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Diffstat (limited to 'tools/sched_ext/include/scx/common.bpf.h')
| -rw-r--r-- | tools/sched_ext/include/scx/common.bpf.h | 412 |
1 files changed, 412 insertions, 0 deletions
diff --git a/tools/sched_ext/include/scx/common.bpf.h b/tools/sched_ext/include/scx/common.bpf.h new file mode 100644 index 000000000000..f538c75db183 --- /dev/null +++ b/tools/sched_ext/include/scx/common.bpf.h @@ -0,0 +1,412 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2022 Meta Platforms, Inc. and affiliates. + * Copyright (c) 2022 Tejun Heo <tj@kernel.org> + * Copyright (c) 2022 David Vernet <dvernet@meta.com> + */ +#ifndef __SCX_COMMON_BPF_H +#define __SCX_COMMON_BPF_H + +#include "vmlinux.h" +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> +#include <asm-generic/errno.h> +#include "user_exit_info.h" + +#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ +#define PF_KTHREAD 0x00200000 /* I am a kernel thread */ +#define PF_EXITING 0x00000004 +#define CLOCK_MONOTONIC 1 + +/* + * Earlier versions of clang/pahole lost upper 32bits in 64bit enums which can + * lead to really confusing misbehaviors. Let's trigger a build failure. + */ +static inline void ___vmlinux_h_sanity_check___(void) +{ + _Static_assert(SCX_DSQ_FLAG_BUILTIN, + "bpftool generated vmlinux.h is missing high bits for 64bit enums, upgrade clang and pahole"); +} + +s32 scx_bpf_create_dsq(u64 dsq_id, s32 node) __ksym; +s32 scx_bpf_select_cpu_dfl(struct task_struct *p, s32 prev_cpu, u64 wake_flags, bool *is_idle) __ksym; +void scx_bpf_dispatch(struct task_struct *p, u64 dsq_id, u64 slice, u64 enq_flags) __ksym; +void scx_bpf_dispatch_vtime(struct task_struct *p, u64 dsq_id, u64 slice, u64 vtime, u64 enq_flags) __ksym; +u32 scx_bpf_dispatch_nr_slots(void) __ksym; +void scx_bpf_dispatch_cancel(void) __ksym; +bool scx_bpf_consume(u64 dsq_id) __ksym; +void scx_bpf_dispatch_from_dsq_set_slice(struct bpf_iter_scx_dsq *it__iter, u64 slice) __ksym; +void scx_bpf_dispatch_from_dsq_set_vtime(struct bpf_iter_scx_dsq *it__iter, u64 vtime) __ksym; +bool scx_bpf_dispatch_from_dsq(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(struct bpf_iter_scx_dsq *it__iter, struct task_struct *p, u64 dsq_id, u64 enq_flags) __ksym __weak; +u32 scx_bpf_reenqueue_local(void) __ksym; +void scx_bpf_kick_cpu(s32 cpu, u64 flags) __ksym; +s32 scx_bpf_dsq_nr_queued(u64 dsq_id) __ksym; +void scx_bpf_destroy_dsq(u64 dsq_id) __ksym; +int bpf_iter_scx_dsq_new(struct bpf_iter_scx_dsq *it, u64 dsq_id, u64 flags) __ksym __weak; +struct task_struct *bpf_iter_scx_dsq_next(struct bpf_iter_scx_dsq *it) __ksym __weak; +void bpf_iter_scx_dsq_destroy(struct bpf_iter_scx_dsq *it) __ksym __weak; +void scx_bpf_exit_bstr(s64 exit_code, char *fmt, unsigned long long *data, u32 data__sz) __ksym __weak; +void scx_bpf_error_bstr(char *fmt, unsigned long long *data, u32 data_len) __ksym; +void scx_bpf_dump_bstr(char *fmt, unsigned long long *data, u32 data_len) __ksym __weak; +u32 scx_bpf_cpuperf_cap(s32 cpu) __ksym __weak; +u32 scx_bpf_cpuperf_cur(s32 cpu) __ksym __weak; +void scx_bpf_cpuperf_set(s32 cpu, u32 perf) __ksym __weak; +u32 scx_bpf_nr_cpu_ids(void) __ksym __weak; +const struct cpumask *scx_bpf_get_possible_cpumask(void) __ksym __weak; +const struct cpumask *scx_bpf_get_online_cpumask(void) __ksym __weak; +void scx_bpf_put_cpumask(const struct cpumask *cpumask) __ksym __weak; +const struct cpumask *scx_bpf_get_idle_cpumask(void) __ksym; +const struct cpumask *scx_bpf_get_idle_smtmask(void) __ksym; +void scx_bpf_put_idle_cpumask(const struct cpumask *cpumask) __ksym; +bool scx_bpf_test_and_clear_cpu_idle(s32 cpu) __ksym; +s32 scx_bpf_pick_idle_cpu(const cpumask_t *cpus_allowed, u64 flags) __ksym; +s32 scx_bpf_pick_any_cpu(const cpumask_t *cpus_allowed, u64 flags) __ksym; +bool scx_bpf_task_running(const struct task_struct *p) __ksym; +s32 scx_bpf_task_cpu(const struct task_struct *p) __ksym; +struct rq *scx_bpf_cpu_rq(s32 cpu) __ksym; +struct cgroup *scx_bpf_task_cgroup(struct task_struct *p) __ksym; + +/* + * Use the following as @it__iter when calling + * scx_bpf_dispatch[_vtime]_from_dsq() from within bpf_for_each() loops. + */ +#define BPF_FOR_EACH_ITER (&___it) + +static inline __attribute__((format(printf, 1, 2))) +void ___scx_bpf_bstr_format_checker(const char *fmt, ...) {} + +/* + * Helper macro for initializing the fmt and variadic argument inputs to both + * bstr exit kfuncs. Callers to this function should use ___fmt and ___param to + * refer to the initialized list of inputs to the bstr kfunc. + */ +#define scx_bpf_bstr_preamble(fmt, args...) \ + static char ___fmt[] = fmt; \ + /* \ + * Note that __param[] must have at least one \ + * element to keep the verifier happy. \ + */ \ + unsigned long long ___param[___bpf_narg(args) ?: 1] = {}; \ + \ + _Pragma("GCC diagnostic push") \ + _Pragma("GCC diagnostic ignored \"-Wint-conversion\"") \ + ___bpf_fill(___param, args); \ + _Pragma("GCC diagnostic pop") \ + +/* + * scx_bpf_exit() wraps the scx_bpf_exit_bstr() kfunc with variadic arguments + * instead of an array of u64. Using this macro will cause the scheduler to + * exit cleanly with the specified exit code being passed to user space. + */ +#define scx_bpf_exit(code, fmt, args...) \ +({ \ + scx_bpf_bstr_preamble(fmt, args) \ + scx_bpf_exit_bstr(code, ___fmt, ___param, sizeof(___param)); \ + ___scx_bpf_bstr_format_checker(fmt, ##args); \ +}) + +/* + * scx_bpf_error() wraps the scx_bpf_error_bstr() kfunc with variadic arguments + * instead of an array of u64. Invoking this macro will cause the scheduler to + * exit in an erroneous state, with diagnostic information being passed to the + * user. + */ +#define scx_bpf_error(fmt, args...) \ +({ \ + scx_bpf_bstr_preamble(fmt, args) \ + scx_bpf_error_bstr(___fmt, ___param, sizeof(___param)); \ + ___scx_bpf_bstr_format_checker(fmt, ##args); \ +}) + +/* + * scx_bpf_dump() wraps the scx_bpf_dump_bstr() kfunc with variadic arguments + * instead of an array of u64. To be used from ops.dump() and friends. + */ +#define scx_bpf_dump(fmt, args...) \ +({ \ + scx_bpf_bstr_preamble(fmt, args) \ + scx_bpf_dump_bstr(___fmt, ___param, sizeof(___param)); \ + ___scx_bpf_bstr_format_checker(fmt, ##args); \ +}) + +#define BPF_STRUCT_OPS(name, args...) \ +SEC("struct_ops/"#name) \ +BPF_PROG(name, ##args) + +#define BPF_STRUCT_OPS_SLEEPABLE(name, args...) \ +SEC("struct_ops.s/"#name) \ +BPF_PROG(name, ##args) + +/** + * RESIZABLE_ARRAY - Generates annotations for an array that may be resized + * @elfsec: the data section of the BPF program in which to place the array + * @arr: the name of the array + * + * libbpf has an API for setting map value sizes. Since data sections (i.e. + * bss, data, rodata) themselves are maps, a data section can be resized. If + * a data