diff options
Diffstat (limited to 'arch/ia64/kernel/entry.S')
| -rw-r--r-- | arch/ia64/kernel/entry.S | 26 |
1 files changed, 16 insertions, 10 deletions
diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S index e49ad8c5dc69..ca2bb95726de 100644 --- a/arch/ia64/kernel/entry.S +++ b/arch/ia64/kernel/entry.S @@ -1156,6 +1156,9 @@ skip_rbs_switch: * r31 = current->thread_info->flags * On exit: * p6 = TRUE if work-pending-check needs to be redone + * + * Interrupts are disabled on entry, reenabled depend on work, and + * disabled on exit. */ .work_pending_syscall: add r2=-8,r2 @@ -1164,16 +1167,16 @@ skip_rbs_switch: st8 [r2]=r8 st8 [r3]=r10 .work_pending: - tbit.z p6,p0=r31,TIF_NEED_RESCHED // current_thread_info()->need_resched==0? + tbit.z p6,p0=r31,TIF_NEED_RESCHED // is resched not needed? (p6) br.cond.sptk.few .notify #ifdef CONFIG_PREEMPT (pKStk) dep r21=-1,r0,PREEMPT_ACTIVE_BIT,1 ;; (pKStk) st4 [r20]=r21 - ssm psr.i // enable interrupts #endif + ssm psr.i // enable interrupts br.call.spnt.many rp=schedule -.ret9: cmp.eq p6,p0=r0,r0 // p6 <- 1 +.ret9: cmp.eq p6,p0=r0,r0 // p6 <- 1 (re-check) rsm psr.i // disable interrupts ;; #ifdef CONFIG_PREEMPT @@ -1182,13 +1185,13 @@ skip_rbs_switch: (pKStk) st4 [r20]=r0 // preempt_count() <- 0 #endif (pLvSys)br.cond.sptk.few .work_pending_syscall_end - br.cond.sptk.many .work_processed_kernel // re-check + br.cond.sptk.many .work_processed_kernel .notify: (pUStk) br.call.spnt.many rp=notify_resume_user -.ret10: cmp.ne p6,p0=r0,r0 // p6 <- 0 +.ret10: cmp.ne p6,p0=r0,r0 // p6 <- 0 (don't re-check) (pLvSys)br.cond.sptk.few .work_pending_syscall_end - br.cond.sptk.many .work_processed_kernel // don't re-check + br.cond.sptk.many .work_processed_kernel .work_pending_syscall_end: adds r2=PT(R8)+16,r12 @@ -1196,7 +1199,7 @@ skip_rbs_switch: ;; ld8 r8=[r2] ld8 r10=[r3] - br.cond.sptk.many .work_processed_syscall // re-check + br.cond.sptk.many .work_processed_syscall END(ia64_leave_kernel) @@ -1234,9 +1237,12 @@ GLOBAL_ENTRY(ia64_invoke_schedule_tail) END(ia64_invoke_schedule_tail) /* - * Setup stack and call do_notify_resume_user(). Note that pSys and pNonSys need to - * be set up by the caller. We declare 8 input registers so the system call - * args get preserved, in case we need to restart a system call. + * Setup stack and call do_notify_resume_user(), keeping interrupts + * disabled. + * + * Note that pSys and pNonSys need to be set up by the caller. + * We declare 8 input registers so the system call args get preserved, + * in case we need to restart a system call. */ ENTRY(notify_resume_user) .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8) |