diff options
Diffstat (limited to 'tools/sched_ext/include/scx/compat.bpf.h')
| -rw-r--r-- | tools/sched_ext/include/scx/compat.bpf.h | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/tools/sched_ext/include/scx/compat.bpf.h b/tools/sched_ext/include/scx/compat.bpf.h new file mode 100644 index 000000000000..9252e1a00556 --- /dev/null +++ b/tools/sched_ext/include/scx/compat.bpf.h @@ -0,0 +1,238 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2024 Meta Platforms, Inc. and affiliates. + * Copyright (c) 2024 Tejun Heo <tj@kernel.org> + * Copyright (c) 2024 David Vernet <dvernet@meta.com> + */ +#ifndef __SCX_COMPAT_BPF_H +#define __SCX_COMPAT_BPF_H + +#define __COMPAT_ENUM_OR_ZERO(__type, __ent) \ +({ \ + __type __ret = 0; \ + if (bpf_core_enum_value_exists(__type, __ent)) \ + __ret = __ent; \ + __ret; \ +}) + +/* v6.12: 819513666966 ("sched_ext: Add cgroup support") */ +#define __COMPAT_scx_bpf_task_cgroup(p) \ + (bpf_ksym_exists(scx_bpf_task_cgroup) ? \ + scx_bpf_task_cgroup((p)) : NULL) + +/* + * v6.13: The verb `dispatch` was too overloaded and confusing. kfuncs are + * renamed to unload the verb. + * + * Build error is triggered if old names are used. New binaries work with both + * new and old names. The compat macros will be removed on v6.15 release. + * + * scx_bpf_dispatch_from_dsq() and friends were added during v6.12 by + * 4c30f5ce4f7a ("sched_ext: Implement scx_bpf_dispatch[_vtime]_from_dsq()"). + * Preserve __COMPAT macros until v6.15. + */ +void scx_bpf_dispatch___compat(struct task_struct *p, u64 dsq_id, u64 slice, u64 enq_flags) __ksym __weak; +void scx_bpf_dispatch_vtime___compat(struct task_struct *p, u64 dsq_id, u64 slice, u64 vtime, u64 enq_flags) __ksym __weak; +bool scx_bpf_consume___compat(u64 dsq_id) __ksym __weak; +void scx_bpf_dispatch_from_dsq_set_slice___compat(struct bpf_iter_scx_dsq *it__iter, u64 slice) __ksym __weak; +void scx_bpf_dispatch_from_dsq_set_vtime___compat(struct bpf_iter_scx_dsq *it__iter, u64 vtime) __ksym __weak; +bool scx_bpf_dispatch_from_dsq___compat(struct bpf_iter_scx_dsq *it__iter, struct task_struct *p, u64 dsq_id, u64 enq_flags) __ksym __weak; +bool scx_bpf_dispatch_vtime_from_dsq___compat(struct bpf_iter_scx_dsq *it__iter, struct task_struct *p, u64 dsq_id, u64 enq_flags) __ksym __weak; + +#define scx_bpf_dsq_insert(p, dsq_id, slice, enq_flags) \ + (bpf_ksym_exists(scx_bpf_dsq_insert) ? \ + scx_bpf_dsq_insert((p), (dsq_id), (slice), (enq_flags)) : \ + scx_bpf_dispatch___compat((p), (dsq_id), (slice), (enq_flags))) + +#define scx_bpf_dsq_insert_vtime(p, dsq_id, slice, vtime, enq_flags) \ + (bpf_ksym_exists(scx_bpf_dsq_insert_vtime) ? \ + scx_bpf_dsq_insert_vtime((p), (dsq_id), (slice), (vtime), (enq_flags)) : \ + scx_bpf_dispatch_vtime___compat((p), (dsq_id), (slice), (vtime), (enq_flags))) + +#define scx_bpf_dsq_move_to_local(dsq_id) \ + (bpf_ksym_exists(scx_bpf_dsq_move_to_local) ? \ + scx_bpf_dsq_move_to_local((dsq_id)) : \ + scx_bpf_consume___compat((dsq_id))) + +#define __COMPAT_scx_bpf_dsq_move_set_slice(it__iter, slice) \ + (bpf_ksym_exists(scx_bpf_dsq_move_set_slice) ? \ + scx_bpf_dsq_move_set_slice((it__iter), (slice)) : \ + (bpf_ksym_exists(scx_bpf_dispatch_from_dsq_set_slice___compat) ? \ + scx_bpf_dispatch_from_dsq_set_slice___compat((it__iter), (slice)) : \ + (void)0)) + +#define __COMPAT_scx_bpf_dsq_move_set_vtime(it__iter, vtime) \ + (bpf_ksym_exists(scx_bpf_dsq_move_set_vtime) ? \ + scx_bpf_dsq_move_set_vtime((it__iter), (vtime)) : \ + (bpf_ksym_exists(scx_bpf_dispatch_from_dsq_set_vtime___compat) ? \ + scx_bpf_dispatch_from_dsq_set_vtime___compat((it__iter), (vtime)) : \ + (void) 0)) + +#define __COMPAT_scx_bpf_dsq_move(it__iter, p, dsq_id, enq_flags) \ + (bpf_ksym_exists(scx_bpf_dsq_move) ? \ + scx_bpf_dsq_move((it__iter), (p), (dsq_id), (enq_flags)) : \ + (bpf_ksym_exists(scx_bpf_dispatch_from_dsq___compat) ? \ + scx_bpf_dispatch_from_dsq___compat((it__iter), (p), (dsq_id), (enq_flags)) : \ + false)) + +#define __COMPAT_scx_bpf_dsq_move_vtime(it__iter, p, dsq_id, enq_flags) \ + (bpf_ksym_exists(scx_bpf_dsq_move_vtime) ? \ + scx_bpf_dsq_move_vtime((it__iter), (p), (dsq_id), (enq_flags)) : \ + (bpf_ksym_exists(scx_bpf_dispatch_vtime_from_dsq___compat) ? \ + scx_bpf_dispatch_vtime_from_dsq___compat((it__iter), (p), (dsq_id), (enq_flags)) : \ + false)) + +#define scx_bpf_dispatch(p, dsq_id, slice, enq_flags) \ + _Static_assert(false, "scx_bpf_dispatch() renamed to scx_bpf_dsq_insert()") + +#define scx_bpf_dispatch_vtime(p, dsq_id, slice, vtime, enq_flags) \ + _Static_assert(false, "scx_bpf_dispatch_vtime() renamed to scx_bpf_dsq_insert_vtime()") + +#define scx_bpf_consume(dsq_id) ({ \ + _Static_assert(false, "scx_bpf_consume() renamed to scx_bpf_dsq_move_to_local()"); \ + false; \ +}) + +#define scx_bpf_dispatch_from_dsq_set_slice(it__iter, slice) \ + _Static_assert(false, "scx_bpf_dispatch_from_dsq_set_slice() renamed to scx_bpf_dsq_move_set_slice()") + +#define scx_bpf_dispatch_from_dsq_set_vtime(it__iter, vtime) \ + _Static_assert(false, "scx_bpf_dispatch_from_dsq_set_vtime() renamed to scx_bpf_dsq_move_set_vtime()") + +#define scx_bpf_dispatch_from_dsq(it__iter, p, dsq_id, enq_flags) ({ \ + _Static_assert(false, "scx_bpf_dispatch_from_dsq() renamed to scx_bpf_dsq_move()"); \ + false; \ +}) + +#define scx_bpf_dispatch_vtime_from_dsq(it__iter, p, dsq_id, enq_flags) ({ \ + _Static_assert(false, "scx_bpf_dispatch_vtime_from_dsq() renamed to scx_bpf_dsq_move_vtime()"); \ + false; \ +}) + +#define __COMPAT_scx_bpf_dispatch_from_dsq_set_slice(it__iter, slice) \ + _Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq_set_slice() renamed to __COMPAT_scx_bpf_dsq_move_set_slice()") + +#define __COMPAT_scx_bpf_dispatch_from_dsq_set_vtime(it__iter, vtime) \ + _Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq_set_vtime() renamed to __COMPAT_scx_bpf_dsq_move_set_vtime()") + +#define __COMPAT_scx_bpf_dispatch_from_dsq(it__iter, p, dsq_id, enq_flags) ({ \ + _Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq() renamed to __COMPAT_scx_bpf_dsq_move()"); \ + false; \ +}) + +#define __COMPAT_scx_bpf_dispatch_vtime_from_dsq(it__iter, p, dsq_id, enq_flags) ({ \ + _Static_assert(false, "__COMPAT_scx_bpf_dispatch_vtime_from_dsq() renamed to __COMPAT_scx_bpf_dsq_move_vtime()"); \ + false; \ +}) + +/** + * __COMPAT_is_enq_cpu_selected - Test if SCX_ENQ_CPU_SELECTED is on + * in a compatible way. We will preserve this __COMPAT helper until v6.16. + * + * @enq_flags: enqueue flags from