Ben Guthro
2013-Apr-17 13:18 UTC
[PATCH] xen: Re-upload processor PM data to hypervisor after S3 resume (v2)
Upon resume, it was found that ACPI C-states were missing from non-boot CPUs.
This change registers a syscore_ops handler for this case, and re-uploads the
PM information to the hypervisor to properly reset the C-state on these
processors.
v2:
v1 did not go through the check_acpi_ids() code-path, and missed some cases when
xen was running with the dom0_max_vcpus= command line parameter.
Signed-Off-By: Ben Guthro <benjamin.guthro@citrix.com>
---
drivers/xen/xen-acpi-processor.c | 78 ++++++++++++++++++++++++++------------
1 file changed, 53 insertions(+), 25 deletions(-)
diff --git a/drivers/xen/xen-acpi-processor.c b/drivers/xen/xen-acpi-processor.c
index 90e34ac..86b6f69 100644
--- a/drivers/xen/xen-acpi-processor.c
+++ b/drivers/xen/xen-acpi-processor.c
@@ -25,6 +25,7 @@
#include <linux/init.h>
#include <linux/module.h>
#include <linux/types.h>
+#include <linux/syscore_ops.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#include <acpi/processor.h>
@@ -51,9 +52,9 @@ static DEFINE_MUTEX(acpi_ids_mutex);
/* Which ACPI ID we have processed from ''struct
acpi_processor''. */
static unsigned long *acpi_ids_done;
/* Which ACPI ID exist in the SSDT/DSDT processor definitions. */
-static unsigned long __initdata *acpi_id_present;
+static unsigned long *acpi_id_present;
/* And if there is an _CST definition (or a PBLK) for the ACPI IDs */
-static unsigned long __initdata *acpi_id_cst_present;
+static unsigned long *acpi_id_cst_present;
static int push_cxx_to_hypervisor(struct acpi_processor *_pr)
{
@@ -390,6 +391,10 @@ static int __init check_acpi_ids(struct acpi_processor
*pr_backup)
if (!pr_backup)
return -ENODEV;
+ if (acpi_id_present && acpi_id_cst_present)
+ /* OK, done this once .. skip to uploading */
+ goto upload;
+
/* All online CPUs have been processed at this stage. Now verify
* whether in fact "online CPUs" == physical CPUs.
*/
@@ -408,6 +413,7 @@ static int __init check_acpi_ids(struct acpi_processor
*pr_backup)
read_acpi_id, NULL, NULL, NULL);
acpi_get_devices("ACPI0007", read_acpi_id, NULL, NULL);
+upload:
if (!bitmap_equal(acpi_id_present, acpi_ids_done, nr_acpi_bits)) {
unsigned int i;
for_each_set_bit(i, acpi_id_present, nr_acpi_bits) {
@@ -417,10 +423,7 @@ static int __init check_acpi_ids(struct acpi_processor
*pr_backup)
(void)upload_pm_data(pr_backup);
}
}
- kfree(acpi_id_present);
- acpi_id_present = NULL;
- kfree(acpi_id_cst_present);
- acpi_id_cst_present = NULL;
+
return 0;
}
static int __init check_prereq(void)
@@ -467,10 +470,47 @@ static void free_acpi_perf_data(void)
free_percpu(acpi_perf_data);
}
-static int __init xen_acpi_processor_init(void)
+static int xen_upload_processor_pm_data(void)
{
struct acpi_processor *pr_backup = NULL;
unsigned int i;
+ int rc = 0;
+
+ printk(KERN_INFO "Uploading Xen processor pm info\n");
+
+ for_each_possible_cpu(i) {
+ struct acpi_processor *_pr;
+ _pr = per_cpu(processors, i /* APIC ID */);
+ if (!_pr)
+ continue;
+
+ if (!pr_backup) {
+ pr_backup = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
+ if (pr_backup)
+ memcpy(pr_backup, _pr, sizeof(struct acpi_processor));
+ }
+ (void)upload_pm_data(_pr);
+ }
+
+ rc = check_acpi_ids(pr_backup);
+ kfree(pr_backup);
+
+ return rc;
+}
+
+static void xen_acpi_processor_resume(void)
+{
+ bitmap_zero(acpi_ids_done, nr_acpi_bits);
+ xen_upload_processor_pm_data();
+}
+
+static struct syscore_ops xap_syscore_ops = {
+ .resume = xen_acpi_processor_resume,
+};
+
+static int __init xen_acpi_processor_init(void)
+{
+ unsigned int i;
int rc = check_prereq();
if (rc)
@@ -514,27 +554,12 @@ static int __init xen_acpi_processor_init(void)
goto err_out;
}
- for_each_possible_cpu(i) {
- struct acpi_processor *_pr;
- _pr = per_cpu(processors, i /* APIC ID */);
- if (!_pr)
- continue;
-
- if (!pr_backup) {
- pr_backup = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
- if (pr_backup)
- memcpy(pr_backup, _pr, sizeof(struct acpi_processor));
- }
- (void)upload_pm_data(_pr);
- }
- rc = check_acpi_ids(pr_backup);
-
- kfree(pr_backup);
- pr_backup = NULL;
-
+ rc = xen_upload_processor_pm_data();
if (rc)
goto err_unregister;
+ register_syscore_ops(&xap_syscore_ops);
+
return 0;
err_unregister:
for_each_possible_cpu(i) {
@@ -552,7 +577,10 @@ static void __exit xen_acpi_processor_exit(void)
{
int i;
+ unregister_syscore_ops(&xap_syscore_ops);
kfree(acpi_ids_done);
+ kfree(acpi_id_present);
+ kfree(acpi_id_cst_present);
for_each_possible_cpu(i) {
struct acpi_processor_performance *perf;
perf = per_cpu_ptr(acpi_perf_data, i);
--
1.7.9.5