Re: [GIT PATCH] PCI patches for 2.6.24

From: Andrew Morton
Date: Fri Feb 01 2008 - 19:42:35 EST


On Fri, 1 Feb 2008 15:11:47 -0800
Greg KH <gregkh@xxxxxxx> wrote:

> PCI: PCIE ASPM support

drivers/built-in.o: In function `pci_scan_slot':
drivers/pci/probe.c:1016: undefined reference to `pcie_aspm_init_link_state'
drivers/built-in.o: In function `pci_stop_dev':
drivers/pci/remove.c:36: undefined reference to `pcie_aspm_exit_link_state'
drivers/built-in.o: In function `pci_set_power_state':
drivers/pci/pci.c:524: undefined reference to `pcie_aspm_pm_state_change'
make: *** [.tmp_vmlinux1] Error 1

http://userweb.kernel.org/~akpm/config-vmm.txt


Needs this, I guess:


--- a/drivers/pci/pcie/Kconfig~fix-gregkh-pci-pci-pcie-aspm-support
+++ a/drivers/pci/pcie/Kconfig
@@ -32,7 +32,7 @@ source "drivers/pci/pcie/aer/Kconfig"
#
config PCIEASPM
bool "PCI Express ASPM support(Experimental)"
- depends on PCI && EXPERIMENTAL
+ depends on PCI && EXPERIMENTAL && PCIEPORTBUS
default y
help
This enables PCI Express ASPM (Active State Power Management) and
_


Also, that ASPM patch unnecessarily adds a pile of macros:

+#ifdef CONFIG_PCIEASPM
+extern void pcie_aspm_init_link_state(struct pci_dev *pdev);
+extern void pcie_aspm_exit_link_state(struct pci_dev *pdev);
+extern void pcie_aspm_pm_state_change(struct pci_dev *pdev);
+extern void pci_disable_link_state(struct pci_dev *pdev, int state);
+#else
+#define pcie_aspm_init_link_state(pdev) do {} while (0)
+#define pcie_aspm_exit_link_state(pdev) do {} while (0)
+#define pcie_aspm_pm_state_change(pdev) do {} while (0)
+#define pci_disable_link_state(pdev, state) do {} while (0)
+#endif

Please don't do this.

A static inline function is cleaner and provides typechecking. It also
provides an access to the caller's argument and can avoid unused-varaiable
warnings.

The only reason to use a macro in this situation is if the caller's
argument is for some reason not defined if !CONFIG_PCIEASPM.

Greg, please check for this in your reviewing - reject macros *by default*.
They are inferior.

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