diff mbox series

[RFC,v8,3/8] ptp: Reorganize ptp_kvm modules to make it arch-independent.

Message ID 20191125104506.36850-4-jianyong.wu@arm.com (mailing list archive)
State New, archived
Headers show
Series Enable ptp_kvm for arm64 | expand

Commit Message

Jianyong Wu Nov. 25, 2019, 10:45 a.m. UTC 
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 <jianyong.wu@arm.com>
---
 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

Comments

Marc Zyngier Nov. 25, 2019, 3:47 p.m. UTC | #1 
On 2019-11-25 10:45, Jianyong Wu wrote:
> 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 <jianyong.wu@arm.com>
> ---
>  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/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.

I think you should live the original copyright assignment here.
This really isn't anything new.

> + *  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);

Why is this include file in asm-generic? This isn't a kernel-wide API.

I think it should be sitting in drivers/ptp, as it is only shared 
between
the generic and arch-specific stuff.

Thanks,

         M.
Jianyong Wu Nov. 26, 2019, 8:30 a.m. UTC | #2 
Hi Marc,

> -----Original Message-----
> From: Marc Zyngier <maz@kernel.org>
> Sent: Monday, November 25, 2019 11:48 PM
> To: Jianyong Wu (Arm Technology China) <Jianyong.Wu@arm.com>
> Cc: netdev@vger.kernel.org; yangbo.lu@nxp.com; john.stultz@linaro.org;
> tglx@linutronix.de; pbonzini@redhat.com; sean.j.christopherson@intel.com;
> richardcochran@gmail.com; Mark Rutland <Mark.Rutland@arm.com>;
> will@kernel.org; Suzuki Poulose <Suzuki.Poulose@arm.com>; linux-
> kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
> kvmarm@lists.cs.columbia.edu; kvm@vger.kernel.org; Steve Capper
> <Steve.Capper@arm.com>; Kaly Xin (Arm Technology China)
> <Kaly.Xin@arm.com>; Justin He (Arm Technology China)
> <Justin.He@arm.com>; nd <nd@arm.com>
> Subject: Re: [RFC PATCH v8 3/8] ptp: Reorganize ptp_kvm modules to make it
> arch-independent.
> 
> On 2019-11-25 10:45, Jianyong Wu wrote:
> > 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 <jianyong.wu@arm.com>
> > ---
> >  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/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.
> 
> I think you should live the original copyright assignment here.
> This really isn't anything new.
> 

Ok,

> > + *  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);
> 
> Why is this include file in asm-generic? This isn't a kernel-wide API.
> 
> I think it should be sitting in drivers/ptp, as it is only shared between the
> generic and arch-specific stuff.

Ok, all these APIs used under driver/ptp, so it's better to move that header file into it.

Thanks
Jianyong
> 
> Thanks,
> 
>          M.
> --
> Jazz is not dead. It just smells funny...
diff mbox series

Patch

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);