On Mon, 2011-12-12 at 17:10 +0800, Tiejun Chen wrote: > > -#ifdef CONFIG_PREEMPT > - clrrdi r9,r1,THREAD_SHIFT /* current_thread_info() */ > - li r0,_TIF_NEED_RESCHED /* bits to check */ > - ld r3,_MSR(r1) > - ld r4,TI_FLAGS(r9) > - /* Move MSR_PR bit in r3 to _TIF_SIGPENDING position in r0 */ > - rlwimi r0,r3,32+TIF_SIGPENDING-MSR_PR_LG,_TIF_SIGPENDING > - and. r0,r4,r0 /* check NEED_RESCHED and maybe SIGPENDING */ > - bne do_work > - > -#else /* !CONFIG_PREEMPT */ > ld r3,_MSR(r1) /* Returning to user mode? */ > andi. r3,r3,MSR_PR > - beq restore /* if not, just restore regs and return */ > + bne test_work_user
Any reason to not use restore_user / resume_kernel like ppc32 ? It might help whoever wants to look at that code in the future if we make both sides a bit closer :-) Not a big deal and if you prefer like this I don't have a firm objection > + clrrdi r9,r1,THREAD_SHIFT /* current_thread_info() */ > + li r0,_TIF_USER_WORK_MASK > +#ifdef CONFIG_PREEMPT > + ori r0,r0,_TIF_NEED_RESCHED > +#endif Why the above ? Doesn't _TIF_USER_WORK_MASK altready contain TIF_NEED_RESCHED ? Also this is the kernel path, I'd rather just define something along the lines of _TIF_KERNEL_WORK_MASK. Then, you change the definition of it based on PREEMPT, ie: #ifdef CONFIG_PREEMPT #define _TIF_KERNEL_WORK_MASK _TIF_NEED_RESCHED #else #define _TIF_KERNEL_WORK_MASK 0 #endif Now, that does mean that you'll have a useless test without PREEMPT here but ... it will stop being useless as soon as you port over the stux emulation so it's fine as a placeholder. > + ld r4,TI_FLAGS(r9) > + and. r0,r4,r0 /* check NEED_RESCHED and maybe > _TIF_USER_WORK_MASK */ > + bne do_kernel_work > + b restore /* if so, just restore regs and return */ > + > +test_work_user: > /* Check current_thread_info()->flags */ > clrrdi r9,r1,THREAD_SHIFT > ld r4,TI_FLAGS(r9) > andi. r0,r4,_TIF_USER_WORK_MASK > - bne do_work > -#endif > + bne do_user_work > > restore: > BEGIN_FW_FTR_SECTION > @@ -693,10 +692,8 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) > b .ret_from_except_lite /* loop back and handle more */ > #endif > > -do_work: > +do_kernel_work: > #ifdef CONFIG_PREEMPT > - andi. r0,r3,MSR_PR /* Returning to user mode? */ > - bne user_work > /* Check that preempt_count() == 0 and interrupts are enabled */ > lwz r8,TI_PREEMPT(r9) > cmpwi cr1,r8,0 > @@ -738,9 +735,9 @@ do_work: > bne 1b > b restore > > -user_work: > #endif /* CONFIG_PREEMPT */ > > +do_user_work: > /* Enable interrupts */ > #ifdef CONFIG_PPC_BOOK3E > wrteei 1 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
