forked from Minki/linux
023d377914
The memory barrier in wakeup_source_deactivate() is supposed to prevent the callers of pm_wakeup_pending() and pm_get_wakeup_count() from seeing the new value of events_in_progress (0, in particular) and the old value of event_count at the same time. However, if wakeup_source_deactivate() is executed by CPU0 and, for instance, pm_wakeup_pending() is executed by CPU1, where both processors can reorder operations, the memory barrier in wakeup_source_deactivate() doesn't affect CPU1 which can reorder reads. In that case CPU1 may very well decide to fetch event_count before it's modified and events_in_progress after it's been updated, so pm_wakeup_pending() may fail to detect a wakeup event. This issue can be addressed by using a single atomic variable to store both events_in_progress and event_count, so that they can be updated together in a single atomic operation. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> |
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| .. | ||
| power | ||
| attribute_container.c | ||
| base.h | ||
| bus.c | ||
| class.c | ||
| core.c | ||
| cpu.c | ||
| dd.c | ||
| devres.c | ||
| devtmpfs.c | ||
| dma-coherent.c | ||
| dma-mapping.c | ||
| driver.c | ||
| firmware_class.c | ||
| firmware.c | ||
| hypervisor.c | ||
| init.c | ||
| iommu.c | ||
| isa.c | ||
| Kconfig | ||
| Makefile | ||
| map.c | ||
| memory.c | ||
| module.c | ||
| node.c | ||
| platform.c | ||
| sys.c | ||
| topology.c | ||
| transport_class.c | ||