On Sat, Jul 04, 2020 at 06:44:53PM +0100, Ramsay Jones wrote: > > Hi Luc, > > All of the patches in this series look good to me! ;-) > > (I have been following all patches on the list, I just > haven't had anything to say about them - which is a good thing!) Hi, Yes, indeed. Thank you! > On 04/07/2020 14:57, Luc Van Oostenryck wrote: > > The 'Z' asm constraint is used for doing IO accessors on PPC but > > isn't part of the 'common constraints'. It's responsible for > > more than half of all warnings (with defconfig + allyesconfig). > > Not a problem, but this made me think 'half of which warnings'. :-D > I assume, but it's just a guess, this means 'half of all asm-constraints > warnings on the kernel PPC build'. > > How many warnings is that? What percentage is that of _all_ sparse > warnings on a typical kernel build? It's literally more than half of all warnings issued by sparse when doing a build of the kernel with 'defconfig' and another one with 'allyesconfig' (all my tests on kernel builds are done like so) on a ppc64 machine: $ grep ': \(error\|warning\):' log-master-master | wc -l 138581 $ grep ': \(error\|warning\):' log-arch-asm-mem | wc -l 50006 So, this series eliminates about 64% of all warnings, a nice improvement of the S/N ratio. Now, most of these warnings are exactly the same, again and again: $ diff -U1 log-master-master log-arch-asm-mem --- log-master-master 2020-07-04 14:40:56.733110303 +0200 +++ log-arch-asm-mem 2020-07-04 15:46:47.972595182 +0200 @@ -1 +1 @@ -SPARSE=fa1539620 +SPARSE=69fedae3e @@ -24,8 +23,0 @@ -./arch/powerpc/include/asm/io.h:143:1: warning: dereference of noderef expression -./arch/powerpc/include/asm/io.h:144:1: warning: dereference of noderef expression -./arch/powerpc/include/asm/io.h:148:1: warning: dereference of noderef expression -./arch/powerpc/include/asm/io.h:149:1: warning: dereference of noderef expression -./arch/powerpc/include/asm/io.h:143:1: warning: dereference of noderef expression -./arch/powerpc/include/asm/io.h:144:1: warning: dereference of noderef expression -./arch/powerpc/include/asm/io.h:148:1: warning: dereference of noderef expression -./arch/powerpc/include/asm/io.h:149:1: warning: dereference of noderef expression @@ -41 +32,0 @@ -./arch/powerpc/include/asm/io.h:144:1: warning: dereference of noderef expression @@ -56,4 +46,0 @@ -./arch/powerpc/include/asm/io.h:143:1: warning: dereference of noderef expression -./arch/powerpc/include/asm/io.h:144:1: warning: dereference of noderef expression -./arch/powerpc/include/asm/io.h:148:1: warning: dereference of noderef expression -./arch/powerpc/include/asm/io.h:149:1: warning: dereference of noderef expression ... If you count only unique warnings, the result is quite different: @gcc203:~/dev $ grep ': \(error\|warning\):' log-master-master | sort -u | wc -l 19071 @gcc203:~/dev $ grep ': \(error\|warning\):' log-arch-asm-mem | sort -u | wc -l 19067 Only 4 unique warnings are eliminated. For comparison, on x86_64 the warnings are: $ grep ': \(error\|warning\):' log-master-master | wc -l 29806 $ grep ': \(error\|warning\):' log-master-master | sort -u | wc -l 19234 > Thanks! > > [BTW, I also noticed the (long running) 'luc/options' branch, which > looks like it could prove to be a nice cleanup - I've only read the > commit messages, not the actual commits.] Yes, I think it's a nice cleanup because this code is quite messy but, OTOH, moving around all this code break all its history (via 'git blame' or 'git log -L') is is guaranteed to create really nasty conflicts with anything touching the code for the options. This is really a downside. Best regards, -- Luc
