pci/aspm: Remove CONFIG_PCIEASPM_DEBUG

Currently, the linux kernel disables ASPM when a device is
removed from the kernel. But it is not enabled again when
a new device is added on that slot even if it was originally
enabled (by the BIOS) when the system booted up (assuming
POLICY_DEFAULT).

This was earlier discussed here:
https://www.spinics.net/lists/linux-pci/msg60212.html

And some suggestions from Bjorn here:
https://www.spinics.net/lists/linux-pci/msg60541.html

This patch picks up one of the suggestion, to remove the
CONFIG_PCIEASPM_DEBUG and thus make the code always
avilable. This provides control to userspace to control
ASPM on a per slot / device basis using sysfs interface.

Signed-off-by: Rajat Jain <rajatja@google.com>
---
 drivers/pci/pci.h        | 5 -----
 drivers/pci/pcie/Kconfig | 8 --------
 drivers/pci/pcie/aspm.c  | 2 --
 3 files changed, 15 deletions(-)

On 2018-05-09 00:01, Rajat Jain wrote:
> Currently, the linux kernel disables ASPM when a device is
> removed from the kernel. But it is not enabled again when
> a new device is added on that slot even if it was originally
> enabled (by the BIOS) when the system booted up (assuming
> POLICY_DEFAULT).
> 
> This was earlier discussed here:
> https://www.spinics.net/lists/linux-pci/msg60212.html
> 
> And some suggestions from Bjorn here:
> https://www.spinics.net/lists/linux-pci/msg60541.html
> 
> This patch picks up one of the suggestion, to remove the
> CONFIG_PCIEASPM_DEBUG and thus make the code always
> avilable. This provides control to userspace to control
> ASPM on a per slot / device basis using sysfs interface.
> 
> Signed-off-by: Rajat Jain <rajatja@google.com>

Reviewed-by: Sinan Kaya <okaya@codeaurora.org>


> ---
>  drivers/pci/pci.h        | 5 -----
>  drivers/pci/pcie/Kconfig | 8 --------
>  drivers/pci/pcie/aspm.c  | 2 --
>  3 files changed, 15 deletions(-)
> 
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index 023f7cf25bff..383d92a6b0fb 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -365,13 +365,8 @@ static inline void
> pcie_aspm_pm_state_change(struct pci_dev *pdev) { }
>  static inline void pcie_aspm_powersave_config_link(struct pci_dev 
> *pdev) { }
>  #endif
> 
> -#ifdef CONFIG_PCIEASPM_DEBUG
>  void pcie_aspm_create_sysfs_dev_files(struct pci_dev *pdev);
>  void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev);
> -#else
> -static inline void pcie_aspm_create_sysfs_dev_files(struct pci_dev 
> *pdev) { }
> -static inline void pcie_aspm_remove_sysfs_dev_files(struct pci_dev 
> *pdev) { }
> -#endif
> 
>  #ifdef CONFIG_PCIE_PTM
>  void pci_ptm_init(struct pci_dev *dev);
> diff --git a/drivers/pci/pcie/Kconfig b/drivers/pci/pcie/Kconfig
> index b12e28b3d8f9..089b9f559d88 100644
> --- a/drivers/pci/pcie/Kconfig
> +++ b/drivers/pci/pcie/Kconfig
> @@ -46,14 +46,6 @@ config PCIEASPM
> 
>  	  When in doubt, say Y.
> 
> -config PCIEASPM_DEBUG
> -	bool "Debug PCI Express ASPM"
> -	depends on PCIEASPM
> -	default n
> -	help
> -	  This enables PCI Express ASPM debug support. It will add per-device
> -	  interface to control ASPM.
> -
>  choice
>  	prompt "Default ASPM policy"
>  	default PCIEASPM_DEFAULT
> diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
> index c687c817b47d..8ffc13d42baa 100644
> --- a/drivers/pci/pcie/aspm.c
> +++ b/drivers/pci/pcie/aspm.c
> @@ -1161,7 +1161,6 @@ static int pcie_aspm_get_policy(char *buffer,
> const struct kernel_param *kp)
>  module_param_call(policy, pcie_aspm_set_policy, pcie_aspm_get_policy,
>  	NULL, 0644);
> 
> -#ifdef CONFIG_PCIEASPM_DEBUG
>  static ssize_t link_state_show(struct device *dev,
>  		struct device_attribute *attr,
>  		char *buf)
> @@ -1264,7 +1263,6 @@ void pcie_aspm_remove_sysfs_dev_files(struct
> pci_dev *pdev)
>  		sysfs_remove_file_from_group(&pdev->dev.kobj,
>  			&dev_attr_clk_ctl.attr, power_group);
>  }
> -#endif
> 
>  static int __init pcie_aspm_disable(char *str)
>  {

Hi Rajat,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on pci/next]
[also build test ERROR on v4.17-rc4 next-20180508]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Rajat-Jain/pci-aspm-Remove-CONFIG_PCIEASPM_DEBUG/20180509-161750
base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: i386-alldefconfig (attached as .config)
compiler: gcc-7 (Debian 7.3.0-16) 7.3.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All errors (new ones prefixed by >>):

   drivers/pci/pci-sysfs.o: In function `pci_create_sysfs_dev_files':
>> pci-sysfs.c:(.text+0x19b0): undefined reference to `pcie_aspm_create_sysfs_dev_files'
>> pci-sysfs.c:(.text+0x1a16): undefined reference to `pcie_aspm_remove_sysfs_dev_files'
   drivers/pci/pci-sysfs.o: In function `pci_remove_sysfs_dev_files':
   pci-sysfs.c:(.text+0x1af6): undefined reference to `pcie_aspm_remove_sysfs_dev_files'

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation