libpciaccess/libpciaccess-fd-cache.patch
Adam Jackson 38ab561713 - libpciaccess-fd-cache.patch: Cache sysfs PCI config space file
descriptors for great boot speed justice.
2008-01-23 18:45:55 +00:00

144 lines
3.5 KiB
Diff

diff -up libpciaccess-20071031/src/linux_sysfs.c.cache libpciaccess-20071031/src/linux_sysfs.c
--- libpciaccess-20071031/src/linux_sysfs.c.cache 2007-10-23 09:19:36.000000000 -0400
+++ libpciaccess-20071031/src/linux_sysfs.c 2008-01-22 19:23:12.000000000 -0500
@@ -55,6 +55,8 @@
#include "pciaccess_private.h"
#include "linux_devmem.h"
+static void pci_device_linux_sysfs_destroy( void );
+
static int pci_device_linux_sysfs_read_rom( struct pci_device * dev,
void * buffer );
@@ -74,7 +76,7 @@
pciaddr_t * bytes_wrtten );
static const struct pci_system_methods linux_sysfs_methods = {
- .destroy = NULL,
+ .destroy = pci_device_linux_sysfs_destroy,
.destroy_device = NULL,
.read_rom = pci_device_linux_sysfs_read_rom,
.probe = pci_device_linux_sysfs_probe,
@@ -362,6 +364,53 @@
return err;
}
+static struct pci_device *last_config_dev = NULL;
+static int config_fd = -1;
+
+static void
+pci_device_linux_sysfs_destroy( void )
+{
+ if (config_fd != -1)
+ close( config_fd );
+}
+
+static int
+open_config_fd( struct pci_device * dev, int flags )
+{
+ int fd;
+ char name[256];
+
+ /* Each device has a directory under sysfs. Within that directory there
+ * is a file named "config". This file used to access the PCI config
+ * space. It is used here to obtain most of the information about the
+ * device.
+ */
+
+ if ( last_config_dev != dev ) {
+ if ( config_fd != -1 ) {
+ close( config_fd );
+ last_config_dev = NULL;
+ }
+
+ snprintf( name, 255, "%s/%04x:%02x:%02x.%1u/config",
+ SYS_BUS_PCI,
+ dev->domain,
+ dev->bus,
+ dev->dev,
+ dev->func );
+
+ fd = open( name, flags );
+ if ( fd == -1 ) {
+ return -1;
+ }
+ config_fd = fd;
+ last_config_dev = dev;
+ } else {
+ fd = config_fd;
+ }
+
+ return fd;
+}
static int
pci_device_linux_sysfs_read( struct pci_device * dev, void * data,
@@ -378,23 +427,9 @@
*bytes_read = 0;
}
- /* Each device has a directory under sysfs. Within that directory there
- * is a file named "config". This file used to access the PCI config
- * space. It is used here to obtain most of the information about the
- * device.
- */
- snprintf( name, 255, "%s/%04x:%02x:%02x.%1u/config",
- SYS_BUS_PCI,
- dev->domain,
- dev->bus,
- dev->dev,
- dev->func );
-
- fd = open( name, O_RDONLY );
- if ( fd == -1 ) {
+ fd = open_config_fd( dev, O_RDONLY );
+ if ( fd == -1 )
return errno;
- }
-
while ( temp_size > 0 ) {
const ssize_t bytes = pread64( fd, data_bytes, temp_size, offset );
@@ -416,7 +451,6 @@
*bytes_read = size - temp_size;
}
- close( fd );
return err;
}
@@ -436,23 +470,9 @@
*bytes_written = 0;
}
- /* Each device has a directory under sysfs. Within that directory there
- * is a file named "config". This file used to access the PCI config
- * space. It is used here to obtain most of the information about the
- * device.
- */
- snprintf( name, 255, "%s/%04x:%02x:%02x.%1u/config",
- SYS_BUS_PCI,
- dev->domain,
- dev->bus,
- dev->dev,
- dev->func );
-
- fd = open( name, O_WRONLY );
- if ( fd == -1 ) {
+ fd = open_config_fd( dev, O_WRONLY );
+ if ( fd == -1 )
return errno;
- }
-
while ( temp_size > 0 ) {
const ssize_t bytes = pwrite64( fd, data_bytes, temp_size, offset );
@@ -474,7 +494,6 @@
*bytes_written = size - temp_size;
}
- close( fd );
return err;
}