kvm ptp targets to provide high precision time sync between guest
and host in virtualization environment. This patch enable kvm ptp
for arm64.
This patch set base on [1][2][3]
change log:
from v5 to v6:
(1) apply Mark's patch[4] to get SMCCC conduit.
(2) add mechanism to recognize current clocksource by add
clocksouce_id value into struct clocksource instead of method in patch-v5.
(3) rename kvm_arch_ptp_get_clock_fn into
kvm_arch_ptp_get_crosststamp.
from v4 to v5:
(1) remove hvc delay compensasion as it should leave to userspace.
(2) check current clocksource in hvc call service.
(3) expose current clocksource by adding it to
system_time_snapshot.
(4) add helper to check if clocksource is arm_arch_counter.
(5) rename kvm_ptp.c to ptp_kvm_common.c
from v3 to v4:
(1) fix clocksource of ptp_kvm to arch_sys_counter.
(2) move kvm_arch_ptp_get_clock_fn into arm_arch_timer.c
(3) subtract cntvoff before return cycles from host.
(4) use ktime_get_snapshot instead of getnstimeofday and
get_current_counterval to return time and counter value.
(5) split ktime and counter into two 32-bit block respectively
to avoid Y2038-safe issue.
(6) set time compensation to device time as half of the delay of
hvc call.
(7) add ARM_ARCH_TIMER as dependency of ptp_kvm for
arm64.
from v2 to v3:
(1) fix some issues in commit log.
(2) add some receivers in send list.
from v1 to v2:
(1) move arch-specific code from arch/ to driver/ptp/
(2) offer mechanism to inform userspace if ptp_kvm service is
available.
(3) separate ptp_kvm code for arm64 into hypervisor part and
guest part.
(4) add API to expose monotonic clock and counter value.
(5) refine code: remove no necessary part and reconsitution.
[1]https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/
commit/?h=kvm/hvc&id=125ea89e4a21e2fc5235410f966a996a1a7148bf
[2]https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/
commit/?h=kvm/hvc&id=464f5a1741e5959c3e4d2be1966ae0093b4dce06
[3]https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/
commit/?h=kvm/hvc&id=6597490e005d0eeca8ed8c1c1d7b4318ee014681
[4]https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/
commit/?h=for-next/smccc-conduit-cleanup&id=6b7fe77c334ae59fed9500140e08f4f896b36871
Jianyong Wu (6):
psci: let arm_smccc_1_1_invoke available by modules
ptp: Reorganize ptp_kvm modules to make it arch-independent.
time: Add mechanism to recognize clocksource in time_get_snapshot
psci: Add hvc call service for ptp_kvm.
ptp: arm64: Enable ptp_kvm for arm64
kvm: arm64: Add capability check extension for ptp_kvm
Mark Rutland (1):
arm/arm64: smccc/psci: add arm_smccc_1_1_get_conduit()
drivers/clocksource/arm_arch_timer.c | 24 ++++++
drivers/firmware/psci/psci.c | 16 ++++
drivers/ptp/Kconfig | 2 +-
drivers/ptp/Makefile | 1 +
drivers/ptp/ptp_kvm_arm64.c | 53 +++++++++++++
drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} | 77 +++++-------------
drivers/ptp/ptp_kvm_x86.c | 87 +++++++++++++++++++++
include/asm-generic/ptp_kvm.h | 12 +++
include/clocksource/arm_arch_timer.h | 4 +
include/linux/arm-smccc.h | 30 ++++++-
include/linux/clocksource.h | 6 ++
include/linux/timekeeping.h | 12 +--
include/uapi/linux/kvm.h | 1 +
kernel/time/clocksource.c | 3 +
kernel/time/timekeeping.c | 1 +
virt/kvm/arm/arm.c | 1 +
virt/kvm/arm/psci.c | 22 ++++++
17 files changed, 286 insertions(+), 66 deletions(-)
create mode 100644 drivers/ptp/ptp_kvm_arm64.c
rename drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} (63%)
create mode 100644 drivers/ptp/ptp_kvm_x86.c
create mode 100644 include/asm-generic/ptp_kvm.h
--
2.17.1
From: Mark Rutland <[email protected]>
SMCCC callers are currently amassing a collection of enums for the SMCCC
conduit, and are having to dig into the PSCI driver's internals in order
to figure out what to do.
Let's clean this up, with common SMCCC_CONDUIT_* definitions, and an
arm_smccc_1_1_get_conduit() helper that abstracts the PSCI driver's
internal state.
We can kill off the PSCI_CONDUIT_* definitions once we've migrated users
over to the new interface.
Signed-off-by: Mark Rutland <[email protected]>
Acked-by: Lorenzo Pieralisi <[email protected]>
Acked-by: Will Deacon <[email protected]>
Signed-off-by: Catalin Marinas <[email protected]>
---
drivers/firmware/psci/psci.c | 15 +++++++++++++++
include/linux/arm-smccc.h | 16 ++++++++++++++++
2 files changed, 31 insertions(+)
diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
index f82ccd39a913..5f31f1bea1af 100644
--- a/drivers/firmware/psci/psci.c
+++ b/drivers/firmware/psci/psci.c
@@ -57,6 +57,21 @@ struct psci_operations psci_ops = {
.smccc_version = SMCCC_VERSION_1_0,
};
+enum arm_smccc_conduit arm_smccc_1_1_get_conduit(void)
+{
+ if (psci_ops.smccc_version < SMCCC_VERSION_1_1)
+ return SMCCC_CONDUIT_NONE;
+
+ switch (psci_ops.conduit) {
+ case PSCI_CONDUIT_SMC:
+ return SMCCC_CONDUIT_SMC;
+ case PSCI_CONDUIT_HVC:
+ return SMCCC_CONDUIT_HVC;
+ default:
+ return SMCCC_CONDUIT_NONE;
+ }
+}
+
typedef unsigned long (psci_fn)(unsigned long, unsigned long,
unsigned long, unsigned long);
static psci_fn *invoke_psci_fn;
diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index 552cbd49abe8..701fa1da6b4a 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -107,6 +107,22 @@
#include <linux/linkage.h>
#include <linux/types.h>
+
+enum arm_smccc_conduit {
+ SMCCC_CONDUIT_NONE,
+ SMCCC_CONDUIT_SMC,
+ SMCCC_CONDUIT_HVC,
+};
+
+/**
+ * arm_smccc_1_1_get_conduit()
+ *
+ * Returns the conduit to be used for SMCCCv1.1 or later.
