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Date:   Fri, 7 Jul 2023 02:51:22 -0700
From:   Souradeep Chakrabarti <schakrabarti@linux.microsoft.com>
To:     Leon Romanovsky <leon@kernel.org>
Cc:     kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org,
        decui@microsoft.com, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com, longli@microsoft.com,
        sharmaajay@microsoft.com, cai.huoqing@linux.dev,
        ssengar@linux.microsoft.com, vkuznets@redhat.com,
        tglx@linutronix.de, linux-hyperv@vger.kernel.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-rdma@vger.kernel.org, stable@vger.kernel.org,
        schakrabarti@microsoft.com
Subject: Re: [PATCH net] net: mana: Configure hwc timeout from hardware
Message-ID: <20230707095122.GB15082@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net>
References: <1688549578-12906-1-git-send-email-schakrabarti@linux.microsoft.com>
 <20230705104731.GM6455@unreal>
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On Wed, Jul 05, 2023 at 01:47:31PM +0300, Leon Romanovsky wrote:
> On Wed, Jul 05, 2023 at 02:32:58AM -0700, Souradeep Chakrabarti wrote:
> > At present hwc timeout value is a fixed value.
> > This patch sets the hwc timeout from the hardware.
> > 
> > Signed-off-by: Souradeep Chakrabarti <schakrabarti@linux.microsoft.com>
> > ---
> >  .../net/ethernet/microsoft/mana/gdma_main.c   | 27 +++++++++++++++++++
> >  .../net/ethernet/microsoft/mana/hw_channel.c  | 25 ++++++++++++++++-
> >  include/net/mana/gdma.h                       | 20 +++++++++++++-
> >  include/net/mana/hw_channel.h                 |  5 ++++
> >  4 files changed, 75 insertions(+), 2 deletions(-)
> 
> We are in merge window now, it is not net material.
> 
> > 
> > diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c
> > index 8f3f78b68592..5d30347e0137 100644
> > --- a/drivers/net/ethernet/microsoft/mana/gdma_main.c
> > +++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c
> > @@ -106,6 +106,30 @@ static int mana_gd_query_max_resources(struct pci_dev *pdev)
> >  	return 0;
> >  }
> >  
> > +static int mana_gd_query_hwc_timeout(struct pci_dev *pdev, u32 *timeout_val)
> > +{
> 
> Callers are not checking return value, so or make this function void or
> check return value.
I have fixed it in V2 patch.
> 
> > +	struct gdma_context *gc = pci_get_drvdata(pdev);
> > +	struct gdma_query_hwc_timeout_req req = {};
> > +	struct gdma_query_hwc_timeout_resp resp = {};
> > +	int err;
> > +
> > +	mana_gd_init_req_hdr(&req.hdr, GDMA_QUERY_HWC_TIMEOUT,
> > +			     sizeof(req), sizeof(resp));
> > +	req.timeout_ms = *timeout_val;
> > +	err = mana_gd_send_request(gc, sizeof(req), &req, sizeof(resp), &resp);
> > +	if (err || resp.hdr.status) {
> 
> I see this check almost in all callers to mana_gd_send_request(). It
> will be nice if mana_gd_send_request() would check status internally
> and return error.
> 
In a separate patch in future we can do that.
Thanks for the suggestion.
