Messages in this thread | | | Subject | Re: 2.6.36-rc3 suspend issue (was: 2.6.35-rc4 / X201 issues) | From | Peter Zijlstra <> | Date | Fri, 10 Sep 2010 09:48:40 +0200 |
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On Fri, 2010-09-10 at 13:36 +0800, Jeff Chua wrote:
> > I've bisected and it's pointing to the following commit causing the > errors after resume. Reverting the commit solves the problem.
"the errors" being those at the end of this email?
> commit cd7240c0b900eb6d690ccee088a6c9b46dae815a > Author: Suresh Siddha <suresh.b.siddha@intel.com> > Date: Thu Aug 19 17:03:38 2010 -0700 > > x86, tsc, sched: Recompute cyc2ns_offset's during resume from sleep states >
> diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h > index c042729..1ca132f 100644 > --- a/arch/x86/include/asm/tsc.h > +++ b/arch/x86/include/asm/tsc.h > @@ -59,5 +59,7 @@ extern void check_tsc_sync_source(int cpu); > extern void check_tsc_sync_target(void); > > extern int notsc_setup(char *); > +extern void save_sched_clock_state(void); > +extern void restore_sched_clock_state(void); > > #endif /* _ASM_X86_TSC_H */ > diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c > index ce8e502..d632934 100644 > --- a/arch/x86/kernel/tsc.c > +++ b/arch/x86/kernel/tsc.c > @@ -626,6 +626,44 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu) > local_irq_restore(flags); > } > > +static unsigned long long cyc2ns_suspend; > + > +void save_sched_clock_state(void) > +{ > + if (!sched_clock_stable) > + return; > + > + cyc2ns_suspend = sched_clock(); > +} > + > +/* > + * Even on processors with invariant TSC, TSC gets reset in some the > + * ACPI system sleep states. And in some systems BIOS seem to reinit TSC to > + * arbitrary value (still sync'd across cpu's) during resume from such sleep > + * states. To cope up with this, recompute the cyc2ns_offset for each cpu so > + * that sched_clock() continues from the point where it was left off during > + * suspend. > + */ > +void restore_sched_clock_state(void) > +{ > + unsigned long long offset; > + unsigned long flags; > + int cpu; > + > + if (!sched_clock_stable) > + return; > + > + local_irq_save(flags); > + > + get_cpu_var(cyc2ns_offset) = 0; > + offset = cyc2ns_suspend - sched_clock(); > + > + for_each_possible_cpu(cpu) > + per_cpu(cyc2ns_offset, cpu) = offset; > + > + local_irq_restore(flags); > +} > + > #ifdef CONFIG_CPU_FREQ > > /* Frequency scaling support. Adjust the TSC based timer when the cpu frequency > diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c > index e7e8c5f..87bb35e 100644 > --- a/arch/x86/power/cpu.c > +++ b/arch/x86/power/cpu.c > @@ -113,6 +113,7 @@ static void __save_processor_state(struct saved_context *ctxt) > void save_processor_state(void) > { > __save_processor_state(&saved_context); > + save_sched_clock_state(); > } > #ifdef CONFIG_X86_32 > EXPORT_SYMBOL(save_processor_state); > @@ -229,6 +230,7 @@ static void __restore_processor_state(struct saved_context *ctxt) > void restore_processor_state(void) > { > __restore_processor_state(&saved_context); > + restore_sched_clock_state(); > } > #ifdef CONFIG_X86_32 > EXPORT_SYMBOL(restore_processor_state); > > > > > Errors like the one below: > > cpi_ds_exec_end_op+0x8e/0x3cd > [<ffffffff8121497d>] ? acpi_ps_parse_loop+0x7dd/0x96c > [<ffffffff81213af7>] ? acpi_ps_parse_aml+0x8e/0x29a > [<ffffffff8121512e>] ? acpi_ps_execute_method+0x1bf/0x28d > [<ffffffff81210741>] ? acpi_ns_evaluate+0xdd/0x19a > [<ffffffff812101f3>] ? acpi_evaluate_object+0x145/0x246 > [<ffffffff811f79b2>] ? acpi_os_signal_semaphore+0x23/0x27 > [<ffffffff811fa41e>] ? acpi_device_resume+0x0/0x2b > [<ffffffff81222892>] ? acpi_battery_get_state+0x7f/0x121 > [<ffffffff812118c2>] ? acpi_get_handle+0x7b/0x99 > [<ffffffff81222b99>] ? acpi_battery_update+0x265/0x26e > [<ffffffff81222c70>] ? acpi_battery_resume+0x25/0x2a > [<ffffffff81295c8d>] ? legacy_resume+0x1e/0x55 > [<ffffffff81295d24>] ? device_resume+0x60/0xdd > [<ffffffff811c2102>] ? kobject_get+0x12/0x17 > [<ffffffff812963e1>] ? dpm_resume_end+0xf2/0x349 > [<ffffffff8105c9a4>] ? suspend_devices_and_enter+0x15b/0x188 > [<ffffffff8105ca6a>] ? enter_state+0x99/0xcb > [<ffffffff8105c2da>] ? state_store+0xb1/0xcf > [<ffffffff810e9f0f>] ? sysfs_write_file+0xd6/0x112 > [<ffffffff810a2f82>] ? vfs_write+0xad/0x132 > [<ffffffff810a30bd>] ? sys_write+0x45/0x6e > [<ffffffff81001f02>] ? system_call_fastpath+0x16/0x1b > BUG: scheduling while atomic: lid/2486/0x00000002 >
That just doesn't make any sense, the TSC restore code doesn't involve acpi, nor does it actually schedule.
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