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 5D4C1360312; Mon, 5 May 2025 22:45:40 +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=1746485142; cv=none; b=YsEwg4zJoEzetbXTNEarxqRZ1u5UshDAl6/+mVe8jTqYE09kPwnepJYHJXpGmNxEItT52JECGYmzZcTrZGgAkOQy9MpVhIRBbPWW2JzcpsgBXXTqFl2BIT2q49JidSGkedG/UunErmHBy7kwbDXgbQqjs0xPBYtCzHmlcWme3Rs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746485142; c=relaxed/simple; bh=NnPnudEG8u4eNUBGCuS+YBI+NjHx/MT7Hlssv4Gji0I=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=OUdsy5cCVSLatNEZ3S2gzGX5iaXOSI+8QxfGQqEBFkrv0FldcnFa4us1qq3xFdLC4Omj6LiUNEEbDvT3D67DYLEj+OmK994enEOijJRan5nH1pGJ7GjPm5EKxw70CoGcWEVB4N5zyqzCBvkcBNGHTtz0O3t5bQAbxVMIIAvf4gw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=c3U0vcrk; 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="c3U0vcrk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B4A0C4CEEF; Mon, 5 May 2025 22:45:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746485140; bh=NnPnudEG8u4eNUBGCuS+YBI+NjHx/MT7Hlssv4Gji0I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=c3U0vcrktIyzDYXLCB8E8y6tLmcmoTfPCgEDgA7w04lALxRLrZW4uWl6W2ZBdcs/y JS1TDN4NC14v0VikavDFAlLEHgv9muSG80ky92LBt78ex6KH3bCdPBV/vt309L2CZ7 QwyTIcRbAUc2e0s3/GxOpqneq6JGhO1qFR2ZzNInzN2X9UpnwWlJuBWj05Pii0MarM hU9fm2ilODB+eYXC5mfOfkXzOAL90l6EkW9NF9XqWmFO9etdwJMpCnXrCzx1ZfJzel JHXytl6wW1dtCv1L2NZQcv/UQ460SCG/hp/bV+0GSnWJkROvruQXHzIt/mvskuTlaK gv9KA1/GFuwuQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , Jason Xing , Kuniyuki Iwashima , Jakub Kicinski , Sasha Levin , ncardwell@google.com, davem@davemloft.net, dsahern@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 6.12 180/486] tcp: bring back NUMA dispersion in inet_ehash_locks_alloc() Date: Mon, 5 May 2025 18:34:16 -0400 Message-Id: <20250505223922.2682012-180-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505223922.2682012-1-sashal@kernel.org> References: <20250505223922.2682012-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.12.26 Content-Transfer-Encoding: 8bit From: Eric Dumazet [ Upstream commit f8ece40786c9342249aa0a1b55e148ee23b2a746 ] We have platforms with 6 NUMA nodes and 480 cpus. inet_ehash_locks_alloc() currently allocates a single 64KB page to hold all ehash spinlocks. This adds more pressure on a single node. Change inet_ehash_locks_alloc() to use vmalloc() to spread the spinlocks on all online nodes, driven by NUMA policies. At boot time, NUMA policy is interleave=all, meaning that tcp_hashinfo.ehash_locks gets hash dispersion on all nodes. Tested: lack5:~# grep inet_ehash_locks_alloc /proc/vmallocinfo 0x00000000d9aec4d1-0x00000000a828b652 69632 inet_ehash_locks_alloc+0x90/0x100 pages=16 vmalloc N0=2 N1=3 N2=3 N3=3 N4=3 N5=2 lack5:~# echo 8192 >/proc/sys/net/ipv4/tcp_child_ehash_entries lack5:~# numactl --interleave=all unshare -n bash -c "grep inet_ehash_locks_alloc /proc/vmallocinfo" 0x000000004e99d30c-0x00000000763f3279 36864 inet_ehash_locks_alloc+0x90/0x100 pages=8 vmalloc N0=1 N1=2 N2=2 N3=1 N4=1 N5=1 0x00000000d9aec4d1-0x00000000a828b652 69632 inet_ehash_locks_alloc+0x90/0x100 pages=16 vmalloc N0=2 N1=3 N2=3 N3=3 N4=3 N5=2 lack5:~# numactl --interleave=0,5 unshare -n bash -c "grep inet_ehash_locks_alloc /proc/vmallocinfo" 0x00000000fd73a33e-0x0000000004b9a177 36864 inet_ehash_locks_alloc+0x90/0x100 pages=8 vmalloc N0=4 N5=4 0x00000000d9aec4d1-0x00000000a828b652 69632 inet_ehash_locks_alloc+0x90/0x100 pages=16 vmalloc N0=2 N1=3 N2=3 N3=3 N4=3 N5=2 lack5:~# echo 1024 >/proc/sys/net/ipv4/tcp_child_ehash_entries lack5:~# numactl --interleave=all unshare -n bash -c "grep inet_ehash_locks_alloc /proc/vmallocinfo" 0x00000000db07d7a2-0x00000000ad697d29 8192 inet_ehash_locks_alloc+0x90/0x100 pages=1 vmalloc N2=1 0x00000000d9aec4d1-0x00000000a828b652 69632 inet_ehash_locks_alloc+0x90/0x100 pages=16 vmalloc N0=2 N1=3 N2=3 N3=3 N4=3 N5=2 Signed-off-by: Eric Dumazet Tested-by: Jason Xing Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250305130550.1865988-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/inet_hashtables.c | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index 9bfcfd016e182..2b4a588247639 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -1230,22 +1230,37 @@ int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo) { unsigned int locksz = sizeof(spinlock_t); unsigned int i, nblocks = 1; + spinlock_t *ptr = NULL; - if (locksz != 0) { - /* allocate 2 cache lines or at least one spinlock per cpu */ - nblocks = max(2U * L1_CACHE_BYTES / locksz, 1U); - nblocks = roundup_pow_of_two(nblocks * num_possible_cpus()); + if (locksz == 0) + goto set_mask; - /* no more locks than number of hash buckets */ - nblocks = min(nblocks, hashinfo->ehash_mask + 1); + /* Allocate 2 cache lines or at least one spinlock per cpu. */ + nblocks = max(2U * L1_CACHE_BYTES / locksz, 1U) * num_possible_cpus(); - hashinfo->ehash_locks = kvmalloc_array(nblocks, locksz, GFP_KERNEL); - if (!hashinfo->ehash_locks) - return -ENOMEM; + /* At least one page per NUMA node. */ + nblocks = max(nblocks, num_online_nodes() * PAGE_SIZE / locksz); + + nblocks = roundup_pow_of_two(nblocks); + + /* No more locks than number of hash buckets. */ + nblocks = min(nblocks, hashinfo->ehash_mask + 1); - for (i = 0; i < nblocks; i++) - spin_lock_init(&hashinfo->ehash_locks[i]); + if (num_online_nodes() > 1) { + /* Use vmalloc() to allow NUMA policy to spread pages + * on all available nodes if desired. + */ + ptr = vmalloc_array(nblocks, locksz); + } + if (!ptr) { + ptr = kvmalloc_array(nblocks, locksz, GFP_KERNEL); + if (!ptr) + return -ENOMEM; } + for (i = 0; i < nblocks; i++) + spin_lock_init(&ptr[i]); + hashinfo->ehash_locks = ptr; +set_mask: hashinfo->ehash_locks_mask = nblocks - 1; return 0; } -- 2.39.5