x86/vdso: Use generic VDSO clock mode storage

Switch to the generic VDSO clock mode storage.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> (VDSO parts)
Acked-by: Juergen Gross <jgross@suse.com> (Xen parts)
Acked-by: Paolo Bonzini <pbonzini@redhat.com> (KVM parts)
Link: https://lkml.kernel.org/r/20200207124403.152039903@linutronix.de

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index beea770..698e9c8 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -57,7 +57,6 @@ config X86
        select ACPI_LEGACY_TABLES_LOOKUP        if ACPI
        select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
        select ARCH_32BIT_OFF_T                 if X86_32
-       select ARCH_CLOCKSOURCE_DATA
        select ARCH_CLOCKSOURCE_INIT
        select ARCH_HAS_ACPI_TABLE_UPGRADE      if ACPI
        select ARCH_HAS_DEBUG_VIRTUAL
@@ -126,6 +125,7 @@ config X86
        select GENERIC_STRNLEN_USER
        select GENERIC_TIME_VSYSCALL
        select GENERIC_GETTIMEOFDAY
+       select GENERIC_VDSO_CLOCK_MODE
        select GENERIC_VDSO_TIME_NS
        select GUP_GET_PTE_LOW_HIGH             if X86_PAE
        select HARDLOCKUP_CHECK_TIMESTAMP       if X86_64

diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index cce3e80..43428cc 100644 (file)
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -221,7 +221,7 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
        } else if (sym_offset == image->sym_pvclock_page) {
                struct pvclock_vsyscall_time_info *pvti =
                        pvclock_get_pvti_cpu0_va();
-               if (pvti && vclock_was_used(VCLOCK_PVCLOCK)) {
+               if (pvti && vclock_was_used(VDSO_CLOCKMODE_PVCLOCK)) {
                        return vmf_insert_pfn_prot(vma, vmf->address,
                                        __pa(pvti) >> PAGE_SHIFT,
                                        pgprot_decrypted(vma->vm_page_prot));
@@ -229,7 +229,7 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
        } else if (sym_offset == image->sym_hvclock_page) {
                struct ms_hyperv_tsc_page *tsc_pg = hv_get_tsc_page();
 
-               if (tsc_pg && vclock_was_used(VCLOCK_HVCLOCK))
+               if (tsc_pg && vclock_was_used(VDSO_CLOCKMODE_HVCLOCK))
                        return vmf_insert_pfn(vma, vmf->address,
                                        virt_to_phys(tsc_pg) >> PAGE_SHIFT);
        } else if (sym_offset == image->sym_timens_page) {
@@ -447,7 +447,7 @@ __setup("vdso=", vdso_setup);
 
 static int __init init_vdso(void)
 {
-       BUILD_BUG_ON(VCLOCK_MAX >= 32);
+       BUILD_BUG_ON(VDSO_CLOCKMODE_MAX >= 32);
 
        init_vdso_image(&vdso_image_64);
 

diff --git a/arch/x86/include/asm/clocksource.h b/arch/x86/include/asm/clocksource.h
index 2450d6e..d561db6 100644 (file)
--- a/arch/x86/include/asm/clocksource.h
+++ b/arch/x86/include/asm/clocksource.h
@@ -4,15 +4,10 @@
 #ifndef _ASM_X86_CLOCKSOURCE_H
 #define _ASM_X86_CLOCKSOURCE_H
 
-#define VCLOCK_NONE    0       /* No vDSO clock available.             */
-#define VCLOCK_TSC     1       /* vDSO should use vread_tsc.           */
-#define VCLOCK_PVCLOCK 2       /* vDSO should use vread_pvclock.       */
-#define VCLOCK_HVCLOCK 3       /* vDSO should use vread_hvclock.       */
-#define VCLOCK_MAX     3
-
-struct arch_clocksource_data {
-       int vclock_mode;
-};
+#define VDSO_ARCH_CLOCKMODES   \
+       VDSO_CLOCKMODE_TSC,     \
+       VDSO_CLOCKMODE_PVCLOCK, \
+       VDSO_CLOCKMODE_HVCLOCK
 
 extern unsigned int vclocks_used;
 

diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index f7cbc01..edc2c58 100644 (file)
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -46,9 +46,9 @@ typedef int (*hyperv_fill_flush_list_func)(
 #define hv_set_reference_tsc(val) \
        wrmsrl(HV_X64_MSR_REFERENCE_TSC, val)
 #define hv_set_clocksource_vdso(val) \
-       ((val).archdata.vclock_mode = VCLOCK_HVCLOCK)
+       ((val).vdso_clock_mode = VDSO_CLOCKMODE_HVCLOCK)
 #define hv_enable_vdso_clocksource() \
-       vclocks_set_used(VCLOCK_HVCLOCK);
+       vclocks_set_used(VDSO_CLOCKMODE_HVCLOCK);
 #define hv_get_raw_timer() rdtsc_ordered()
 
