Atsushi Nemoto wrote: > On Wed, 2 Jul 2008 10:59:56 +0100, Thiemo Seufer <ths@xxxxxxxxxxxx> wrote: > > > --- a/include/asm-mips/atomic.h 2008-06-25 22:38:43.159739000 -0700 > > > +++ b/include/asm-mips/atomic.h 2008-06-25 22:39:07.552065000 -0700 > > > @@ -292,10 +292,10 @@ static __inline__ int atomic_sub_if_posi > > > " beqz %0, 2f \n" > > > " subu %0, %1, %3 \n" > > > " .set reorder \n" > > > - "1: \n" > > > " .subsection 2 \n" > > > "2: b 1b \n" > > > " .previous \n" > > > + "1: \n" > > > > AFAICS this change should make no difference to the generated code. I > > suspect you assembler handles .subsection incorrectly. Can you provide > > a disassembled exapmle which gets altered by this patch? Also, please > > tell us the exact version of the assembler you use. > > Why no defference? The '1b' in subsection refer backword '1' label on > the source code (which is a label for LL insn in this case with the > patch) ? Oh. Now that you spelled it out I see it, too. :-) > Anyway I can provide them. I'm using vanilla 2.17 and 2.18. > > Without the patch: > 801233bc <try_acquire_console_sem>: > 801233bc: lui v0,0x8038 > 801233c0: ll a0,31976(v0) > 801233c4: addiu v1,a0,-1 > 801233c8: bltz v1,801233dc <try_acquire_console_sem+0x20> > 801233cc: nop > 801233d0: sc v1,31976(v0) > 801233d4: beqz v1,80124dac <sys_syslog+0x8> > 801233d8: addiu v1,a0,-1 > 801233dc: bltz v1,801233fc <try_acquire_console_sem+0x40> > 801233e0: li v0,-1 > ... > 80124dac: b 801233dc <try_acquire_console_sem+0x20> > 80124db0: nop > > With the patch: > 801233bc <try_acquire_console_sem>: > 801233bc: lui v0,0x8038 > 801233c0: ll a0,31976(v0) > 801233c4: addiu v1,a0,-1 > 801233c8: bltz v1,801233dc <try_acquire_console_sem+0x20> > 801233cc: nop > 801233d0: sc v1,31976(v0) > 801233d4: beqz v1,80124dac <sys_syslog+0x8> > 801233d8: addiu v1,a0,-1 > 801233dc: bltz v1,801233fc <try_acquire_console_sem+0x40> > 801233e0: li v0,-1 > ... > 80124dac: b 801233c0 <try_acquire_console_sem+0x4> > 80124db0: nop > > > The patch looks correct. Agreed. Thiemo
