From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 99C8E39FCC1 for ; Mon, 6 Apr 2026 23:40:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775518810; cv=none; b=ZheKDFXBjpBv3sGHd2e1VPD7WKW/7FO+CAcjZemrmqokvRVi3DZogajvliMye/BJyzLI0fyhj7NOjkEJzmRy9xwnDNa2Vtw7DeAanaocS2+V/XOGPn0SepvPe33dOvRyRGIXk4Ks3Fv9CBD9zg4aqEZHBez/0tqNNfnZRzgPJ+k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775518810; c=relaxed/simple; bh=oYuTgHASR13wx51gCN7dp7iKyzHqtjbJmTVztcALf64=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=l4/aSoMxMInBKymFFa+yHQW8ex644hFC3R27QpIv/exxJlKZ3fZV2EnHotaNO6po4Ih0M4MDt1M3kmahT/SyRiebZIekBpIDLCaXnVuvG/inDAuoYxKYAaZVzWVvJejQ84FlOvo5nq4aV8oVzXPoWbmNPjSTlcvBvPRxkA6JMfs= 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=osNL2Te6; arc=none smtp.client-ip=209.85.214.202 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="osNL2Te6" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-2b24af7ca99so58096915ad.1 for ; Mon, 06 Apr 2026 16:40:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1775518808; x=1776123608; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=A8l16tATZuU70nyjoOFEBJeX0fkq5enqtuO7E7lUUZk=; b=osNL2Te6mnP5n7lsFBeAHx3ITyRloNPZeWO2hzOVnFC5rDGjUqtzIsNlrqM08rFN+g TaIqSV1x6PwKmEG5uhgVdltNhd3JYJ26zHwXqucwuGRttlLEbCoLCfWzBrarDrEztTOE B9aJmGi4VZmFzEw0aXYBmmYUqtOrh+1S8lCHf8U47WSVWIsXVgymZE1dxbqtTsYcyZ/b AKu42vx2EIpjIBqiesObLmBTBDCS4WWMamckBU4aMzT1Gr+mTr5uaNn/J3Jb266upzMf cPNXcTo+o7hyJ4ZX2hOF96E50sKeBFF4So7s3OMggko36iKRGw4pU43J0iDSCVKPoAHx WAwQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775518808; x=1776123608; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=A8l16tATZuU70nyjoOFEBJeX0fkq5enqtuO7E7lUUZk=; b=JMIgrlf647367j4G+lpcElbk8AoFVgzhKJCANtchdTuBEog0+vrBJJcbr5OM4ICprR meomXxgC7TmoseVL/gk311jfVhPl28dgP0Bn7d5u1Gc+1RcvzQP71UA97GdBtGaaCM7w bo4DoPJwmc/7+CATdDop+3Muh9DPnUiqGIXO8+Xj+ggZjoU+TwYYP/ZOqZ3OwILgtMu0 k8GGMAwx7alwIUghHmcw2Rm7/bzjVU1V4lZeCSRnT4HjXxPD3EPhSvr+kRGVMvjkeX8U awYhUJoVlK/mZf5EREn9dxTeAD8o/rfrmky2IyItR7LmVWWXDpc3YWL9m04VbqCKtctH KE5g== X-Gm-Message-State: AOJu0YxepVGWPqmjqe/H8osbfSNBtj/u6Vx6kUjAlV3VkvAh7f+FkGT1 /MCiuamJbSO79TZ7xeUY9QtTIOePDIV3wOG4HeXToDy2AYXwE7IDj24rzcQNVV+8/0S7qiOa+HO ZOx98lNXg9/TWQ0d/OPKWwIStUihYj0Adp3DOKNOrBn542HiX7/b3z/oQ6w0Oiz6Pz7oMKiviS2 smsMXI44CMj8LIAfozBJ7g8+sFkvQc0SDG5Eyj1ynh5LWUsbXngFhDzDUehKsPbEc= X-Received: from plbld6.prod.google.com ([2002:a17:902:fac6:b0:2b0:4b14:f0e9]) (user=hramamurthy job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:2c04:b0:2b0:5075:96d1 with SMTP id d9443c01a7336-2b28176a618mr154776505ad.24.1775518807765; Mon, 06 Apr 2026 16:40:07 -0700 (PDT) Date: Mon, 6 Apr 2026 23:40:01 +0000 In-Reply-To: <20260406234002.3610542-1-hramamurthy@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260406234002.3610542-1-hramamurthy@google.com> X-Mailer: git-send-email 2.53.0.1213.gd9a14994de-goog Message-ID: <20260406234002.3610542-3-hramamurthy@google.com> Subject: [PATCH net-next v4 2/3] gve: make nic clock reads thread safe 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: Ankit Garg Add a mutex to protect the shared DMA buffer that receives NIC timestamp reports. The NIC timestamp will be read from two different threads: the periodic worker and upcoming `gettimex64`. Move clock registration to the last step of initialization to ensure that all data needed by the clock module is initialized before the clock is exposed to usermode. Reviewed-by: Joshua Washington Signed-off-by: Ankit Garg Signed-off-by: Jordan Rhee Signed-off-by: Harshitha Ramamurthy --- Changes in v3: - Reorder init/teardown to register PTP clock last, and simplify code - Move ptp-related members from gve_priv to gve_ptp - Only