From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-186.mta1.migadu.com (out-186.mta1.migadu.com [95.215.58.186]) (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 93E00138C for ; Tue, 7 May 2024 00:54:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.186 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715043264; cv=none; b=LSlOeN28f6CVho4IysxKvObeTnQEdzRS+TsR/JvWHqc5t+gVso3Lz6WHw5+dc8Z3JeKXTqXLIaVQFgyDxcDsddyACk7lzu5IyQMhCNfNaBYjxo7GQ1iJJIFx8TXMg1dwsp2Luu8Z9b0aOUZk6/940zVqSGdVwpiDyF3OI+39eXc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715043264; c=relaxed/simple; bh=o8Bc5Ez/6YqYURlwwo5HZX/zfkTVwJuvYFnD3wNE9ys=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=d7/Xkifh/0gz7WRn9s6noHN7bXrz95TswyrWv+bXwIr7Q6Cu21QyG2BmZXoJ3F2p5A+xRHexUWyUaBqZEuKx5itt2JgLhSci+MTaw5BYcOK7ZPndbmHKQhHo4oCTfnF+khMhIXA80liTWW0rzht/ioV/JkZvG+DGcb1g6yTFHXo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=LkK5+wzm; arc=none smtp.client-ip=95.215.58.186 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="LkK5+wzm" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1715043258; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EkN5x92xDG37kTOdUdSnJWPAN51eOIj86lnHKaDFNr0=; b=LkK5+wzmXqo5sFsIhsMoTy0VapcDfqDuxZ3bfxSNryi85yj7zKlSdh+mFCFFcQCLYMRSJj TcSTdH1wcZC4ssayEtP5BM1mvNQEMHg029Xyq2bFVaS8lOF544saj0ciaq1yvd1nR/v0JP OZAckBjKAHxAuJT5NGL77nQS9sWwcN0= Date: Mon, 6 May 2024 17:54:13 -0700 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [RFC PATCH bpf-next v6 3/3] selftests/bpf: Handle forwarding of UDP CLOCK_TAI packets To: "Abhishek Chauhan (ABC)" Cc: Willem de Bruijn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Andrew Halaney , Martin KaFai Lau , Daniel Borkmann , bpf , kernel@quicinc.com References: <20240504031331.2737365-1-quic_abchauha@quicinc.com> <20240504031331.2737365-4-quic_abchauha@quicinc.com> <663929b249143_516de2945@willemb.c.googlers.com.notmuch> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Martin KaFai Lau In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 5/6/24 1:50 PM, Abhishek Chauhan (ABC) wrote: > > > On 5/6/2024 12:04 PM, Willem de Bruijn wrote: >> Abhishek Chauhan wrote: >>> With changes in the design to forward CLOCK_TAI in the skbuff >>> framework, existing selftest framework needs modification >>> to handle forwarding of UDP packets with CLOCK_TAI as clockid. >>> >>> Link: https://lore.kernel.org/netdev/bc037db4-58bb-4861-ac31-a361a93841d3@linux.dev/ >>> Signed-off-by: Abhishek Chauhan >>> --- >>> tools/include/uapi/linux/bpf.h | 15 ++++--- >>> .../selftests/bpf/prog_tests/ctx_rewrite.c | 10 +++-- >>> .../selftests/bpf/prog_tests/tc_redirect.c | 3 -- >>> .../selftests/bpf/progs/test_tc_dtime.c | 39 +++++++++---------- >>> 4 files changed, 34 insertions(+), 33 deletions(-) >>> >>> diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h >>> index 90706a47f6ff..25ea393cf084 100644 >>> --- a/tools/include/uapi/linux/bpf.h >>> +++ b/tools/include/uapi/linux/bpf.h >>> @@ -6207,12 +6207,17 @@ union { \ >>> __u64 :64; \ >>> } __attribute__((aligned(8))) >>> >>> +/* The enum used in skb->tstamp_type. It specifies the clock type >>> + * of the time stored in the skb->tstamp. >>> + */ >>> enum { >>> - BPF_SKB_TSTAMP_UNSPEC, >>> - BPF_SKB_TSTAMP_DELIVERY_MONO, /* tstamp has mono delivery time */ >>> - /* For any BPF_SKB_TSTAMP_* that the bpf prog cannot handle, >>> - * the bpf prog should handle it like BPF_SKB_TSTAMP_UNSPEC >>> - * and try to deduce it by ingress, egress or skb->sk->sk_clockid. >>> + BPF_SKB_TSTAMP_UNSPEC = 0, /* DEPRECATED */ >>> + BPF_SKB_TSTAMP_DELIVERY_MONO = 1, /* DEPRECATED */ >>> + BPF_SKB_CLOCK_REALTIME = 0, >>> + BPF_SKB_CLOCK_MONOTONIC = 1, >>> + BPF_SKB_CLOCK_TAI = 2, >>> + /* For any future BPF_SKB_CLOCK_* that the bpf prog cannot handle, >>> + * the bpf prog can try to deduce it by ingress/egress/skb->sk->sk_clockid. >>> */ >>> }; >>> >>> diff --git a/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c b/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c >>> index 3b7c57fe55a5..71940f4ef0fb 100644 >>> --- a/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c >>> +++ b/tools/testing/selftests/bpf/prog_tests/ctx_rewrite.c >>> @@ -69,15 +69,17 @@ static struct test_case test_cases[] = { >>> { >>> N(SCHED_CLS, struct __sk_buff, tstamp), >>> .read = "r11 = *(u8 *)($ctx + sk_buff::__mono_tc_offset);" >>> - "w11 &= 3;" >>> - "if w11 != 0x3 goto pc+2;" >>> + "if w11 == 0x4 goto pc+1;" >>> + "goto pc+4;" >>> + "if w11 == 0x3 goto pc+1;" >>> + "goto pc+2;" >> >> Not an expert on this code, and I see that the existing code already >> has this below, but: isn't it odd and unnecessary to jump to an >> unconditional jump statement? >> > I am closely looking into your comment and i will evalute it(Martin can correct me > if the jumps are correct or not as i am new to BPF as well) but i found out that > JSET = "&" and not "==". So the above two ins has to change from - Yes, this should be bitwise "&" instead of "==". The bpf CI did report this: https://github.com/kernel-patches/bpf/actions/runs/8947652196/job/24579927178 Please monitor the bpf CI test result. Do you have issue running the test locally? > > "if w11 == 0x4 goto pc+1;" ==>(needs to be corrected to) "if w11 & 0x4 goto pc+1;" > "if w11 == 0x3 goto pc+1;" ==> (needs to be correct to) "if w11 & 0x3 goto pc+1;" > > >>> "$dst = 0;" >>> "goto pc+1;" >>> "$dst = *(u64 *)($ctx + sk_buff::tstamp);", >>> .write = "r11 = *(u8 *)($ctx + sk_buff::__mono_tc_offset);" >>> - "if w11 & 0x2 goto pc+1;" >>> + "if w11 & 0x4 goto pc+1;" >>> "goto pc+2;" >>> - "w11 &= -2;" >>> + "w11 &= -3;" > Martin, > Also i am not sure why the the dissembly complains because the value of SKB_TSTAMP_TYPE_MASK = 3 and we are > negating it ~3 = -3. > > Can't match disassembly(left) with pattern(right): > r11 = *(u8 *)(r1 +129) ; r11 = *(u8 *)($ctx + sk_buff::__mono_tc_offset) > if w11 & 0x4 goto pc+1 ; if w11 & 0x4 goto pc+1 > goto pc+2 ; goto pc+2 > w11 &= -4 ; w11 &= -3 > >>> "*(u8 *)($ctx + sk_buff::__mono_tc_offset) = r11;" >>> "*(u64 *)($ctx + sk_buff::tstamp) = $src;", >>> },