From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DA3293191BB for ; Mon, 6 Apr 2026 23:40:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775518807; cv=none; b=FE8zN8u+XQ6oZTRcRZjtOVlJS71WgyVxhSrkDmS4cd+w/l22AHBGG4BNLRNJhqrDV6Z5CkiWYgd1Mb0OCUQUNfoM360ANbFW1NqNwF+QHCi3tBAh3y5bPtPZRkBYOVyJ4EPNECTeB19Bsor8JUQ6dqXPKtpAgLOJwy+xSw82amA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775518807; c=relaxed/simple; bh=mGt75SnvaPRypeP+PnFAZmsCVL+F9lljS2GpxdG288Q=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=mHAXCWGNL14Q5YoE6U1XXqCYdPhONnYFHPE3zKGpbRBsSGzQOAPmM1aC0a+WwzAvIDA99EyuH7FqPw/fA/C4uc4KbqPk3Cp+qmQ56mKs0bc1ATK+tvNsqo28YbWGNnL6D+fJqpc5MRAC6CJhT9sAfOkqLRekm89ajQjHSeYKnWw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--hramamurthy.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=GrjAOLZY; arc=none smtp.client-ip=209.85.214.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--hramamurthy.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="GrjAOLZY" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-2b250d3699aso108969145ad.2 for ; Mon, 06 Apr 2026 16:40:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1775518805; x=1776123605; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=1hcYTP3VT53MAcPTyOSTzBSmynY4NyEpZMracFsGLhc=; b=GrjAOLZYndynJXhTGlJABZKrYIkOn9+Qw0/8fp8RbFoH5bUqSGn0oti4z52ncMzQzZ ZnCu7+oW/gsreW2eOqwhWmNTGpxuHf/FrwwPB98dq3/dNUhBd2hiCZBunbapAt9QRx6/ RZDPZH+DD7Rfc2pjgF+vnClKM0QnOhiY80EF6y6ncV7RonzQFdAV89Rr1Ysc2j+B/Otj g/5nDult53Pl3BIX4pBXn0kMaOf3gbF3Uhmiti/84Dd3nTyD4PsRMkFdHYnKTvDaHw+/ mp3J6YYHeVIQnSPHsBhDyjHdIWcrQ+BoGAZLH/YPCsoGX2ZYCay6FesNJVJ0oePkdZWk VDMg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775518805; x=1776123605; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=1hcYTP3VT53MAcPTyOSTzBSmynY4NyEpZMracFsGLhc=; b=oHX5v7rLSwyycaBXozA8+NduUIofi5a3qfIvk/YhM3W135VpLMxrnWgu3advKRZUiY v4rndkvpGIdJsBV5z7DU2rtD5KFaSvVK/Be6MaGZDkrks2200u6l6kxgYCq5XaL3RLv0 323s/zSu1qyk5mLa4p8ijSoaYtSmCn5eJNkzEnnohIupGM3jSkPccFbmWP6nbbzXQCIw u0h85RsO3Y88OXagTGZumXW9UTiU7KSRbPmBrD1DfK4nvMKj6KZP/eYSTmRDmZOLamfE NsYXybVTQMkHz2vlt1U9sTBnrGPVT2HT2L5FiQtQGFPcV0JWHCVDslgUwHtJG3heyg1d P9CA== X-Gm-Message-State: AOJu0YxFT+v7WXcxM4fb+2DaExh0yjkqXswbJeIHe5INS4q+Wf1YXXSa yq6t1ThffWjFmnfs3nIFpBp734Yl8TEVNlAn7OE540RTBZYmeDzlL8DakBguOj4dV2f6gM8tbfc Ah6ivoAj0w6oeOTuYRAITVh72AgGajFcftDcWOMAFQHHrnmvviMS2TmJnwsq0wK769ntCQ0YfvR /HmQ3F/3Tx7auEbZul/5wzcRNrRFOIRJHalsWG5Ts0jVniDruq68RKwsCP9cZUkOY= X-Received: from plbms7.prod.google.com ([2002:a17:903:ac7:b0:2b2:6f73:54e0]) (user=hramamurthy job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:3c47:b0:2b0:67a7:5c4b with SMTP id d9443c01a7336-2b281802d24mr160270145ad.28.1775518805097; Mon, 06 Apr 2026 16:40:05 -0700 (PDT) Date: Mon, 6 Apr 2026 23:39:59 +0000 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.53.0.1213.gd9a14994de-goog Message-ID: <20260406234002.3610542-1-hramamurthy@google.com> Subject: [PATCH net-next v4 0/3] gve: add support for PTP