From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f174.google.com (mail-pf1-f174.google.com [209.85.210.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E054231AF24 for ; Wed, 26 Nov 2025 08:50:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764147054; cv=none; b=fQRfUdxfwPdvdMSDXCzvj75VUG2ybwaUDycJQPe7jEFy3Y1bWCLwmV+M7407dp4pBWU6ZzosU+2Z8CB72lAH1boVJyFuF1pOZB4MsX4QfaCdTgWNK//tysala96tpHy9DMBQFdgMKLeEuH6Apo6fqPnDKasaM1923GXsdpn23C4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764147054; c=relaxed/simple; bh=0kgEQtgvPa55pKXFrtj7srWoStjEyAoMQzDyIdaQ2pI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=JbVs2Kmpvlb0td6a5iuxAuCzl4z/0f/9z31Rha52G1vYtHEYtR+3sJJyyRdjg6Sz7An0SM7u/yGV9nMaa0JjVwGYDQHqXJ4UlOUJhJjdv5PIpAXziRQe1rpgqknyx5iD4DrM4IvHLvx8pvxgtSqwTQDWbeQG8BPrOKC2h23OAQ8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=DyW+p2ev; arc=none smtp.client-ip=209.85.210.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="DyW+p2ev" Received: by mail-pf1-f174.google.com with SMTP id d2e1a72fcca58-7b8eff36e3bso10064998b3a.2 for ; Wed, 26 Nov 2025 00:50:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1764147052; x=1764751852; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=mgDV1ROzgzpe5gCmmSbOnsLIyQpLC/h36ENHoKlfvVE=; b=DyW+p2evw6yBS3tsjQXxaAzDW1Y1+Lnmth8Lk2r6jrfyEkemBv33aCKMDu/xkR1vQ+ Xd6aAlZZDD3f+wHiykwxpjzSpfdAQ0IrSctL/B0ehyvK8qYXsLV1l7kt2KboW8pihr1i 5VMAfdBjxBteYHqnFLbd0WTapseNl2+0/D94EXTq08hKJx0wlnzS/a6SmXDoa4JEsCh0 fdoXYYflgWW8kdm6yJsOl4+NwKP2Ih50qLpkejl+gnjnLAC4sVtvR5URyluu20cEGM0w Dl6El4aeJ0PLcmOMKAUTAwOo/ZORychQLV4isyLP32wfTQprmY63/l24neoNNXsqcSVb lNgQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1764147052; x=1764751852; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=mgDV1ROzgzpe5gCmmSbOnsLIyQpLC/h36ENHoKlfvVE=; b=EYANViAoN1VGJcalaIMRHwOydav8jjPguJaEnXTshl9ZdyWrwDD6yZR42UFpT93nNY WsH3g2Lcgv9qK5/N/4IYpqwuro33bm/NdwpVMQPgJowQX+uLS3+WOjVSuuC8iYzYCUtX UG3pbs0wg6V53fN95vL1EWvCainJAZgjLl25mVsUCT7n1p+nOB4+lxlXYnQWeDIQI5Vr PYK+P2GndZN+0TAqHlmWcnZ1W4J607B50FaKOCqnhAOtoq3Cb8bd1nC+6kaTv3+wHx+T LgK5cWslUnU8Ldie0P4vc3l8uE2kuzUF133wHf7rXfgv91e77jK+J7Rp5LoqV4SuD1c9 qRIg== X-Forwarded-Encrypted: i=1; AJvYcCXuQvFJaNAkclS53oCYAlFHGK5iHvEZkFFaJ50CX+ZrmMaYQzsbIr0FrP0/5vFjnUrnzms=@vger.kernel.org X-Gm-Message-State: AOJu0YwHeu8GyLzbds/Jbj+dBJlD1NIL+VjXBvmqvg+RRXoylh7ZTR7W kFwqG2F2uXZi2db0L5/RnCA1C5VbjWWSL3GAl8uhV1vvihpcv6WmXTdE X-Gm-Gg: ASbGncs3aPsLrvLq+p/MQhok/uT4TjA6Rhr3I0FGuJb9iqk9eNelt0KrDK9OAVYxec5 sUKGHlXzaGMUI9jO9wALws7JcLu83+XxLeb1UOl0mbhqxdHkrlK9zpx2IW3rs03lQFCmULlt3pc pr+rbRpDq5owXqEiGEPvqmq5RpuBC/21DmyKTYAgXMt2rwF2JAe291sjGnCrXTCUfIhhHifnBRQ JdR0IyPjZCQIA6dWN3WtCL7z9bcArtsVkanXad27COzHDB9FIF0NG471N6z18zpqg8xOpLS37VI qe18cyjdxzLpbOpmogoLmtzQJy3c0plU6e+wbnFD+UrVMcYwAG+e6jrhCmdb1XwMM9i1VJ1ezKq wMcCOpEukzKIT7JbFUfnR6WldD21drF2SLNok6xPYOkcBNCfKaZq7a7mGQWHQNiJQ4qcWIJN39a 8yeN4Kd3KM9euJ0QYoV65PITk5Ov0= X-Google-Smtp-Source: AGHT+IFs6pLfGprWWWpfV4uPUwFHD5qyL94NbyLWxHqsqV9ucC0hIrcGzqA9thasWaM1KDvECSl8tQ== X-Received: by 2002:a05:6a20:430b:b0:341:c4e5:f626 with SMTP id adf61e73a8af0-3637db254efmr6304165637.7.1764147052098; Wed, 26 Nov 2025 00:50:52 -0800 (PST) Received: from pengdl-pc.mioffice.cn ([43.224.245.249]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-7c3f023fd82sm20885721b3a.42.2025.11.26.00.50.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 26 Nov 2025 00:50:51 -0800 (PST) From: Donglin Peng To: ast@kernel.org, andrii.nakryiko@gmail.com Cc: eddyz87@gmail.com, zhangxiaoqin@xiaomi.com, ihor.solodrai@linux.dev, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, pengdonglin , Alan Maguire Subject: [RFC bpf-next v8 6/9] btf: Optimize type lookup with binary search Date: Wed, 26 Nov 2025 16:50:22 +0800 Message-Id: <20251126085025.784288-7-dolinux.peng@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20251126085025.784288-1-dolinux.peng@gmail.com> References: <20251126085025.784288-1-dolinux.peng@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: pengdonglin Improve btf_find_by_name_kind() performance by adding binary search support for sorted types. Falls back to linear search for compatibility. Cc: Eduard Zingerman Cc: Alexei Starovoitov Cc: Andrii Nakryiko Cc: Alan Maguire Cc: Ihor Solodrai Cc: Xiaoqin Zhang Signed-off-by: pengdonglin --- kernel/bpf/btf.c | 85 +++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 76 insertions(+), 9 deletions(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 0de8fc8a0e0b..842f9c0200e4 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -259,6 +259,7 @@ struct btf { void *nohdr_data; struct btf_header hdr; u32 nr_types; /* includes VOID for base BTF */ + u32 sorted_start_id; u32 types_size; u32 data_size; refcount_t refcnt; @@ -494,6 +495,11 @@ static bool btf_type_is_modifier(const struct btf_type *t) return false; } +static int btf_start_id(const struct btf *btf) +{ + return btf->start_id + (btf->base_btf ? 0 : 1); +} + bool btf_type_is_void(const struct btf_type *t) { return t == &btf_void; @@ -544,21 +550,79 @@ u32 btf_nr_types(const struct btf *btf) return total; } +static s32 btf_find_by_name_bsearch(const struct btf *btf, const char *name, + s32 start_id, s32 end_id) +{ + const struct btf_type *t; + const char *tname; + s32 l, r, m, lmost = -ENOENT; + int ret; + + l = start_id; + r = end_id; + while (l <= r) { + m = l + (r - l) / 2; + t = btf_type_by_id(btf, m); + tname = btf_name_by_offset(btf, t->name_off); + ret = strcmp(tname, name); + if (ret < 0) { + l = m + 1; + } else { + if (ret == 0) + lmost = m; + r = m - 1; + } + } + + return lmost; +} + s32 btf_find_by_name_kind(const struct btf *btf, const char *name, u8 kind) { + const struct btf *base_btf = btf_base_btf(btf); const struct btf_type *t; const char *tname; - u32 i, total; + s32 idx; - total = btf_nr_types(btf); - for (i = 1; i < total; i++) { - t = btf_type_by_id(btf, i); - if (BTF_INFO_KIND(t->info) != kind) - continue; + if (base_btf) { + idx = btf_find_by_name_kind(base_btf, name, kind); + if (idx > 0) + return idx; + } - tname = btf_name_by_offset(btf, t->name_off); - if (!strcmp(tname, name)) - return i; + if (btf->sorted_start_id > 0) { + /* skip anonymous types */ + s32 start_id = btf->sorted_start_id; + s32 end_id = btf_nr_types(btf) - 1; + + idx = btf_find_by_name_bsearch(btf, name, start_id, end_id); + if (idx < 0) + return -ENOENT; + + t = btf_type_by_id(btf, idx); + if (BTF_INFO_KIND(t->info) == kind) + return idx; + + for (idx++; idx <= end_id; idx++) { + t = btf_type_by_id(btf, idx); + tname = btf_name_by_offset(btf, t->name_off); + if (strcmp(tname, name) != 0) + return -ENOENT; + if (BTF_INFO_KIND(t->info) == kind) + return idx; + } + } else { + u32 i, total; + + total = btf_nr_types(btf); + for (i = btf_start_id(btf); i < total; i++) { + t = btf_type_by_id(btf, i); + if (BTF_INFO_KIND(t->info) != kind) + continue; + tname = btf_name_by_offset(btf, t->name_off); + if (strcmp(tname, name) == 0) + return i; + } } return -ENOENT; @@ -5791,6 +5855,7 @@ static struct btf *btf_parse(const union bpf_attr *attr, bpfptr_t uattr, u32 uat goto errout; } env->btf = btf; + btf->sorted_start_id = 0; data = kvmalloc(attr->btf_size, GFP_KERNEL | __GFP_NOWARN); if (!data) { @@ -6210,6 +6275,7 @@ static struct btf *btf_parse_base(struct btf_verifier_env *env, const char *name btf->data = data; btf->data_size = data_size; btf->kernel_btf = true; + btf->sorted_start_id = 0; snprintf(btf->name, sizeof(btf->name), "%s", name); err = btf_parse_hdr(env); @@ -6327,6 +6393,7 @@ static struct btf *btf_parse_module(const char *module_name, const void *data, btf->start_id = base_btf->nr_types; btf->start_str_off = base_btf->hdr.str_len; btf->kernel_btf = true; + btf->sorted_start_id = 0; snprintf(btf->name, sizeof(btf->name), "%s", module_name); btf->data = kvmemdup(data, data_size, GFP_KERNEL | __GFP_NOWARN); -- 2.34.1