Jan Beulich
2012-Sep-24 11:02 UTC
[PATCH] x86: fix MWAIT-based idle driver for CPUs without ARAT
lapic_timer_{on,off} need to get initialized in this case. This in turn
requires getting HPET broadcast setup to be carried out earlier (and
hence preventing double initialization there).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
Note that I don''t have a respective system available to test these
adjustments (which is also why I didn''t notice the omission from the
original patch), so I can only hope that this works and takes care of
the observed boot failure.
--- a/xen/arch/x86/acpi/cpu_idle.c
+++ b/xen/arch/x86/acpi/cpu_idle.c
@@ -74,6 +74,29 @@ static void lapic_timer_nop(void) { }
void (*__read_mostly lapic_timer_off)(void);
void (*__read_mostly lapic_timer_on)(void);
+bool_t lapic_timer_init(void)
+{
+ if ( boot_cpu_has(X86_FEATURE_ARAT) )
+ {
+ lapic_timer_off = lapic_timer_nop;
+ lapic_timer_on = lapic_timer_nop;
+ }
+ else if ( hpet_broadcast_is_available() )
+ {
+ lapic_timer_off = hpet_broadcast_enter;
+ lapic_timer_on = hpet_broadcast_exit;
+ }
+ else if ( pit_broadcast_is_available() )
+ {
+ lapic_timer_off = pit_broadcast_enter;
+ lapic_timer_on = pit_broadcast_exit;
+ }
+ else
+ return 0;
+
+ return 1;
+}
+
static uint64_t (*__read_mostly tick_to_ns)(uint64_t) = acpi_pm_tick_to_ns;
void (*__read_mostly pm_idle_save)(void);
@@ -789,25 +812,8 @@ static int check_cx(struct acpi_processo
if ( local_apic_timer_c2_ok )
break;
case ACPI_STATE_C3:
- if ( boot_cpu_has(X86_FEATURE_ARAT) )
- {
- lapic_timer_off = lapic_timer_nop;
- lapic_timer_on = lapic_timer_nop;
- }
- else if ( hpet_broadcast_is_available() )
- {
- lapic_timer_off = hpet_broadcast_enter;
- lapic_timer_on = hpet_broadcast_exit;
- }
- else if ( pit_broadcast_is_available() )
- {
- lapic_timer_off = pit_broadcast_enter;
- lapic_timer_on = pit_broadcast_exit;
- }
- else
- {
+ if ( !lapic_timer_init() )
return -EINVAL;
- }
/* All the logic here assumes flags.bm_check is same across all CPUs */
if ( bm_check_flag == -1 )
--- a/xen/arch/x86/cpu/mwait-idle.c
+++ b/xen/arch/x86/cpu/mwait-idle.c
@@ -56,6 +56,7 @@
#include <xen/softirq.h>
#include <xen/trace.h>
#include <asm/cpuidle.h>
+#include <asm/hpet.h>
#include <asm/mwait.h>
#include <asm/msr.h>
#include <acpi/cpufreq/cpufreq.h>
@@ -501,6 +502,12 @@ int __init mwait_idle_init(struct notifi
err = mwait_idle_probe();
if (!err) {
+ if (!boot_cpu_has(X86_FEATURE_ARAT))
+ hpet_broadcast_init();
+ if (!lapic_timer_init())
+ err = -EINVAL;
+ }
+ if (!err) {
nfb->notifier_call = mwait_idle_cpu_init;
mwait_idle_cpu_init(nfb, CPU_UP_PREPARE, NULL);
--- a/xen/arch/x86/hpet.c
+++ b/xen/arch/x86/hpet.c
@@ -495,7 +495,7 @@ void __init hpet_broadcast_init(void)
u32 hpet_id, cfg;
unsigned int i, n;
- if ( hpet_rate == 0 )
+ if ( hpet_rate == 0 || hpet_broadcast_is_available() )
return;
cfg = hpet_read32(HPET_CFG);
--- a/xen/include/asm-x86/cpuidle.h
+++ b/xen/include/asm-x86/cpuidle.h
@@ -10,6 +10,7 @@ extern struct acpi_processor_power *proc
extern void (*pm_idle_save)(void);
+bool_t lapic_timer_init(void);
extern void (*lapic_timer_off)(void);
extern void (*lapic_timer_on)(void);
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Keir Fraser
2012-Sep-25 14:10 UTC
Re: [PATCH] x86: fix MWAIT-based idle driver for CPUs without ARAT