 void hyperv_callback_vector(void);

diff --git a/arch/x86/include/asm/vdso/gettimeofday.h b/arch/x86/include/asm/vdso/gettimeofday.h
index 264d4fd..9a6dc9b 100644 (file)
--- a/arch/x86/include/asm/vdso/gettimeofday.h
+++ b/arch/x86/include/asm/vdso/gettimeofday.h
@@ -243,7 +243,7 @@ static u64 vread_hvclock(void)
 
 static inline u64 __arch_get_hw_counter(s32 clock_mode)
 {
-       if (likely(clock_mode == VCLOCK_TSC))
+       if (likely(clock_mode == VDSO_CLOCKMODE_TSC))
                return (u64)rdtsc_ordered();
        /*
         * For any memory-mapped vclock type, we need to make sure that gcc
@@ -252,13 +252,13 @@ static inline u64 __arch_get_hw_counter(s32 clock_mode)
         * question isn't enabled, which will segfault.  Hence the barriers.
         */
 #ifdef CONFIG_PARAVIRT_CLOCK
-       if (clock_mode == VCLOCK_PVCLOCK) {
+       if (clock_mode == VDSO_CLOCKMODE_PVCLOCK) {
                barrier();
                return vread_pvclock();
        }
 #endif
 #ifdef CONFIG_HYPERV_TIMER
-       if (clock_mode == VCLOCK_HVCLOCK) {
+       if (clock_mode == VDSO_CLOCKMODE_HVCLOCK) {
                barrier();
                return vread_hvclock();
        }

diff --git a/arch/x86/include/asm/vdso/vsyscall.h b/arch/x86/include/asm/vdso/vsyscall.h
index 01f5733..be199a9 100644 (file)
--- a/arch/x86/include/asm/vdso/vsyscall.h
+++ b/arch/x86/include/asm/vdso/vsyscall.h
@@ -21,13 +21,6 @@ struct vdso_data *__x86_get_k_vdso_data(void)
 }
 #define __arch_get_k_vdso_data __x86_get_k_vdso_data
 
-static __always_inline
-int __x86_get_clock_mode(struct timekeeper *tk)
-{
-       return tk->tkr_mono.clock->archdata.vclock_mode;
-}
-#define __arch_get_clock_mode __x86_get_clock_mode
-
 /* The asm-generic header needs to be included after the definitions above */
 #include <asm-generic/vdso/vsyscall.h>
 

diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index 33f2cac..34b18f6 100644 (file)
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -161,7 +161,7 @@ bool kvm_check_and_clear_guest_paused(void)
 
 static int kvm_cs_enable(struct clocksource *cs)
 {
-       vclocks_set_used(VCLOCK_PVCLOCK);
+       vclocks_set_used(VDSO_CLOCKMODE_PVCLOCK);
        return 0;
 }
 
@@ -279,7 +279,7 @@ static int __init kvm_setup_vsyscall_timeinfo(void)
        if (!(flags & PVCLOCK_TSC_STABLE_BIT))
                return 0;
 
-       kvm_clock.archdata.vclock_mode = VCLOCK_PVCLOCK;
+       kvm_clock.vdso_clock_mode = VDSO_CLOCKMODE_PVCLOCK;
 #endif
 
        kvmclock_init_mem();

diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c
index 1012535..11065dc 100644 (file)
--- a/arch/x86/kernel/pvclock.c
+++ b/arch/x86/kernel/pvclock.c
@@ -145,7 +145,7 @@ void pvclock_read_wallclock(struct pvclock_wall_clock *wall_clock,
 
 void pvclock_set_pvti_cpu0_va(struct pvclock_vsyscall_time_info *pvti)
 {
-       WARN_ON(vclock_was_used(VCLOCK_PVCLOCK));
+       WARN_ON(vclock_was_used(VDSO_CLOCKMODE_PVCLOCK));
        pvti_cpu0_va = pvti;
 }
 

diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c
index d8673d8..4d545db 100644 (file)
--- a/arch/x86/kernel/time.c
+++ b/arch/x86/kernel/time.c
@@ -122,18 +122,12 @@ void __init time_init(void)
  */
 void clocksource_arch_init(struct clocksource *cs)
 {
-       if (cs->archdata.vclock_mode == VCLOCK_NONE)
+       if (cs->vdso_clock_mode == VDSO_CLOCKMODE_NONE)
                return;
 
