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authorKeith Owens <kaos@sgi.com>2006-01-21 18:55:25 -0500
committerTony Luck <tony.luck@intel.com>2006-01-26 16:23:27 -0500
commitb0a06623dc4caf6dfb6a84419507643471676d20 (patch)
tree4808417fe23fcb3e352c0ce347abb6218fc2263e /arch/ia64/kernel/signal.c
parent3ee68c4af3fd7228c1be63254b9f884614f9ebb2 (diff)
[IA64] Delete MCA/INIT sigdelayed code
The only user of the MCA/INIT sigdelayed code (SGI's I/O probing) has moved from the kernel into SAL. Delete the MCA/INIT sigdelayed code. Signed-off-by: Keith Owens <kaos@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
Diffstat (limited to 'arch/ia64/kernel/signal.c')
-rw-r--r--arch/ia64/kernel/signal.c101
1 files changed, 0 insertions, 101 deletions
diff --git a/arch/ia64/kernel/signal.c b/arch/ia64/kernel/signal.c
index 463f6bb44d07..1d7903ee2126 100644
--- a/arch/ia64/kernel/signal.c
+++ b/arch/ia64/kernel/signal.c
@@ -588,104 +588,3 @@ ia64_do_signal (sigset_t *oldset, struct sigscratch *scr, long in_syscall)
588 } 588 }
589 return 0; 589 return 0;
590} 590}
591
592/* Set a delayed signal that was detected in MCA/INIT/NMI/PMI context where it
593 * could not be delivered. It is important that the target process is not
594 * allowed to do any more work in user space. Possible cases for the target
595 * process:
596 *
597 * - It is sleeping and will wake up soon. Store the data in the current task,
598 * the signal will be sent when the current task returns from the next
599 * interrupt.
600 *
601 * - It is running in user context. Store the data in the current task, the
602 * signal will be sent when the current task returns from the next interrupt.
603 *
604 * - It is running in kernel context on this or another cpu and will return to
605 * user context. Store the data in the target task, the signal will be sent
606 * to itself when the target task returns to user space.
607 *
608 * - It is running in kernel context on this cpu and will sleep before
609 * returning to user context. Because this is also the current task, the
610 * signal will not get delivered and the task could sleep indefinitely.
611 * Store the data in the idle task for this cpu, the signal will be sent
612 * after the idle task processes its next interrupt.
613 *
614 * To cover all cases, store the data in the target task, the current task and
615 * the idle task on this cpu. Whatever happens, the signal will be delivered
616 * to the target task before it can do any useful user space work. Multiple
617 * deliveries have no unwanted side effects.
618 *
619 * Note: This code is executed in MCA/INIT/NMI/PMI context, with interrupts
620 * disabled. It must not take any locks nor use kernel structures or services
621 * that require locks.
622 */
623
624/* To ensure that we get the right pid, check its start time. To avoid extra
625 * include files in thread_info.h, convert the task start_time to unsigned long,
626 * giving us a cycle time of > 580 years.
627 */
628static inline unsigned long
629start_time_ul(const struct task_struct *t)
630{
631 return t->start_time.tv_sec * NSEC_PER_SEC + t->start_time.tv_nsec;
632}
633
634void
635set_sigdelayed(pid_t pid, int signo, int code, void __user *addr)
636{
637 struct task_struct *t;
638 unsigned long start_time = 0;
639 int i;
640
641 for (i = 1; i <= 3; ++i) {
642 switch (i) {
643 case 1:
644 t = find_task_by_pid(pid);
645 if (t)
646 start_time = start_time_ul(t);
647 break;
648 case 2:
649 t = current;
650 break;
651 default:
652 t = idle_task(smp_processor_id());
653 break;
654 }
655
656 if (!t)
657 return;
658 task_thread_info(t)->sigdelayed.signo = signo;
659 task_thread_info(t)->sigdelayed.code = code;
660 task_thread_info(t)->sigdelayed.addr = addr;
661 task_thread_info(t)->sigdelayed.start_time = start_time;
662 task_thread_info(t)->sigdelayed.pid = pid;
663 wmb();
664 set_tsk_thread_flag(t, TIF_SIGDELAYED);
665 }
666}
667
668/* Called from entry.S when it detects TIF_SIGDELAYED, a delayed signal that
669 * was detected in MCA/INIT/NMI/PMI context where it could not be delivered.
670 */
671
672void
673do_sigdelayed(void)
674{
675 struct siginfo siginfo;
676 pid_t pid;
677 struct task_struct *t;
678
679 clear_thread_flag(TIF_SIGDELAYED);
680 memset(&siginfo, 0, sizeof(siginfo));
681 siginfo.si_signo = current_thread_info()->sigdelayed.signo;
682 siginfo.si_code = current_thread_info()->sigdelayed.code;
683 siginfo.si_addr = current_thread_info()->sigdelayed.addr;
684 pid = current_thread_info()->sigdelayed.pid;
685 t = find_task_by_pid(pid);
686 if (!t)
687 return;
688 if (current_thread_info()->sigdelayed.start_time != start_time_ul(t))
689 return;
690 force_sig_info(siginfo.si_signo, &siginfo, t);
691}