[tip: timers/vdso] x86/vdso: Prepare introduction of struct vdso_clock

From: tip-bot2 for Anna-Maria Behnsen
Date: Sat Mar 08 2025 - 08:45:37 EST


The following commit has been merged into the timers/vdso branch of tip:

Commit-ID: bf0eff816e467f8decb9b3ac0218cc26060e359f
Gitweb: https://git.kernel.org/tip/bf0eff816e467f8decb9b3ac0218cc26060e359f
Author: Anna-Maria Behnsen <anna-maria@xxxxxxxxxxxxx>
AuthorDate: Mon, 03 Mar 2025 12:11:17 +01:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Sat, 08 Mar 2025 14:37:41 +01:00

x86/vdso: Prepare introduction of struct vdso_clock

To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be array of VDSO clocks. At the moment,
vdso_clock is simply a define which maps vdso_clock to vdso_time_data.

To prepare for the rework of the data structures, replace the struct
vdso_time_data pointer with a struct vdso_clock pointer where applicable.

No functional change.

Signed-off-by: Anna-Maria Behnsen <anna-maria@xxxxxxxxxxxxx>
Signed-off-by: Nam Cao <namcao@xxxxxxxxxxxxx>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/all/20250303-vdso-clock-v1-15-c1b5c69a166f@xxxxxxxxxxxxx

---
arch/x86/include/asm/vdso/gettimeofday.h | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/vdso/gettimeofday.h b/arch/x86/include/asm/vdso/gettimeofday.h
index edec796..9e52cc4 100644
--- a/arch/x86/include/asm/vdso/gettimeofday.h
+++ b/arch/x86/include/asm/vdso/gettimeofday.h
@@ -261,7 +261,7 @@ static inline u64 __arch_get_hw_counter(s32 clock_mode,
return U64_MAX;
}

-static inline bool arch_vdso_clocksource_ok(const struct vdso_time_data *vd)
+static inline bool arch_vdso_clocksource_ok(const struct vdso_clock *vc)
{
return true;
}
@@ -300,34 +300,34 @@ static inline bool arch_vdso_cycles_ok(u64 cycles)
* declares everything with the MSB/Sign-bit set as invalid. Therefore the
* effective mask is S64_MAX.
*/
-static __always_inline u64 vdso_calc_ns(const struct vdso_time_data *vd, u64 cycles, u64 base)
+static __always_inline u64 vdso_calc_ns(const struct vdso_clock *vc, u64 cycles, u64 base)
{
- u64 delta = cycles - vd->cycle_last;
+ u64 delta = cycles - vc->cycle_last;

/*
* Negative motion and deltas which can cause multiplication
* overflow require special treatment. This check covers both as
- * negative motion is guaranteed to be greater than @vd::max_cycles
+ * negative motion is guaranteed to be greater than @vc::max_cycles
* due to unsigned comparison.
*
* Due to the MSB/Sign-bit being used as invalid marker (see
* arch_vdso_cycles_ok() above), the effective mask is S64_MAX, but that
* case is also unlikely and will also take the unlikely path here.
*/
- if (unlikely(delta > vd->max_cycles)) {
+ if (unlikely(delta > vc->max_cycles)) {
/*
* Due to the above mentioned TSC wobbles, filter out
* negative motion. Per the above masking, the effective
* sign bit is now bit 62.
*/
if (delta & (1ULL << 62))
- return base >> vd->shift;
+ return base >> vc->shift;

/* Handle multiplication overflow gracefully */
- return mul_u64_u32_add_u64_shr(delta & S64_MAX, vd->mult, base, vd->shift);
+ return mul_u64_u32_add_u64_shr(delta & S64_MAX, vc->mult, base, vc->shift);
}

- return ((delta * vd->mult) + base) >> vd->shift;
+ return ((delta * vc->mult) + base) >> vc->shift;
}
#define vdso_calc_ns vdso_calc_ns