From: Yonghong Song <yonghong.song@linux.dev>
To: bpf@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>,
Andrii Nakryiko <andrii@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Eduard Zingerman <eddyz87@gmail.com>,
kernel-team@fb.com
Subject: [PATCH bpf-next v2 05/12] bpf: Rename bpf_call_summary::num_params to arg_slot_cnt
Date: Tue, 8 Sep 2026 23:25:48 -0700 [thread overview]
Message-ID: <20260909062548.4005732-1-yonghong.song@linux.dev> (raw)
In-Reply-To: <20260909062522.4001896-1-yonghong.song@linux.dev>
The field 'num_params' counts the argument registers and outgoing
stack slots a helper or kfunc call takes. The next patch gives a
16-byte parameter two slots, so the name stops describing what the
field holds.
Rename 'num_params' to 'arg_slot_cnt'. No functional change.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
---
include/linux/bpf_verifier.h | 2 +-
kernel/bpf/liveness.c | 10 +++++-----
kernel/bpf/verifier.c | 8 ++++----
3 files changed, 10 insertions(+), 10 deletions(-)
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 9727df5af83a..0a857793c134 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -1066,7 +1066,7 @@ static inline bool bpf_ret_reg_pair(struct bpf_verifier_env *env, int subprog)
}
struct bpf_call_summary {
- u8 num_params;
+ u8 arg_slot_cnt;
bool is_void;
bool fastcall;
};
diff --git a/kernel/bpf/liveness.c b/kernel/bpf/liveness.c
index 7165ea325961..44ecdc5b4ec2 100644
--- a/kernel/bpf/liveness.c
+++ b/kernel/bpf/liveness.c
@@ -1434,21 +1434,21 @@ static int record_call_access(struct bpf_verifier_env *env,
{
struct bpf_insn *insn = &env->prog->insnsi[insn_idx];
struct bpf_call_summary cs;
- int r, err, num_params = 5;
+ int r, err, arg_slot_cnt = 5;
if (bpf_pseudo_call(insn))
return 0;
if (bpf_get_call_summary(env, insn, &cs))
- num_params = cs.num_params;
+ arg_slot_cnt = cs.arg_slot_cnt;
- for (r = BPF_REG_1; r < BPF_REG_1 + min(num_params, MAX_BPF_FUNC_REG_ARGS); r++) {
+ for (r = BPF_REG_1; r < BPF_REG_1 + min(arg_slot_cnt, MAX_BPF_FUNC_REG_ARGS); r++) {
err = record_arg_access(env, instance, insn, &at[r], r - 1, insn_idx);
if (err)
return err;
}
- for (r = 0; r < MAX_STACK_ARG_SLOTS && r < num_params - MAX_BPF_FUNC_REG_ARGS; r++) {
+ for (r = 0; r < MAX_STACK_ARG_SLOTS && r < arg_slot_cnt - MAX_BPF_FUNC_REG_ARGS; r++) {
err = record_arg_access(env, instance, insn, &at[MAX_BPF_REG + r],
r + MAX_BPF_FUNC_REG_ARGS, insn_idx);
if (err)
@@ -2199,7 +2199,7 @@ static void compute_insn_live_regs(struct bpf_verifier_env *env,
def = ALL_CALLER_SAVED_REGS;
use = def & ~BIT(BPF_REG_0);
if (bpf_get_call_summary(env, insn, &cs))
- use = GENMASK(min_t(u8, cs.num_params, MAX_BPF_FUNC_REG_ARGS), 1);
+ use = GENMASK(min_t(u8, cs.arg_slot_cnt, MAX_BPF_FUNC_REG_ARGS), 1);
def = mask_widen(def);
use = mask_widen(use);
break;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index a9243066a114..cf526f28f3e5 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -17977,11 +17977,11 @@ bool bpf_get_call_summary(struct bpf_verifier_env *env, struct bpf_insn *call,
(bpf_verifier_inlines_helper_call(env, call->imm) ||
bpf_jit_inlines_helper_call(call->imm));
cs->is_void = fn->ret_type == RET_VOID;
- cs->num_params = 0;
+ cs->arg_slot_cnt = 0;
for (i = 0; i < ARRAY_SIZE(fn->arg_type); ++i) {
if (fn->arg_type[i] == ARG_DONTCARE)
break;
- cs->num_params++;
+ cs->arg_slot_cnt++;
}
return true;
}
@@ -17993,7 +17993,7 @@ bool bpf_get_call_summary(struct bpf_verifier_env *env, struct bpf_insn *call,
if (err < 0)
/* error would be reported later */
return false;
- cs->num_params = btf_type_vlen(meta.func_proto);
+ cs->arg_slot_cnt = btf_type_vlen(meta.func_proto);
cs->fastcall = meta.kfunc_flags & KF_FASTCALL;
cs->is_void = btf_type_is_void(btf_type_by_id(meta.btf, meta.func_proto->type));
return true;
@@ -18102,7 +18102,7 @@ static void mark_fastcall_pattern_for_call(struct bpf_verifier_env *env,
* - includes R1-R5 if corresponding parameter has is described
* in the function prototype.
