From patchwork Sat Mar 1 19:13:15 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 13997659 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mail-ua1-f73.google.com (mail-ua1-f73.google.com [209.85.222.73]) (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 B1E3E1DF965 for ; Sat, 1 Mar 2025 19:13:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740856404; cv=none; b=SMNEthGwQUNtEAiCkyMsckuRysPS9waInhyoyeMmBZgRrZzTVWPSbZokaybFQhYsckQUFEW0WmO99bmK79WNZhmgBb6dMxRaJXGkEZClGSBP78APNk8yBuYPZSOwkGb2D+IgmKyCA/RbquUnJLW36JQHnL57cFhNMNBahn0/fls= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740856404; c=relaxed/simple; bh=Im/2Im03GoGhqx+/PqYukGkdBPKW+8GScD1PdDoOg4c=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=Yzhw9KlJbPphRw/DKN74Jk7H8b2473+/nnKskxmBn6iGJNkGnjV9kM7UDZu4odGypIP4G2HjT+vrKOxTpU2xUk364HKOvpa5WBj2vCW11FFqLK0RUkfg2wTDQz8dEzLRMcqQ78NA4CXWYj0/oNcs2cXTa9LVO83UGxJCV3LYx3c= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Bd5uztdZ; arc=none smtp.client-ip=209.85.222.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Bd5uztdZ" Received: by mail-ua1-f73.google.com with SMTP id a1e0cc1a2514c-86b35aeaaf3so4035094241.3 for ; Sat, 01 Mar 2025 11:13:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1740856401; x=1741461201; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=9ywVjhY6fzV+QfKdVlcvS+RJwruHcsdpVLrrrMqKp3I=; b=Bd5uztdZjScOoRWA9E/KgIi3FjaKTRaCIOVSWCLR5V5teCk86vAW3Kr0EKHrJj+RGF yrc2fZvTmgqw8mRb5Ve5lyYpXh6odM4/v6pmbobCQaUXzYX6sVPBZPXEylovIpjG0BRh IHCQuolwFDjKPc0whkoH2N13yCmxXyHCc95KxoKELV8c7174t2a4cpVurPOZVrIB+Yc1 1anAQ4AcZB3xRHBEaMvw0e7lM58Sv2ncOALGnGV/2A6j7vp5Z7LSMYJsH6/xNe4JEN56 uKtwRPsJxW9gh3aztFjW7lff5912d2sHJWN5AqhlQXydgIpzWqJPw8BpMY6O1PkUozKa wZMg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740856401; x=1741461201; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=9ywVjhY6fzV+QfKdVlcvS+RJwruHcsdpVLrrrMqKp3I=; b=T/Fl4D2dlkUgYGTQEE6HCW4PfE7VYEcNFQbpWkF3hIH9BSGMNuAzH4leYWwyWxch2c /JUPijqBWEXfxGsBsQhYwDnpr5klh1VoxhRTZ7bkreSq94hkGU09uSP310p29pRhDQob RVg6ZYXxemam0Dvi9PwsFU+GL2eQfOxvouE9TqEbV7J+070yUE7UPNA8RfIP706qaVYW +c05PqtukynAKV046LjUk0AOftBlaFtaQBbRkVL7ii1sM0ot8emddx69LqFzhdehGwLJ WTCLXg7FWTijtQyojGAddlyPp8vdk4gtsluwSIaDQuL4lFsdUxOvYTDdZoLWQ7kIBnLW B65Q== X-Forwarded-Encrypted: i=1; AJvYcCVjnk+4yCjeGeeuyTIM3DEVRDHXC2QWWzDRNgbugki51fg4VHzkQaZDp6WCfm7YBjORnnI=@vger.kernel.org X-Gm-Message-State: AOJu0Yyw/wqFCAOXK6x5M5EuaoJXQHhoG7cJCI1dZWOpcnzmGy7q7xIm mQUql4+HmfFqJNSzTDakiYc5WWk4fLEXK7+jOZKLM5rMeTCB4HL1yRw0zgNG7uiLd/YtblaGEBF pDUomnfbWrg== X-Google-Smtp-Source: AGHT+IHlEDY1w99nPU00fv2hKwIDN+zsB15ccWmux6lcYZLwxn41ycgj1n8xqVL27f9ejrkUf8ENXcghURVc0Q== X-Received: from vsbjj2.prod.google.com ([2002:a05:6102:18c2:b0:4c1:6c89:f6c8]) (user=edumazet job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6102:292b:b0:4bb:e8c5:b157 with SMTP id ada2fe7eead31-4c044ef98d0mr5666933137.25.1740856401483; Sat, 01 Mar 2025 11:13:21 -0800 (PST) Date: Sat, 1 Mar 2025 19:13:15 +0000 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.48.1.711.g2feabab25a-goog Message-ID: <20250301191315.1532629-1-edumazet@google.com> Subject: [PATCH bpf-next] bpf: no longer acquire map_idr_lock in bpf_map_inc_not_zero() From: Eric Dumazet To: Alexei Starovoitov , Daniel Borkmann , John Fastabend Cc: Stanislav Fomichev , netdev@vger.kernel.org, bpf@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet , Kui-Feng Lee , Martin KaFai Lau X-Patchwork-Delegate: bpf@iogearbox.net bpf_sk_storage_clone() is the only caller of bpf_map_inc_not_zero() and is holding rcu_read_lock(). map_idr_lock does not add any protection, just remove the cost for passive TCP flows. Signed-off-by: Eric Dumazet Cc: Kui-Feng Lee Cc: Martin KaFai Lau Acked-by: Stanislav Fomichev --- kernel/bpf/syscall.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index e1e42e918ba7f682223e9a78028bb0cc360c01ce..d68c8d61f7ceddb732a5646c00b8f0c71fdc2d71 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1593,11 +1593,8 @@ struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref) struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map) { - spin_lock_bh(&map_idr_lock); - map = __bpf_map_inc_not_zero(map, false); - spin_unlock_bh(&map_idr_lock); - - return map; + lockdep_assert(rcu_read_lock_held()); + return __bpf_map_inc_not_zero(map, false); } EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);