[Xenomai-git] Jan Kiszka : nucleus: Return from xnpod_suspend_thread(XNRELAX) with interrupt disabled
Module: xenomai-head
Branch: master
Commit: ef290da5e838a66df7a04539d7a77a6b0b820936
URL:
http://git.xenomai.org/?p=xenomai-head.git;a=commit;h=ef290da5e838a66df7a04539d7a77a6b0b820936
Author: Jan Kiszka
Date: Sat Jun 18 15:49:50 2011 +0200
nucleus: Return from xnpod_suspend_thread(XNRELAX) with interrupt disabled
This cleans up the special handling of XNRELAX in xnpod_suspend_thread a
bit: Instead of re-enabling the interrupts when returning to a relaxed
thread, move that code to xnshadow_relax. Saves some explanations.
Signed-off-by: Jan Kiszka
---
ksrc/nucleus/pod.c|9 +++--
ksrc/nucleus/shadow.c | 11 +++
2 files changed, 6 insertions(+), 14 deletions(-)
diff --git a/ksrc/nucleus/pod.c b/ksrc/nucleus/pod.c
index a98d9b7..9f75092 100644
--- a/ksrc/nucleus/pod.c
+++ b/ksrc/nucleus/pod.c
@@ -1462,11 +1462,9 @@ void xnpod_suspend_thread(xnthread_t *thread, xnflags_t
mask,
* have been called from xnshadow_relax(), in which
* case we introduce an opportunity for interrupt
* delivery right before switching context, which
-* shortens the uninterruptible code path. This
-* particular caller expects us to always return with
-* interrupts enabled.
+* shortens the uninterruptible code path.
*
-* We have to shut irqs off around xnpod_schedule()
+* We have to shut irqs off before xnpod_schedule()
* though: if an interrupt could preempt us in
* __xnpod_schedule right after the call to
* xnarch_escalate but before we lock the nklock, we
@@ -1478,9 +1476,8 @@ void xnpod_suspend_thread(xnthread_t *thread, xnflags_t
mask,
if (mask & XNRELAX) {
xnlock_clear_irqon(&nklock);
- splhigh(s);
+ splmax();
xnpod_schedule();
- splexit(s);
return;
}
/*
diff --git a/ksrc/nucleus/shadow.c b/ksrc/nucleus/shadow.c
index 2189d1a..9f82fa8 100644
--- a/ksrc/nucleus/shadow.c
+++ b/ksrc/nucleus/shadow.c
@@ -1094,20 +1094,15 @@ void xnshadow_relax(int notify, int reason)
* xnpod_suspend_thread() when switching out the current
* thread, not to break basic assumptions we do there.
*
-* We disable interrupts here to initiate the migration
-* sequence, and let xnpod_suspend_thread() enable them back
-* before returning to us.
+* We disable interrupts during the migration sequence, but
+* xnpod_suspend_thread() has an interrupts-on section built in.
*/
splmax();
rpi_push(thread->sched, thread);
schedule_linux_call(LO_WAKEUP_REQ, current, 0);
clear_task_nowakeup(current);
xnpod_suspend_thread(thread, XNRELAX, XN_INFINITE, XN_RELATIVE, NULL);
- /*
-* As a special case when switching out a relaxed thread,
-* interrupts have been re-enabled before returning to us. See
-* xnpod_suspend_thread().
-*/
+ splnone();
if (XENO_DEBUG(NUCLEUS) && rthal_current_domain != rthal_root_domain)
xnpod_fatal("xnshadow_relax() failed for thread %s[%d]",
thread->name, xnthread_user_pid(thread));
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[Xenomai-git] Jan Kiszka : nucleus: Return from xnpod_suspend_thread(XNRELAX) with interrupt disabled
Module: xenomai-jki
Branch: for-upstream
Commit: 8c3abce47b0c5e381c35d7fd26ea129547413e3c
URL:
http://git.xenomai.org/?p=xenomai-jki.git;a=commit;h=8c3abce47b0c5e381c35d7fd26ea129547413e3c
Author: Jan Kiszka
Date: Sat Jun 18 15:49:50 2011 +0200
nucleus: Return from xnpod_suspend_thread(XNRELAX) with interrupt disabled
This cleans up the special handling of XNRELAX in xnpod_suspend_thread a
bit: Instead of re-enabling the interrupts when returning to a relaxed
thread, move that code to xnshadow_relax. Saves some explanations.
Signed-off-by: Jan Kiszka
---
ksrc/nucleus/pod.c|9 +++--
ksrc/nucleus/shadow.c | 11 +++
2 files changed, 6 insertions(+), 14 deletions(-)
diff --git a/ksrc/nucleus/pod.c b/ksrc/nucleus/pod.c
index f2fa7c8..d33701d 100644
--- a/ksrc/nucleus/pod.c
+++ b/ksrc/nucleus/pod.c
@@ -1462,11 +1462,9 @@ void xnpod_suspend_thread(xnthread_t *thread, xnflags_t
mask,
* have been called from xnshadow_relax(), in which
* case we introduce an opportunity for interrupt
* delivery right before switching context, which
-* shortens the uninterruptible code path. This
-* particular caller expects us to always return with
-* interrupts enabled.
+* shortens the uninterruptible code path.
*
-* We have to shut irqs off around xnpod_schedule()
+* We have to shut irqs off before xnpod_schedule()
* though: if an interrupt could preempt us in
* __xnpod_schedule right after the call to
* xnarch_escalate but before we lock the nklock, we
@@ -1478,9 +1476,8 @@ void xnpod_suspend_thread(xnthread_t *thread, xnflags_t
mask,
if (mask & XNRELAX) {
xnlock_clear_irqon(&nklock);
- splhigh(s);
+ splmax();
xnpod_schedule();
- splexit(s);
return;
}
/*
diff --git a/ksrc/nucleus/shadow.c b/ksrc/nucleus/shadow.c
index 2189d1a..9f82fa8 100644
--- a/ksrc/nucleus/shadow.c
+++ b/ksrc/nucleus/shadow.c
@@ -1094,20 +1094,15 @@ void xnshadow_relax(int notify, int reason)
* xnpod_suspend_thread() when switching out the current
* thread, not to break basic assumptions we do there.
*
-* We disable interrupts here to initiate the migration
-* sequence, and let xnpod_suspend_thread() enable them back
-* before returning to us.
+* We disable interrupts during the migration sequence, but
+* xnpod_suspend_thread() has an interrupts-on section built in.
*/
splmax();
rpi_push(thread->sched, thread);
schedule_linux_call(LO_WAKEUP_REQ, current, 0);
clear_task_nowakeup(current);
xnpod_suspend_thread(thread, XNRELAX, XN_INFINITE, XN_RELATIVE, NULL);
- /*
-* As a special case when switching out a relaxed thread,
-* interrupts have been re-enabled before returning to us. See
-* xnpod_suspend_thread().
-*/
+ splnone();
if (XENO_DEBUG(NUCLEUS) && rthal_current_domain != rthal_root_domain)
xnpod_fatal("xnshadow_relax() failed for thread %s[%d]",
thread->name, xnthread_user_pid(thread));
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