section has an array as its last element, the BTF info for that + * array will be adjusted so that length of the array is extended to meet the + * new length of the data section. This macro annotates an array to have an + * element count of one with the assumption that this array can be resized + * within the userspace program. It also annotates the section specifier so + * this array exists in a custom sub data section which can be resized + * independently. + * + * See RESIZE_ARRAY() for the userspace convenience macro for resizing an + * array declared with RESIZABLE_ARRAY(). + */ +#define RESIZABLE_ARRAY(elfsec, arr) arr[1] SEC("."#elfsec"."#arr) + +/** + * MEMBER_VPTR - Obtain the verified pointer to a struct or array member + * @base: struct or array to index + * @member: dereferenced member (e.g. .field, [idx0][idx1], .field[idx0] ...) + * + * The verifier often gets confused by the instruction sequence the compiler + * generates for indexing struct fields or arrays. This macro forces the + * compiler to generate a code sequence which first calculates the byte offset, + * checks it against the struct or array size and add that byte offset to + * generate the pointer to the member to help the verifier. + * + * Ideally, we want to abort if the calculated offset is out-of-bounds. However, + * BPF currently doesn't support abort, so evaluate to %NULL instead. The caller + * must check for %NULL and take appropriate action to appease the verifier. To + * avoid confusing the verifier, it's best to check for %NULL and dereference + * immediately. + * + * vptr = MEMBER_VPTR(my_array, [i][j]); + * if (!vptr) + * return error; + * *vptr = new_value; + * + * sizeof(@base) should encompass the memory area to be accessed and thus can't + * be a pointer to the area. Use `MEMBER_VPTR(*ptr, .member)` instead of + * `MEMBER_VPTR(ptr, ->member)`. + */ +#define MEMBER_VPTR(base, member) (typeof((base) member) *) \ +({ \ + u64 __base = (u64)&(base); \ + u64 __addr = (u64)&((base) member) - __base; \ + _Static_assert(sizeof(base) >= sizeof((base) member), \ + "@base is smaller than @member, is @base a pointer?"); \ + asm volatile ( \ + "if %0 <= %[max] goto +2\n" \ + "%0 = 0\n" \ + "goto +1\n" \ + "%0 += %1\n" \ + : "+r"(__addr) \ + : "r"(__base), \ + [max]"i"(sizeof(base) - sizeof((base) member))); \ + __addr; \ +}) + +/** + * ARRAY_ELEM_PTR - Obtain the verified pointer to an array element + * @arr: array to index into + * @i: array index + * @n: number of elements in array + * + * Similar to MEMBER_VPTR() but is intended for use with arrays where the + * element count needs to be explicit. + * It can be used in cases where a global array is defined with an initial + * size but is intended to be be resized before loading the BPF program. + * Without this version of the macro, MEMBER_VPTR() will use the compile time + * size of the array to compute the max, which will result in rejection by + * the verifier. + */ +#define ARRAY_ELEM_PTR(arr, i, n) (typeof(arr[i]) *) \ +({ \ + u64 __base = (u64)arr; \ + u64 __addr = (u64)&(arr[i]) - __base; \ + asm volatile ( \ + "if %0 <= %[max] goto +2\n" \ + "%0 = 0\n" \ + "goto +1\n" \ + "%0 += %1\n" \ + : "+r"(__addr) \ + : "r"(__base), \ + [max]"r"(sizeof(arr[0]) * ((n) - 1))); \ + __addr; \ +}) + + +/* + * BPF declarations and helpers + */ + +/* list and rbtree */ +#define __contains(name, node) __attribute__((btf_decl_tag("contains:" #name ":" #node))) +#define private(name) SEC(".data." #name) __hidden __attribute__((aligned(8))) + +void *bpf_obj_new_impl(__u64 local_type_id, void *meta) __ksym; +void bpf_obj_drop_impl(void *kptr, void *meta) __ksym; + +#define bpf_obj_new(type) ((type *)bpf_obj_new_impl(bpf_core_type_id_local(type), NULL)) +#define bpf_obj_drop(kptr) bpf_obj_drop_impl(kptr, NULL) + +void bpf_list_push_front(struct bpf_list_head *head, struct bpf_list_node *node) __ksym; +void bpf_list_push_back(struct bpf_list_head *head, struct bpf_list_node *node) __ksym; +struct bpf_list_node *bpf_list_pop_front(struct bpf_list_head *head) __ksym; +struct bpf_list_node *bpf_list_pop_back(struct bpf_list_head *head) __ksym; +struct bpf_rb_node *bpf_rbtree_remove(struct bpf_rb_root *root, + struct bpf_rb_node *node) __ksym; +int bpf_rbtree_add_impl(struct bpf_rb_root *root, struct bpf_rb_node *node, + bool (less)(struct bpf_rb_node *a, const struct bpf_rb_node *b), + void *meta, __u64 off) __ksym; +#define bpf_rbtree_add(head, node, less) bpf_rbtree_add_impl(head, node, less, NULL, 0) + +struct bpf_rb_node *bpf_rbtree_first(struct bpf_rb_root *root) __ksym; + +void *bpf_refcount_acquire_impl(void *kptr, void *meta) __ksym; +#define bpf_refcount_acquire(kptr) bpf_refcount_acquire_impl(kptr, NULL) + +/* task */ +struct task_struct *bpf_task_from_pid(s32 pid) __ksym; +struct task_struct *bpf_task_acquire(struct task_struct *p) __ksym; +void bpf_task_release(struct task_struct *p) __ksym; + +/* cgroup */ +struct cgroup *bpf_cgroup_ancestor(struct cgroup *cgrp, int level) __ksym; +void bpf_cgroup_release(struct cgroup *cgrp) __ksym; +struct cgroup *bpf_cgroup_from_id(u64 cgid) __ksym; + +/* css iteration */ +struct bpf_iter_css; +struct cgroup_subsys_state; +extern int bpf_iter_css_new(struct bpf_iter_css *it, + struct cgroup_subsys_state *start, + unsigned int flags) __weak __ksym; +extern struct cgroup_subsys_state * +bpf_iter_css_next(struct bpf_iter_css *it) __weak __ksym; +extern void bpf_iter_css_destroy(struct bpf_iter_css *it) __weak __ksym; + +/* cpumask */ +struct bpf_cpumask *bpf_cpumask_create(void) __ksym; +struct bpf_cpumask *bpf_cpumask_acquire(struct bpf_cpumask *cpumask) __ksym; +void bpf_cpumask_release(struct bpf_cpumask *cpumask) __ksym; +u32 bpf_cpumask_first(const struct cpumask *cpumask) __ksym; +u32 bpf_cpumask_first_zero(const struct cpumask *cpumask) __ksym; +void bpf_cpumask_set_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym; +void bpf_cpumask_clear_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym; +bool bpf_cpumask_test_cpu(u32 cpu, const struct cpumask *cpumask) __ksym; +bool bpf_cpumask_test_and_set_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym; +bool bpf_cpumask_test_and_clear_cpu(u32 cpu, struct bpf_cpumask *cpumask) __ksym; +void bpf_cpumask_setall(struct bpf_cpumask *cpumask) __ksym; +void bpf_cpumask_clear(struct bpf_cpumask *cpumask) __ksym; +bool bpf_cpumask_and(struct bpf_cpumask *dst, const struct cpumask *src1, + const struct cpumask *src2) __ksym; +void bpf_cpumask_or(struct bpf_cpumask *dst, const struct cpumask *src1, + const struct cpumask *src2) __ksym; +void bpf_cpumask_xor(struct bpf_cpumask *dst, const struct cpumask *src1, + const struct cpumask *src2) __ksym; +bool bpf_cpumask_equal(const struct cpumask *src1, const struct cpumask *src2) __ksym; +bool