+ *
+ * When SMCCCv1.1 is not present, returns SMCCC_CONDUIT_NONE.
+ */
+enum arm_smccc_conduit arm_smccc_1_1_get_conduit(void);
+
/**
* struct arm_smccc_res - Result from SMC/HVC call
* @a0-a3 result values from registers 0 to 3
--
2.17.1
Export arm_smccc_1_1_get_conduit and apply it to get conduit
in arm_smccc_1_1_invoke, then modules can use this arm_smccc_1_1_invoke.
Signed-off-by: Jianyong Wu <[email protected]>
---
drivers/firmware/psci/psci.c | 1 +
include/linux/arm-smccc.h | 2 +-
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
index 5f31f1bea1af..cf509171422c 100644
--- a/drivers/firmware/psci/psci.c
+++ b/drivers/firmware/psci/psci.c
@@ -71,6 +71,7 @@ enum arm_smccc_conduit arm_smccc_1_1_get_conduit(void)
return SMCCC_CONDUIT_NONE;
}
}
+EXPORT_SYMBOL(arm_smccc_1_1_get_conduit);
typedef unsigned long (psci_fn)(unsigned long, unsigned long,
unsigned long, unsigned long);
diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index 701fa1da6b4a..6f82c87308ed 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -373,7 +373,7 @@ asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
* The return value also provides the conduit that was used.
*/
#define arm_smccc_1_1_invoke(...) ({ \
- int method = psci_ops.conduit; \
+ int method = arm_smccc_1_1_get_conduit(); \
switch (method) { \
case PSCI_CONDUIT_HVC: \
arm_smccc_1_1_hvc(__VA_ARGS__); \
--
2.17.1
Currently, ptp_kvm modules implementation is only for x86 which includs
large part of arch-specific code. This patch move all of those code
into new arch related file in the same directory.
Signed-off-by: Jianyong Wu <[email protected]>
---
drivers/ptp/Makefile | 1 +
drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} | 77 +++++-------------
drivers/ptp/ptp_kvm_x86.c | 87 +++++++++++++++++++++
include/asm-generic/ptp_kvm.h | 12 +++
4 files changed, 118 insertions(+), 59 deletions(-)
rename drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} (63%)
create mode 100644 drivers/ptp/ptp_kvm_x86.c
create mode 100644 include/asm-generic/ptp_kvm.h
diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile
index 677d1d178a3e..3b7554f56ad9 100644
--- a/drivers/ptp/Makefile
+++ b/drivers/ptp/Makefile
@@ -4,6 +4,7 @@
#
ptp-y := ptp_clock.o ptp_chardev.o ptp_sysfs.o
+ptp_kvm-y := ptp_kvm_$(ARCH).o ptp_kvm_common.o
obj-$(CONFIG_PTP_1588_CLOCK) += ptp.o
obj-$(CONFIG_PTP_1588_CLOCK_DTE) += ptp_dte.o
obj-$(CONFIG_PTP_1588_CLOCK_IXP46X) += ptp_ixp46x.o
diff --git a/drivers/ptp/ptp_kvm.c b/drivers/ptp/ptp_kvm_common.c
similarity index 63%
rename from drivers/ptp/ptp_kvm.c
rename to drivers/ptp/ptp_kvm_common.c
index fc7d0b77e118..0cd855d475f3 100644
--- a/drivers/ptp/ptp_kvm.c
+++ b/drivers/ptp/ptp_kvm_common.c
@@ -8,12 +8,12 @@
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/slab.h>
#include <linux/module.h>
#include <uapi/linux/kvm_para.h>
#include <asm/kvm_para.h>
-#include <asm/pvclock.h>
-#include <asm/kvmclock.h>
#include <uapi/asm/kvm_para.h>
+#include <asm-generic/ptp_kvm.h>
#include <linux/ptp_clock_kernel.h>
@@ -24,56 +24,29 @@ struct kvm_ptp_clock {
DEFINE_SPINLOCK(kvm_ptp_lock);
-static struct pvclock_vsyscall_time_info *hv_clock;
-
-static struct kvm_clock_pairing clock_pair;
-static phys_addr_t clock_pair_gpa;
-
static int ptp_kvm_get_time_fn(ktime_t *device_time,
struct system_counterval_t *system_counter,
void *ctx)
{
- unsigned long ret;
+ unsigned long ret, cycle;
struct timespec64 tspec;
- unsigned version;
- int cpu;
- struct pvclock_vcpu_time_info *src;
+ struct clocksource *cs;
spin_lock(&kvm_ptp_lock);
preempt_disable_notrace();
- cpu = smp_processor_id();
- src = &hv_clock[cpu].pvti;
-
- do {
- /*
- * We are using a TSC value read in the hosts
- * kvm_hc_clock_pairing handling.
- * So any changes to tsc_to_system_mul
- * and tsc_shift or any other pvclock
- * data invalidate that measurement.