On 24/09/2012 12:02, "Jan Beulich" <JBeulich@suse.com> wrote:> lapic_timer_{on,off} need to get initialized in this case. This in turn > requires getting HPET broadcast setup to be carried out earlier (and > hence preventing double initialization there). > > Signed-off-by: Jan Beulich <jbeulich@suse.com>Acked-by: Keir Fraser <keir@xen.org>> --- > Note that I don''t have a respective system available to test these > adjustments (which is also why I didn''t notice the omission from the > original patch), so I can only hope that this works and takes care of > the observed boot failure. > > --- a/xen/arch/x86/acpi/cpu_idle.c > +++ b/xen/arch/x86/acpi/cpu_idle.c > @@ -74,6 +74,29 @@ static void lapic_timer_nop(void) { } > void (*__read_mostly lapic_timer_off)(void); > void (*__read_mostly lapic_timer_on)(void); > > +bool_t lapic_timer_init(void) > +{ > + if ( boot_cpu_has(X86_FEATURE_ARAT) ) > + { > + lapic_timer_off = lapic_timer_nop; > + lapic_timer_on = lapic_timer_nop; > + } > + else if ( hpet_broadcast_is_available() ) > + { > + lapic_timer_off = hpet_broadcast_enter; > + lapic_timer_on = hpet_broadcast_exit; > + } > + else if ( pit_broadcast_is_available() ) > + { > + lapic_timer_off = pit_broadcast_enter; > + lapic_timer_on = pit_broadcast_exit; > + } > + else > + return 0; > + > + return 1; > +} > + > static uint64_t (*__read_mostly tick_to_ns)(uint64_t) = acpi_pm_tick_to_ns; > > void (*__read_mostly pm_idle_save)(void); > @@ -789,25 +812,8 @@ static int check_cx(struct acpi_processo > if ( local_apic_timer_c2_ok ) > break; > case ACPI_STATE_C3: > - if ( boot_cpu_has(X86_FEATURE_ARAT) ) > - { > - lapic_timer_off = lapic_timer_nop; > - lapic_timer_on = lapic_timer_nop; > - } > - else if ( hpet_broadcast_is_available() ) > - { > - lapic_timer_off = hpet_broadcast_enter; > - lapic_timer_on = hpet_broadcast_exit; > - } > - else if ( pit_broadcast_is_available() ) > - { > - lapic_timer_off = pit_broadcast_enter; > - lapic_timer_on = pit_broadcast_exit; > - } > - else > - { > + if ( !lapic_timer_init() ) > return -EINVAL; > - } > > /* All the logic here assumes flags.bm_check is same across all CPUs > */ > if ( bm_check_flag == -1 ) > --- a/xen/arch/x86/cpu/mwait-idle.c > +++ b/xen/arch/x86/cpu/mwait-idle.c > @@ -56,6 +56,7 @@ > #include <xen/softirq.h> > #include <xen/trace.h> > #include <asm/cpuidle.h> > +#include <asm/hpet.h> > #include <asm/mwait.h> > #include <asm/msr.h> > #include <acpi/cpufreq/cpufreq.h> > @@ -501,6 +502,12 @@ int __init mwait_idle_init(struct notifi > > err = mwait_idle_probe(); > if (!err) { > + if (!boot_cpu_has(X86_FEATURE_ARAT)) > + hpet_broadcast_init(); > + if (!lapic_timer_init()) > + err = -EINVAL; > + } > + if (!err) { > nfb->notifier_call = mwait_idle_cpu_init; > mwait_idle_cpu_init(nfb, CPU_UP_PREPARE, NULL); > > --- a/xen/arch/x86/hpet.c > +++ b/xen/arch/x86/hpet.c > @@ -495,7 +495,7 @@ void __init hpet_broadcast_init(void) > u32 hpet_id, cfg; > unsigned int i, n; > > - if ( hpet_rate == 0 ) > + if ( hpet_rate == 0 || hpet_broadcast_is_available() ) > return; > > cfg = hpet_read32(HPET_CFG); > --- a/xen/include/asm-x86/cpuidle.h > +++ b/xen/include/asm-x86/cpuidle.h > @@ -10,6 +10,7 @@ extern struct acpi_processor_power *proc > > extern void (*pm_idle_save)(void); > > +bool_t lapic_timer_init(void); > extern void (*lapic_timer_off)(void); > extern void (*lapic_timer_on)(void); > > > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel