WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

[Xen-devel] [111/264] genirq: Add IRQF_RESUME_EARLY and resume such IRQs

To: linux-kernel@xxxxxxxxxxxxxxx, stable@xxxxxxxxxxxxxxx
Subject: [Xen-devel] [111/264] genirq: Add IRQF_RESUME_EARLY and resume such IRQs earlier
From: Greg KH <gregkh@xxxxxxx>
Date: Wed, 09 Nov 2011 13:32:38 -0800
Cc: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@xxxxxxxxxx>, Ian Campbell <ian.campbell@xxxxxxxxxx>, Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>, "Rafael J. Wysocki" <rjw@xxxxxxx>, xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>, akpm@xxxxxxxxxxxxxxxxxxxx, torvalds@xxxxxxxxxxxxxxxxxxxx, Thomas Gleixner <tglx@xxxxxxxxxxxxx>, alan@xxxxxxxxxxxxxxxxxxx
Delivery-date: Wed, 09 Nov 2011 19:41:15 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <20111109213508.GA3476@xxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: quilt/0.48-16.4
3.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Ian Campbell <ian.campbell@xxxxxxxxxx>

commit 9bab0b7fbaceec47d32db51cd9e59c82fb071f5a upstream.

This adds a mechanism to resume selected IRQs during syscore_resume
instead of dpm_resume_noirq.

Under Xen we need to resume IRQs associated with IPIs early enough
that the resched IPI is unmasked and we can therefore schedule
ourselves out of the stop_machine where the suspend/resume takes
place.

This issue was introduced by 676dc3cf5bc3 "xen: Use IRQF_FORCE_RESUME".

Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
Cc: Rafael J. Wysocki <rjw@xxxxxxx>
Cc: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@xxxxxxxxxx>
Cc: xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1318713254.11016.52.camel@xxxxxxxxxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 drivers/xen/events.c      |    2 -
 include/linux/interrupt.h |    3 ++
 kernel/irq/pm.c           |   48 +++++++++++++++++++++++++++++++++++++++-------
 3 files changed, 45 insertions(+), 8 deletions(-)

--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -1021,7 +1021,7 @@ int bind_ipi_to_irqhandler(enum ipi_vect
        if (irq < 0)
                return irq;
 
-       irqflags |= IRQF_NO_SUSPEND | IRQF_FORCE_RESUME;
+       irqflags |= IRQF_NO_SUSPEND | IRQF_FORCE_RESUME | IRQF_EARLY_RESUME;
        retval = request_irq(irq, handler, irqflags, devname, dev_id);
        if (retval != 0) {
                unbind_from_irq(irq);
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -59,6 +59,8 @@
  * IRQF_NO_SUSPEND - Do not disable this IRQ during suspend
  * IRQF_FORCE_RESUME - Force enable it on resume even if IRQF_NO_SUSPEND is set
  * IRQF_NO_THREAD - Interrupt cannot be threaded
+ * IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device
+ *                resume time.
  */
 #define IRQF_DISABLED          0x00000020
 #define IRQF_SAMPLE_RANDOM     0x00000040
@@ -72,6 +74,7 @@
 #define IRQF_NO_SUSPEND                0x00004000
 #define IRQF_FORCE_RESUME      0x00008000
 #define IRQF_NO_THREAD         0x00010000
+#define IRQF_EARLY_RESUME      0x00020000
 
 #define IRQF_TIMER             (__IRQF_TIMER | IRQF_NO_SUSPEND | 
IRQF_NO_THREAD)
 
--- a/kernel/irq/pm.c
+++ b/kernel/irq/pm.c
@@ -9,6 +9,7 @@
 #include <linux/irq.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
+#include <linux/syscore_ops.h>
 
 #include "internals.h"
 
@@ -39,25 +40,58 @@ void suspend_device_irqs(void)
 }
 EXPORT_SYMBOL_GPL(suspend_device_irqs);
 
-/**
- * resume_device_irqs - enable interrupt lines disabled by 
suspend_device_irqs()
- *
- * Enable all interrupt lines previously disabled by suspend_device_irqs() that
- * have the IRQS_SUSPENDED flag set.
- */
-void resume_device_irqs(void)
+static void resume_irqs(bool want_early)
 {
        struct irq_desc *desc;
        int irq;
 
        for_each_irq_desc(irq, desc) {
                unsigned long flags;
+               bool is_early = desc->action &&
+                       desc->action->flags & IRQF_EARLY_RESUME;
+
+               if (is_early != want_early)
+                       continue;
 
                raw_spin_lock_irqsave(&desc->lock, flags);
                __enable_irq(desc, irq, true);
                raw_spin_unlock_irqrestore(&desc->lock, flags);
        }
 }
+
+/**
+ * irq_pm_syscore_ops - enable interrupt lines early
+ *
+ * Enable all interrupt lines with %IRQF_EARLY_RESUME set.
+ */
+static void irq_pm_syscore_resume(void)
+{
+       resume_irqs(true);
+}
+
+static struct syscore_ops irq_pm_syscore_ops = {
+       .resume         = irq_pm_syscore_resume,
+};
+
+static int __init irq_pm_init_ops(void)
+{
+       register_syscore_ops(&irq_pm_syscore_ops);
+       return 0;
+}
+
+device_initcall(irq_pm_init_ops);
+
+/**
+ * resume_device_irqs - enable interrupt lines disabled by 
suspend_device_irqs()
+ *
+ * Enable all non-%IRQF_EARLY_RESUME interrupt lines previously
+ * disabled by suspend_device_irqs() that have the IRQS_SUSPENDED flag
+ * set as well as those with %IRQF_FORCE_RESUME.
+ */
+void resume_device_irqs(void)
+{
+       resume_irqs(false);
+}
 EXPORT_SYMBOL_GPL(resume_device_irqs);
 
 /**



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-devel] [111/264] genirq: Add IRQF_RESUME_EARLY and resume such IRQs earlier, Greg KH <=