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x86/vdso: Prepare introduction of struct vdso_clock

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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@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250303-vdso-clock-v1-15-c1b5c69a166f@linutronix.de
This commit is contained in:
Anna-Maria Behnsen
2025-03-03 12:11:17 +01:00
committed by Thomas Gleixner
parent 5911e16cad
commit bf0eff816e
1 changed files with 8 additions and 8 deletions
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16
arch/x86/include/asm/vdso/gettimeofday.h
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@@ -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