From: Changwoo Min Date: Thu, 9 Jan 2025 13:14:56 +0000 (+0900) Subject: sched_ext: Use time helpers in BPF schedulers X-Git-Tag: v6.14-rc1~121^2~1 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=62addc6dbf3644272c064c16076221bf4f633f25;p=linux-2.6-block.git sched_ext: Use time helpers in BPF schedulers Modify the BPF schedulers to use time helpers defined in common.bpf.h Signed-off-by: Changwoo Min Acked-by: Andrea Righi Signed-off-by: Tejun Heo --- diff --git a/tools/sched_ext/scx_central.bpf.c b/tools/sched_ext/scx_central.bpf.c index 4239034ad593..50bc1737c167 100644 --- a/tools/sched_ext/scx_central.bpf.c +++ b/tools/sched_ext/scx_central.bpf.c @@ -87,11 +87,6 @@ struct { __type(value, struct central_timer); } central_timer SEC(".maps"); -static bool vtime_before(u64 a, u64 b) -{ - return (s64)(a - b) < 0; -} - s32 BPF_STRUCT_OPS(central_select_cpu, struct task_struct *p, s32 prev_cpu, u64 wake_flags) { @@ -279,7 +274,7 @@ static int central_timerfn(void *map, int *key, struct bpf_timer *timer) /* kick iff the current one exhausted its slice */ started_at = ARRAY_ELEM_PTR(cpu_started_at, cpu, nr_cpu_ids); if (started_at && *started_at && - vtime_before(now, *started_at + slice_ns)) + time_before(now, *started_at + slice_ns)) continue; /* and there's something pending */ diff --git a/tools/sched_ext/scx_flatcg.bpf.c b/tools/sched_ext/scx_flatcg.bpf.c index 5f588963fb2f..2c720e3ecad5 100644 --- a/tools/sched_ext/scx_flatcg.bpf.c +++ b/tools/sched_ext/scx_flatcg.bpf.c @@ -137,11 +137,6 @@ static u64 div_round_up(u64 dividend, u64 divisor) return (dividend + divisor - 1) / divisor; } -static bool vtime_before(u64 a, u64 b) -{ - return (s64)(a - b) < 0; -} - static bool cgv_node_less(struct bpf_rb_node *a, const struct bpf_rb_node *b) { struct cgv_node *cgc_a, *cgc_b; @@ -271,7 +266,7 @@ static void cgrp_cap_budget(struct cgv_node *cgv_node, struct fcg_cgrp_ctx *cgc) */ max_budget = (cgrp_slice_ns * nr_cpus * cgc->hweight) / (2 * FCG_HWEIGHT_ONE); - if (vtime_before(cvtime, cvtime_now - max_budget)) + if (time_before(cvtime, cvtime_now - max_budget)) cvtime = cvtime_now - max_budget; cgv_node->cvtime = cvtime; @@ -401,7 +396,7 @@ void BPF_STRUCT_OPS(fcg_enqueue, struct task_struct *p, u64 enq_flags) * Limit the amount of budget that an idling task can accumulate * to one slice. */ - if (vtime_before(tvtime, cgc->tvtime_now - SCX_SLICE_DFL)) + if (time_before(tvtime, cgc->tvtime_now - SCX_SLICE_DFL)) tvtime = cgc->tvtime_now - SCX_SLICE_DFL; scx_bpf_dsq_insert_vtime(p, cgrp->kn->id, SCX_SLICE_DFL, @@ -535,7 +530,7 @@ void BPF_STRUCT_OPS(fcg_running, struct task_struct *p) * from multiple CPUs and thus racy. Any error should be * contained and temporary. Let's just live with it. */ - if (vtime_before(cgc->tvtime_now, p->scx.dsq_vtime)) + if (time_before(cgc->tvtime_now, p->scx.dsq_vtime)) cgc->tvtime_now = p->scx.dsq_vtime; } bpf_cgroup_release(cgrp); @@ -645,7 +640,7 @@ static bool try_pick_next_cgroup(u64 *cgidp) cgv_node = container_of(rb_node, struct cgv_node, rb_node); cgid = cgv_node->cgid; - if (vtime_before(cvtime_now, cgv_node->cvtime)) + if (time_before(cvtime_now, cgv_node->cvtime)) cvtime_now = cgv_node->cvtime; /* @@ -744,7 +739,7 @@ void BPF_STRUCT_OPS(fcg_dispatch, s32 cpu, struct task_struct *prev) if (!cpuc->cur_cgid) goto pick_next_cgroup; - if (vtime_before(now, cpuc->cur_at + cgrp_slice_ns)) { + if (time_before(now, cpuc->cur_at + cgrp_slice_ns)) { if (scx_bpf_dsq_move_to_local(cpuc->cur_cgid)) { stat_inc(FCG_STAT_CNS_KEEP); return; @@ -920,14 +915,14 @@ void BPF_STRUCT_OPS(fcg_cgroup_move, struct task_struct *p, struct cgroup *from, struct cgroup *to) { struct fcg_cgrp_ctx *from_cgc, *to_cgc; - s64 vtime_delta; + s64 delta; /* find_cgrp_ctx() triggers scx_ops_error() on lookup failures */ if (!(from_cgc = find_cgrp_ctx(from)) || !(to_cgc = find_cgrp_ctx(to))) return; - vtime_delta = p->scx.dsq_vtime - from_cgc->tvtime_now; - p->scx.dsq_vtime = to_cgc->tvtime_now + vtime_delta; + delta = time_delta(p->scx.dsq_vtime, from_cgc->tvtime_now); + p->scx.dsq_vtime = to_cgc->tvtime_now + delta; } s32 BPF_STRUCT_OPS_SLEEPABLE(fcg_init) diff --git a/tools/sched_ext/scx_simple.bpf.c b/tools/sched_ext/scx_simple.bpf.c index 31f915b286c6..e6de99dba7db 100644 --- a/tools/sched_ext/scx_simple.bpf.c +++ b/tools/sched_ext/scx_simple.bpf.c @@ -52,11 +52,6 @@ static void stat_inc(u32 idx) (*cnt_p)++; } -static inline bool vtime_before(u64 a, u64 b) -{ - return (s64)(a - b) < 0; -} - s32 BPF_STRUCT_OPS(simple_select_cpu, struct task_struct *p, s32 prev_cpu, u64 wake_flags) { bool is_idle = false; @@ -84,7 +79,7 @@ void BPF_STRUCT_OPS(simple_enqueue, struct task_struct *p, u64 enq_flags) * Limit the amount of budget that an idling task can accumulate * to one slice. */ - if (vtime_before(vtime, vtime_now - SCX_SLICE_DFL)) + if (time_before(vtime, vtime_now - SCX_SLICE_DFL)) vtime = vtime_now - SCX_SLICE_DFL; scx_bpf_dsq_insert_vtime(p, SHARED_DSQ, SCX_SLICE_DFL, vtime, @@ -108,7 +103,7 @@ void BPF_STRUCT_OPS(simple_running, struct task_struct *p) * thus racy. Any error should be contained and temporary. Let's just * live with it. */ - if (vtime_before(vtime_now, p->scx.dsq_vtime)) + if (time_before(vtime_now, p->scx.dsq_vtime)) vtime_now = p->scx.dsq_vtime; }