--- v5
+++ v3
@@ -1,58 +1,21 @@
This patch applies the introduced memalloc_noio_save() and
memalloc_noio_restore() to force memory allocation with no I/O
-during runtime_resume/runtime_suspend callback on device with
-the flag of 'memalloc_noio' set.
+during runtime_resume callback on device which is marked as
+memalloc_noio_resume.
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oneukum@suse.de>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
---
-v5:
- - use inline memalloc_noio_save()
-v4:
- - runtime_suspend need this too because rpm_resume may wait for
- completion of concurrent runtime_suspend, so deadlock still may
- be triggered in runtime_suspend path.
----
- drivers/base/power/runtime.c | 32 ++++++++++++++++++++++++++++++--
- 1 file changed, 30 insertions(+), 2 deletions(-)
+ drivers/base/power/runtime.c | 16 +++++++++++++++-
+ 1 file changed, 15 insertions(+), 1 deletion(-)
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
-index 3e198a0..96d99ea 100644
+index 9fa6ea7..c9e26b9 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
-@@ -371,6 +371,7 @@ static int rpm_suspend(struct device *dev, int rpmflags)
- int (*callback)(struct device *);
- struct device *parent = NULL;
- int retval;
-+ unsigned int noio_flag;
-
- trace_rpm_suspend(dev, rpmflags);
-
-@@ -480,7 +481,20 @@ static int rpm_suspend(struct device *dev, int rpmflags)
- if (!callback && dev->driver && dev->driver->pm)
- callback = dev->driver->pm->runtime_suspend;
-
-- retval = rpm_callback(callback, dev);
-+ /*
-+ * Deadlock might be caused if memory allocation with GFP_KERNEL
-+ * happens inside runtime_suspend callback of one block device's
-+ * ancestor or the block device itself. Network device might be
-+ * thought as part of iSCSI block device, so network device and
-+ * its ancestor should be marked as memalloc_noio.
-+ */
-+ if (dev->power.memalloc_noio) {
-+ noio_flag = memalloc_noio_save();
-+ retval = rpm_callback(callback, dev);
-+ memalloc_noio_restore(noio_flag);
-+ } else {
-+ retval = rpm_callback(callback, dev);
-+ }
- if (retval)
- goto fail;
-
-@@ -563,6 +577,7 @@ static int rpm_resume(struct device *dev, int rpmflags)
+@@ -575,6 +575,7 @@ static int rpm_resume(struct device *dev, int rpmflags)
int (*callback)(struct device *);
struct device *parent = NULL;
int retval = 0;
@@ -60,7 +23,7 @@
trace_rpm_resume(dev, rpmflags);
-@@ -712,7 +727,20 @@ static int rpm_resume(struct device *dev, int rpmflags)
+@@ -724,7 +725,20 @@ static int rpm_resume(struct device *dev, int rpmflags)
if (!callback && dev->driver && dev->driver->pm)
callback = dev->driver->pm->runtime_resume;
@@ -70,10 +33,10 @@
+ * happens inside runtime_resume callback of one block device's
+ * ancestor or the block device itself. Network device might be
+ * thought as part of iSCSI block device, so network device and
-+ * its ancestor should be marked as memalloc_noio.
++ * its ancestor should be marked as memalloc_noio_resume.
+ */
-+ if (dev->power.memalloc_noio) {
-+ noio_flag = memalloc_noio_save();
++ if (dev->power.memalloc_noio_resume) {
++ memalloc_noio_save(noio_flag);
+ retval = rpm_callback(callback, dev);
+ memalloc_noio_restore(noio_flag);
+ } else {