- */
- version = pvclock_read_begin(src);
-
- ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,
- clock_pair_gpa,
- KVM_CLOCK_PAIRING_WALLCLOCK);
- if (ret != 0) {
- pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret);
- spin_unlock(&kvm_ptp_lock);
- preempt_enable_notrace();
- return -EOPNOTSUPP;
- }
-
- tspec.tv_sec = clock_pair.sec;
- tspec.tv_nsec = clock_pair.nsec;
- ret = __pvclock_read_cycles(src, clock_pair.tsc);
- } while (pvclock_read_retry(src, version));
+ ret = kvm_arch_ptp_get_crosststamp(&cycle, &tspec, &cs);
+ if (ret != 0) {
+ pr_err_ratelimited("clock pairing hypercall ret %lu\n", ret);
+ spin_unlock(&kvm_ptp_lock);
+ preempt_enable_notrace();
+ return -EOPNOTSUPP;
+ }
preempt_enable_notrace();
- system_counter->cycles = ret;
- system_counter->cs = &kvm_clock;
+ system_counter->cycles = cycle;
+ system_counter->cs = cs;
*device_time = timespec64_to_ktime(tspec);
@@ -116,17 +89,13 @@ static int ptp_kvm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
spin_lock(&kvm_ptp_lock);
- ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,
- clock_pair_gpa,
- KVM_CLOCK_PAIRING_WALLCLOCK);
+ ret = kvm_arch_ptp_get_clock(&tspec);
if (ret != 0) {
pr_err_ratelimited("clock offset hypercall ret %lu\n", ret);
spin_unlock(&kvm_ptp_lock);
return -EOPNOTSUPP;
}
- tspec.tv_sec = clock_pair.sec;
- tspec.tv_nsec = clock_pair.nsec;
spin_unlock(&kvm_ptp_lock);
memcpy(ts, &tspec, sizeof(struct timespec64));
@@ -166,21 +135,11 @@ static void __exit ptp_kvm_exit(void)
static int __init ptp_kvm_init(void)
{
- long ret;
-
- if (!kvm_para_available())
- return -ENODEV;
-
- clock_pair_gpa = slow_virt_to_phys(&clock_pair);
- hv_clock = pvclock_get_pvti_cpu0_va();
+ int ret;
- if (!hv_clock)
- return -ENODEV;
-
- ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa,
- KVM_CLOCK_PAIRING_WALLCLOCK);
- if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP)
- return -ENODEV;
+ ret = kvm_arch_ptp_init();
+ if (ret)
+ return -EOPNOTSUPP;
kvm_ptp_clock.caps = ptp_kvm_caps;
diff --git a/drivers/ptp/ptp_kvm_x86.c b/drivers/ptp/ptp_kvm_x86.c
new file mode 100644
index 000000000000..6c891d7299c6
--- /dev/null
+++ b/drivers/ptp/ptp_kvm_x86.c
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Virtual PTP 1588 clock for use with KVM guests
+ *
+ * Copyright (C) 2017 Red Hat Inc.
+ */
+
+#include <asm/pvclock.h>
+#include <asm/kvmclock.h>
+#include <linux/module.h>
+#include <uapi/asm/kvm_para.h>
+#include <uapi/linux/kvm_para.h>
+#include <linux/ptp_clock_kernel.h>
+
+phys_addr_t clock_pair_gpa;
+struct kvm_clock_pairing clock_pair;
+struct pvclock_vsyscall_time_info *hv_clock;
+
+int kvm_arch_ptp_init(void)
+{
+ int ret;
+
+ if (!kvm_para_available())
+ return -ENODEV;
+
+ clock_pair_gpa = slow_virt_to_phys(&clock_pair);
+ hv_clock = pvclock_get_pvti_cpu0_va();
+ if (!hv_clock)
+ return -ENODEV;
+
+ ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING, clock_pair_gpa,
+ KVM_CLOCK_PAIRING_WALLCLOCK);
+ if (ret == -KVM_ENOSYS || ret == -KVM_EOPNOTSUPP)
+ return -ENODEV;
+
+ return 0;
+}
+
+int kvm_arch_ptp_get_clock(struct timespec64 *ts)
+{
+ long ret;
+
+ ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,
+ clock_pair_gpa,
+ KVM_CLOCK_PAIRING_WALLCLOCK);
+ if (ret != 0)
+ return -EOPNOTSUPP;
+
+ ts->tv_sec = clock_pair.sec;
+ ts->tv_nsec = clock_pair.nsec;
+
+ return 0;
+}
+
+int kvm_arch_ptp_get_crosststamp(unsigned long *cycle, struct timespec64 *tspec,
+ struct clocksource **cs)
+{
+ unsigned long ret;
+ unsigned int version;
+ int cpu;
+ struct pvclock_vcpu_time_info *src;
+
+ cpu = smp_processor_id();
+ src = &hv_clock[cpu].pvti;
+
+ do {
+ /*
+ * We are using a TSC value read in the hosts
+ * kvm_hc_clock_pairing handling.
+ * So any changes to tsc_to_system_mul
+ * and tsc_shift or any other pvclock
+ * data invalidate that measurement.
+ */
+ version = pvclock_read_begin(src);
+
+ ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,
+ clock_pair_gpa,
+ KVM_CLOCK_PAIRING_WALLCLOCK);
+ tspec->tv_sec = clock_pair.sec;
+ tspec->tv_nsec = clock_pair.nsec;
+ *cycle = __pvclock_read_cycles(src, clock_pair.tsc);
+ } while (pvclock_read_retry(src, version));
+
+ *cs = &kvm_clock;
+
+ return 0;
+}
diff --git a/include/asm-generic/ptp_kvm.h b/include/asm-generic/ptp_kvm.h
new file mode 100644
index 000000000000..e5dd386f6664
--- /dev/null
+++ b/include/asm-generic/ptp_kvm.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Virtual PTP 1588 clock for use with KVM guests
+ *
+ * Copyright (C) 2019 ARM Ltd.
+ * All Rights Reserved
+ */
+
+int kvm_arch_ptp_init(void);
+int kvm_arch_ptp_get_clock(struct timespec64 *ts);
+int kvm_arch_ptp_get_crosststamp(unsigned long *cycle,
+ struct timespec64 *tspec, void *cs);
--
2.17.1
From: Thomas Gleixner <[email protected]>
In some scenario like return device time to ptp_kvm guest,
we need identify the current clocksource outside core time code.
This patch add a mechanism to recognize the current clocksource
by export clocksource id in time_get_snapshot.
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Jianyong Wu <[email protected]>
---
include/linux/clocksource.h | 6 ++++++
include/linux/timekeeping.h | 12 +++++++-----
kernel/time/clocksource.c | 3 +++
kernel/time/timekeeping.c | 1 +
4 files changed, 17 insertions(+), 5 deletions(-)
diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index b21db536fd52..ac8016b22734 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -19,6 +19,7 @@
#include <linux/of.h>
#include <asm/div64.h>
#include <asm/io.h>
+#include <linux/clocksource_ids.h>
struct clocksource;
struct module;
@@ -49,6 +50,10 @@ struct module;
* 400-499: Perfect
* The ideal clocksource. A must-use where
* available.
+ * @id: Defaults to CSID_GENERIC. The id value is captured
+ * in certain snapshot functions to allow callers to
+ * validate the clocksource from which the snapshot was
+ * taken.
