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Message-ID: <c200a544-31fe-b660-82bb-4bbed5acf135@ti.com>
Date:   Thu, 25 Aug 2022 15:47:10 +0530
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Subject: Re: [PATCH 2/2] PCI: endpoint: Use link_up() callback in place of
 LINK_UP notifier
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To:     Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>,
        <lpieralisi@kernel.org>, <bhelgaas@google.com>
CC:     <kw@linux.com>, <robh@kernel.org>, <vidyas@nvidia.com>,
        <linux-pci@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20220811094237.77632-1-manivannan.sadhasivam@linaro.org>
 <20220811094237.77632-3-manivannan.sadhasivam@linaro.org>
From:   Kishon Vijay Abraham I <kishon@ti.com>
In-Reply-To: <20220811094237.77632-3-manivannan.sadhasivam@linaro.org>
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Hi Mani,

On 11/08/22 15:12, Manivannan Sadhasivam wrote:
> As a part of the transition towards callback mechanism for signalling the
> events from EPC to EPF, let's use the link_up() callback in the place of
> the LINK_UP notifier. This also removes the notifier support completely
> from the PCI endpoint framework.
> 
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>  drivers/pci/endpoint/functions/pci-epf-test.c | 33 ++++++-------------
>  drivers/pci/endpoint/pci-epc-core.c           |  8 +++--
>  include/linux/pci-epc.h                       |  8 -----
>  include/linux/pci-epf.h                       |  8 ++---
>  4 files changed, 18 insertions(+), 39 deletions(-)
> 

.
.
<snip>
.
.
> diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
> index 805f3d64f93b..a51ba9f158c3 100644
> --- a/drivers/pci/endpoint/pci-epc-core.c
> +++ b/drivers/pci/endpoint/pci-epc-core.c
> @@ -690,10 +690,15 @@ EXPORT_SYMBOL_GPL(pci_epc_remove_epf);
>   */
>  void pci_epc_linkup(struct pci_epc *epc)
>  {
> +	struct pci_epf *epf;
> +
>  	if (!epc || IS_ERR(epc))
>  		return;
>  
> -	atomic_notifier_call_chain(&epc->notifier, LINK_UP, NULL);
> +	list_for_each_entry(epf, &epc->pci_epf, list) {
> +		if (epf->event_ops->link_up)
> +			epf->event_ops->link_up(epf);
> +	}

how do you ensure there is no race while invoking the call back
functions during add/remove of epf?

Thanks,
Kishon