diff options
| author | Christian Loehle <christian.loehle@arm.com> | 2025-11-10 12:08:19 +0000 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2025-11-12 21:02:07 +0100 |
| commit | 0796ddf4a7f0d15b0cf1ef6f265671f2e5174c1f (patch) | |
| tree | 94e7f28743fa3e60b5b2d46f21c7d49694be21d2 | |
| parent | 76934e495cdc31942b53b513cee4290750578a9a (diff) | |
cpuidle: teo: Use this_cpu_ptr() where possible
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>
| -rw-r--r-- | drivers/cpuidle/governors/teo.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/cpuidle/governors/teo.c b/drivers/cpuidle/governors/teo.c index bfa55c1eab5b..a3ebc2cda093 100644 --- a/drivers/cpuidle/governors/teo.c +++ b/drivers/cpuidle/governors/teo.c @@ -155,7 +155,7 @@ static DEFINE_PER_CPU(struct teo_cpu, teo_cpus); */ static void teo_update(struct cpuidle_driver *drv, struct cpuidle_device *dev) { - struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); + struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); int i, idx_timer = 0, idx_duration = 0; s64 target_residency_ns; u64 measured_ns; @@ -268,7 +268,7 @@ static int teo_find_shallower_state(struct cpuidle_driver *drv, static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, bool *stop_tick) { - struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); + struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); s64 latency_req = cpuidle_governor_latency_req(dev->cpu); ktime_t delta_tick = TICK_NSEC / 2; unsigned int idx_intercept_sum = 0; @@ -504,7 +504,7 @@ out_tick: */ static void teo_reflect(struct cpuidle_device *dev, int state) { - struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu); + struct teo_cpu *cpu_data = this_cpu_ptr(&teo_cpus); dev->last_state_idx = state; if (dev->poll_time_limit || |