bpf_cpumask_intersects(const struct cpumask *src1, const struct cpumask *src2) __ksym; +bool bpf_cpumask_subset(const struct cpumask *src1, const struct cpumask *src2) __ksym; +bool bpf_cpumask_empty(const struct cpumask *cpumask) __ksym; +bool bpf_cpumask_full(const struct cpumask *cpumask) __ksym; +void bpf_cpumask_copy(struct bpf_cpumask *dst, const struct cpumask *src) __ksym; +u32 bpf_cpumask_any_distribute(const struct cpumask *cpumask) __ksym; +u32 bpf_cpumask_any_and_distribute(const struct cpumask *src1, + const struct cpumask *src2) __ksym; + +/* rcu */ +void bpf_rcu_read_lock(void) __ksym; +void bpf_rcu_read_unlock(void) __ksym; + + +/* + * Other helpers + */ + +/* useful compiler attributes */ +#define likely(x) __builtin_expect(!!(x), 1) +#define unlikely(x) __builtin_expect(!!(x), 0) +#define __maybe_unused __attribute__((__unused__)) + +/* + * READ/WRITE_ONCE() are from kernel (include/asm-generic/rwonce.h). They + * prevent compiler from caching, redoing or reordering reads or writes. + */ +typedef __u8 __attribute__((__may_alias__)) __u8_alias_t; +typedef __u16 __attribute__((__may_alias__)) __u16_alias_t; +typedef __u32 __attribute__((__may_alias__)) __u32_alias_t; +typedef __u64 __attribute__((__may_alias__)) __u64_alias_t; + +static __always_inline void __read_once_size(const volatile void *p, void *res, int size) +{ + switch (size) { + case 1: *(__u8_alias_t *) res = *(volatile __u8_alias_t *) p; break; + case 2: *(__u16_alias_t *) res = *(volatile __u16_alias_t *) p; break; + case 4: *(__u32_alias_t *) res = *(volatile __u32_alias_t *) p; break; + case 8: *(__u64_alias_t *) res = *(volatile __u64_alias_t *) p; break; + default: + barrier(); + __builtin_memcpy((void *)res, (const void *)p, size); + barrier(); + } +} + +static __always_inline void __write_once_size(volatile void *p, void *res, int size) +{ + switch (size) { + case 1: *(volatile __u8_alias_t *) p = *(__u8_alias_t *) res; break; + case 2: *(volatile __u16_alias_t *) p = *(__u16_alias_t *) res; break; + case 4: *(volatile __u32_alias_t *) p = *(__u32_alias_t *) res; break; + case 8: *(volatile __u64_alias_t *) p = *(__u64_alias_t *) res; break; + default: + barrier(); + __builtin_memcpy((void *)p, (const void *)res, size); + barrier(); + } +} + +#define READ_ONCE(x) \ +({ \ + union { typeof(x) __val; char __c[1]; } __u = \ + { .__c = { 0 } }; \ + __read_once_size(&(x), __u.__c, sizeof(x)); \ + __u.__val; \ +}) + +#define WRITE_ONCE(x, val) \ +({ \ + union { typeof(x) __val; char __c[1]; } __u = \ + { .__val = (val) }; \ + __write_once_size(&(x), __u.__c, sizeof(x)); \ + __u.__val; \ +}) + +/* + * log2_u32 - Compute the base 2 logarithm of a 32-bit exponential value. + * @v: The value for which we're computing the base 2 logarithm. + */ +static inline u32 log2_u32(u32 v) +{ + u32 r; + u32 shift; + + r = (v > 0xFFFF) << 4; v >>= r; + shift = (v > 0xFF) << 3; v >>= shift; r |= shift; + shift = (v > 0xF) << 2; v >>= shift; r |= shift; + shift = (v > 0x3) << 1; v >>= shift; r |= shift; + r |= (v >> 1); + return r; +} + +/* + * log2_u64 - Compute the base 2 logarithm of a 64-bit exponential value. + * @v: The value for which we're computing the base 2 logarithm. + */ +static inline u32 log2_u64(u64 v) +{ + u32 hi = v >> 32; + if (hi) + return log2_u32(hi) + 32 + 1; + else + return log2_u32(v) + 1; +} + +#include "compat.bpf.h" + +#endif /* __SCX_COMMON_BPF_H */ |