Commit eaedea15 authored by Menglong Dong's avatar Menglong Dong Committed by Alexei Starovoitov
Browse files

bpf, x86: inline bpf_get_current_task() for x86_64 



Inline bpf_get_current_task() and bpf_get_current_task_btf() for x86_64
to obtain better performance.

Signed-off-by: default avatarMenglong Dong <dongml2@chinatelecom.cn>
Acked-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260120070555.233486-2-dongml2@chinatelecom.cn


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 83c9030c

kernel/bpf/verifier.c

+22 −0
Original line number Diff line number Diff line
@@ -18130,6 +18130,10 @@ static bool verifier_inlines_helper_call(struct bpf_verifier_env *env, s32 imm) 
	switch (imm) {

#ifdef CONFIG_X86_64

	case BPF_FUNC_get_smp_processor_id:

#ifdef CONFIG_SMP

	case BPF_FUNC_get_current_task_btf:

	case BPF_FUNC_get_current_task:

#endif

		return env->prog->jit_requested && bpf_jit_supports_percpu_insn();

#endif

	default:
@@ -23715,6 +23719,24 @@ static int do_misc_fixups(struct bpf_verifier_env *env) 
			insn      = new_prog->insnsi + i + delta;

			goto next_insn;

		}









		/* Implement bpf_get_current_task() and bpf_get_current_task_btf() inline. */









		if ((insn->imm == BPF_FUNC_get_current_task || insn->imm == BPF_FUNC_get_current_task_btf) &&









		    verifier_inlines_helper_call(env, insn->imm)) {









			insn_buf[0] = BPF_MOV64_IMM(BPF_REG_0, (u32)(unsigned long)&current_task);









			insn_buf[1] = BPF_MOV64_PERCPU_REG(BPF_REG_0, BPF_REG_0);









			insn_buf[2] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0);









			cnt = 3;

















			new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt);









			if (!new_prog)









				return -ENOMEM;

















			delta    += cnt - 1;









			env->prog = prog = new_prog;









			insn      = new_prog->insnsi + i + delta;









			goto next_insn;









		}









#endif









		/* Implement bpf_get_func_arg inline. */









		if (prog_type == BPF_PROG_TYPE_TRACING &&