int count) > { >- int order; >+ if (count == 0) >+ return -1; > >- order = fls(count) - 1; >- if (count & (count - 1)) >- order++; >- return order; >+ return fls(--count); > } > > /** >-- >2.23.0 -- Wei Yang Help you, Help me ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-05-30 21:22 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2020-05-25 21:59 [PATCH] bitops: use the same mechanism for get_count_order[_long] Wei Yang 2020-05-26 7:04 ` Andy Shevchenko 2020-05-26 21:57 ` Wei Yang 2020-05-30 21:22 ` Wei Yang
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