From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-180.mta1.migadu.com (out-180.mta1.migadu.com [95.215.58.180]) (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 93CBEB640 for ; Sat, 18 Jan 2025 00:47:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737161242; cv=none; b=f+Jwp3VOKb2E5McI+uHq4ftn9SSMdJ4JnQc4r7beWtmg3xfiDcY9n5b75u1tlmSnIIH3Jqmfuxwhdx36OxRNi55qbwA4RxJvegv4YajEMy9BwoXkRFe8g8AbCickD3v5zmeXx/sYRVULR1vrjs8N9eIZ1zLlM9PA38nbEGrzfeE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737161242; c=relaxed/simple; bh=d7Cy1HBZ7uudLln/1KJycVHjr9lgFKrdOo1NmfPV+2g=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=drzGgtSKT4+w+YeAhHSI4kp82zgXCoHd+U0dzXqbqCGXW3Ey2rcd9JBYpmCpkF2lTKiFz7KliW5CSs68H/vbkrRFuz/oPd9xD7EvL1mcnn0q3++uKrkpKzPh9SKS+S9cqH5VmO9eEy+YmHLNpujXKhMkzHeIXKG7KfchhdGtZ08= 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=JNRnyQ47; arc=none smtp.client-ip=95.215.58.180 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="JNRnyQ47" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1737161228; 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=BRREM1BEEEqOBTIHUcVG5c4TyTNaF/eaJuYWhcxyST0=; b=JNRnyQ47gwTfRm8VdU+ufBHAlsuiMUEj8JYFWFqYQcSK3MVBQAGJFrLU87EBbQ6anQWesQ Sso5AhwhzZE2/siAN+6Zee6P9U4zL7j5LGntgQ3bPbTpgeZXXmAp+DlDADgXELln9ACx4U 4mPzIv7Cc2DSgKsLpVQPa7BwX97AWw0= Date: Fri, 17 Jan 2025 16:46:56 -0800 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH net-next v5 08/15] net-timestamp: support sw SCM_TSTAMP_SND for bpf extension To: Jason Xing Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, dsahern@kernel.org, willemdebruijn.kernel@gmail.com, willemb@google.com, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, song@kernel.org, yonghong.song@linux.dev, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@fomichev.me, haoluo@google.com, jolsa@kernel.org, horms@kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org References: <20250112113748.73504-1-kerneljasonxing@gmail.com> <20250112113748.73504-9-kerneljasonxing@gmail.com> 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: 8bit X-Migadu-Flow: FLOW_OUT On 1/15/25 3:56 PM, Jason Xing wrote: > On Thu, Jan 16, 2025 at 6:48 AM Martin KaFai Lau wrote: >> >> On 1/12/25 3:37 AM, Jason Xing wrote: >>> Support SCM_TSTAMP_SND case. Then we will get the software >>> timestamp when the driver is about to send the skb. Later, I >>> will support the hardware timestamp. >> >>> diff --git a/net/core/skbuff.c b/net/core/skbuff.c >>> index 169c6d03d698..0fb31df4ed95 100644 >>> --- a/net/core/skbuff.c >>> +++ b/net/core/skbuff.c >>> @@ -5578,6 +5578,9 @@ static void __skb_tstamp_tx_bpf(struct sk_buff *skb, struct sock *sk, int tstype >>> case SCM_TSTAMP_SCHED: >>> op = BPF_SOCK_OPS_TS_SCHED_OPT_CB; >>> break; >>> + case SCM_TSTAMP_SND: >>> + op = BPF_SOCK_OPS_TS_SW_OPT_CB; >> >> For the hwtstamps case, is skb_hwtstamps(skb) set? From looking at a few >> drivers, it does not look like it. I don't see the hwtstamps support in patch 10 >> either. What did I miss ? > > Sorry, I missed adding a new flag, namely, BPF_SOCK_OPS_TS_HW_OPT_CB. > I can also skip adding that new one and rename > BPF_SOCK_OPS_TS_SW_OPT_CB accordingly for sw and hw cases if we > finally decide to use hwtstamps parameter to distinguish two different > cases. I think having a separate BPF_SOCK_OPS_TS_HW_OPT_CB is better considering your earlier hwtstamps may be NULL comment. I don't see the drivers I looked at passing NULL though but the comment of skb_tstamp_tx did say it may be NULL :/ Regardless, afaict, skb_hwtstamps(skb) is still not set to the hwtstamps passed by the driver here. The bpf prog is supposed to directly get the hwtstamps from the skops->skb pointer.