* @read: returns a cycle value, passes clocksource as argument
* @enable: optional function to enable the clocksource
* @disable: optional function to disable the clocksource
@@ -91,6 +96,7 @@ struct clocksource {
const char *name;
struct list_head list;
int rating;
+ enum clocksource_ids id;
int (*enable)(struct clocksource *cs);
void (*disable)(struct clocksource *cs);
unsigned long flags;
diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h
index a8ab0f143ac4..ecce56269a7e 100644
--- a/include/linux/timekeeping.h
+++ b/include/linux/timekeeping.h
@@ -2,6 +2,7 @@
#ifndef _LINUX_TIMEKEEPING_H
#define _LINUX_TIMEKEEPING_H
+#include <linux/clocksource_ids.h>
#include <linux/errno.h>
/* Included from linux/ktime.h */
@@ -204,11 +205,12 @@ extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta);
* @cs_was_changed_seq: The sequence number of clocksource change events
*/
struct system_time_snapshot {
- u64 cycles;
- ktime_t real;
- ktime_t raw;
- unsigned int clock_was_set_seq;
- u8 cs_was_changed_seq;
+ u64 cycles;
+ ktime_t real;
+ ktime_t raw;
+ enum clocksource_ids cs_id;
+ unsigned int clock_was_set_seq;
+ u8 cs_was_changed_seq;
};
/*
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index 3bcc19ceb073..26a3add61771 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -921,6 +921,9 @@ int __clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq)
clocksource_arch_init(cs);
+ if (WARN_ON_ONCE((unsigned int)cs->id >= CSID_MAX))
+ cs->id = CSID_GENERIC;
+
/* Initialize mult/shift and max_idle_ns */
__clocksource_update_freq_scale(cs, scale, freq);
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 44b726bab4bd..88078cff7fe2 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -974,6 +974,7 @@ void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot)
do {
seq = read_seqcount_begin(&tk_core.seq);
now = tk_clock_read(&tk->tkr_mono);
+ systime_snapshot->cs_id = tk->tkr_mono.clock->id;
systime_snapshot->cs_was_changed_seq = tk->cs_was_changed_seq;
systime_snapshot->clock_was_set_seq = tk->clock_was_set_seq;
base_real = ktime_add(tk->tkr_mono.base,
--
2.17.1
This patch is the base of ptp_kvm for arm64.
ptp_kvm modules will call hvc to get this service.
The service offers real time and counter cycle of host for guest.
Signed-off-by: Jianyong Wu <[email protected]>
---
drivers/clocksource/arm_arch_timer.c | 2 ++
include/clocksource/arm_arch_timer.h | 4 ++++
include/linux/arm-smccc.h | 12 ++++++++++++
virt/kvm/arm/psci.c | 22 ++++++++++++++++++++++
4 files changed, 40 insertions(+)
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 07e57a49d1e8..e4ad38042ef6 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -29,6 +29,7 @@
#include <asm/virt.h>
#include <clocksource/arm_arch_timer.h>
+#include <linux/clocksource_ids.h>
#define CNTTIDR 0x08
#define CNTTIDR_VIRT(n) (BIT(1) << ((n) * 4))
@@ -188,6 +189,7 @@ static u64 arch_counter_read_cc(const struct cyclecounter *cc)
static struct clocksource clocksource_counter = {
.name = "arch_sys_counter",
.rating = 400,
+ .id = CSID_ARM_ARCH_COUNTER,
.read = arch_counter_read,
.mask = CLOCKSOURCE_MASK(56),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index 1d68d5613dae..426d749e8cf8 100644
--- a/include/clocksource/arm_arch_timer.h
+++ b/include/clocksource/arm_arch_timer.h
@@ -104,6 +104,10 @@ static inline bool arch_timer_evtstrm_available(void)
return false;
}
+bool is_arm_arch_counter(void *unuse)
+{
+ return false;
+}
#endif
#endif
diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index 6f82c87308ed..aafb6bac167d 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -94,6 +94,7 @@
/* KVM "vendor specific" services */
#define ARM_SMCCC_KVM_FUNC_FEATURES 0
+#define ARM_SMCCC_KVM_PTP 1
#define ARM_SMCCC_KVM_FUNC_FEATURES_2 127
#define ARM_SMCCC_KVM_NUM_FUNCS 128
@@ -103,6 +104,17 @@
ARM_SMCCC_OWNER_VENDOR_HYP, \
ARM_SMCCC_KVM_FUNC_FEATURES)
+/*
+ * This ID used for virtual ptp kvm clock and it will pass second value
+ * and nanosecond value of host real time and system counter by vcpu
+ * register to guest.
+ */
+#define ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID \
+ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
+ ARM_SMCCC_SMC_32, \
+ ARM_SMCCC_OWNER_VENDOR_HYP, \
+ ARM_SMCCC_KVM_PTP)
+
#ifndef __ASSEMBLY__
#include <linux/linkage.h>
diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c
index 0debf49bf259..339bcbafac7b 100644
--- a/virt/kvm/arm/psci.c
+++ b/virt/kvm/arm/psci.c
@@ -15,6 +15,7 @@
#include <asm/kvm_host.h>
#include <kvm/arm_psci.h>
+#include <linux/clocksource_ids.h>
/*
* This is an implementation of the Power State Coordination Interface
@@ -392,6 +393,8 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
u32 func_id = smccc_get_function(vcpu);
u32 val[4] = {};
u32 option;
+ u64 cycles;
+ struct system_time_snapshot systime_snapshot;
val[0] = SMCCC_RET_NOT_SUPPORTED;
@@ -431,6 +434,25 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID:
val[0] = BIT(ARM_SMCCC_KVM_FUNC_FEATURES);
break;
+ /*
+ * This will used for virtual ptp kvm clock. three
+ * values will be passed back.
+ * reg0 stores high 32-bit host ktime;
+ * reg1 stores low 32-bit host ktime;
+ * reg2 stores high 32-bit difference of host cycles and cntvoff;
+ * reg3 stores low 32-bit difference of host cycles and cntvoff.
