Re: [PATCH 3/4] perf/dwc_pcie: Always register for PCIe bus notifier

[Yicong Yang]

On 2024/7/31 12:23, Krishna chaitanya chundru wrote:
> When the PCIe devices are discovered late, the driver can't find
> the PCIe devices and returns in the init without registering with
> the bus notifier. Due to that the devices which are discovered late
> the driver can't register for this.
> 
> Register for bus notifier even if the device is not found in init.
> 
> Fixes: af9597adc2f1 ("drivers/perf: add DesignWare PCIe PMU driver")
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@xxxxxxxxxxx>
> ---
>  drivers/perf/dwc_pcie_pmu.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/perf/dwc_pcie_pmu.c b/drivers/perf/dwc_pcie_pmu.c
> index c115348b8d53..aa1010b44bcb 100644
> --- a/drivers/perf/dwc_pcie_pmu.c
> +++ b/drivers/perf/dwc_pcie_pmu.c
> @@ -741,8 +741,6 @@ static int __init dwc_pcie_pmu_init(void)
>  
>  		found = true;
>  	}
> -	if (!found)
> -		return -ENODEV;
>  
>  	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
>  				      "perf/dwc_pcie_pmu:online",
> @@ -753,9 +751,11 @@ static int __init dwc_pcie_pmu_init(void)
>  
>  	dwc_pcie_pmu_hp_state = ret;
>  
> -	ret = platform_driver_register(&dwc_pcie_pmu_driver);
> -	if (ret)
> -		goto platform_driver_register_err;
> +	if (!found) {
> +		ret = platform_driver_register(&dwc_pcie_pmu_driver);
> +		if (ret)
> +			goto platform_driver_register_err;
> +	}
> 

This doesn't match the commit.

If any device is found at this stage, we cannot use them since you don't
register a driver.

>  	ret = bus_register_notifier(&pci_bus_type, &dwc_pcie_pmu_nb);
>  	if (ret)
>