-       if (cs->archdata.vclock_mode > VCLOCK_MAX) {
-               pr_warn("clocksource %s registered with invalid vclock_mode %d. Disabling vclock.\n",
-                       cs->name, cs->archdata.vclock_mode);
-               cs->archdata.vclock_mode = VCLOCK_NONE;
-       }
-
        if (cs->mask != CLOCKSOURCE_MASK(64)) {
-               pr_warn("clocksource %s registered with invalid mask %016llx. Disabling vclock.\n",
+               pr_warn("clocksource %s registered with invalid mask %016llx for VDSO. Disabling VDSO support.\n",
                        cs->name, cs->mask);
-               cs->archdata.vclock_mode = VCLOCK_NONE;
+               cs->vdso_clock_mode = VDSO_CLOCKMODE_NONE;
        }
 }

diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 742da14..971d6f0 100644 (file)
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -1110,7 +1110,7 @@ static void tsc_cs_tick_stable(struct clocksource *cs)
 
 static int tsc_cs_enable(struct clocksource *cs)
 {
-       vclocks_set_used(VCLOCK_TSC);
+       vclocks_set_used(VDSO_CLOCKMODE_TSC);
        return 0;
 }
 
@@ -1124,7 +1124,7 @@ static struct clocksource clocksource_tsc_early = {
        .mask                   = CLOCKSOURCE_MASK(64),
        .flags                  = CLOCK_SOURCE_IS_CONTINUOUS |
                                  CLOCK_SOURCE_MUST_VERIFY,
-       .archdata               = { .vclock_mode = VCLOCK_TSC },
+       .vdso_clock_mode        = VDSO_CLOCKMODE_TSC,
        .enable                 = tsc_cs_enable,
        .resume                 = tsc_resume,
        .mark_unstable          = tsc_cs_mark_unstable,
@@ -1145,7 +1145,7 @@ static struct clocksource clocksource_tsc = {
        .flags                  = CLOCK_SOURCE_IS_CONTINUOUS |
                                  CLOCK_SOURCE_VALID_FOR_HRES |
                                  CLOCK_SOURCE_MUST_VERIFY,
-       .archdata               = { .vclock_mode = VCLOCK_TSC },
+       .vdso_clock_mode        = VDSO_CLOCKMODE_TSC,
        .enable                 = tsc_cs_enable,
        .resume                 = tsc_resume,
        .mark_unstable          = tsc_cs_mark_unstable,

diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index f194dd0..cef5a34 100644 (file)
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -815,8 +815,8 @@ TRACE_EVENT(kvm_write_tsc_offset,
 #ifdef CONFIG_X86_64
 
 #define host_clocks                                    \
-       {VCLOCK_NONE, "none"},                          \
-       {VCLOCK_TSC,  "tsc"}                            \
+       {VDSO_CLOCKMODE_NONE, "none"},                  \
+       {VDSO_CLOCKMODE_TSC,  "tsc"}                    \
 
 TRACE_EVENT(kvm_update_master_clock,
        TP_PROTO(bool use_master_clock, unsigned int host_clock, bool offset_matched),

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fb5d64e..0e7ef29 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1631,7 +1631,7 @@ static void update_pvclock_gtod(struct timekeeper *tk)
        write_seqcount_begin(&vdata->seq);
 
        /* copy pvclock gtod data */
-       vdata->clock.vclock_mode        = tk->tkr_mono.clock->archdata.vclock_mode;
+       vdata->clock.vclock_mode        = tk->tkr_mono.clock->vdso_clock_mode;
        vdata->clock.cycle_last         = tk->tkr_mono.cycle_last;
        vdata->clock.mask               = tk->tkr_mono.mask;
        vdata->clock.mult               = tk->tkr_mono.mult;
@@ -1639,7 +1639,7 @@ static void update_pvclock_gtod(struct timekeeper *tk)
        vdata->clock.base_cycles        = tk->tkr_mono.xtime_nsec;
        vdata->clock.offset             = tk->tkr_mono.base;
 
-       vdata->raw_clock.vclock_mode    = tk->tkr_raw.clock->archdata.vclock_mode;
+       vdata->raw_clock.vclock_mode    = tk->tkr_raw.clock->vdso_clock_mode;
        vdata->raw_clock.cycle_last     = tk->tkr_raw.cycle_last;
        vdata->raw_clock.mask           = tk->tkr_raw.mask;
        vdata->raw_clock.mult           = tk->tkr_raw.mult;
@@ -1840,7 +1840,7 @@ static u64 compute_guest_tsc(struct kvm_vcpu *vcpu, s64 kernel_ns)
 
 static inline int gtod_is_based_on_tsc(int mode)
 {
-       return mode == VCLOCK_TSC || mode == VCLOCK_HVCLOCK;
+       return mode == VDSO_CLOCKMODE_TSC || mode == VDSO_CLOCKMODE_HVCLOCK;
 }
 
