From 3fac10145b766a2244422788f62dc35978613fd8 Mon Sep 17 00:00:00 2001 From: Ben Guthro Date: Wed, 17 Apr 2013 09:18:49 -0400 Subject: [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 [v3: Ate some tabs, s/printk/pr_info/] Signed-off-by: Konrad Rzeszutek Wilk --- 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..e2a5333 100644 --- a/drivers/xen/xen-acpi-processor.c +++ b/drivers/xen/xen-acpi-processor.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include #include @@ -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; + + pr_info(DRV_NAME "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); -- 2.7.4