+ */
+ case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID:
+ ktime_get_snapshot(&systime_snapshot);
+ if (systime_snapshot.cs_id != CSID_ARM_ARCH_COUNTER)
+ return kvm_psci_call(vcpu);
+ val[0] = systime_snapshot.real >> 32;
+ val[1] = systime_snapshot.real << 32 >> 32;
+ cycles = systime_snapshot.cycles -
+ vcpu_vtimer(vcpu)->cntvoff;
+ val[2] = cycles >> 32;
+ val[3] = cycles << 32 >> 32;
+ break;
default:
return kvm_psci_call(vcpu);
}
--
2.17.1
Currently in arm64 virtualization environment, there is no mechanism to
keep time sync between guest and host. Time in guest will drift compared
with host after boot up as they may both use third party time sources
to correct their time respectively. The time deviation will be in order
of milliseconds but some scenarios ask for higher time precision, like
in cloud envirenment, we want all the VMs running in the host aquire the
same level accuracy from host clock.
Use of kvm ptp clock, which choose the host clock source clock as a
reference clock to sync time clock between guest and host has been adopted
by x86 which makes the time sync order from milliseconds to nanoseconds.
This patch enable kvm ptp on arm64 and we get the similar clock drift as
found with x86 with kvm ptp.
Test result comparison between with kvm ptp and without it in arm64 are
as follows. This test derived from the result of command 'chronyc
sources'. we should take more cure of the last sample column which shows
the offset between the local clock and the source at the last measurement.
no kvm ptp in guest:
MS Name/IP address Stratum Poll Reach LastRx Last sample
========================================================================
^* dns1.synet.edu.cn 2 6 377 13 +1040us[+1581us] +/- 21ms
^* dns1.synet.edu.cn 2 6 377 21 +1040us[+1581us] +/- 21ms
^* dns1.synet.edu.cn 2 6 377 29 +1040us[+1581us] +/- 21ms
^* dns1.synet.edu.cn 2 6 377 37 +1040us[+1581us] +/- 21ms
^* dns1.synet.edu.cn 2 6 377 45 +1040us[+1581us] +/- 21ms
^* dns1.synet.edu.cn 2 6 377 53 +1040us[+1581us] +/- 21ms
^* dns1.synet.edu.cn 2 6 377 61 +1040us[+1581us] +/- 21ms
^* dns1.synet.edu.cn 2 6 377 4 -130us[ +796us] +/- 21ms
^* dns1.synet.edu.cn 2 6 377 12 -130us[ +796us] +/- 21ms
^* dns1.synet.edu.cn 2 6 377 20 -130us[ +796us] +/- 21ms
in host:
MS Name/IP address Stratum Poll Reach LastRx Last sample
========================================================================
^* 120.25.115.20 2 7 377 72 -470us[ -603us] +/- 18ms
^* 120.25.115.20 2 7 377 92 -470us[ -603us] +/- 18ms
^* 120.25.115.20 2 7 377 112 -470us[ -603us] +/- 18ms
^* 120.25.115.20 2 7 377 2 +872ns[-6808ns] +/- 17ms
^* 120.25.115.20 2 7 377 22 +872ns[-6808ns] +/- 17ms
^* 120.25.115.20 2 7 377 43 +872ns[-6808ns] +/- 17ms
^* 120.25.115.20 2 7 377 63 +872ns[-6808ns] +/- 17ms
^* 120.25.115.20 2 7 377 83 +872ns[-6808ns] +/- 17ms
^* 120.25.115.20 2 7 377 103 +872ns[-6808ns] +/- 17ms
^* 120.25.115.20 2 7 377 123 +872ns[-6808ns] +/- 17ms
The dns1.synet.edu.cn is the network reference clock for guest and
120.25.115.20 is the network reference clock for host. we can't get the
clock error between guest and host directly, but a roughly estimated value
will be in order of hundreds of us to ms.
with kvm ptp in guest:
chrony has been disabled in host to remove the disturb by network clock.
MS Name/IP address Stratum Poll Reach LastRx Last sample
========================================================================
* PHC0 0 3 377 8 -7ns[ +1ns] +/- 3ns
* PHC0 0 3 377 8 +1ns[ +16ns] +/- 3ns
* PHC0 0 3 377 6 -4ns[ -0ns] +/- 6ns
* PHC0 0 3 377 6 -8ns[ -12ns] +/- 5ns
* PHC0 0 3 377 5 +2ns[ +4ns] +/- 4ns
* PHC0 0 3 377 13 +2ns[ +4ns] +/- 4ns
* PHC0 0 3 377 12 -4ns[ -6ns] +/- 4ns
* PHC0 0 3 377 11 -8ns[ -11ns] +/- 6ns
* PHC0 0 3 377 10 -14ns[ -20ns] +/- 4ns
* PHC0 0 3 377 8 +4ns[ +5ns] +/- 4ns
The PHC0 is the ptp clock which choose the host clock as its source
clock. So we can be sure to say that the clock error between host and guest
is in order of ns.
Signed-off-by: Jianyong Wu <[email protected]>
---
drivers/clocksource/arm_arch_timer.c | 22 ++++++++++++
drivers/ptp/Kconfig | 2 +-
drivers/ptp/ptp_kvm_arm64.c | 54 ++++++++++++++++++++++++++++
3 files changed, 77 insertions(+), 1 deletion(-)
create mode 100644 drivers/ptp/ptp_kvm_arm64.c
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index e4ad38042ef6..fe0ed8acfa33 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1636,3 +1636,25 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
}
TIMER_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init);
#endif
+
+#if IS_ENABLED(CONFIG_PTP_1588_CLOCK_KVM)
+#include <linux/arm-smccc.h>
+int kvm_arch_ptp_get_clock_fn(unsigned long *cycle, struct timespec64 *ts,
+ struct clocksource **cs)
+{
+ struct arm_smccc_res hvc_res;
+ ktime_t ktime_overall;
+
+ arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID, &hvc_res);
+ if ((long)(hvc_res.a0) < 0)
+ return -EOPNOTSUPP;
+
+ ktime_overall = hvc_res.a0 << 32 | hvc_res.a1;
+ *ts = ktime_to_timespec64(ktime_overall);
+ *cycle = hvc_res.a2 << 32 | hvc_res.a3;
+ *cs = &clocksource_counter;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(kvm_arch_ptp_get_clock_fn);
+#endif
diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig
index 9b8fee5178e8..3c31ff8eb05f 100644
--- a/drivers/ptp/Kconfig
+++ b/drivers/ptp/Kconfig
@@ -110,7 +110,7 @@ config PTP_1588_CLOCK_PCH
config PTP_1588_CLOCK_KVM
tristate "KVM virtual PTP clock"
depends on PTP_1588_CLOCK
- depends on KVM_GUEST && X86
+ depends on KVM_GUEST && X86 || ARM64 && ARM_ARCH_TIMER
default y
help
This driver adds support for using kvm infrastructure as a PTP
diff --git a/drivers/ptp/ptp_kvm_arm64.c b/drivers/ptp/ptp_kvm_arm64.c
new file mode 100644
index 000000000000..7c697f20904f
--- /dev/null
+++ b/drivers/ptp/ptp_kvm_arm64.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Virtual PTP 1588 clock for use with KVM guests
+ * Copyright (C) 2019 ARM Ltd.
