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

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright (c) 2024 Meta Platforms, Inc. and affiliates.
   4  * Copyright (c) 2024 Tejun Heo <tj@kernel.org>
   5  * Copyright (c) 2024 David Vernet <dvernet@meta.com>
   6  */
   7 #ifndef __SCX_COMPAT_BPF_H
   8 #define __SCX_COMPAT_BPF_H
   9
  10 #define __COMPAT_ENUM_OR_ZERO(__type, __ent)                                    \
  11 ({                                                                              \
  12         __type __ret = 0;                                                       \
  13         if (bpf_core_enum_value_exists(__type, __ent))                          \
  14                 __ret = __ent;                                                  \
  15         __ret;                                                                  \
  16 })
  17
  18 /* v6.12: 819513666966 ("sched_ext: Add cgroup support") */
  19 #define __COMPAT_scx_bpf_task_cgroup(p)                                         \
  20         (bpf_ksym_exists(scx_bpf_task_cgroup) ?                                 \
  21          scx_bpf_task_cgroup((p)) : NULL)
  22
  23 /*
  24  * v6.13: The verb `dispatch` was too overloaded and confusing. kfuncs are
  25  * renamed to unload the verb.
  26  *
  27  * Build error is triggered if old names are used. New binaries work with both
  28  * new and old names. The compat macros will be removed on v6.15 release.
  29  *
  30  * scx_bpf_dispatch_from_dsq() and friends were added during v6.12 by
  31  * 4c30f5ce4f7a ("sched_ext: Implement scx_bpf_dispatch[_vtime]_from_dsq()").
  32  * Preserve __COMPAT macros until v6.15.
  33  */
  34 void scx_bpf_dispatch___compat(struct task_struct *p, u64 dsq_id, u64 slice, u64 enq_flags) __ksym __weak;
  35 void scx_bpf_dispatch_vtime___compat(struct task_struct *p, u64 dsq_id, u64 slice, u64 vtime, u64 enq_flags) __ksym __weak;
  36 bool scx_bpf_consume___compat(u64 dsq_id) __ksym __weak;
  37 void scx_bpf_dispatch_from_dsq_set_slice___compat(struct bpf_iter_scx_dsq *it__iter, u64 slice) __ksym __weak;
  38 void scx_bpf_dispatch_from_dsq_set_vtime___compat(struct bpf_iter_scx_dsq *it__iter, u64 vtime) __ksym __weak;
  39 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;
  40 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;
  41
  42 #define scx_bpf_dsq_insert(p, dsq_id, slice, enq_flags)                         \
  43         (bpf_ksym_exists(scx_bpf_dsq_insert) ?                                  \
  44          scx_bpf_dsq_insert((p), (dsq_id), (slice), (enq_flags)) :              \
  45          scx_bpf_dispatch___compat((p), (dsq_id), (slice), (enq_flags)))
  46
  47 #define scx_bpf_dsq_insert_vtime(p, dsq_id, slice, vtime, enq_flags)            \
  48         (bpf_ksym_exists(scx_bpf_dsq_insert_vtime) ?                            \
  49          scx_bpf_dsq_insert_vtime((p), (dsq_id), (slice), (vtime), (enq_flags)) : \
  50          scx_bpf_dispatch_vtime___compat((p), (dsq_id), (slice), (vtime), (enq_flags)))
  51
  52 #define scx_bpf_dsq_move_to_local(dsq_id)                                       \
  53         (bpf_ksym_exists(scx_bpf_dsq_move_to_local) ?                           \
  54          scx_bpf_dsq_move_to_local((dsq_id)) :                                  \
  55          scx_bpf_consume___compat((dsq_id)))
  56
  57 #define __COMPAT_scx_bpf_dsq_move_set_slice(it__iter, slice)                    \
  58         (bpf_ksym_exists(scx_bpf_dsq_move_set_slice) ?                          \
  59          scx_bpf_dsq_move_set_slice((it__iter), (slice)) :                      \
  60          (bpf_ksym_exists(scx_bpf_dispatch_from_dsq_set_slice___compat) ?       \
  61           scx_bpf_dispatch_from_dsq_set_slice___compat((it__iter), (slice)) :   \
  62           (void)0))
  63
  64 #define __COMPAT_scx_bpf_dsq_move_set_vtime(it__iter, vtime)                    \
  65         (bpf_ksym_exists(scx_bpf_dsq_move_set_vtime) ?                          \
  66          scx_bpf_dsq_move_set_vtime((it__iter), (vtime)) :                      \
  67          (bpf_ksym_exists(scx_bpf_dispatch_from_dsq_set_vtime___compat) ?       \
  68           scx_bpf_dispatch_from_dsq_set_vtime___compat((it__iter), (vtime)) :   \
  69           (void) 0))
  70
  71 #define __COMPAT_scx_bpf_dsq_move(it__iter, p, dsq_id, enq_flags)               \
  72         (bpf_ksym_exists(scx_bpf_dsq_move) ?                                    \
  73          scx_bpf_dsq_move((it__iter), (p), (dsq_id), (enq_flags)) :             \
  74          (bpf_ksym_exists(scx_bpf_dispatch_from_dsq___compat) ?                 \
  75           scx_bpf_dispatch_from_dsq___compat((it__iter), (p), (dsq_id), (enq_flags)) : \
  76           false))
  77
  78 #define __COMPAT_scx_bpf_dsq_move_vtime(it__iter, p, dsq_id, enq_flags)         \
  79         (bpf_ksym_exists(scx_bpf_dsq_move_vtime) ?                              \
  80          scx_bpf_dsq_move_vtime((it__iter), (p), (dsq_id), (enq_flags)) :       \
  81          (bpf_ksym_exists(scx_bpf_dispatch_vtime_from_dsq___compat) ?           \
  82           scx_bpf_dispatch_vtime_from_dsq___compat((it__iter), (p), (dsq_id), (enq_flags)) : \
  83           false))
  84
  85 #define scx_bpf_dispatch(p, dsq_id, slice, enq_flags)                           \
  86         _Static_assert(false, "scx_bpf_dispatch() renamed to scx_bpf_dsq_insert()")
  87
  88 #define scx_bpf_dispatch_vtime(p, dsq_id, slice, vtime, enq_flags)              \
  89         _Static_assert(false, "scx_bpf_dispatch_vtime() renamed to scx_bpf_dsq_insert_vtime()")
  90
  91 #define scx_bpf_consume(dsq_id) ({                                              \
  92         _Static_assert(false, "scx_bpf_consume() renamed to scx_bpf_dsq_move_to_local()"); \
  93         false;                                                                  \
  94 })
  95
  96 #define scx_bpf_dispatch_from_dsq_set_slice(it__iter, slice)            \
  97         _Static_assert(false, "scx_bpf_dispatch_from_dsq_set_slice() renamed to scx_bpf_dsq_move_set_slice()")
  98
  99 #define scx_bpf_dispatch_from_dsq_set_vtime(it__iter, vtime)            \
 100         _Static_assert(false, "scx_bpf_dispatch_from_dsq_set_vtime() renamed to scx_bpf_dsq_move_set_vtime()")
 101
 102 #define scx_bpf_dispatch_from_dsq(it__iter, p, dsq_id, enq_flags) ({    \
 103         _Static_assert(false, "scx_bpf_dispatch_from_dsq() renamed to scx_bpf_dsq_move()"); \
 104         false;                                                                  \
 105 })
 106
 107 #define scx_bpf_dispatch_vtime_from_dsq(it__iter, p, dsq_id, enq_flags) ({  \
 108         _Static_assert(false, "scx_bpf_dispatch_vtime_from_dsq() renamed to scx_bpf_dsq_move_vtime()"); \
 109         false;                                                                  \
 110 })
 111
 112 #define __COMPAT_scx_bpf_dispatch_from_dsq_set_slice(it__iter, slice)           \
 113         _Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq_set_slice() renamed to __COMPAT_scx_bpf_dsq_move_set_slice()")
 114
 115 #define __COMPAT_scx_bpf_dispatch_from_dsq_set_vtime(it__iter, vtime)           \
 116         _Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq_set_vtime() renamed to __COMPAT_scx_bpf_dsq_move_set_vtime()")
 117
 118 #define __COMPAT_scx_bpf_dispatch_from_dsq(it__iter, p, dsq_id, enq_flags) ({   \
 119         _Static_assert(false, "__COMPAT_scx_bpf_dispatch_from_dsq() renamed to __COMPAT_scx_bpf_dsq_move()"); \
 120         false;                                                                  \
 121 })
 122
 123 #define __COMPAT_scx_bpf_dispatch_vtime_from_dsq(it__iter, p, dsq_id, enq_flags) ({  \
 124         _Static_assert(false, "__COMPAT_scx_bpf_dispatch_vtime_from_dsq() renamed to __COMPAT_scx_bpf_dsq_move_vtime()"); \
 125         false;                                                                  \
 126 })
 127
 128 /*
 129  * Define sched_ext_ops. This may be expanded to define multiple variants for
 130  * backward compatibility. See compat.h::SCX_OPS_LOAD/ATTACH().
 131  */
 132 #define SCX_OPS_DEFINE(__name, ...)                                             \
 133         SEC(".struct_ops.link")                                                 \
 134         struct sched_ext_ops __name = {                                         \
 135                 __VA_ARGS__,                                                    \
 136         };
 137
 138 #endif  /* __SCX_COMPAT_BPF_H */