gettimex64 From: Harshitha Ramamurthy To: netdev@vger.kernel.org Cc: joshwash@google.com, hramamurthy@google.com, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, richardcochran@gmail.com, willemb@google.com, nktgrg@google.com, jfraker@google.com, ziweixiao@google.com, maolson@google.com, thostet@google.com, jordanrhee@google.com, jefrogers@google.com, alok.a.tiwari@oracle.com, yyd@google.com, jacob.e.keller@intel.com, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" From: Jordan Rhee This patch series adds support to obtain near-simultaneous NIC and system timestamps with gettimex64. This enables daemons like chrony and phc2sys to synchronize the system clock to the NIC clock. GVE does not have direct register access to the NIC hardware clock, so it must issue an AdminQ command to read the NIC clock. Due to relatively high latency of AQ commands (~100us), it is necessary for the hypervisor to sample the system time sandwich inside the AQ command. The first two patches pave the way for the PTP implementation by quieting excessive logging and refactoring an existing routine for thread safety. When tested inside a GCE C3 VM, this enabled chrony to synchronize the NIC clock and system clock with sub-microsecond precision. chronyc tracking Reference ID : 50484330 (PHC0) Stratum : 1 Ref time (UTC) : Sat Feb 14 01:53:42 2026 System time : 0.000000001 seconds fast of NTP time Last offset : -0.000000000 seconds RMS offset : 0.000000001 seconds Frequency : 0.686 ppm fast Residual freq : -0.000 ppm Skew : 0.001 ppm Root delay : 0.000000001 seconds Root dispersion : 0.000000812 seconds Update interval : 0.5 seconds Leap status : Normal --- Changelog: V4: - call out change to dev_err_ratelimited() in patch 1 commit message (Jacob Keller) - Ensure only one log is emitted when command returns GVE_ADMINQ_COMMAND_UNSET (Jacob Keller) - Link to v3: https://lore.kernel.org/netdev/20260403194427.1830609-1-hramamurthy@google.com/ V3: - Take system time snapshot inside the mutex - Return -EOPNOTSUPP if cross-timestamp is requested on an arch other than x86 or arm64 - Fix initialization to only register PTP clock once all data is initialized - Link to v2: https://lore.kernel.org/netdev/20260326224527.1044097-1-hramamurthy@google.com/ V2: - Fixed compilation warning on ARM by casting to u64 - Link to v1: https://lore.kernel.org/netdev/20260323234829.3185051-1-hramamurthy@google.com/ --- Ankit Garg (1): gve: make nic clock reads thread safe Jordan Rhee (2): gve: skip error logging for retryable AdminQ commands gve: implement PTP gettimex64 drivers/net/ethernet/google/gve/gve.h | 12 +- drivers/net/ethernet/google/gve/gve_adminq.c | 27 +- drivers/net/ethernet/google/gve/gve_adminq.h | 4 +- drivers/net/ethernet/google/gve/gve_ethtool.c | 3 +- drivers/net/ethernet/google/gve/gve_ptp.c | 317 +++++++++++++----- 5 files changed, 268 insertions(+), 95 deletions(-) base-commit: 5446b8691eb8278f10deca92048fad84ffd1e4d5 -- 2.53.0.1213.gd9a14994de-goog