> > +		dev_err(gc->dev, "Failed to query timeout: %d, 0x%x\n", err,
> > +			resp.hdr.status);
> > +		return err ? err : -EPROTO;
> > +	}
> > +
> > +	*timeout_val = resp.timeout_ms;
> > +	dev_info(gc->dev, "Successfully changed the timeout value %u\n",
> > +		 *timeout_val);
> > +
> > +	return 0;
> > +}
> > +
> >  static int mana_gd_detect_devices(struct pci_dev *pdev)
> >  {
> >  	struct gdma_context *gc = pci_get_drvdata(pdev);
> > @@ -879,6 +903,7 @@ int mana_gd_verify_vf_version(struct pci_dev *pdev)
> >  	struct gdma_context *gc = pci_get_drvdata(pdev);
> >  	struct gdma_verify_ver_resp resp = {};
> >  	struct gdma_verify_ver_req req = {};
> > +	struct hw_channel_context *hwc = gc->hwc.driver_data;
> >  	int err;
> >  
> >  	mana_gd_init_req_hdr(&req.hdr, GDMA_VERIFY_VF_DRIVER_VERSION,
> > @@ -907,6 +932,8 @@ int mana_gd_verify_vf_version(struct pci_dev *pdev)
> >  			err, resp.hdr.status);
> >  		return err ? err : -EPROTO;
> >  	}
> > +	if (resp.pf_cap_flags1 & GDMA_DRV_CAP_FLAG_1_HWC_TIMEOUT_RECONFIG)
> > +		mana_gd_query_hwc_timeout(pdev, &hwc->hwc_timeout);
> >  
> >  	return 0;
> >  }
> > diff --git a/drivers/net/ethernet/microsoft/mana/hw_channel.c b/drivers/net/ethernet/microsoft/mana/hw_channel.c
> > index 9d1507eba5b9..f5980c26fd09 100644
> > --- a/drivers/net/ethernet/microsoft/mana/hw_channel.c
> > +++ b/drivers/net/ethernet/microsoft/mana/hw_channel.c
> > @@ -174,7 +174,25 @@ static void mana_hwc_init_event_handler(void *ctx, struct gdma_queue *q_self,
> >  		complete(&hwc->hwc_init_eqe_comp);
> >  		break;
> >  
> > +	case GDMA_EQE_HWC_SOC_RECONFIG_DATA:
> > +		type_data.as_uint32 = event->details[0];
> > +		type = type_data.type;
> > +		val = type_data.value;
> > +
> > +		switch (type) {
> > +		case HWC_DATA_CFG_HWC_TIMEOUT:
> > +			hwc->hwc_timeout = val;
> > +			break;
> > +
> > +		default:
> > +			dev_warn(hwc->dev, "Received unknown reconfig type %u\n", type);
> > +			break;
> > +		}
> > +
> > +		break;
> > +
> >  	default:
> > +		dev_warn(hwc->dev, "Received unknown gdma event %u\n", event->type);
> >  		/* Ignore unknown events, which should never happen. */
> >  		break;
> >  	}
> > @@ -704,6 +722,7 @@ int mana_hwc_create_channel(struct gdma_context *gc)
> >  	gd->pdid = INVALID_PDID;
> >  	gd->doorbell = INVALID_DOORBELL;
> >  
> > +	hwc->hwc_timeout = HW_CHANNEL_WAIT_RESOURCE_TIMEOUT_MS;
> >  	/* mana_hwc_init_queues() only creates the required data structures,
> >  	 * and doesn't touch the HWC device.
> >  	 */
> > @@ -770,6 +789,8 @@ void mana_hwc_destroy_channel(struct gdma_context *gc)
> >  	hwc->gdma_dev->doorbell = INVALID_DOORBELL;
> >  	hwc->gdma_dev->pdid = INVALID_PDID;
> >  
> > +	hwc->hwc_timeout = 0;
> > +
> >  	kfree(hwc);
> >  	gc->hwc.driver_data = NULL;
> >  	gc->hwc.gdma_context = NULL;
> > @@ -818,6 +839,7 @@ int mana_hwc_send_request(struct hw_channel_context *hwc, u32 req_len,
> >  		dest_vrq = hwc->pf_dest_vrq_id;
> >  		dest_vrcq = hwc->pf_dest_vrcq_id;
> >  	}
> > +	dev_err(hwc->dev, "HWC: timeout %u ms\n", hwc->hwc_timeout);
