mirrors/linux
2
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-05-16 10:11:38 -04:00
Code Issues Packages Projects Releases Wiki Activity

sched/fair: Simplify the entry condition for update_idle_cpu_scan()

Browse Source 
Only the topmost SD_SHARE_LLC domain has the "sd->shared" assigned.
Simply use "sd->shared" as an indicator for load balancing at the highest
SD_SHARE_LLC domain in update_idle_cpu_scan() instead of relying on
llc_size.

Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Chen Yu <yu.c.chen@intel.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://patch.msgid.link/20260312044434.1974-9-kprateek.nayak@amd.com
This commit is contained in:
K Prateek Nayak
2026-03-12 04:44:33 +00:00
committed by Peter Zijlstra
parent fa6874dfee
commit f1320a8dd8
1 changed files with 4 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
kernel/sched/fair.c
View File

@@ -11234,6 +11234,7 @@ static void update_idle_cpu_scan(struct lb_env *env,
unsigned long sum_util)
{
struct sched_domain_shared *sd_share;
struct sched_domain *sd = env->sd;
int llc_weight, pct;
u64 x, y, tmp;
/*
@@ -11247,11 +11248,7 @@ static void update_idle_cpu_scan(struct lb_env *env,
if (!sched_feat(SIS_UTIL) || env->idle == CPU_NEWLY_IDLE)
return;
llc_weight = per_cpu(sd_llc_size, env->dst_cpu);
if (env->sd->span_weight != llc_weight)
return;
sd_share = rcu_dereference_all(per_cpu(sd_llc_shared, env->dst_cpu));
sd_share = sd->shared;
if (!sd_share)
return;
@@ -11285,10 +11282,11 @@ static void update_idle_cpu_scan(struct lb_env *env,
*/
/* equation [3] */
x = sum_util;
llc_weight = sd->span_weight;
do_div(x, llc_weight);
/* equation [4] */
pct = env->sd->imbalance_pct;
pct = sd->imbalance_pct;
tmp = x * x * pct * pct;
do_div(tmp, 10000 * SCHED_CAPACITY_SCALE);
tmp = min_t(long, tmp, SCHED_CAPACITY_SCALE);