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authorMarcelo Tosatti <mtosatti@redhat.com>2012-11-28 01:28:55 (GMT)
committerMarcelo Tosatti <mtosatti@redhat.com>2012-11-28 01:29:09 (GMT)
commit71056ae22d43f58d7e0f793af18ace2eaf5b74eb (patch)
tree02433f7fac25fbbb18405a0fe7a2b5f9925d3610 /arch
parent582b336ec2c0f0076f5650a029fcc9abd4a906f7 (diff)
downloadlinux-71056ae22d43f58d7e0f793af18ace2eaf5b74eb.tar.xz
x86: pvclock: generic pvclock vsyscall initialization
Originally from Jeremy Fitzhardinge. Introduce generic, non hypervisor specific, pvclock initialization routines. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/include/asm/clocksource.h1
-rw-r--r--arch/x86/include/asm/fixmap.h5
-rw-r--r--arch/x86/include/asm/pvclock.h12
-rw-r--r--arch/x86/kernel/pvclock.c73
4 files changed, 91 insertions, 0 deletions
diff --git a/arch/x86/include/asm/clocksource.h b/arch/x86/include/asm/clocksource.h
index 0bdbbb3..16a57f4 100644
--- a/arch/x86/include/asm/clocksource.h
+++ b/arch/x86/include/asm/clocksource.h
@@ -8,6 +8,7 @@
#define VCLOCK_NONE 0 /* No vDSO clock available. */
#define VCLOCK_TSC 1 /* vDSO should use vread_tsc. */
#define VCLOCK_HPET 2 /* vDSO should use vread_hpet. */
+#define VCLOCK_PVCLOCK 3 /* vDSO should use vread_pvclock. */
struct arch_clocksource_data {
int vclock_mode;
diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h
index 4da3c0c..a09c285 100644
--- a/arch/x86/include/asm/fixmap.h
+++ b/arch/x86/include/asm/fixmap.h
@@ -19,6 +19,7 @@
#include <asm/acpi.h>
#include <asm/apicdef.h>
#include <asm/page.h>
+#include <asm/pvclock.h>
#ifdef CONFIG_X86_32
#include <linux/threads.h>
#include <asm/kmap_types.h>
@@ -81,6 +82,10 @@ enum fixed_addresses {
VVAR_PAGE,
VSYSCALL_HPET,
#endif
+#ifdef CONFIG_PARAVIRT_CLOCK
+ PVCLOCK_FIXMAP_BEGIN,
+ PVCLOCK_FIXMAP_END = PVCLOCK_FIXMAP_BEGIN+PVCLOCK_VSYSCALL_NR_PAGES-1,
+#endif
FIX_DBGP_BASE,
FIX_EARLYCON_MEM_BASE,
#ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h
index 63f9167..109a9dd 100644
--- a/arch/x86/include/asm/pvclock.h
+++ b/arch/x86/include/asm/pvclock.h
@@ -91,4 +91,16 @@ unsigned __pvclock_read_cycles(const struct pvclock_vcpu_time_info *src,
return version;
}
+struct pvclock_vsyscall_time_info {
+ struct pvclock_vcpu_time_info pvti;
+ u32 migrate_count;
+} __attribute__((__aligned__(SMP_CACHE_BYTES)));
+
+#define PVTI_SIZE sizeof(struct pvclock_vsyscall_time_info)
+#define PVCLOCK_VSYSCALL_NR_PAGES (((NR_CPUS-1)/(PAGE_SIZE/PVTI_SIZE))+1)
+
+int __init pvclock_init_vsyscall(struct pvclock_vsyscall_time_info *i,
+ int size);
+struct pvclock_vcpu_time_info *pvclock_get_vsyscall_time_info(int cpu);
+
#endif /* _ASM_X86_PVCLOCK_H */
diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c
index c8fb043..85c3959 100644
--- a/arch/x86/kernel/pvclock.c
+++ b/arch/x86/kernel/pvclock.c
@@ -17,6 +17,11 @@
#include <linux/kernel.h>
#include <linux/percpu.h>
+#include <linux/notifier.h>
+#include <linux/sched.h>
+#include <linux/gfp.h>
+#include <linux/bootmem.h>
+#include <asm/fixmap.h>
#include <asm/pvclock.h>
static u8 valid_flags __read_mostly = 0;
@@ -122,3 +127,71 @@ void pvclock_read_wallclock(struct pvclock_wall_clock *wall_clock,
set_normalized_timespec(ts, now.tv_sec, now.tv_nsec);
}
+
+static struct pvclock_vsyscall_time_info *pvclock_vdso_info;
+
+static struct pvclock_vsyscall_time_info *
+pvclock_get_vsyscall_user_time_info(int cpu)
+{
+ if (!pvclock_vdso_info) {
+ BUG();
+ return NULL;
+ }
+
+ return &pvclock_vdso_info[cpu];
+}
+
+struct pvclock_vcpu_time_info *pvclock_get_vsyscall_time_info(int cpu)
+{
+ return &pvclock_get_vsyscall_user_time_info(cpu)->pvti;
+}
+
+#ifdef CONFIG_X86_64
+static int pvclock_task_migrate(struct notifier_block *nb, unsigned long l,
+ void *v)
+{
+ struct task_migration_notifier *mn = v;
+ struct pvclock_vsyscall_time_info *pvti;
+
+ pvti = pvclock_get_vsyscall_user_time_info(mn->from_cpu);
+
+ /* this is NULL when pvclock vsyscall is not initialized */
+ if (unlikely(pvti == NULL))
+ return NOTIFY_DONE;
+
+ pvti->migrate_count++;
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block pvclock_migrate = {
+ .notifier_call = pvclock_task_migrate,
+};
+
+/*
+ * Initialize the generic pvclock vsyscall state. This will allocate
+ * a/some page(s) for the per-vcpu pvclock information, set up a
+ * fixmap mapping for the page(s)
+ */
+
+int __init pvclock_init_vsyscall(struct pvclock_vsyscall_time_info *i,
+ int size)
+{
+ int idx;
+
+ WARN_ON (size != PVCLOCK_VSYSCALL_NR_PAGES*PAGE_SIZE);
+
+ pvclock_vdso_info = i;
+
+ for (idx = 0; idx <= (PVCLOCK_FIXMAP_END-PVCLOCK_FIXMAP_BEGIN); idx++) {
+ __set_fixmap(PVCLOCK_FIXMAP_BEGIN + idx,
+ __pa_symbol(i) + (idx*PAGE_SIZE),
+ PAGE_KERNEL_VVAR);
+ }
+
+
+ register_task_migration_notifier(&pvclock_migrate);
+
+ return 0;
+}
+#endif