treewide: Remove system_counterval_t.cs, which is never read

The clocksource pointer in struct system_counterval_t is not evaluated any
more. Remove the code setting the member, and the member itself.

Signed-off-by: Peter Hilber <peter.hilber@opensynergy.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240201010453.2212371-8-peter.hilber@opensynergy.com

Author: peter-hilber-at-opensynergy-dot-com

arch/x86/kernel/tsc.c

@@ -53,7 +53,6 @@ static int __read_mostly tsc_force_recalibrate;
 static u32 art_to_tsc_numerator;
 static u32 art_to_tsc_denominator;
 static u64 art_to_tsc_offset;
-static struct clocksource *art_related_clocksource;
 static bool have_art;
 
 struct cyc2ns {
@@ -1313,7 +1312,6 @@ struct system_counterval_t convert_art_to_tsc(u64 art)
 	res += tmp + art_to_tsc_offset;
 
 	return (struct system_counterval_t) {
-		.cs	= art_related_clocksource,
 		.cs_id	= have_art ? CSID_X86_TSC : CSID_GENERIC,
 		.cycles	= res,
 	};
@@ -1337,9 +1335,6 @@ EXPORT_SYMBOL(convert_art_to_tsc);
  *	corresponding clocksource:
  *	cycles:		System counter value
  *	cs_id:		The clocksource ID for validating comparability
- *	cs:		Clocksource corresponding to system counter value. Used
- *			by timekeeping code to verify comparability of two cycle
- *			values.
  */
 
 struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns)
@@ -1355,7 +1350,6 @@ struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns)
 	res += tmp;
 
 	return (struct system_counterval_t) {
-		.cs	= art_related_clocksource,
 		.cs_id	= have_art ? CSID_X86_TSC : CSID_GENERIC,
 		.cycles	= res,
 	};
@@ -1464,10 +1458,8 @@ static void tsc_refine_calibration_work(struct work_struct *work)
 	if (tsc_unstable)
 		goto unreg;
 
-	if (boot_cpu_has(X86_FEATURE_ART)) {
-		art_related_clocksource = &clocksource_tsc;
+	if (boot_cpu_has(X86_FEATURE_ART))
 		have_art = true;
-	}
 	clocksource_register_khz(&clocksource_tsc, tsc_khz);
 unreg:
 	clocksource_unregister(&clocksource_tsc_early);
@@ -1492,10 +1484,8 @@ static int __init init_tsc_clocksource(void)
 	 * the refined calibration and directly register it as a clocksource.
 	 */
 	if (boot_cpu_has(X86_FEATURE_TSC_KNOWN_FREQ)) {
-		if (boot_cpu_has(X86_FEATURE_ART)) {
-			art_related_clocksource = &clocksource_tsc;
+		if (boot_cpu_has(X86_FEATURE_ART))
 			have_art = true;
-		}
 		clocksource_register_khz(&clocksource_tsc, tsc_khz);
 		clocksource_unregister(&clocksource_tsc_early);
 

drivers/clocksource/arm_arch_timer.c

@@ -1807,7 +1807,6 @@ 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,
 				 enum clocksource_ids *cs_id)
 {
 	struct arm_smccc_res hvc_res;
@@ -1832,8 +1831,6 @@ int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *ts,
 	*ts = ktime_to_timespec64(ktime);
 	if (cycle)
 		*cycle = (u64)hvc_res.a2 << 32 | hvc_res.a3;
-	if (cs)
-		*cs = &clocksource_counter;
 	if (cs_id)
 		*cs_id = CSID_ARM_ARCH_COUNTER;
 

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, NULL);
+	return kvm_arch_ptp_get_crosststamp(NULL, ts, NULL);
 }

drivers/ptp/ptp_kvm_common.c

@@ -30,14 +30,13 @@ static int ptp_kvm_get_time_fn(ktime_t *device_time,
 {
 	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, &cs_id);
+	ret = kvm_arch_ptp_get_crosststamp(&cycle, &tspec, &cs_id);
 	if (ret) {
 		spin_unlock(&kvm_ptp_lock);
 		preempt_enable_notrace();
@@ -47,7 +46,6 @@ static int ptp_kvm_get_time_fn(ktime_t *device_time,
 	preempt_enable_notrace();
 
 	system_counter->cycles = cycle;
-	system_counter->cs = cs;
 	system_counter->cs_id = cs_id;
 
 	*device_time = timespec64_to_ktime(tspec);

drivers/ptp/ptp_kvm_x86.c

@@ -93,7 +93,6 @@ int kvm_arch_ptp_get_clock(struct timespec64 *ts)
 }
 
 int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *tspec,
-			      struct clocksource **cs,
 			      enum clocksource_ids *cs_id)
 {
 	struct pvclock_vcpu_time_info *src;
@@ -124,7 +123,6 @@ int kvm_arch_ptp_get_crosststamp(u64 *cycle, struct timespec64 *tspec,
 		*cycle = __pvclock_read_cycles(src, clock_pair->tsc);
 	} while (pvclock_read_retry(src, version));
 
-	*cs = &kvm_clock;
 	*cs_id = CSID_X86_KVM_CLK;
 
 	return 0;

include/linux/ptp_kvm.h

@@ -12,13 +12,11 @@
 #include <linux/types.h>
 
 struct timespec64;
-struct clocksource;
 
 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,
-		enum clocksource_ids *cs_id);
+		struct timespec64 *tspec, enum clocksource_ids *cs_id);
 
 #endif /* _PTP_KVM_H_ */

include/linux/timekeeping.h

@@ -271,16 +271,13 @@ struct system_device_crosststamp {
  * struct system_counterval_t - system counter value with the ID of the
  *				corresponding clocksource
  * @cycles:	System counter value
- * @cs:		Clocksource corresponding to system counter value. Timekeeping
- *		code now evaluates cs_id instead.
  * @cs_id:	Clocksource ID corresponding to system counter value. Used by
  *		timekeeping code to verify comparability of two cycle values.
  *		The default ID, CSID_GENERIC, does not identify a specific
  *		clocksource.
  */
 struct system_counterval_t {
 	u64			cycles;
-	struct clocksource	*cs;
 	enum clocksource_ids	cs_id;
 };