Merge pull request #239 from hodgesds/cpufreq_helpers

Add CPU frequency related helpers and extend scx_layered
sched-ext · Apr 24, 2024 · 9a9b4dd · 9a9b4dd
2 parents a8daf37 + 32e97bf
commit 9a9b4dd
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Showing 4 changed files with 27 additions and 2 deletions.
diff --git a/scheds/include/scx/common.bpf.h b/scheds/include/scx/common.bpf.h
@@ -98,6 +98,9 @@ bool scx_bpf_task_running(const struct task_struct *p) __ksym;
 s32 scx_bpf_task_cpu(const struct task_struct *p) __ksym;
 struct cgroup *scx_bpf_task_cgroup(struct task_struct *p) __ksym;
 u32 scx_bpf_reenqueue_local(void) __ksym;
+u32 scx_bpf_cpuperf_cap(s32 cpu) __ksym;
+u32 scx_bpf_cpuperf_cur(s32 cpu) __ksym;
+void scx_bpf_cpuperf_set(u32 cpu, u32 perf) __ksym;
 
 #define BPF_STRUCT_OPS(name, args...)						\
 SEC("struct_ops/"#name)								\

diff --git a/scheds/rust/scx_layered/src/bpf/intf.h b/scheds/rust/scx_layered/src/bpf/intf.h
@@ -109,6 +109,7 @@ struct layer {
 	unsigned int		refresh_cpus;
 	unsigned char		cpus[MAX_CPUS_U8];
 	unsigned int		nr_cpus;	// managed from BPF side
+	unsigned int		perf;
 };
 
 #endif /* __INTF_H */
diff --git a/scheds/rust/scx_layered/src/bpf/main.bpf.c b/scheds/rust/scx_layered/src/bpf/main.bpf.c
@@ -728,6 +728,7 @@ void BPF_STRUCT_OPS(layered_running, struct task_struct *p)
 	struct cpu_ctx *cctx;
 	struct task_ctx *tctx;
 	struct layer *layer;
+	u32 cpu;
 
 	if (!(cctx = lookup_cpu_ctx(-1)) || !(tctx = lookup_task_ctx(p)) ||
 	    !(layer = lookup_layer(tctx->layer)))
@@ -740,12 +741,14 @@ void BPF_STRUCT_OPS(layered_running, struct task_struct *p)
 	cctx->current_exclusive = layer->exclusive;
 	tctx->started_running_at = bpf_ktime_get_ns();
 
+	cpu = scx_bpf_task_cpu(p);
+
 	/*
 	 * If this CPU is transitioning from running an exclusive task to a
 	 * non-exclusive one, the sibling CPU has likely been idle. Wake it up.
 	 */
 	if (cctx->prev_exclusive && !cctx->current_exclusive) {
-		s32 sib = sibling_cpu(scx_bpf_task_cpu(p));
+		s32 sib = sibling_cpu(cpu);
 		struct cpu_ctx *sib_cctx;
 
 		/*
@@ -760,6 +763,9 @@ void BPF_STRUCT_OPS(layered_running, struct task_struct *p)
 		}
 	}
 
+	if (layer->perf > 0)
+		scx_bpf_cpuperf_set(cpu, layer->perf);
+
 	cctx->maybe_idle = false;
 }
 

diff --git a/scheds/rust/scx_layered/src/main.rs b/scheds/rust/scx_layered/src/main.rs
@@ -320,6 +320,8 @@ enum LayerKind {
         cpus_range: Option<(usize, usize)>,
         #[serde(default)]
         min_exec_us: u64,
+        #[serde(default)]
+        perf: u64,
     },
     Grouped {
         util_range: (f64, f64),
@@ -331,6 +333,8 @@ enum LayerKind {
         preempt: bool,
         #[serde(default)]
         exclusive: bool,
+        #[serde(default)]
+        perf: u64,
     },
     Open {
         #[serde(default)]
@@ -339,6 +343,8 @@ enum LayerKind {
         preempt: bool,
         #[serde(default)]
         exclusive: bool,
+        #[serde(default)]
+        perf: u64,
     },
 }
 
@@ -1286,23 +1292,29 @@ impl<'a> Scheduler<'a> {
             layer.nr_match_ors = spec.matches.len() as u32;
 
             match &spec.kind {
-                LayerKind::Confined { min_exec_us, .. } => layer.min_exec_ns = min_exec_us * 1000,
+                LayerKind::Confined { min_exec_us, perf, .. } => {
+                    layer.min_exec_ns = min_exec_us * 1000;
+                    layer.perf = u32::try_from(*perf)?;
+                }
                 LayerKind::Open {
                     min_exec_us,
                     preempt,
                     exclusive,
+                    perf,
                     ..
                 }
                 | LayerKind::Grouped {
                     min_exec_us,
                     preempt,
                     exclusive,
+                    perf,
                     ..
                 } => {
                     layer.open.write(true);
                     layer.min_exec_ns = min_exec_us * 1000;
                     layer.preempt.write(*preempt);
                     layer.exclusive.write(*exclusive);
+                    layer.perf = u32::try_from(*perf)?;
                 }
             }
         }
@@ -1769,6 +1781,7 @@ fn write_example_file(path: &str) -> Result<()> {
                     cpus_range: Some((0, 16)),
                     util_range: (0.8, 0.9),
                     min_exec_us: 1000,
+                    perf: 1024,
                 },
             },
             LayerSpec {
@@ -1782,6 +1795,7 @@ fn write_example_file(path: &str) -> Result<()> {
                     min_exec_us: 100,
                     preempt: true,
                     exclusive: true,
+                    perf: 1024,
                 },
             },
             LayerSpec {
@@ -1794,6 +1808,7 @@ fn write_example_file(path: &str) -> Result<()> {
                     min_exec_us: 200,
                     preempt: false,
                     exclusive: false,
+                    perf: 1024,
                 },
             },
         ],