On Tue, 19 May 2009, Shaohua Li wrote: > When AMD C1E is enabled, local APIC timer will stop even in C1. To avoid > suspend/resume hang, this patch removes C1 and replace it with a cpu_relax() in > suspend/resume path. This hasn't any impact in runtime path. > > http://bugzilla.kernel.org/show_bug.cgi?id=13233 > > [ impact: avoid suspend/resume hang in AMD CPU with C1E enabled ] > > Tested-by: Dmitry Lyzhyn <thisistempbox@xxxxxxxxx> > Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx> > --- > drivers/acpi/processor_idle.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > Index: linux/drivers/acpi/processor_idle.c > =================================================================== > --- linux.orig/drivers/acpi/processor_idle.c 2009-05-19 09:56:59.000000000 +0800 > +++ linux/drivers/acpi/processor_idle.c 2009-05-19 10:01:23.000000000 +0800 > @@ -834,8 +834,8 @@ static int acpi_idle_enter_c1(struct cpu > > /* Do not access any ACPI IO ports in suspend path */ > if (acpi_idle_suspend) { > - acpi_safe_halt(); > local_irq_enable(); > + cpu_relax(); > return 0; > } Hmm, we removed the pm_idle_safe logic which took care of that in older kernel versions :( if (!cx || acpi_idle_suspend) { if (pm_idle_save) pm_idle_save(); else acpi_safe_halt(); return; } That's what took care of the broadcast on those AMD C1E machines as well. But yeah, that cpu_relax() loop is probably fine for the suspend path. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
