ptp/kvm, arm_arch_timer: Set system_counterval_t.cs_id to constant

Identify the clocksources used by ptp_kvm by setting the clocksource ID
enum constants. This avoids dereferencing struct clocksource. Once the
system_counterval_t.cs member will be removed, this will also avoid the
need to obtain clocksource pointers from kvm_arch_ptp_get_crosststamp().

The clocksource IDs are associated to timestamps requested from the KVM
hypervisor, so the proper clocksource ID is known at the ptp_kvm request
site.

While at it, also make the ptp_kvm_get_time_fn() 'ret' variable type int as
that's what the function return value is.

Signed-off-by: Peter Hilber <peter.hilber@opensynergy.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240201010453.2212371-6-peter.hilber@opensynergy.com

diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index e054de92de91bceb06f7fd289d8c0c9c3b8c42f3..45a02872669e7380c9c2ec1c8c5da67158fba434 100644 (file)
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -1807,7 +1807,8 @@ TIMER_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init);
 #endif
 
 int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *ts,
-                                struct clocksource **cs)
+                                struct clocksource **cs,
+                                enum clocksource_ids *cs_id)
 {
        struct arm_smccc_res hvc_res;
        u32 ptp_counter;
@@ -1833,6 +1834,8 @@ int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *ts,
                *cycle = (u64)hvc_res.a2 << 32 | hvc_res.a3;
        if (cs)
                *cs = &clocksource_counter;
+       if (cs_id)
+               *cs_id = CSID_ARM_ARCH_COUNTER;
 
        return 0;
 }

diff --git a/drivers/ptp/ptp_kvm_arm.c b/drivers/ptp/ptp_kvm_arm.c
index e68e6943167beb448b0aca75665236ff8314773e..017bb5f03b14b6a630a4a253d1776e8d42174e1f 100644 (file)
--- a/drivers/ptp/ptp_kvm_arm.c
+++ b/drivers/ptp/ptp_kvm_arm.c
@@ -28,5 +28,5 @@ void kvm_arch_ptp_exit(void)
 
 int kvm_arch_ptp_get_clock(struct timespec64 *ts)
 {
-       return kvm_arch_ptp_get_crosststamp(NULL, ts, NULL);
+       return kvm_arch_ptp_get_crosststamp(NULL, ts, NULL, NULL);
 }

diff --git a/drivers/ptp/ptp_kvm_common.c b/drivers/ptp/ptp_kvm_common.c
index b0b36f135347cb6b10c96502c2f733c1afe4d252..f6683ba0ab3c23a07e41f405ba0dfedc67452dc0 100644 (file)
--- a/drivers/ptp/ptp_kvm_common.c
+++ b/drivers/ptp/ptp_kvm_common.c
@@ -4,7 +4,6 @@
  *
  * Copyright (C) 2017 Red Hat Inc.
  */
-#include <linux/clocksource.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/init.h>
@@ -29,15 +28,16 @@ static int ptp_kvm_get_time_fn(ktime_t *device_time,
                               struct system_counterval_t *system_counter,
                               void *ctx)
 {
-       long ret;
-       u64 cycle;
+       enum clocksource_ids cs_id;
        struct timespec64 tspec;
        struct clocksource *cs;
+       u64 cycle;
+       int ret;
 
        spin_lock(&kvm_ptp_lock);
 
        preempt_disable_notrace();
-       ret = kvm_arch_ptp_get_crosststamp(&cycle, &tspec, &cs);
+       ret = kvm_arch_ptp_get_crosststamp(&cycle, &tspec, &cs, &cs_id);
        if (ret) {
                spin_unlock(&kvm_ptp_lock);
                preempt_enable_notrace();
@@ -48,7 +48,7 @@ static int ptp_kvm_get_time_fn(ktime_t *device_time,
 
        system_counter->cycles = cycle;
        system_counter->cs = cs;
-       system_counter->cs_id = cs->id;
+       system_counter->cs_id = cs_id;
 
        *device_time = timespec64_to_ktime(tspec);
 

diff --git a/drivers/ptp/ptp_kvm_x86.c b/drivers/ptp/ptp_kvm_x86.c
index 902844cc1a17d5bd46461702ea149c852454db46..2782442922cb460075127d1d9e57778c8f3c3056 100644 (file)
--- a/drivers/ptp/ptp_kvm_x86.c
+++ b/drivers/ptp/ptp_kvm_x86.c
@@ -93,7 +93,8 @@ int kvm_arch_ptp_get_clock(struct timespec64 *ts)
 }
 
 int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *tspec,
-                             struct clocksource **cs)
+                             struct clocksource **cs,
+                             enum clocksource_ids *cs_id)
 {
        struct pvclock_vcpu_time_info *src;
        unsigned int version;
@@ -124,6 +125,7 @@ int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *tspec,
        } while (pvclock_read_retry(src, version));
 
        *cs = &kvm_clock;
+       *cs_id = CSID_X86_KVM_CLK;
 
        return 0;
 }

diff --git a/include/linux/ptp_kvm.h b/include/linux/ptp_kvm.h
index 746fd67c34806b0c19959b182a4088f5c560ceb8..95b3d4d0d7ddd0acb7f3133cf8cc8c38450ed7cd 100644 (file)
--- a/include/linux/ptp_kvm.h
+++ b/include/linux/ptp_kvm.h
@@ -8,6 +8,7 @@
 #ifndef _PTP_KVM_H_
 #define _PTP_KVM_H_
 
+#include <linux/clocksource_ids.h>
 #include <linux/types.h>
 
 struct timespec64;
@@ -17,6 +18,7 @@ int kvm_arch_ptp_init(void);
 void kvm_arch_ptp_exit(void);
 int kvm_arch_ptp_get_clock(struct timespec64 *ts);
 int kvm_arch_ptp_get_crosststamp(u64 *cycle,
-               struct timespec64 *tspec, struct clocksource **cs);
+               struct timespec64 *tspec, struct clocksource **cs,
+               enum clocksource_ids *cs_id);
 
 #endif /* _PTP_KVM_H_ */