From 43e33f53e25687ca870248d1939cfade0164426c Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 13 Jun 2025 15:23:29 -1000 Subject: [PATCH] sched/core: Reorganize cgroup bandwidth control interface file reads - Update tg_get_cfs_*() to return u64 values. These are now used as the low level accessors to the fair's bandwidth configuration parameters. Translation to usecs takes place in these functions. - Add tg_bandwidth() which reads all three bandwidth parameters using tg_get_cfs_*(). - Reimplement cgroup interface read functions using tg_bandwidth(). Drop cfs from the function names. This is to prepare for adding bandwidth control support to sched_ext. tg_bandwidth() will be used as the muxing point similar to tg_weight(). No functional changes. Signed-off-by: Tejun Heo Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20250614012346.2358261-4-tj@kernel.org --- kernel/sched/core.c | 58 +++++++++++++++++++++++++++++++-------------- 1 file changed, 40 insertions(+), 18 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index dc9668a6592f9..8de93a3bfa276 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -9404,7 +9404,7 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota, return 0; } -static long tg_get_cfs_period(struct task_group *tg) +static u64 tg_get_cfs_period(struct task_group *tg) { u64 cfs_period_us; @@ -9414,12 +9414,12 @@ static long tg_get_cfs_period(struct task_group *tg) return cfs_period_us; } -static long tg_get_cfs_quota(struct task_group *tg) +static u64 tg_get_cfs_quota(struct task_group *tg) { u64 quota_us; if (tg->cfs_bandwidth.quota == RUNTIME_INF) - return -1; + return RUNTIME_INF; quota_us = tg->cfs_bandwidth.quota; do_div(quota_us, NSEC_PER_USEC); @@ -9427,7 +9427,7 @@ static long tg_get_cfs_quota(struct task_group *tg) return quota_us; } -static long tg_get_cfs_burst(struct task_group *tg) +static u64 tg_get_cfs_burst(struct task_group *tg) { u64 burst_us; @@ -9614,22 +9614,42 @@ static int cpu_cfs_local_stat_show(struct seq_file *sf, void *v) return 0; } -static u64 cpu_cfs_period_read_u64(struct cgroup_subsys_state *css, - struct cftype *cft) +static void tg_bandwidth(struct task_group *tg, + u64 *period_us_p, u64 *quota_us_p, u64 *burst_us_p) { - return tg_get_cfs_period(css_tg(css)); + if (period_us_p) + *period_us_p = tg_get_cfs_period(tg); + if (quota_us_p) + *quota_us_p = tg_get_cfs_quota(tg); + if (burst_us_p) + *burst_us_p = tg_get_cfs_burst(tg); } -static s64 cpu_cfs_quota_read_s64(struct cgroup_subsys_state *css, - struct cftype *cft) +static u64 cpu_period_read_u64(struct cgroup_subsys_state *css, + struct cftype *cft) { - return tg_get_cfs_quota(css_tg(css)); + u64 period_us; + + tg_bandwidth(css_tg(css), &period_us, NULL, NULL); + return period_us; } -static u64 cpu_cfs_burst_read_u64(struct cgroup_subsys_state *css, - struct cftype *cft) +static s64 cpu_quota_read_s64(struct cgroup_subsys_state *css, + struct cftype *cft) { - return tg_get_cfs_burst(css_tg(css)); + u64 quota_us; + + tg_bandwidth(css_tg(css), NULL, "a_us, NULL); + return quota_us; /* (s64)RUNTIME_INF becomes -1 */ +} + +static u64 cpu_burst_read_u64(struct cgroup_subsys_state *css, + struct cftype *cft) +{ + u64 burst_us; + + tg_bandwidth(css_tg(css), NULL, NULL, &burst_us); + return burst_us; } static int cpu_cfs_period_write_u64(struct cgroup_subsys_state *css, @@ -9712,17 +9732,17 @@ static struct cftype cpu_legacy_files[] = { #ifdef CONFIG_CFS_BANDWIDTH { .name = "cfs_period_us", - .read_u64 = cpu_cfs_period_read_u64, + .read_u64 = cpu_period_read_u64, .write_u64 = cpu_cfs_period_write_u64, }, { .name = "cfs_quota_us", - .read_s64 = cpu_cfs_quota_read_s64, + .read_s64 = cpu_quota_read_s64, .write_s64 = cpu_cfs_quota_write_s64, }, { .name = "cfs_burst_us", - .read_u64 = cpu_cfs_burst_read_u64, + .read_u64 = cpu_burst_read_u64, .write_u64 = cpu_cfs_burst_write_u64, }, { @@ -9944,8 +9964,10 @@ static int __maybe_unused cpu_period_quota_parse(char *buf, static int cpu_max_show(struct seq_file *sf, void *v) { struct task_group *tg = css_tg(seq_css(sf)); + u64 period_us, quota_us; - cpu_period_quota_print(sf, tg_get_cfs_period(tg), tg_get_cfs_quota(tg)); + tg_bandwidth(tg, &period_us, "a_us, NULL); + cpu_period_quota_print(sf, period_us, quota_us); return 0; } @@ -9996,7 +10018,7 @@ static struct cftype cpu_files[] = { { .name = "max.burst", .flags = CFTYPE_NOT_ON_ROOT, - .read_u64 = cpu_cfs_burst_read_u64, + .read_u64 = cpu_burst_read_u64, .write_u64 = cpu_cfs_burst_write_u64, }, #endif /* CONFIG_CFS_BANDWIDTH */ -- 2.47.2