tools/sched_ext: Sync from the scx repo (b6ebdc635acf450e9c2e71717500…

tools/sched_ext/include/scx/common.h

@@ -28,8 +28,11 @@ typedef int64_t s64;
 
 #define SCX_BUG(__fmt, ...)							\
 	do {									\
-		fprintf(stderr, "%s:%d [scx panic]: %s\n", __FILE__, __LINE__,	\
-			strerror(errno));					\
+		fprintf(stderr, "[SCX_BUG] %s:%d", __FILE__, __LINE__);		\
+		if (errno)							\
+			fprintf(stderr, " (%s)\n", strerror(errno));		\
+		else								\
+			fprintf(stderr, "\n");					\
 		fprintf(stderr, __fmt __VA_OPT__(,) __VA_ARGS__);		\
 		fprintf(stderr, "\n");						\
 										\

tools/sched_ext/include/scx/compat.bpf.h

@@ -15,83 +15,6 @@
 	__ret;									\
 })
 
-/*
- * %SCX_KICK_IDLE is a later addition. To support both before and after, use
- * %__COMPAT_SCX_KICK_IDLE which becomes 0 on kernels which don't support it.
- * Users can use %SCX_KICK_IDLE directly in the future.
- */
-#define __COMPAT_SCX_KICK_IDLE							\
-	__COMPAT_ENUM_OR_ZERO(enum scx_kick_flags, SCX_KICK_IDLE)
-
-/*
- * scx_switch_all() was replaced by %SCX_OPS_SWITCH_PARTIAL. See
- * %__COMPAT_SCX_OPS_SWITCH_PARTIAL in compat.h. This can be dropped in the
- * future.
- */
-void scx_bpf_switch_all(void) __ksym __weak;
-
-static inline void __COMPAT_scx_bpf_switch_all(void)
-{
-	if (!bpf_core_enum_value_exists(enum scx_ops_flags, SCX_OPS_SWITCH_PARTIAL))
-		scx_bpf_switch_all();
-}
-
-/*
- * scx_bpf_exit() is a new addition. Fall back to scx_bpf_error() if
- * unavailable. Users can use scx_bpf_exit() directly in the future.
- */
-#define __COMPAT_scx_bpf_exit(code, fmt, args...)				\
-({										\
-	if (bpf_ksym_exists(scx_bpf_exit_bstr))					\
-		scx_bpf_exit((code), fmt, ##args);				\
-	else									\
-		scx_bpf_error(fmt, ##args);					\
-})
-
-/*
- * scx_bpf_dump() is a new addition. Ignore if unavailable. Users can use
- * scx_bpf_dump() directly in the future.
- */
-#define __COMPAT_scx_bpf_dump(fmt, args...)					\
-({										\
-	if (bpf_ksym_exists(scx_bpf_dump_bstr))					\
-		scx_bpf_dump(fmt, ##args);					\
-})
-
-/*
- * scx_bpf_nr_cpu_ids(), scx_bpf_get_possible/online_cpumask() are new. No good
- * way to noop these kfuncs. Provide a test macro. Users can assume existence in
- * the future.
- */
-#define __COMPAT_HAS_CPUMASKS							\
-	bpf_ksym_exists(scx_bpf_nr_cpu_ids)
-
-/*
- * cpuperf is new. The followings become noop on older kernels. Callers can be
- * updated to call cpuperf kfuncs directly in the future.
- */
-static inline u32 __COMPAT_scx_bpf_cpuperf_cap(s32 cpu)
-{
-	if (bpf_ksym_exists(scx_bpf_cpuperf_cap))
-		return scx_bpf_cpuperf_cap(cpu);
-	else
-		return 1024;
-}
-
-static inline u32 __COMPAT_scx_bpf_cpuperf_cur(s32 cpu)
-{
-	if (bpf_ksym_exists(scx_bpf_cpuperf_cur))
-		return scx_bpf_cpuperf_cur(cpu);
-	else
-		return 1024;
-}
-
-static inline void __COMPAT_scx_bpf_cpuperf_set(s32 cpu, u32 perf)
-{
-	if (bpf_ksym_exists(scx_bpf_cpuperf_set))
-		return scx_bpf_cpuperf_set(cpu, perf);
-}
-
 /*
  * Iteration and scx_bpf_consume_task() are new. The following become noop on
  * older kernels. The users can switch to bpf_for_each(scx_dsq) and directly

tools/sched_ext/include/scx/compat.h

@@ -106,23 +106,9 @@ static inline bool __COMPAT_struct_has_field(const char *type, const char *field
 	return false;
 }
 
-/*
- * An ops flag, %SCX_OPS_SWITCH_PARTIAL, replaced scx_bpf_switch_all() which had
- * to be called from ops.init(). To support both before and after, use both
- * %__COMPAT_SCX_OPS_SWITCH_PARTIAL and %__COMPAT_scx_bpf_switch_all() defined
- * in compat.bpf.h. Users can switch to directly using %SCX_OPS_SWITCH_PARTIAL
- * in the future.
- */
-#define __COMPAT_SCX_OPS_SWITCH_PARTIAL						\
+#define SCX_OPS_SWITCH_PARTIAL							\
 	__COMPAT_ENUM_OR_ZERO("scx_ops_flags", "SCX_OPS_SWITCH_PARTIAL")
 
