PCI: Add include guard to include/linux/pci_ids.h

Adding an include guard frees the preprocessor from reparsing over 2600
#defines in the cases where pci_ids.h is somehow included more than once.
This gives a tiny-but-measurable performance improvement when compiling
such files.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
index 7fa31731c854..6ed0bb73a864 100644
--- a/include/linux/pci_ids.h
+++ b/include/linux/pci_ids.h
@@ -6,6 +6,8 @@
  *      Do not add new entries to this file unless the definitions
  *      are shared between multiple drivers.
  */
+#ifndef _LINUX_PCI_IDS_H
+#define _LINUX_PCI_IDS_H
 
 /* Device classes and subclasses */
 
@@ -2968,3 +2970,5 @@
 #define PCI_DEVICE_ID_XEN_PLATFORM      0x0001
 
 #define PCI_VENDOR_ID_OCZ               0x1b85
+
+#endif /* _LINUX_PCI_IDS_H */