Commit ae0a457f authored by Emil Tsalapatis's avatar Emil Tsalapatis Committed by Alexei Starovoitov
Browse files

bpf: Make perf_event_read_output accessible in all program types. 



The perf_event_read_event_output helper is currently only available to
tracing protrams, but is useful for other BPF programs like sched_ext
schedulers. When the helper is available, provide its bpf_func_proto
directly from the bpf base_proto.

Signed-off-by: default avatarEmil Tsalapatis (Meta) <emil@etsalapatis.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20250318030753.10949-1-emil@etsalapatis.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent f3f86495

include/linux/bpf.h

+2 −0
Original line number Diff line number Diff line
@@ -2059,6 +2059,8 @@ int bpf_prog_calc_tag(struct bpf_prog *fp); 
const struct bpf_func_proto *bpf_get_trace_printk_proto(void);

const struct bpf_func_proto *bpf_get_trace_vprintk_proto(void);



const struct bpf_func_proto *bpf_get_perf_event_read_value_proto(void);



typedef unsigned long (*bpf_ctx_copy_t)(void *dst, const void *src,

					unsigned long off, unsigned long len);

typedef u32 (*bpf_convert_ctx_access_t)(enum bpf_access_type type,

kernel/bpf/core.c

+5 −0
Original line number Diff line number Diff line
@@ -2972,6 +2972,11 @@ const struct bpf_func_proto * __weak bpf_get_trace_vprintk_proto(void) 
	return NULL;

}



const struct bpf_func_proto * __weak bpf_get_perf_event_read_value_proto(void)

{

	return NULL;

}



u64 __weak

bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,

		 void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)

kernel/bpf/helpers.c

+2 −0
Original line number Diff line number Diff line
@@ -2056,6 +2056,8 @@ bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 
		return &bpf_task_pt_regs_proto;

	case BPF_FUNC_trace_vprintk:

		return bpf_get_trace_vprintk_proto();

	case BPF_FUNC_perf_event_read_value:

		return bpf_get_perf_event_read_value_proto();

	default:

		return NULL;

	}

kernel/trace/bpf_trace.c

+5 −0
Original line number Diff line number Diff line
@@ -607,6 +607,11 @@ static const struct bpf_func_proto bpf_perf_event_read_value_proto = { 
	.arg4_type	= ARG_CONST_SIZE,

};



const struct bpf_func_proto *bpf_get_perf_event_read_value_proto(void)

{

	return &bpf_perf_event_read_value_proto;

}



static __always_inline u64

__bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,

			u64 flags, struct perf_raw_record *raw,