Re: [PATCH 1/1] powerpc: Drop superfluous pci_dev_is_added() calls

From: Bjorn Helgaas <helgaas@kernel.org>
To: Niklas Schnelle <schnelle@linux.ibm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Oliver O'Halloran <oohall@gmail.com>,
	linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-s390@vger.kernel.org, linux-arch@vger.kernel.org,
	linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH 1/1] powerpc: Drop superfluous pci_dev_is_added() calls
Date: Tue, 14 Sep 2021 14:31:30 -0500	[thread overview]
Message-ID: <20210914193130.GA1447657@bjorn-Precision-5520> (raw)
In-Reply-To: <20210910141940.2598035-2-schnelle@linux.ibm.com>

On Fri, Sep 10, 2021 at 04:19:40PM +0200, Niklas Schnelle wrote:
> On powerpc, pci_dev_is_added() is called as part of SR-IOV fixups
> that are done under pcibios_add_device() which in turn is only called in
> pci_device_add() whih is called when a PCI device is scanned.
> 
> Now pci_dev_assign_added() is called in pci_bus_add_device() which is
> only called after scanning the device. Thus pci_dev_is_added() is always
> false and can be dropped.
> 
> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>

Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>

This doesn't touch the PCI core, so maybe makes sense for you to take
it, Michael?  But let me know if you think otherwise.

Thanks a lot for cleaning this up, Niklas.

> ---
>  arch/powerpc/platforms/powernv/pci-sriov.c | 6 ------
>  arch/powerpc/platforms/pseries/setup.c     | 3 +--
>  2 files changed, 1 insertion(+), 8 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/powernv/pci-sriov.c b/arch/powerpc/platforms/powernv/pci-sriov.c
> index 28aac933a439..deddbb233fde 100644
> --- a/arch/powerpc/platforms/powernv/pci-sriov.c
> +++ b/arch/powerpc/platforms/powernv/pci-sriov.c
> @@ -9,9 +9,6 @@
>  
>  #include "pci.h"
>  
> -/* for pci_dev_is_added() */
> -#include "../../../../drivers/pci/pci.h"
> -
>  /*
>   * The majority of the complexity in supporting SR-IOV on PowerNV comes from
>   * the need to put the MMIO space for each VF into a separate PE. Internally
> @@ -228,9 +225,6 @@ static void pnv_pci_ioda_fixup_iov_resources(struct pci_dev *pdev)
>  
>  void pnv_pci_ioda_fixup_iov(struct pci_dev *pdev)
>  {
> -	if (WARN_ON(pci_dev_is_added(pdev)))
> -		return;
> -
>  	if (pdev->is_virtfn) {
>  		struct pnv_ioda_pe *pe = pnv_ioda_get_pe(pdev);
>  
> diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
> index f79126f16258..2188054470c1 100644
> --- a/arch/powerpc/platforms/pseries/setup.c
> +++ b/arch/powerpc/platforms/pseries/setup.c
> @@ -74,7 +74,6 @@
>  #include <asm/hvconsole.h>
>  
>  #include "pseries.h"
> -#include "../../../../drivers/pci/pci.h"
>  
>  DEFINE_STATIC_KEY_FALSE(shared_processor);
>  EXPORT_SYMBOL(shared_processor);
> @@ -750,7 +749,7 @@ static void pseries_pci_fixup_iov_resources(struct pci_dev *pdev)
>  	const int *indexes;
>  	struct device_node *dn = pci_device_to_OF_node(pdev);
>  
> -	if (!pdev->is_physfn || pci_dev_is_added(pdev))
> +	if (!pdev->is_physfn)
>  		return;
>  	/*Firmware must support open sriov otherwise dont configure*/
>  	indexes = of_get_property(dn, "ibm,open-sriov-vf-bar-info", NULL);
> -- 
> 2.25.1
> 