-/*
- * scx_bpf_nr_cpu_ids(), scx_bpf_get_possible/online_cpumask() are new. Users
- * will be able to assume existence in the future.
- */
-#define __COMPAT_HAS_CPUMASKS							\
-	__COMPAT_has_ksym("scx_bpf_nr_cpu_ids")
-
 /*
  * DSQ iterator is new. Users will be able to assume existence in the future.
  */
@@ -157,43 +143,23 @@ static inline long scx_hotplug_seq(void)
  * and attach it, backward compatibility is automatically maintained where
  * reasonable.
  *
- * - ops.tick(): Ignored on older kernels with a warning.
- * - ops.dump*(): Ignored on older kernels with a warning.
- * - ops.exit_dump_len: Cleared to zero on older kernels with a warning.
- * - ops.hotplug_seq: Ignored on older kernels.
+ * ec7e3b0463e1 ("implement-ops") in https://github.com/sched-ext/sched_ext is
+ * the current minimum required kernel version.
  */
 #define SCX_OPS_OPEN(__ops_name, __scx_name) ({					\
 	struct __scx_name *__skel;						\
 										\
+	SCX_BUG_ON(!__COMPAT_struct_has_field("sched_ext_ops", "dump"),		\
+		   "sched_ext_ops.dump() missing, kernel too old?");		\
+										\
 	__skel = __scx_name##__open();						\
 	SCX_BUG_ON(!__skel, "Could not open " #__scx_name);			\
-										\
-	if (__COMPAT_struct_has_field("sched_ext_ops", "hotplug_seq"))		\
-		__skel->struct_ops.__ops_name->hotplug_seq = scx_hotplug_seq();	\
+	__skel->struct_ops.__ops_name->hotplug_seq = scx_hotplug_seq();		\
 	__skel; 								\
 })
 
 #define SCX_OPS_LOAD(__skel, __ops_name, __scx_name, __uei_name) ({		\
 	UEI_SET_SIZE(__skel, __ops_name, __uei_name);				\
-	if (!__COMPAT_struct_has_field("sched_ext_ops", "exit_dump_len") &&	\
-	    (__skel)->struct_ops.__ops_name->exit_dump_len) {			\
-		fprintf(stderr, "WARNING: kernel doesn't support setting exit dump len\n"); \
-		(__skel)->struct_ops.__ops_name->exit_dump_len = 0;		\
-	}									\
-	if (!__COMPAT_struct_has_field("sched_ext_ops", "tick") &&		\
-	    (__skel)->struct_ops.__ops_name->tick) {				\
-		fprintf(stderr, "WARNING: kernel doesn't support ops.tick()\n"); \
-		(__skel)->struct_ops.__ops_name->tick = NULL;			\
-	}									\
-	if (!__COMPAT_struct_has_field("sched_ext_ops", "dump") &&		\
-	    ((__skel)->struct_ops.__ops_name->dump ||				\
-	     (__skel)->struct_ops.__ops_name->dump_cpu ||			\
-	     (__skel)->struct_ops.__ops_name->dump_task)) {			\
-		fprintf(stderr, "WARNING: kernel doesn't support ops.dump*()\n"); \
-		(__skel)->struct_ops.__ops_name->dump = NULL;			\
-		(__skel)->struct_ops.__ops_name->dump_cpu = NULL;		\
-		(__skel)->struct_ops.__ops_name->dump_task = NULL;		\
-	}									\
 	SCX_BUG_ON(__scx_name##__load((__skel)), "Failed to load skel");	\
 })
 

tools/sched_ext/scx_central.bpf.c

@@ -175,7 +175,7 @@ static bool dispatch_to_cpu(s32 cpu)
 		scx_bpf_dispatch(p, SCX_DSQ_LOCAL_ON | cpu, SCX_SLICE_INF, 0);
 
 		if (cpu != central_cpu)
-			scx_bpf_kick_cpu(cpu, __COMPAT_SCX_KICK_IDLE);
+			scx_bpf_kick_cpu(cpu, SCX_KICK_IDLE);
 
 		bpf_task_release(p);
 		return true;
@@ -305,7 +305,6 @@ int BPF_STRUCT_OPS_SLEEPABLE(central_init)
 	struct bpf_timer *timer;
 	int ret;
 
-	__COMPAT_scx_bpf_switch_all();
 	ret = scx_bpf_create_dsq(FALLBACK_DSQ_ID, -1);
 	if (ret)
 		return ret;

tools/sched_ext/scx_qmap.bpf.c

@@ -41,7 +41,6 @@ const volatile bool print_shared_dsq;
 const volatile char exp_prefix[17];
 const volatile s32 disallow_tgid;
 const volatile bool suppress_dump;
-const volatile bool switch_partial;
 
 u32 test_error_cnt;
 