 static void kvm_track_tsc_matching(struct kvm_vcpu *vcpu)
@@ -1933,7 +1933,7 @@ static inline bool kvm_check_tsc_unstable(void)
         * TSC is marked unstable when we're running on Hyper-V,
         * 'TSC page' clocksource is good.
         */
-       if (pvclock_gtod_data.clock.vclock_mode == VCLOCK_HVCLOCK)
+       if (pvclock_gtod_data.clock.vclock_mode == VDSO_CLOCKMODE_HVCLOCK)
                return false;
 #endif
        return check_tsc_unstable();
@@ -2088,30 +2088,30 @@ static inline u64 vgettsc(struct pvclock_clock *clock, u64 *tsc_timestamp,
        u64 tsc_pg_val;
 
        switch (clock->vclock_mode) {
-       case VCLOCK_HVCLOCK:
+       case VDSO_CLOCKMODE_HVCLOCK:
                tsc_pg_val = hv_read_tsc_page_tsc(hv_get_tsc_page(),
                                                  tsc_timestamp);
                if (tsc_pg_val != U64_MAX) {
                        /* TSC page valid */
-                       *mode = VCLOCK_HVCLOCK;
+                       *mode = VDSO_CLOCKMODE_HVCLOCK;
                        v = (tsc_pg_val - clock->cycle_last) &
                                clock->mask;
                } else {
                        /* TSC page invalid */
-                       *mode = VCLOCK_NONE;
+                       *mode = VDSO_CLOCKMODE_NONE;
                }
                break;
-       case VCLOCK_TSC:
-               *mode = VCLOCK_TSC;
+       case VDSO_CLOCKMODE_TSC:
+               *mode = VDSO_CLOCKMODE_TSC;
                *tsc_timestamp = read_tsc();
                v = (*tsc_timestamp - clock->cycle_last) &
                        clock->mask;
                break;
        default:
-               *mode = VCLOCK_NONE;
+               *mode = VDSO_CLOCKMODE_NONE;
        }
 
-       if (*mode == VCLOCK_NONE)
+       if (*mode == VDSO_CLOCKMODE_NONE)
                *tsc_timestamp = v = 0;
 
        return v * clock->mult;

diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 5d1568f..c8897aa 100644 (file)
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -147,7 +147,7 @@ static struct notifier_block xen_pvclock_gtod_notifier = {
 
 static int xen_cs_enable(struct clocksource *cs)
 {
-       vclocks_set_used(VCLOCK_PVCLOCK);
+       vclocks_set_used(VDSO_CLOCKMODE_PVCLOCK);
        return 0;
 }
 
@@ -419,12 +419,13 @@ void xen_restore_time_memory_area(void)
        ret = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_time_memory_area, 0, &t);
 
        /*
-        * We don't disable VCLOCK_PVCLOCK entirely if it fails to register the
-        * secondary time info with Xen or if we migrated to a host without the
-        * necessary flags. On both of these cases what happens is either
-        * process seeing a zeroed out pvti or seeing no PVCLOCK_TSC_STABLE_BIT
-        * bit set. Userspace checks the latter and if 0, it discards the data
-        * in pvti and fallbacks to a system call for a reliable timestamp.
+        * We don't disable VDSO_CLOCKMODE_PVCLOCK entirely if it fails to
+        * register the secondary time info with Xen or if we migrated to a
+        * host without the necessary flags. On both of these cases what
+        * happens is either process seeing a zeroed out pvti or seeing no
+        * PVCLOCK_TSC_STABLE_BIT bit set. Userspace checks the latter and
+        * if 0, it discards the data in pvti and fallbacks to a system
+        * call for a reliable timestamp.
         */
        if (ret != 0)
                pr_notice("Cannot restore secondary vcpu_time_info (err %d)",
@@ -450,7 +451,7 @@ static void xen_setup_vsyscall_time_info(void)
 
        ret = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_time_memory_area, 0, &t);
        if (ret) {
-               pr_notice("xen: VCLOCK_PVCLOCK not supported (err %d)\n", ret);
+               pr_notice("xen: VDSO_CLOCKMODE_PVCLOCK not supported (err %d)\n", ret);
                free_page((unsigned long)ti);
                return;
        }
@@ -467,14 +468,14 @@ static void xen_setup_vsyscall_time_info(void)
                if (!ret)
                        free_page((unsigned long)ti);
 
-               pr_notice("xen: VCLOCK_PVCLOCK not supported (tsc unstable)\n");
+               pr_notice("xen: VDSO_CLOCKMODE_PVCLOCK not supported (tsc unstable)\n");
                return;
        }
 
        xen_clock = ti;
        pvclock_set_pvti_cpu0_va(xen_clock);
 
-       xen_clocksource.archdata.vclock_mode = VCLOCK_PVCLOCK;
+       xen_clocksource.vdso_clock_mode = VDSO_CLOCKMODE_PVCLOCK;
 }
 
 static void __init xen_time_init(void)