powerpc/ps3: Fix lost SMP IPIs
authorGeoff Levand <geoff@infradead.org>
Tue, 8 Nov 2011 12:37:26 +0000 (12:37 +0000)
committerGreg Kroah-Hartman <gregkh@suse.de>
Mon, 21 Nov 2011 22:35:26 +0000 (14:35 -0800)
commit9c24bb2008643ecd7588a20fd5ac7e8491f7c5d4
tree98b61435dd4060aa488aaabebc0b7a86d6be4df2
parent8bb72ab63d58957270b2dc31e6c9bcfa38470d2c
powerpc/ps3: Fix lost SMP IPIs

commit 72f3bea075287785ed32b777b6dd2636aa7002e8 upstream.

Fixes the PS3 bootup hang introduced in 3.0-rc1 by:

  commit 317f394160e9beb97d19a84c39b7e5eb3d7815a
  sched: Move the second half of ttwu() to the remote cpu

Move the PS3's LV1 EOI call lv1_end_of_interrupt_ext() from ps3_chip_eoi()
to ps3_get_irq() for IPI messages.

If lv1_send_event_locally() is called between a previous call to
lv1_send_event_locally() and the coresponding call to
lv1_end_of_interrupt_ext() the second event will not be delivered to the
target cpu.

The PS3's SMP IPIs are implemented using lv1_send_event_locally(), so if two
IPI messages of the same type are sent to the same target in a relatively
short period of time the second IPI event can become lost when
lv1_end_of_interrupt_ext() is called from ps3_chip_eoi().

Signed-off-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
arch/powerpc/platforms/ps3/interrupt.c
arch/powerpc/platforms/ps3/platform.h
arch/powerpc/platforms/ps3/smp.c