+ * All Rights Reserved
+ */
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <asm/hypervisor.h>
+#include <linux/module.h>
+#include <linux/psci.h>
+#include <linux/arm-smccc.h>
+#include <linux/timecounter.h>
+#include <linux/sched/clock.h>
+#include <asm/arch_timer.h>
+
+int kvm_arch_ptp_init(void)
+{
+ struct arm_smccc_res hvc_res;
+
+ arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID,
+ &hvc_res);
+ if ((long)(hvc_res.a0) < 0)
+ return -EOPNOTSUPP;
+
+ return 0;
+}
+
+int kvm_arch_ptp_get_clock_generic(struct timespec64 *ts,
+ struct arm_smccc_res *hvc_res)
+{
+ u64 ns;
+ ktime_t ktime_overall;
+
+ arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID,
+ hvc_res);
+ if ((long)(hvc_res->a0) < 0)
+ return -EOPNOTSUPP;
+
+ ktime_overall = hvc_res->a0 << 32 | hvc_res->a1;
+ *ts = ktime_to_timespec64(ktime_overall);
+
+ return 0;
+}
+
+int kvm_arch_ptp_get_clock(struct timespec64 *ts)
+{
+ struct arm_smccc_res hvc_res;
+
+ kvm_arch_ptp_get_clock_generic(ts, &hvc_res);
+
+ return 0;
+}
--
2.17.1
Let userspace check if there is kvm ptp service in host.
before VMs migrate to a another host, VMM may check if this
cap is available to determine the migration behaviour.
Signed-off-by: Jianyong Wu <[email protected]>
Suggested-by: Marc Zyngier <[email protected]>
---
drivers/clocksource/arm_arch_timer.c | 4 ++--
drivers/ptp/ptp_kvm_arm64.c | 1 -
include/uapi/linux/kvm.h | 1 +
virt/kvm/arm/arm.c | 1 +
4 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index fe0ed8acfa33..0ae673193bee 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1639,7 +1639,7 @@ TIMER_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init);
#if IS_ENABLED(CONFIG_PTP_1588_CLOCK_KVM)
#include <linux/arm-smccc.h>
-int kvm_arch_ptp_get_clock_fn(unsigned long *cycle, struct timespec64 *ts,
+int kvm_arch_ptp_get_crosststamp(unsigned long *cycle, struct timespec64 *ts,
struct clocksource **cs)
{
struct arm_smccc_res hvc_res;
@@ -1656,5 +1656,5 @@ int kvm_arch_ptp_get_clock_fn(unsigned long *cycle, struct timespec64 *ts,
return 0;
}
-EXPORT_SYMBOL_GPL(kvm_arch_ptp_get_clock_fn);
+EXPORT_SYMBOL_GPL(kvm_arch_ptp_get_crosststamp);
#endif
diff --git a/drivers/ptp/ptp_kvm_arm64.c b/drivers/ptp/ptp_kvm_arm64.c
index 7c697f20904f..f3f957117865 100644
--- a/drivers/ptp/ptp_kvm_arm64.c
+++ b/drivers/ptp/ptp_kvm_arm64.c
@@ -30,7 +30,6 @@ int kvm_arch_ptp_init(void)
int kvm_arch_ptp_get_clock_generic(struct timespec64 *ts,
struct arm_smccc_res *hvc_res)
{
- u64 ns;
ktime_t ktime_overall;
arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID,
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 2fe12b40d503..a0bff6002bd9 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -993,6 +993,7 @@ struct kvm_ppc_resize_hpt {
#define KVM_CAP_ARM_SVE 170
#define KVM_CAP_ARM_PTRAUTH_ADDRESS 171
#define KVM_CAP_ARM_PTRAUTH_GENERIC 172
+#define KVM_CAP_ARM_KVM_PTP 173
#ifdef KVM_CAP_IRQ_ROUTING
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index bd5c55916d0d..80999985160b 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -201,6 +201,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
case KVM_CAP_MP_STATE:
case KVM_CAP_IMMEDIATE_EXIT:
case KVM_CAP_VCPU_EVENTS:
+ case KVM_CAP_ARM_KVM_PTP:
r = 1;
break;
case KVM_CAP_ARM_SET_DEVICE_ADDR:
--
2.17.1
Hi all,
Any comments?
Thanks
Jianyong
> -----Original Message-----
> From: Jianyong Wu <[email protected]>
> Sent: Thursday, October 24, 2019 7:02 PM
> To: [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; Mark Rutland
> <[email protected]>; [email protected]; Suzuki Poulose
> <[email protected]>
> Cc: [email protected]; [email protected];
> [email protected]; [email protected]; Steve Capper
> <[email protected]>; Kaly Xin (Arm Technology China)
> <[email protected]>; Justin He (Arm Technology China)
> <[email protected]>; Jianyong Wu (Arm Technology China)
> <[email protected]>; nd <[email protected]>
> Subject: [RFC PATCH v6 0/7] Enable ptp_kvm for arm64
>
> kvm ptp targets to provide high precision time sync between guest and host
> in virtualization environment. This patch enable kvm ptp for arm64.
> This patch set base on [1][2][3]
>
> change log:
> from v5 to v6:
> (1) apply Mark's patch[4] to get SMCCC conduit.
> (2) add mechanism to recognize current clocksource by add
> clocksouce_id value into struct clocksource instead of method in patch-v5.
> (3) rename kvm_arch_ptp_get_clock_fn into
> kvm_arch_ptp_get_crosststamp.
>
> from v4 to v5:
> (1) remove hvc delay compensasion as it should leave to userspace.
> (2) check current clocksource in hvc call service.
> (3) expose current clocksource by adding it to system_time_snapshot.
