Re: [PATCH v16 3/9] ptp: Reorganize ptp_kvm module to make it arch-independent.

2021-02-02 Thread Marc Zyngier 

On 2020-12-09 06:09, Jianyong Wu wrote:
Currently, ptp_kvm modules implementation is only for x86 which 
includes

large part of arch-specific code.  This patch moves all of this code
into a new arch related file in the same directory.

Signed-off-by: Jianyong Wu 
---
 drivers/ptp/Makefile|  1 +
 drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} | 84 +-
 drivers/ptp/ptp_kvm_x86.c   | 96 +
 include/linux/ptp_kvm.h | 16 
 4 files changed, 135 insertions(+), 62 deletions(-)
 rename drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} (60%)
 create mode 100644 drivers/ptp/ptp_kvm_x86.c
 create mode 100644 include/linux/ptp_kvm.h



[...]


diff --git a/include/linux/ptp_kvm.h b/include/linux/ptp_kvm.h
new file mode 100644
index ..6f104b1967bb
--- /dev/null
+++ b/include/linux/ptp_kvm.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Virtual PTP 1588 clock for use with KVM guests
+ *
+ * Copyright (C) 2017 Red Hat Inc.
+ */
+
+#ifndef _PTP_KVM_H_
+#define _PTP_KVM_H_
+
+int kvm_arch_ptp_init(void);
+int kvm_arch_ptp_get_clock(struct timespec64 *ts);
+int kvm_arch_ptp_get_crosststamp(u64 *cycle,
+   struct timespec64 *tspec, struct clocksource **cs);


You probably want some forward declarations for timespec64 and
clocksource, so that this include file is standalone.

Thanks,

M.
--
Jazz is not dead. It just smells funny...

[PATCH v16 3/9] ptp: Reorganize ptp_kvm module to make it arch-independent.

2020-12-08 Thread Jianyong Wu 
Currently, ptp_kvm modules implementation is only for x86 which includes
large part of arch-specific code.  This patch moves all of this code
into a new arch related file in the same directory.

Signed-off-by: Jianyong Wu 
---
 drivers/ptp/Makefile|  1 +
 drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} | 84 +-
 drivers/ptp/ptp_kvm_x86.c   | 96 +
 include/linux/ptp_kvm.h | 16 
 4 files changed, 135 insertions(+), 62 deletions(-)
 rename drivers/ptp/{ptp_kvm.c => ptp_kvm_common.c} (60%)
 create mode 100644 drivers/ptp/ptp_kvm_x86.c
 create mode 100644 include/linux/ptp_kvm.h

diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile
index 7aff75f745dc..699a4e4d19c2 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-$(CONFIG_X86)  := ptp_kvm_x86.o ptp_kvm_common.o
 obj-$(CONFIG_PTP_1588_CLOCK)   += ptp.o
 obj-$(CONFIG_PTP_1588_CLOCK_DTE)   += ptp_dte.o
 obj-$(CONFIG_PTP_1588_CLOCK_INES)  += ptp_ines.o
diff --git a/drivers/ptp/ptp_kvm.c b/drivers/ptp/ptp_kvm_common.c
similarity index 60%
rename from drivers/ptp/ptp_kvm.c
rename to drivers/ptp/ptp_kvm_common.c
index 658d33fc3195..721ddcede5e1 100644
--- a/drivers/ptp/ptp_kvm.c
+++ b/drivers/ptp/ptp_kvm_common.c
@@ -8,11 +8,11 @@
 #include 
 #include 
 #include 
+#include 
 #include 
+#include 
 #include 
 #include 
-#include 
-#include 
 #include 
 
 #include 
@@ -24,56 +24,29 @@ struct kvm_ptp_clock {
 
 static 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;
+   long ret;
+   u64 cycle;
struct timespec64 tspec;
-   unsigned version;
-   int cpu;
-   struct pvclock_vcpu_time_info *src;
+   struct clocksource *cs;
 
spin_lock(_ptp_lock);
 
preempt_disable_notrace();
-   cpu = smp_processor_id();
-   src = _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(_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(, , );
+   if (ret) {
+   spin_unlock(_ptp_lock);
+   preempt_enable_notrace();
+   return ret;
+   }
 
preempt_enable_notrace();
 
-   system_counter->cycles = ret;
-   system_counter->cs = _clock;
+   system_counter->cycles = cycle;
+   system_counter->cs = cs;
 
*device_time = timespec64_to_ktime(tspec);
 
@@ -111,22 +84,17 @@ static int ptp_kvm_settime(struct ptp_clock_info *ptp,
 
 static int ptp_kvm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
 {
-   unsigned long ret;
+   long ret;
struct timespec64 tspec;
 
spin_lock(_ptp_lock);
 
-   ret = kvm_hypercall2(KVM_HC_CLOCK_PAIRING,
-clock_pair_gpa,
-KVM_CLOCK_PAIRING_WALLCLOCK);
-   if (ret != 0) {
-   pr_err_ratelimited("clock offset hypercall ret %lu\n", ret);
+   ret = kvm_arch_ptp_get_clock();
+   if (ret) {
spin_unlock(_ptp_lock);
-   return -EOPNOTSUPP;
+   return ret;
}
 
-   tspec.tv_sec = clock_pair.sec;
-   tspec.tv_nsec = clock_pair.nsec;
spin_unlock(_ptp_lock);
 
memcpy(ts, , sizeof(struct timespec64));
@@ -168,19 +136,11 @@ static int __init ptp_kvm_init(void)
 {
long ret;
 
-   if (!kvm_para_available())
-   return -ENODEV;
-
-   clock_pair_gpa = slow_virt_to_phys(_pair);
-   hv_clock = pvclock_get_pvti_cpu0_va();
-
-   if (!hv_clock)
-   return -ENODEV;
-
-   ret =