ops.enqueue() + * + * Return: True if SCX_ENQ_CPU_SELECTED is turned on in @enq_flags + */ +static inline bool __COMPAT_is_enq_cpu_selected(u64 enq_flags) +{ +#ifdef HAVE_SCX_ENQ_CPU_SELECTED + /* + * This is the case that a BPF code compiled against vmlinux.h + * where the enum SCX_ENQ_CPU_SELECTED exists. + */ + + /* + * We should temporarily suspend the macro expansion of + * 'SCX_ENQ_CPU_SELECTED'. This avoids 'SCX_ENQ_CPU_SELECTED' being + * rewritten to '__SCX_ENQ_CPU_SELECTED' when 'SCX_ENQ_CPU_SELECTED' + * is defined in 'scripts/gen_enums.py'. + */ +#pragma push_macro("SCX_ENQ_CPU_SELECTED") +#undef SCX_ENQ_CPU_SELECTED + u64 flag; + + /* + * When the kernel did not have SCX_ENQ_CPU_SELECTED, + * select_task_rq_scx() has never been skipped. Thus, this case + * should be considered that the CPU has already been selected. + */ + if (!bpf_core_enum_value_exists(enum scx_enq_flags, + SCX_ENQ_CPU_SELECTED)) + return true; + + flag = bpf_core_enum_value(enum scx_enq_flags, SCX_ENQ_CPU_SELECTED); + return enq_flags & flag; + + /* + * Once done, resume the macro expansion of 'SCX_ENQ_CPU_SELECTED'. + */ +#pragma pop_macro("SCX_ENQ_CPU_SELECTED") +#else + /* + * This is the case that a BPF code compiled against vmlinux.h + * where the enum SCX_ENQ_CPU_SELECTED does NOT exist. + */ + return true; +#endif /* HAVE_SCX_ENQ_CPU_SELECTED */ +} + + +#define scx_bpf_now() \ + (bpf_ksym_exists(scx_bpf_now) ? \ + scx_bpf_now() : \ + bpf_ktime_get_ns()) + +/* + * v6.15: Introduce event counters. + * + * Preserve the following macro until v6.17. + */ +#define __COMPAT_scx_bpf_events(events, size) \ + (bpf_ksym_exists(scx_bpf_events) ? \ + scx_bpf_events(events, size) : ({})) + +/* + * v6.15: Introduce NUMA-aware kfuncs to operate with per-node idle + * cpumasks. + * + * Preserve the following __COMPAT_scx_*_node macros until v6.17. + */ +#define __COMPAT_scx_bpf_nr_node_ids() \ + (bpf_ksym_exists(scx_bpf_nr_node_ids) ? \ + scx_bpf_nr_node_ids() : 1U) + +#define __COMPAT_scx_bpf_cpu_node(cpu) \ + (bpf_ksym_exists(scx_bpf_cpu_node) ? \ + scx_bpf_cpu_node(cpu) : 0) + +#define __COMPAT_scx_bpf_get_idle_cpumask_node(node) \ + (bpf_ksym_exists(scx_bpf_get_idle_cpumask_node) ? \ + scx_bpf_get_idle_cpumask_node(node) : \ + scx_bpf_get_idle_cpumask()) \ + +#define __COMPAT_scx_bpf_get_idle_smtmask_node(node) \ + (bpf_ksym_exists(scx_bpf_get_idle_smtmask_node) ? \ + scx_bpf_get_idle_smtmask_node(node) : \ + scx_bpf_get_idle_smtmask()) + +#define __COMPAT_scx_bpf_pick_idle_cpu_node(cpus_allowed, node, flags) \ + (bpf_ksym_exists(scx_bpf_pick_idle_cpu_node) ? \ + scx_bpf_pick_idle_cpu_node(cpus_allowed, node, flags) : \ + scx_bpf_pick_idle_cpu(cpus_allowed, flags)) + +#define __COMPAT_scx_bpf_pick_any_cpu_node(cpus_allowed, node, flags) \ + (bpf_ksym_exists(scx_bpf_pick_any_cpu_node) ? \ + scx_bpf_pick_any_cpu_node(cpus_allowed, node, flags) : \ + scx_bpf_pick_any_cpu(cpus_allowed, flags)) + +/* + * Define sched_ext_ops. This may be expanded to define multiple variants for + * backward compatibility. See compat.h::SCX_OPS_LOAD/ATTACH(). + */ +#define SCX_OPS_DEFINE(__name, ...) \ + SEC(".struct_ops.link") \ + struct sched_ext_ops __name = { \ + __VA_ARGS__, \ + }; + +#endif /* __SCX_COMPAT_BPF_H */ |