> (4) add helper to check if clocksource is arm_arch_counter.
> (5) rename kvm_ptp.c to ptp_kvm_common.c
>
> from v3 to v4:
> (1) fix clocksource of ptp_kvm to arch_sys_counter.
> (2) move kvm_arch_ptp_get_clock_fn into arm_arch_timer.c
> (3) subtract cntvoff before return cycles from host.
> (4) use ktime_get_snapshot instead of getnstimeofday and
> get_current_counterval to return time and counter value.
> (5) split ktime and counter into two 32-bit block respectively to avoid
> Y2038-safe issue.
> (6) set time compensation to device time as half of the delay of hvc call.
> (7) add ARM_ARCH_TIMER as dependency of ptp_kvm for arm64.
>
> from v2 to v3:
> (1) fix some issues in commit log.
> (2) add some receivers in send list.
>
> from v1 to v2:
> (1) move arch-specific code from arch/ to driver/ptp/
> (2) offer mechanism to inform userspace if ptp_kvm service is available.
> (3) separate ptp_kvm code for arm64 into hypervisor part and guest part.
> (4) add API to expose monotonic clock and counter value.
> (5) refine code: remove no necessary part and reconsitution.
>
> [1]https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/
> commit/?h=kvm/hvc&id=125ea89e4a21e2fc5235410f966a996a1a7148bf
> [2]https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/
> commit/?h=kvm/hvc&id=464f5a1741e5959c3e4d2be1966ae0093b4dce06
> [3]https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git/
> commit/?h=kvm/hvc&id=6597490e005d0eeca8ed8c1c1d7b4318ee014681
> [4]https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/
> commit/?h=for-next/smccc-conduit-
> cleanup&id=6b7fe77c334ae59fed9500140e08f4f896b36871
>
> Jianyong Wu (6):
> psci: let arm_smccc_1_1_invoke available by modules
> ptp: Reorganize ptp_kvm modules to make it arch-independent.
> time: Add mechanism to recognize clocksource in time_get_snapshot
> psci: Add hvc call service for ptp_kvm.
> ptp: arm64: Enable ptp_kvm for arm64
> kvm: arm64: Add capability check extension for ptp_kvm
>
> Mark Rutland (1):
> arm/arm64: smccc/psci: add arm_smccc_1_1_get_conduit()
>
> drivers/clocksource/arm_arch_timer.c | 24 ++++++
> drivers/firmware/psci/psci.c | 16 ++++
> drivers/ptp/Kconfig | 2 +-
> drivers/ptp/Makefile | 1 +
> drivers/ptp/ptp_kvm_arm64.c | 53 +++++++++++++
> drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} | 77 +++++-------------
> drivers/ptp/ptp_kvm_x86.c | 87 +++++++++++++++++++++
> include/asm-generic/ptp_kvm.h | 12 +++
> include/clocksource/arm_arch_timer.h | 4 +
> include/linux/arm-smccc.h | 30 ++++++-
> include/linux/clocksource.h | 6 ++
> include/linux/timekeeping.h | 12 +--
> include/uapi/linux/kvm.h | 1 +
> kernel/time/clocksource.c | 3 +
> kernel/time/timekeeping.c | 1 +
> virt/kvm/arm/arm.c | 1 +
> virt/kvm/arm/psci.c | 22 ++++++
> 17 files changed, 286 insertions(+), 66 deletions(-) create mode 100644
> drivers/ptp/ptp_kvm_arm64.c rename drivers/ptp/{ptp_kvm.c =>
> ptp_kvm_common.c} (63%) create mode 100644
> drivers/ptp/ptp_kvm_x86.c create mode 100644 include/asm-
> generic/ptp_kvm.h
>
> --
> 2.17.1
On Thu, 24 Oct 2019, Jianyong Wu wrote:
> From: Thomas Gleixner <[email protected]>
>
> In some scenario like return device time to ptp_kvm guest,
> we need identify the current clocksource outside core time code.
>
> This patch add a mechanism to recognize the current clocksource
> by export clocksource id in time_get_snapshot.
Please check Documentation/process/submitting-patches.rst and search for
'This patch'.
> diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
> index b21db536fd52..ac8016b22734 100644
> --- a/include/linux/clocksource.h
> +++ b/include/linux/clocksource.h
> @@ -19,6 +19,7 @@
> #include <linux/of.h>
> #include <asm/div64.h>
> #include <asm/io.h>
> +#include <linux/clocksource_ids.h>
Please place that include to the other linux includes. You might notice
that there is ordering here.
But where is that include? It's not part of that series, so how is this
supposed to compile?
Thanks,
tglx
On Thu, 24 Oct 2019, Jianyong Wu wrote:
> This patch is the base of ptp_kvm for arm64.
This patch ...
> ptp_kvm modules will call hvc to get this service.
> The service offers real time and counter cycle of host for guest.
>
> Signed-off-by: Jianyong Wu <[email protected]>
> ---
> drivers/clocksource/arm_arch_timer.c | 2 ++
> include/clocksource/arm_arch_timer.h | 4 ++++
> include/linux/arm-smccc.h | 12 ++++++++++++
> virt/kvm/arm/psci.c | 22 ++++++++++++++++++++++
> 4 files changed, 40 insertions(+)
>
> diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
> index 07e57a49d1e8..e4ad38042ef6 100644
> --- a/drivers/clocksource/arm_arch_timer.c
> +++ b/drivers/clocksource/arm_arch_timer.c
> @@ -29,6 +29,7 @@
> #include <asm/virt.h>
>
> #include <clocksource/arm_arch_timer.h>
> +#include <linux/clocksource_ids.h>
Same ordering issue and lack of file.
> diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
> index 1d68d5613dae..426d749e8cf8 100644
> --- a/include/clocksource/arm_arch_timer.h
> +++ b/include/clocksource/arm_arch_timer.h
> @@ -104,6 +104,10 @@ static inline bool arch_timer_evtstrm_available(void)
> return false;
> }
>
> +bool is_arm_arch_counter(void *unuse)
A global function in a header file? You might want to make this static
inline. And while at it please s/unuse/unused/
> +{
> + return false;
> +}
> #endif
> #include <linux/linkage.h>
> diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c
> index 0debf49bf259..339bcbafac7b 100644
> --- a/virt/kvm/arm/psci.c
> +++ b/virt/kvm/arm/psci.c
> @@ -15,6 +15,7 @@
> #include <asm/kvm_host.h>
>
> #include <kvm/arm_psci.h>
> +#include <linux/clocksource_ids.h>
Sigh.
