From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 990A52566D6 for ; Mon, 24 Feb 2025 10:42:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740393726; cv=none; b=PuoZvzt4H/JWwmKjbd4N5/nG9gPbyBwLXJlCmjf/TuSWRhxRRASyXMsP2DnY4eel5tXIflLjdefHF7guYm13xYb2kQ1k4U+IdJp2rbfwHXE5MrMqmBC0AMd/aMOaAEyZlTeHFVz7pyJp8Nf7g41kRM35xNRfGCpXLJvqznENQnA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740393726; c=relaxed/simple; bh=BswoIa2CEjiPwVoiLWCceNxnjLsje5paS+wRhqcTiOs=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=C1KeNa7oM2oUqtGdddKfh9xaQ7ECjbEvK3O4DY2wt55mLejyp3jTjZkhXAg/hxtPrzecr1dctwJ5Vh+2QnnHmuA/aZbma8bbP0IXAVJmmbeuLMB17o4YJ2TrE+cjyC64bMuM+9Wk6ybDog/HUPju3M9Yhrna1Do7SmWNEEtTGAA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Xsh6IoCE; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Xsh6IoCE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E337DC4CEE6; Mon, 24 Feb 2025 10:42:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740393725; bh=BswoIa2CEjiPwVoiLWCceNxnjLsje5paS+wRhqcTiOs=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=Xsh6IoCE0sYt9h3ZUD+NRMbBBSlW3grsDeSc6VS5ZhfdkdX/lnz2htNM0di9gFHXJ aGe5NB47s2syN5FmS93WvNiSgfYVe4es52+TJ7+gdW99NtMU0s3jT94Cbridl1KJE2 YsYwquyS5sKqDG4DMyFqaaN51xFS9Ge9tpLQ+MeGxM/haxTcfQtjCWpwu2bOpTFIa3 xunUnilHm+oHK++K+cxnFFpLPZNPTbVZXwAHyd3ATknwIPfF7WfnqNdGS7IbNRVznx P7pgJV0jfrD8jfp29FaGq8CeW9X82+QtIKqVbc92Hsae+QpLvvWq0aHTDImcavlHch rVuGsyNuFLu5w== Message-ID: Subject: Re: [PATCH mptcp-next v1 5/6] sock: add sock_kmemdup helper From: Geliang Tang To: Matthieu Baerts , mptcp@lists.linux.dev Cc: Geliang Tang Date: Mon, 24 Feb 2025 18:42:01 +0800 In-Reply-To: References: <0a3f7a31983f0587ace333f349f3e630c49d075d.1740384564.git.tanggeliang@kylinos.cn> Autocrypt: addr=geliang@kernel.org; prefer-encrypt=mutual; keydata=mQINBGWKTg4BEAC/Subk93zbjSYPahLCGMgjylhY/s/R2ebALGJFp13MPZ9qWlbVC8O+X lU/4reZtYKQ715MWe5CwJGPyTACILENuXY0FyVyjp/jl2u6XYnpuhw1ugHMLNJ5vbuwkc1I29nNe8 wwjyafN5RQV0AXhKdvofSIryqm0GIHIH/+4bTSh5aB6mvsrjUusB5MnNYU4oDv2L8MBJStqPAQRLl P9BWcKKA7T9SrlgAr0VsFLIOkKOQPVTCnYxn7gfKogH52nkPAFqNofVB6AVWBpr0RTY7OnXRBMInM HcjVG4I/NFn8Cc7oaGaWHqX/yHAufJKUsldieQVFd7C/SI8jCUXdkZxR0Tkp0EUzkRc/TS1VwWHav 0x3oLSy/LGHfRaIC/MqdGVqgCnm6wapUt7f/JHloyIyKJBGBuHCLMpN6n/kNkSCzyZKV7h6Vw1OL5 18p0U3Optyakoh95KiJsKzcd3At/eftQGlNn5WDflHV1+oMdW2sRgfVDPrYeEcYI5IkTc3LRO6ucp VCm9/+poZSHSXMI/oJ6iXMJE8k3/aQz+EEjvc2z0p9aASJPzx0XTTC4lciTvGj62z62rGUlmEIvU2 3wWH37K2EBNoq+4Y0AZsSvMzM+CcTo25hgPaju1/A8ErZsLhP7IyFT17ARj/Et0G46JRsbdlVJ/Pv X+XIOc2mpqx/QARAQABtCVHZWxpYW5nIFRhbmcgPGdlbGlhbmcudGFuZ0BsaW51eC5kZXY+iQJUBB