> >  
> >  	err = mana_hwc_post_tx_wqe(txq, tx_wr, dest_vrq, dest_vrcq, false);
> >  	if (err) {
> > @@ -825,7 +847,8 @@ int mana_hwc_send_request(struct hw_channel_context *hwc, u32 req_len,
> >  		goto out;
> >  	}
> >  
> > -	if (!wait_for_completion_timeout(&ctx->comp_event, 30 * HZ)) {
> > +	if (!wait_for_completion_timeout(&ctx->comp_event,
> > +					 (hwc->hwc_timeout / 1000) * HZ)) {
> >  		dev_err(hwc->dev, "HWC: Request timed out!\n");
> >  		err = -ETIMEDOUT;
> >  		goto out;
> > diff --git a/include/net/mana/gdma.h b/include/net/mana/gdma.h
> > index 96c120160f15..88b6ef7ce1a6 100644
> > --- a/include/net/mana/gdma.h
> > +++ b/include/net/mana/gdma.h
> > @@ -33,6 +33,7 @@ enum gdma_request_type {
> >  	GDMA_DESTROY_PD			= 30,
> >  	GDMA_CREATE_MR			= 31,
> >  	GDMA_DESTROY_MR			= 32,
> > +	GDMA_QUERY_HWC_TIMEOUT		= 84, /* 0x54 */
> >  };
> >  
> >  #define GDMA_RESOURCE_DOORBELL_PAGE	27
> > @@ -57,6 +58,8 @@ enum gdma_eqe_type {
> >  	GDMA_EQE_HWC_INIT_EQ_ID_DB	= 129,
> >  	GDMA_EQE_HWC_INIT_DATA		= 130,
> >  	GDMA_EQE_HWC_INIT_DONE		= 131,
> > +	GDMA_EQE_HWC_SOC_RECONFIG	= 132,
> > +	GDMA_EQE_HWC_SOC_RECONFIG_DATA	= 133,
> >  };
> >  
> >  enum {
> > @@ -531,10 +534,12 @@ enum {
> >   * so the driver is able to reliably support features like busy_poll.
> >   */
> >  #define GDMA_DRV_CAP_FLAG_1_NAPI_WKDONE_FIX BIT(2)
> > +#define GDMA_DRV_CAP_FLAG_1_HWC_TIMEOUT_RECONFIG BIT(3)
> >  
> >  #define GDMA_DRV_CAP_FLAGS1 \
> >  	(GDMA_DRV_CAP_FLAG_1_EQ_SHARING_MULTI_VPORT | \
> > -	 GDMA_DRV_CAP_FLAG_1_NAPI_WKDONE_FIX)
> > +	 GDMA_DRV_CAP_FLAG_1_NAPI_WKDONE_FIX | \
> > +	 GDMA_DRV_CAP_FLAG_1_HWC_TIMEOUT_RECONFIG)
> >  
> >  #define GDMA_DRV_CAP_FLAGS2 0
> >  
> > @@ -664,6 +669,19 @@ struct gdma_disable_queue_req {
> >  	u32 alloc_res_id_on_creation;
> >  }; /* HW DATA */
> >  
> > +/* GDMA_QUERY_HWC_TIMEOUT */
> > +struct gdma_query_hwc_timeout_req {
> > +	struct gdma_req_hdr hdr;
> > +	u32 timeout_ms;
> > +	u32 reserved;
> > +};
> > +
> > +struct gdma_query_hwc_timeout_resp {
> > +	struct gdma_resp_hdr hdr;
> > +	u32 timeout_ms;
> > +	u32 reserved;
> > +};
> > +
> >  enum atb_page_size {
> >  	ATB_PAGE_SIZE_4K,
> >  	ATB_PAGE_SIZE_8K,
> > diff --git a/include/net/mana/hw_channel.h b/include/net/mana/hw_channel.h
> > index 6a757a6e2732..3d3b5c881bc1 100644
> > --- a/include/net/mana/hw_channel.h
> > +++ b/include/net/mana/hw_channel.h
> > @@ -23,6 +23,10 @@
> >  #define HWC_INIT_DATA_PF_DEST_RQ_ID	10
> >  #define HWC_INIT_DATA_PF_DEST_CQ_ID	11
> >  
> > +#define HWC_DATA_CFG_HWC_TIMEOUT 1
> > +
> > +#define HW_CHANNEL_WAIT_RESOURCE_TIMEOUT_MS 30000
> > +
> >  /* Structures labeled with "HW DATA" are exchanged with the hardware. All of
> >   * them are naturally aligned and hence don't need __packed.
> >   */
> > @@ -182,6 +186,7 @@ struct hw_channel_context {
> >  
> >  	u32 pf_dest_vrq_id;
> >  	u32 pf_dest_vrcq_id;
> > +	u32 hwc_timeout;
> >  
> >  	struct hwc_caller_ctx *caller_ctx;
> >  };
> > -- 
> > 2.34.1
> >