> /*
> * This is an implementation of the Power State Coordination Interface
> @@ -392,6 +393,8 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
> u32 func_id = smccc_get_function(vcpu);
> u32 val[4] = {};
> u32 option;
> + u64 cycles;
> + struct system_time_snapshot systime_snapshot;
Also here you might notice that the variables are not randomly ordered.
Thanks,
tglx
Hi tglx,
> -----Original Message-----
> From: Thomas Gleixner <[email protected]>
> Sent: Thursday, November 7, 2019 3:56 PM
> To: Jianyong Wu (Arm Technology China) <[email protected]>
> Cc: [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; Mark Rutland <[email protected]>;
> [email protected]; Suzuki Poulose <[email protected]>; linux-
> [email protected]; [email protected];
> [email protected]; [email protected]; Steve Capper
> <[email protected]>; Kaly Xin (Arm Technology China)
> <[email protected]>; Justin He (Arm Technology China)
> <[email protected]>; nd <[email protected]>
> Subject: Re: [RFC PATCH v6 4/7] time: Add mechanism to recognize
> clocksource in time_get_snapshot
>
> On Thu, 24 Oct 2019, Jianyong Wu wrote:
> > From: Thomas Gleixner <[email protected]>
> >
> > In some scenario like return device time to ptp_kvm guest, we need
> > identify the current clocksource outside core time code.
> >
> > This patch add a mechanism to recognize the current clocksource by
> > export clocksource id in time_get_snapshot.
>
> Please check Documentation/process/submitting-patches.rst and search for
> 'This patch'.
>
Yeah, the expression should be more impersonal.
> > diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
> > index b21db536fd52..ac8016b22734 100644
> > --- a/include/linux/clocksource.h
> > +++ b/include/linux/clocksource.h
> > @@ -19,6 +19,7 @@
> > #include <linux/of.h>
> > #include <asm/div64.h>
> > #include <asm/io.h>
> > +#include <linux/clocksource_ids.h>
>
> Please place that include to the other linux includes. You might notice that
> there is ordering here.
>
Ok,
> But where is that include? It's not part of that series, so how is this supposed
> to compile?
OMG! Sorry, I added this file when I prepared my patches but missed to include it into this patch! This must be avoid latter.
Thanks
Jianyong
>
> Thanks,
>
> tglx
Hi tglx,
> -----Original Message-----
> From: Thomas Gleixner <[email protected]>
> Sent: Thursday, November 7, 2019 4:01 PM
> To: Jianyong Wu (Arm Technology China) <[email protected]>
> Cc: [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; Mark Rutland <[email protected]>;
> [email protected]; Suzuki Poulose <[email protected]>; linux-
> [email protected]; [email protected];
> [email protected]; [email protected]; Steve Capper
> <[email protected]>; Kaly Xin (Arm Technology China)
> <[email protected]>; Justin He (Arm Technology China)
> <[email protected]>; nd <[email protected]>
> Subject: Re: [RFC PATCH v6 5/7] psci: Add hvc call service for ptp_kvm.
>
> On Thu, 24 Oct 2019, Jianyong Wu wrote:
>
> > This patch is the base of ptp_kvm for arm64.
>
> This patch ...
>
Yeah, avoid subjective expression.
> > ptp_kvm modules will call hvc to get this service.
> > The service offers real time and counter cycle of host for guest.
> >
> > Signed-off-by: Jianyong Wu <[email protected]>
> > ---
> > drivers/clocksource/arm_arch_timer.c | 2 ++
> > include/clocksource/arm_arch_timer.h | 4 ++++
> > include/linux/arm-smccc.h | 12 ++++++++++++
> > virt/kvm/arm/psci.c | 22 ++++++++++++++++++++++
> > 4 files changed, 40 insertions(+)
> >
> > diff --git a/drivers/clocksource/arm_arch_timer.c
> > b/drivers/clocksource/arm_arch_timer.c
> > index 07e57a49d1e8..e4ad38042ef6 100644
> > --- a/drivers/clocksource/arm_arch_timer.c
> > +++ b/drivers/clocksource/arm_arch_timer.c
> > @@ -29,6 +29,7 @@
> > #include <asm/virt.h>
> >
> > #include <clocksource/arm_arch_timer.h>
> > +#include <linux/clocksource_ids.h>
>
> Same ordering issue and lack of file.
>
OK,
> > diff --git a/include/clocksource/arm_arch_timer.h
> > b/include/clocksource/arm_arch_timer.h
> > index 1d68d5613dae..426d749e8cf8 100644
> > --- a/include/clocksource/arm_arch_timer.h
> > +++ b/include/clocksource/arm_arch_timer.h
> > @@ -104,6 +104,10 @@ static inline bool
> arch_timer_evtstrm_available(void)
> > return false;
> > }
> >
> > +bool is_arm_arch_counter(void *unuse)
>
> A global function in a header file? You might want to make this static inline.
> And while at it please s/unuse/unused/
>
Should remove this residue line from v5 in v6.
> > +{
> > + return false;
> > +}
> > #endif
> > #include <linux/linkage.h>
> > diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c index
> > 0debf49bf259..339bcbafac7b 100644
> > --- a/virt/kvm/arm/psci.c
> > +++ b/virt/kvm/arm/psci.c
> > @@ -15,6 +15,7 @@
> > #include <asm/kvm_host.h>
> >
> > #include <kvm/arm_psci.h>
> > +#include <linux/clocksource_ids.h>
>
> Sigh.
>
Yeah,
> > /*
> > * This is an implementation of the Power State Coordination
> > Interface @@ -392,6 +393,8 @@ int kvm_hvc_call_handler(struct
> kvm_vcpu *vcpu)
> > u32 func_id = smccc_get_function(vcpu);
> > u32 val[4] = {};
> > u32 option;
> > + u64 cycles;
> > + struct system_time_snapshot systime_snapshot;
>
> Also here you might notice that the variables are not randomly ordered.
>
Do you mean considering the alignment then put "struct system_time_snapshot systime_snapshot" as the top one and u64 cycles as the second?
Thanks
Jianyong
> Thanks,
>
> tglx