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) ? 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. --- Atsushi Nemoto