@@ -222,7 +221,7 @@ void BPF_STRUCT_OPS(qmap_enqueue, struct task_struct *p, u64 enq_flags)
 		scx_bpf_dispatch(p, SHARED_DSQ, 0, enq_flags);
 		cpu = scx_bpf_pick_idle_cpu(p->cpus_ptr, 0);
 		if (cpu >= 0)
-			scx_bpf_kick_cpu(cpu, __COMPAT_SCX_KICK_IDLE);
+			scx_bpf_kick_cpu(cpu, SCX_KICK_IDLE);
 		return;
 	}
 
@@ -476,13 +475,13 @@ void BPF_STRUCT_OPS(qmap_dump, struct scx_dump_ctx *dctx)
 		if (!(fifo = bpf_map_lookup_elem(&queue_arr, &i)))
 			return;
 
-		__COMPAT_scx_bpf_dump("QMAP FIFO[%d]:", i);
+		scx_bpf_dump("QMAP FIFO[%d]:", i);
 		bpf_repeat(4096) {
 			if (bpf_map_pop_elem(fifo, &pid))
 				break;
-			__COMPAT_scx_bpf_dump(" %d", pid);
+			scx_bpf_dump(" %d", pid);
 		}
-		__COMPAT_scx_bpf_dump("\n");
+		scx_bpf_dump("\n");
 	}
 }
 
@@ -496,9 +495,9 @@ void BPF_STRUCT_OPS(qmap_dump_cpu, struct scx_dump_ctx *dctx, s32 cpu, bool idle
 	if (!(cpuc = bpf_map_lookup_percpu_elem(&cpu_ctx_stor, &zero, cpu)))
 		return;
 
-	__COMPAT_scx_bpf_dump("QMAP: dsp_idx=%llu dsp_cnt=%llu avg_weight=%u cpuperf_target=%u",
-			      cpuc->dsp_idx, cpuc->dsp_cnt, cpuc->avg_weight,
-			      cpuc->cpuperf_target);
+	scx_bpf_dump("QMAP: dsp_idx=%llu dsp_cnt=%llu avg_weight=%u cpuperf_target=%u",
+		     cpuc->dsp_idx, cpuc->dsp_cnt, cpuc->avg_weight,
+		     cpuc->cpuperf_target);
 }
 
 void BPF_STRUCT_OPS(qmap_dump_task, struct scx_dump_ctx *dctx, struct task_struct *p)
@@ -510,8 +509,8 @@ void BPF_STRUCT_OPS(qmap_dump_task, struct scx_dump_ctx *dctx, struct task_struc
 	if (!(taskc = bpf_task_storage_get(&task_ctx_stor, p, 0, 0)))
 		return;
 
-	__COMPAT_scx_bpf_dump("QMAP: force_local=%d core_sched_seq=%llu",
-			      taskc->force_local, taskc->core_sched_seq);
+	scx_bpf_dump("QMAP: force_local=%d core_sched_seq=%llu",
+		     taskc->force_local, taskc->core_sched_seq);
 }
 
 /*
@@ -525,9 +524,6 @@ static void print_cpus(void)
 	char buf[128] = "", *p;
 	int idx;
 
-	if (!__COMPAT_HAS_CPUMASKS)
-		return;
-
 	possible = scx_bpf_get_possible_cpumask();
 	online = scx_bpf_get_online_cpumask();
 
@@ -593,9 +589,6 @@ static void monitor_cpuperf(void)
 	const struct cpumask *online;
 	int i, nr_online_cpus = 0;
 
-	if (!__COMPAT_HAS_CPUMASKS)
-		return;
-
 	nr_cpu_ids = scx_bpf_nr_cpu_ids();
 	online = scx_bpf_get_online_cpumask();
 
@@ -683,9 +676,6 @@ s32 BPF_STRUCT_OPS_SLEEPABLE(qmap_init)
 	struct bpf_timer *timer;
 	s32 ret;
 
-	if (!switch_partial)
-		__COMPAT_scx_bpf_switch_all();
-
 	print_cpus();
 
 	ret = scx_bpf_create_dsq(SHARED_DSQ, -1);

tools/sched_ext/scx_qmap.c

@@ -104,8 +104,7 @@ int main(int argc, char **argv)
 			skel->rodata->suppress_dump = true;
 			break;
 		case 'p':
-			skel->rodata->switch_partial = true;
-			skel->struct_ops.qmap_ops->flags |= __COMPAT_SCX_OPS_SWITCH_PARTIAL;
+			skel->struct_ops.qmap_ops->flags |= SCX_OPS_SWITCH_PARTIAL;
 			break;
 		case 'v':
 			verbose = true;

tools/sched_ext/scx_simple.bpf.c

@@ -136,7 +136,6 @@ void BPF_STRUCT_OPS(simple_enable, struct task_struct *p)
 
 s32 BPF_STRUCT_OPS_SLEEPABLE(simple_init)
 {
-	__COMPAT_scx_bpf_switch_all();
 	return scx_bpf_create_dsq(SHARED_DSQ, -1);
 }