From patchwork Tue Jan 7 08:55:54 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 13928454 X-Patchwork-Delegate: bpf@iogearbox.net Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B83211E0B91; Tue, 7 Jan 2025 08:43:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736239441; cv=none; b=jIB9eWB/QaJmk2BIpf8r/Tj1x2rCQaV85+z+nM0xhIz2dJQZgnHsZAVEnRI7m/zSw5hxjHkIlgwodhe1NbD6ogyVp+wHObBqvvVxlv9xRLmYn2LMEw+ph0kWk3TLaBXMnSJvK3xyBGIwO+AsAVDferg0nVM0X/5G/zSCkAZFTCw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736239441; c=relaxed/simple; bh=YIRIy6EIg2ShCQZ2Aqk/7mvJenquahz9NqZBD/YsqfI=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=bjDvnJVQSEprg/hzRXq9CDDWmAxGMU2ePpZtjz66Am7uDh1TK290KWRfpv2k39SZYSIhQFQyw1++cyRqIxq9WKZG8iXRJDF8W3bk2kbOy29QGxYS7nxFczd+oXNlVMzGsM8nez9KOvGepN7zTwOBGspWqwyyOJMhjmqo2j9Hktg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4YS4MV1Jc1z4f3jXw; Tue, 7 Jan 2025 16:43:34 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 5000E1A0E33; Tue, 7 Jan 2025 16:43:54 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.124.27]) by APP4 (Coremail) with SMTP id gCh0CgC3Gl9E6XxnpFgeAQ--.43336S6; Tue, 07 Jan 2025 16:43:54 +0800 (CST) From: Hou Tao To: bpf@vger.kernel.org, netdev@vger.kernel.org Cc: Martin KaFai Lau , Alexei Starovoitov , Andrii Nakryiko , Eduard Zingerman , Song Liu , Hao Luo , Yonghong Song , Daniel Borkmann , KP Singh , Stanislav Fomichev , Jiri Olsa , John Fastabend , Sebastian Andrzej Siewior , houtao1@huawei.com, xukuohai@huawei.com Subject: [PATCH bpf-next 2/7] bpf: Bail out early in __htab_map_lookup_and_delete_elem() Date: Tue, 7 Jan 2025 16:55:54 +0800 Message-Id: <20250107085559.3081563-3-houtao@huaweicloud.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20250107085559.3081563-1-houtao@huaweicloud.com> References: <20250107085559.3081563-1-houtao@huaweicloud.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: gCh0CgC3Gl9E6XxnpFgeAQ--.43336S6 X-Coremail-Antispam: 1UD129KBjvJXoW7ZFW5tw1rXry8tw1fGw1xKrg_yoW5JFyrpF Z3Kry7Wry8ursIqa4ftw1jka95J340qw48Ka4DJFyrCF13Zryvqw13AF93GFy3Gr92yr4r trs2qF1fK3y2vrDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUP2b4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUXw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v2 6rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMc Ij6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_ Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1lc7CjxVAaw2AFwI 0_GFv_Wryl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG 67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r4a6rW5MI IYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E 14v26F4j6r4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr 0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU0I3 85UUUUU== X-CM-SenderInfo: xkrx3t3r6k3tpzhluzxrxghudrp/ X-Patchwork-Delegate: bpf@iogearbox.net From: Hou Tao Use goto statement to bail out early when the target element is not found, instead of using a large else branch to handle the more likely case. This change doesn't affect functionality and simply make the code cleaner. Signed-off-by: Hou Tao --- kernel/bpf/hashtab.c | 51 ++++++++++++++++++++++---------------------- 1 file changed, 26 insertions(+), 25 deletions(-) diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 8fecf21c132a..59eb117908c5 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -1641,37 +1641,38 @@ static int __htab_map_lookup_and_delete_elem(struct bpf_map *map, void *key, l = lookup_elem_raw(head, hash, key, key_size); if (!l) { ret = -ENOENT; - } else { - if (is_percpu) { - u32 roundup_value_size = round_up(map->value_size, 8); - void __percpu *pptr; - int off = 0, cpu; + goto out_unlock; + } - pptr = htab_elem_get_ptr(l, key_size); - for_each_possible_cpu(cpu) { - copy_map_value_long(&htab->map, value + off, per_cpu_ptr(pptr, cpu)); - check_and_init_map_value(&htab->map, value + off); - off += roundup_value_size; - } - } else { - u32 roundup_key_size = round_up(map->key_size, 8); + if (is_percpu) { + u32 roundup_value_size = round_up(map->value_size, 8); + void __percpu *pptr; + int off = 0, cpu; - if (flags & BPF_F_LOCK) - copy_map_value_locked(map, value, l->key + - roundup_key_size, - true); - else - copy_map_value(map, value, l->key + - roundup_key_size); - /* Zeroing special fields in the temp buffer */ - check_and_init_map_value(map, value); + pptr = htab_elem_get_ptr(l, key_size); + for_each_possible_cpu(cpu) { + copy_map_value_long(&htab->map, value + off, per_cpu_ptr(pptr, cpu)); + check_and_init_map_value(&htab->map, value + off); + off += roundup_value_size; } + } else { + u32 roundup_key_size = round_up(map->key_size, 8); - hlist_nulls_del_rcu(&l->hash_node); - if (!is_lru_map) - free_htab_elem(htab, l); + if (flags & BPF_F_LOCK) + copy_map_value_locked(map, value, l->key + + roundup_key_size, + true); + else + copy_map_value(map, value, l->key + + roundup_key_size); + /* Zeroing special fields in the temp buffer */ + check_and_init_map_value(map, value); } + hlist_nulls_del_rcu(&l->hash_node); + if (!is_lru_map) + free_htab_elem(htab, l); +out_unlock: htab_unlock_bucket(htab, b, hash, bflags); if (is_lru_map && l)