assign priv->ptp after ptp module is successfully initialized --- drivers/net/ethernet/google/gve/gve.h | 12 +- drivers/net/ethernet/google/gve/gve_ethtool.c | 3 +- drivers/net/ethernet/google/gve/gve_ptp.c | 134 ++++++++---------- 3 files changed, 63 insertions(+), 86 deletions(-) diff --git a/drivers/net/ethernet/google/gve/gve.h b/drivers/net/ethernet/google/gve/gve.h index 1d66d3834f7e..7b69d0cfc0d5 100644 --- a/drivers/net/ethernet/google/gve/gve.h +++ b/drivers/net/ethernet/google/gve/gve.h @@ -792,6 +792,9 @@ struct gve_ptp { struct ptp_clock_info info; struct ptp_clock *clock; struct gve_priv *priv; + struct mutex nic_ts_read_lock; /* Protects nic_ts_report */ + struct gve_nic_ts_report *nic_ts_report; + dma_addr_t nic_ts_report_bus; }; struct gve_priv { @@ -923,8 +926,6 @@ struct gve_priv { bool nic_timestamp_supported; struct gve_ptp *ptp; struct kernel_hwtstamp_config ts_config; - struct gve_nic_ts_report *nic_ts_report; - dma_addr_t nic_ts_report_bus; u64 last_sync_nic_counter; /* Clock counter from last NIC TS report */ }; @@ -1201,7 +1202,7 @@ static inline bool gve_supports_xdp_xmit(struct gve_priv *priv) static inline bool gve_is_clock_enabled(struct gve_priv *priv) { - return priv->nic_ts_report; + return priv->ptp; } /* gqi napi handler defined in gve_main.c */ @@ -1321,14 +1322,9 @@ int gve_flow_rules_reset(struct gve_priv *priv); int gve_init_rss_config(struct gve_priv *priv, u16 num_queues); /* PTP and timestamping */ #if IS_ENABLED(CONFIG_PTP_1588_CLOCK) -int gve_clock_nic_ts_read(struct gve_priv *priv); int gve_init_clock(struct gve_priv *priv); void gve_teardown_clock(struct gve_priv *priv); #else /* CONFIG_PTP_1588_CLOCK */ -static inline int gve_clock_nic_ts_read(struct gve_priv *priv) -{ - return -EOPNOTSUPP; -} static inline int gve_init_clock(struct gve_priv *priv) { diff --git a/drivers/net/ethernet/google/gve/gve_ethtool.c b/drivers/net/ethernet/google/gve/gve_ethtool.c index dc2213b5ce24..4fd7e8a442c5 100644 --- a/drivers/net/ethernet/google/gve/gve_ethtool.c +++ b/drivers/net/ethernet/google/gve/gve_ethtool.c @@ -972,8 +972,7 @@ static int gve_get_ts_info(struct net_device *netdev, info->rx_filters |= BIT(HWTSTAMP_FILTER_NONE) | BIT(HWTSTAMP_FILTER_ALL); - if (priv->ptp) - info->phc_index = ptp_clock_index(priv->ptp->clock); + info->phc_index = ptp_clock_index(priv->ptp->clock); } return 0; diff --git a/drivers/net/ethernet/google/gve/gve_ptp.c b/drivers/net/ethernet/google/gve/gve_ptp.c index 06b1cf4a5efc..ad15f1209a83 100644 --- a/drivers/net/ethernet/google/gve/gve_ptp.c +++ b/drivers/net/ethernet/google/gve/gve_ptp.c @@ -11,19 +11,20 @@ #define GVE_NIC_TS_SYNC_INTERVAL_MS 250 /* Read the nic timestamp from hardware via the admin queue. */ -int gve_clock_nic_ts_read(struct gve_priv *priv) +static int gve_clock_nic_ts_read(struct gve_ptp *ptp, u64 *nic_raw) { - u64 nic_raw; int err; - err = gve_adminq_report_nic_ts(priv, priv->nic_ts_report_bus); + mutex_lock(&ptp->nic_ts_read_lock); + err = gve_adminq_report_nic_ts(ptp->priv, ptp->nic_ts_report_bus); if (err) - return err; + goto out; - nic_raw = be64_to_cpu(priv->nic_ts_report->nic_timestamp); - WRITE_ONCE(priv->last_sync_nic_counter, nic_raw); + *nic_raw = be64_to_cpu(ptp->nic_ts_report->nic_timestamp); - return 0; +out: + mutex_unlock(&ptp->nic_ts_read_lock); + return err; } static int gve_ptp_gettimex64(struct ptp_clock_info *info, @@ -41,17 +42,21 @@ static int gve_ptp_settime64(struct ptp_clock_info *info, static long gve_ptp_do_aux_work(struct ptp_clock_info *info) { - const struct gve_ptp *ptp = container_of(info, struct gve_ptp, info); + struct gve_ptp *ptp = container_of(info, struct gve_ptp, info); struct gve_priv *priv = ptp->priv; + u64 nic_raw; int err; if (gve_get_reset_in_progress(priv) || !gve_get_admin_queue_ok(priv)) goto out; - err = gve_clock_nic_ts_read(priv); - if (err && net_ratelimit()) - dev_err(&priv->pdev->dev, - "%s read err %d\n", __func__, err); + err = gve_clock_nic_ts_read(ptp, &nic_raw); + if (err) { + dev_err_ratelimited(&priv->pdev->dev, "%s read err %d\n", + __func__, err); + goto out; + } + WRITE_ONCE(priv->last_sync_nic_counter, nic_raw); out: return msecs_to_jiffies(GVE_NIC_TS_SYNC_INTERVAL_MS); @@ -65,94 +70,71 @@ static const struct ptp_clock_info gve_ptp_caps = { .do_aux_work = gve_ptp_do_aux_work, }; -static int gve_ptp_init(struct gve_priv *priv) +int gve_init_clock(struct gve_priv *priv) { struct gve_ptp *ptp; + u64 nic_raw; int err; - priv->ptp = kzalloc_obj(*priv->ptp); - if (!priv->ptp) + ptp = kzalloc_obj(*priv->ptp); + if (!ptp) return -ENOMEM; - ptp = priv->ptp; ptp->info = gve_ptp_caps; - ptp->clock = ptp_clock_register(&ptp->info, &priv->pdev->dev); - - if (IS_ERR(ptp->clock)) { - dev_err(&priv->pdev->dev, "PTP clock registration failed\n"); - err = PTR_ERR(ptp->clock); - goto free_ptp; - } - ptp->priv = priv; - return 0; - -free_ptp: - kfree(ptp); - priv->ptp = NULL; - return err; -} - -static void gve_ptp_release(struct gve_priv *priv) -{ - struct gve_ptp *ptp = priv->ptp; - - if (!ptp) - return; - - if (ptp->clock) - ptp_clock_unregister(ptp->clock); - - kfree(ptp); - priv->ptp = NULL; -} - -int gve_init_clock(struct gve_priv *priv) -{ - int err; - - err = gve_ptp_init(priv); - if (err) - return err; - - priv->nic_ts_report = + mutex_init(&ptp->nic_ts_read_lock); + ptp->nic_ts_report = dma_alloc_coherent(&priv->pdev->dev, sizeof(struct gve_nic_ts_report), - &priv->nic_ts_report_bus, - GFP_KERNEL); - if (!priv->nic_ts_report) { + &ptp->nic_ts_report_bus, GFP_KERNEL); + if (!ptp->nic_ts_report) { dev_err(&priv->pdev->dev, "%s dma alloc error\n", __func__); err = -ENOMEM; - goto release_ptp; + goto free_ptp; } - err = gve_clock_nic_ts_read(priv); + + err = gve_clock_nic_ts_read(ptp, &nic_raw); if (err) { dev_err(&priv->pdev->dev, "failed to read NIC clock %d\n", err); - goto release_nic_ts_report; + goto free_dma_mem; } - ptp_schedule_worker(priv->ptp->clock, + WRITE_ONCE(priv->last_sync_nic_counter, nic_raw); + + ptp->clock = ptp_clock_register(&ptp->info, &priv->pdev->dev); + if (IS_ERR(ptp->clock)) { + dev_err(&priv->pdev->dev, "PTP clock registration failed\n"); + err = PTR_ERR(ptp->clock); + goto free_dma_mem; + } + + priv->ptp = ptp; + ptp_schedule_worker(ptp->clock, msecs_to_jiffies(GVE_NIC_TS_SYNC_INTERVAL_MS)); return 0; -release_nic_ts_report: - dma_free_coherent(&priv->pdev->dev, - sizeof(struct gve_nic_ts_report), - priv->nic_ts_report, priv->nic_ts_report_bus); - priv->nic_ts_report = NULL; -release_ptp: - gve_ptp_release(priv); +free_dma_mem: + dma_free_coherent(&priv->pdev->dev, sizeof(struct gve_nic_ts_report), + ptp->nic_ts_report, ptp->nic_ts_report_bus); + ptp->nic_ts_report = NULL; +free_ptp: + mutex_destroy(&ptp->nic_ts_read_lock); + kfree(ptp); return err; } void gve_teardown_clock(struct gve_priv *priv) { - gve_ptp_release(priv); + struct gve_ptp *ptp = priv->ptp; - if (priv->nic_ts_report) { - dma_free_coherent(&priv->pdev->dev, - sizeof(struct gve_nic_ts_report), - priv->nic_ts_report, priv->nic_ts_report_bus); - priv->nic_ts_report = NULL; - } + if (!ptp) + return; + + priv->ptp = NULL; + ptp_clock_unregister(ptp->clock); + dma_free_coherent(&priv->pdev->dev, sizeof(struct gve_nic_ts_report), + ptp->nic_ts_report, ptp->nic_ts_report_bus); + ptp->nic_ts_report = NULL; + mutex_destroy(&ptp->nic_ts_read_lock); + kfree(ptp); } -- 2.53.0.1213.gd9a14994de-goog