> +Lsignal_return: > + ANDI32 r1, r10, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME > + beq r1, r0, restore_all > + mov r4, sp /* pt_regs */ > + SAVE_SWITCH_STACK > + call do_notify_resume > + beq r2, r0, no_work_pending > + RESTORE_SWITCH_STACK > + /* prepare restart syscall here without leaving kernel */ > + ldw r2, PT_R2(sp) /* reload syscall number in r2 */ > + ldw r4, PT_R4(sp) /* reload syscall arguments r4-r9 */ > + ldw r5, PT_R5(sp) > + ldw r6, PT_R6(sp) > + ldw r7, PT_R7(sp) > + ldw r8, PT_R8(sp) > + ldw r9, PT_R9(sp) > + br local_restart /* restart syscall */ > + > +no_work_pending: > + RESTORE_SWITCH_STACK > + br restore_all
Umm... Branch to no_work_pending will be usuall taken. How well does branch predictor on that processor cope with such things? Another thing is the point Richard made - multiple pending signals need to be handled. IOW, that should be a branch to ret_from_exception, not restore_all. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