MBCgA+FiEEZiKd+VhdGdcosBcafnvtNTGKqCkFAmWKTg4CGwMFCRLMAwAFCwkIBwIGFQoJCAsCBBY CAwECHgECF4AACgkQfnvtNTGKqCmS+A/9Fec0xGLcrHlpCooiCnNH0RsXOVPsXRp2xQiaOV4vMsvh G5AHaQLb3v0cUr5JpfzMzNpEkaBQ/Y8Oj5hFOORhTyCZD8tY1aROs8WvbxqvbGXHnyVwqy7AdWelP +0lC0DZW0kPQLeel8XvLnm9Wm3syZgRGxiM/J7PqVcjujUb6SlwfcE3b2opvsHW9AkBNK7v8wGIcm BA3pS1O0/anP/xD5s5L7LIMADVB9MqQdeLdFU+FFdafmKSmcP9A2qKHAvPBUuQo3xoBOZR3DMqXIP kNCBfQGkAx5tm1XYli1u3r5tp5QCRbY5LSkntMNJJh0eWLU8I+zF6NWhqNhHYRD3zc1tiXlG5E0ob pX02Dy25SE2zB3abCRdAK30nCI4lMyMCcyaeFqvf6uhiugLiuEPRRRdJDWICOLw6KOFmxWmue1F71 k08nj5PQMWQUX3X2K6jiOuoodYwnie/9NsH3DBHIVzVPWASFd6JkZ21i9Ng4ie+iQAveRTCeCCF6V RORJR0R8d7mI9+1eqhNeKzs21gQPVf/KBEIpwPFDjOdTwS/AEQQyhB+5ALeYpNgfKl2p30C20VRfJ GBaTc4ReUXh9xbUx5OliV69iq9nIVIyculTUsbrZX81Gz6UlbuSzWc4JclWtXf8/QcOK31wputde7 Fl1BTSR4eWJcbE5Iz2yzgQu0IUdlbGlhbmcgVGFuZyA8Z2VsaWFuZ0BrZXJuZWwub3JnPokCVAQTA QoAPhYhBGYinflYXRnXKLAXGn577TUxiqgpBQJlqclXAhsDBQkSzAMABQsJCAcCBhUKCQgLAgQWAg MBAh4BAheAAAoJEH577TUxiqgpaGkP/3+VDnbu3HhZvQJYw9a5Ob/+z7WfX4lCMjUvVz6AAiM2atD yyUoDIv0fkDDUKvqoU9BLU93oiPjVzaR48a1/LZ+RBE2mzPhZF201267XLMFBylb4dyQZxqbAsEhV c9VdjXd4pHYiRTSAUqKqyamh/geIIpJz/cCcDLvX4sM/Zjwt/iQdvCJ2eBzunMfouzryFwLGcOXzx OwZRMOBgVuXrjGVB52kYu1+K90DtclewEgvzWmS9d057CJztJZMXzvHfFAQMgJC7DX4paYt49pNvh cqLKMGNLPsX06OR4G+4ai0JTTzIlwVJXuo+uZRFQyuOaSmlSjEsiQ/WsGdhILldV35RiFKe/ojQNd 4B4zREBe3xT+Sf5keyAmO/TG14tIOCoGJarkGImGgYltTTTM6rIk/wwo9FWshgKAmQyEEiSzHTSnX cGbalD3Do89YRmdG+5eP7HQfsG+VWdn8IH6qgIvSt8GOw6RfSP7omMXvXji1VrbWG4LOFYcsKTN+d GDhl8LmU0y44HejkCzYj/b28MvNTiRVfucrmZMGgI8L5A4ZwQ3Inv7jY13GZSvTb7PQIbqMcb1P3S qWJFodSwBg9oSw21b+T3aYG3z3MRCDXDlZAJONELx32rPMdBva8k+8L+K8gc7uNVH4jkMPkP9jPnV Px+2P2cKc7LXXedb/qQ3M Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.52.3-0ubuntu1 Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi Matt, Thanks for the review. On Mon, 2025-02-24 at 09:54 +0100, Matthieu Baerts wrote: > Hi Geliang, > > On 24/02/2025 09:13, Geliang Tang wrote: > > From: Geliang Tang > > > > This patch adds the sock version of kmemdup() helper, named > > sock_kmemdup(), > > to duplicate a memory block using the socket's option memory > > buffer. > > > > Signed-off-by: Geliang Tang > > --- > >  include/net/sock.h |  1 + > >  net/core/sock.c    | 23 +++++++++++++++++++++++ > >  2 files changed, 24 insertions(+) > > > > diff --git a/include/net/sock.h b/include/net/sock.h > > index edbb870e3f86..ffd757e7e329 100644 > > --- a/include/net/sock.h > > +++ b/include/net/sock.h > > @@ -1793,6 +1793,7 @@ static inline struct sk_buff > > *sock_alloc_send_skb(struct sock *sk, > >  } > >   > >  void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); > > +void *sock_kmemdup(struct sock *sk, const void *src, int size, > > gfp_t priority); > >  void sock_kfree_s(struct sock *sk, void *mem, int size); > >  void sock_kzfree_s(struct sock *sk, void *mem, int size); > >  void sk_send_sigurg(struct sock *sk); > > diff --git a/net/core/sock.c b/net/core/sock.c > > index 0d385bf27b38..d09bd697c120 100644 > > --- a/net/core/sock.c > > +++ b/net/core/sock.c > > @@ -2805,6 +2805,29 @@ void *sock_kmalloc(struct sock *sk, int > > size, gfp_t priority) > >  } > >  EXPORT_SYMBOL(sock_kmalloc); > >   > > +/* > > + * Duplicate a memory block using the socket's option memory > > buffer. > > + */ > > +void *sock_kmemdup(struct sock *sk, const void *src, int size, > > gfp_t priority) > > +{ > > + int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max); > > + > > + if ((unsigned int)size <= optmem_max && > > +     atomic_read(&sk->sk_omem_alloc) + size < optmem_max) { > > + void *mem; > > + /* First do the add, to avoid the race if kmalloc > > + * might sleep. > > + */ > > + atomic_add(size, &sk->sk_omem_alloc); > > + mem = kmemdup(src, size, priority); I made some updates to this patch here. mem = src ? kmemdup(src, size, priority) : kmalloc(size, priority); > > + if (mem) > > + return mem; > > + atomic_sub(size, &sk->sk_omem_alloc); Then sock_kmalloc() can be implemented through sock_kmemdup(), which can reduce the duplication of code between them. void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) { return sock_kmemdup(sk, NULL, size, priority); } > > I'm not really convinced by this helper: it is a duplication of > sock_kmalloc(), and it is only used once in MPTCP code. I found that this new helper can also be used in mptcp_copy_ip_options() too. > > Calling sock_kmalloc() + memset, and using this new helper in > different > places in the net code might help. But still, I don't know if this And there are three other places in the net code where it can be used: ipv6_dup_options() sctp_v4_copy_ip_options() tcp_ao_copy_key() That way, this helper can be used in five places. > would > be accepted, it is only saving one line (plus memcpy() will be used > when > it is not needed, same for the previous patch at the end). What do you think of this new version? > > If you still want to propose that, I suggest sending a dedicated > series > to netdev, not to block MPTCP (only) patches. WDYT? Please remove the last two patches from this set if others are ready to apply. Thanks, -Geliang > > Cheers, > Matt