*/
- clobbered_regs_mask = GENMASK(cs.num_params, cs.is_void ? 1 : 0);
+ clobbered_regs_mask = GENMASK(cs.arg_slot_cnt, cs.is_void ? 1 : 0);
/* e.g. if helper call clobbers r{0,1}, expect r{2,3,4,5} in the pattern */
expected_regs_mask = ~clobbered_regs_mask & ALL_CALLER_SAVED_REGS;
--
2.53.0-Meta
next prev parent reply other threads:[~2026-09-09 6:26 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-09 6:25 [PATCH bpf-next v2 00/12] bpf: Support by-value struct and __int128 arguments Yonghong Song
2026-09-09 6:25 ` [PATCH bpf-next v2 01/12] selftests/bpf: Add a test for an __int128 by-value argument Yonghong Song
2026-09-09 7:13 ` bot+bpf-ci
2026-09-11 4:25 ` Yonghong Song
2026-09-09 6:25 ` [PATCH bpf-next v2 02/12] bpf: Index global function arguments by argument slot Yonghong Song
2026-09-09 7:13 ` bot+bpf-ci
2026-09-11 4:27 ` Yonghong Song
2026-09-09 6:25 ` [PATCH bpf-next v2 03/12] bpf: Support by-value struct arguments up to 16 bytes Yonghong Song
2026-09-09 7:13 ` bot+bpf-ci
2026-09-11 4:29 ` Yonghong Song
2026-09-09 6:25 ` [PATCH bpf-next v2 04/12] bpf: Support __int128 as a by-value function argument Yonghong Song
2026-09-09 6:25 ` Yonghong Song [this message]
2026-09-09 6:25 ` [PATCH bpf-next v2 06/12] bpf: Recognize by-value struct and __int128 kfunc arguments Yonghong Song
2026-09-09 6:46 ` sashiko-bot
2026-09-11 4:31 ` Yonghong Song
2026-09-09 6:25 ` [PATCH bpf-next v2 07/12] bpf: Prepare kfunc arguments for the JIT from an ABI description Yonghong Song
2026-09-09 6:46 ` sashiko-bot
2026-09-11 5:05 ` Yonghong Song
2026-09-09 6:26 ` [PATCH bpf-next v2 08/12] bpf, x86: Move kfunc arguments into the x86-64 calling convention Yonghong Song
2026-09-09 7:29 ` bot+bpf-ci
2026-09-11 5:32 ` Yonghong Song
2026-09-09 6:26 ` [PATCH bpf-next v2 09/12] bpf, arm64: Move kfunc arguments into the arm64 " Yonghong Song
2026-09-09 7:30 ` bot+bpf-ci
2026-09-11 5:34 ` Yonghong Song
2026-09-09 6:26 ` [PATCH bpf-next v2 10/12] selftests/bpf: Add C tests for by-value arguments up to 16 bytes Yonghong Song
2026-09-09 6:26 ` [PATCH bpf-next v2 11/12] selftests/bpf: Add inline-asm tests for by-value arguments Yonghong Song
2026-09-09 7:30 ` bot+bpf-ci
2026-09-11 5:37 ` Yonghong Song
2026-09-09 6:26 ` [PATCH bpf-next v2 12/12] selftests/bpf: Add tests for by-value kfunc arguments Yonghong Song
2026-09-09 7:30 ` bot+bpf-ci
2026-09-11 5:57 ` Yonghong Song
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