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cpuidle: teo: Use this_cpu_ptr() where possible

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The cpuidle governor callbacks for update, select and reflect
are always running on the actual idle entering/exiting CPU, so
use the more optimized this_cpu_ptr() to access the internal teo
data.

This brings down the latency-critical teo_reflect() from
static void teo_reflect(struct cpuidle_device *dev, int state)
{
ffffffc080ffcff0:	hint	#0x19
ffffffc080ffcff4:	stp	x29, x30, [sp, #-48]!
	struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu);
ffffffc080ffcff8:	adrp	x2, ffffffc0848c0000 <gicv5_global_data+0x28>
{
ffffffc080ffcffc:	add	x29, sp, #0x0
ffffffc080ffd000:	stp	x19, x20, [sp, #16]
ffffffc080ffd004:	orr	x20, xzr, x0
	struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu);
ffffffc080ffd008:	add	x0, x2, #0xc20
{
ffffffc080ffd00c:	stp	x21, x22, [sp, #32]
	struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu);
ffffffc080ffd010:	adrp	x19, ffffffc083eb5000 <cpu_devices+0x78>
ffffffc080ffd014:	add	x19, x19, #0xbb0
ffffffc080ffd018:	ldr	w3, [x20, #4]

	dev->last_state_idx = state;

to

static void teo_reflect(struct cpuidle_device *dev, int state)
{
ffffffc080ffd034:	hint	#0x19
ffffffc080ffd038:	stp	x29, x30, [sp, #-48]!
ffffffc080ffd03c:	add	x29, sp, #0x0
ffffffc080ffd040:	stp	x19, x20, [sp, #16]
ffffffc080ffd044:	orr	x20, xzr, x0
	struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus);
ffffffc080ffd048:	adrp	x19, ffffffc083eb5000 <cpu_devices+0x78>
{
ffffffc080ffd04c:	stp	x21, x22, [sp, #32]
	struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus);
ffffffc080ffd050:	add	x19, x19, #0xbb0

	dev->last_state_idx = state;

This saves us:
	adrp    x2, ffffffc0848c0000 <gicv5_global_data+0x28>
	add     x0, x2, #0xc20
	ldr     w3, [x20, #4]

Signed-off-by: Christian Loehle <christian.loehle@arm.com>
[ rjw: Subject tweak ]
Link: https://patch.msgid.link/20251110120819.714560-1-christian.loehle@arm.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Christian Loehle 2025-11-10 12:08:19 +00:00 • committed by Rafael J. Wysocki
commit 0796ddf4a7
1 changed files with 3 additions and 3 deletions
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