From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) (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 0E1F64681 for ; Sat, 30 Apr 2022 00:28:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1651278493; x=1682814493; h=date:from:to:cc:subject:in-reply-to:message-id: references:mime-version; bh=KweQ0AYmYRQgyhYl6zfc8vormSESCkGHPr7Yu4/5LSg=; b=gAHjOXiz5RryPHHIMIJon0nAEgKR9WTapCwrmbNKVjbZvf94ERbGk8/O HbFPwQrkbwgPXtpKQrOwKUnJNUdy6KjBU0SrJSYk9FdikK1t0bi3E4BNc vvvqMnX2VzDgXi1R8V74ajqwekG5AAYCxI1lRVKHIrq/ucstyikIBCywn DiTivaf63rXFBPOSv7yyQEL8AlYazP2F51/k4DSP6tBSVfpYJ3u3IQK4O BxB4txrWB91hl5nzTpuhTpwn3xz+7pOkMW4rUF5V700SsqpV6HjRjokQF bibanBErhPyQlJxfXHQnb2eesjeT+7D/VfgEBHiwwVBztGks5kLOl4eeb A==; X-IronPort-AV: E=McAfee;i="6400,9594,10332"; a="246722807" X-IronPort-AV: E=Sophos;i="5.91,186,1647327600"; d="scan'208";a="246722807" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Apr 2022 17:28:12 -0700 X-IronPort-AV: E=Sophos;i="5.91,186,1647327600"; d="scan'208";a="685725588" Received: from mdbellow-mobl.amr.corp.intel.com ([10.209.122.4]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Apr 2022 17:28:12 -0700 Date: Fri, 29 Apr 2022 17:28:12 -0700 (PDT) From: Mat Martineau To: Geliang Tang cc: mptcp@lists.linux.dev Subject: Re: [PATCH mptcp-next v9 2/3] selftests: bpf: add bpf_rr scheduler In-Reply-To: <1d2ecaada853df447dcfa6c8fabcf7bec5576278.1651243739.git.geliang.tang@suse.com> Message-ID: <2fb06c54-39ca-68a6-70a2-ca6b41d4e9fb@linux.intel.com> References: <1d2ecaada853df447dcfa6c8fabcf7bec5576278.1651243739.git.geliang.tang@suse.com> Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset=US-ASCII On Fri, 29 Apr 2022, Geliang Tang wrote: > This patch implements the round-robin BPF MPTCP scheduler, named bpf_rr, > which always picks the next available subflow to send data. If no such > next subflow available, picks the first one. > > Signed-off-by: Geliang Tang > --- > .../testing/selftests/bpf/bpf_mptcp_helpers.h | 5 ++ > .../selftests/bpf/progs/mptcp_bpf_rr.c | 49 +++++++++++++++++++ > 2 files changed, 54 insertions(+) > create mode 100644 tools/testing/selftests/bpf/progs/mptcp_bpf_rr.c > > diff --git a/tools/testing/selftests/bpf/bpf_mptcp_helpers.h b/tools/testing/selftests/bpf/bpf_mptcp_helpers.h > index 1fe3d0a97429..8ce5b1603962 100644 > --- a/tools/testing/selftests/bpf/bpf_mptcp_helpers.h > +++ b/tools/testing/selftests/bpf/bpf_mptcp_helpers.h > @@ -37,4 +37,9 @@ struct mptcp_sock { > char ca_name[TCP_CA_NAME_MAX]; > } __attribute__((preserve_access_index)); > > +struct mptcp_subflow_context { > + __u32 token; > + struct sock *tcp_sock; /* tcp sk backpointer */ > +} __attribute__((preserve_access_index)); > + > #endif > diff --git a/tools/testing/selftests/bpf/progs/mptcp_bpf_rr.c b/tools/testing/selftests/bpf/progs/mptcp_bpf_rr.c > new file mode 100644 > index 000000000000..2f31de4cfc84 > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/mptcp_bpf_rr.c > @@ -0,0 +1,49 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* Copyright (c) 2022, SUSE. */ > + > +#include > +#include > +#include > +#include "bpf_mptcp_helpers.h" > + > +char _license[] SEC("license") = "GPL"; > + > +SEC("struct_ops/mptcp_sched_rr_init") > +void BPF_PROG(mptcp_sched_rr_init, struct mptcp_sock *msk) > +{ > +} > + > +SEC("struct_ops/mptcp_sched_rr_release") > +void BPF_PROG(mptcp_sched_rr_release, struct mptcp_sock *msk) > +{ > +} > + > +void BPF_STRUCT_OPS(bpf_rr_get_subflow, struct mptcp_sock *msk, > + bool reinject, struct mptcp_sched_data *data) > +{ > + struct mptcp_subflow_context *subflow; > + struct sock *ssk = msk->first; > + > + for (int i = 0; i < MPTCP_SUBFLOWS_MAX; i++) { > + if (i >= data->subflows) > + break; Is the extra 'if' statement required by the BPF verifier? If this is not allowed: for (int i = 0; i < MPTCP_SUBFLOWS_MAX; i++) is this? for (int i = 0; i < MPTCP_SUBFLOWS_MAX && i < data->subflows; i++) > + > + subflow = data->array[i]; > + if (subflow->tcp_sock != msk->last_snd) { > + ssk = subflow->tcp_sock; > + break; > + } > + } > + > + msk->last_snd = ssk; > + data->sock = ssk; > + data->call_again = 0; > +} > + > +SEC(".struct_ops") > +struct mptcp_sched_ops rr = { > + .init = (void *)mptcp_sched_rr_init, > + .release = (void *)mptcp_sched_rr_release, > + .get_subflow = (void *)bpf_rr_get_subflow, > + .name = "bpf_rr", > +}; > -- > 2.34.1 > > > -- Mat Martineau Intel