[PATCH] Make udev/udevstart be one binary

Hi,

The following patch makes udev/udevstart be a common binary.  First,
doing this grows udev by a total of 1.8kB (ppc32, stripped) whereas
udevstart by itself is 6.4kB.  I know you mentioned being able to
replace udevstart with a script, but at 1.8kB I don't think it'll be
easy to beat this with size there.  Next, the following are by-eye
timings of before, after, and with devfs on a slow, but still usable
embedded platform (config stripped down to more-or-less bare for
ramdisk):
-- Embedded Planet RPX LITE, 64Mhz MPC 823e --
devfs         : 15.333s, 15.253s, 14.988s (15.191s avg)
udev-pristine : 18.675s, 18.079s, 18.418s (18.390s avg)
udev-multi    : 14.587s, 14.747s, 14.868s (14.734s avg)

The patch ends up being rather large to add this, as in doing so I ended
up making all refs (that I hit..) to devpath/subsystem be marked as
'const'.


Signed-off-by: Tom Rini <trini@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

1 files changed, 8 insertions, 39 deletions

diff --git a/udevstart.c b/udevstart.c
index 3ecfd4cb61..d94c9501c9 100644
--- a/udevstart.c
+++ b/udevstart.c
@@ -36,25 +36,12 @@
 #include "logging.h"
 #include "udev_lib.h"
 #include "list.h"
-
-
-#ifdef LOG
-unsigned char logname[LOGNAME_SIZE];
-void log_message(int level, const char *format, ...)
-{
-	va_list args;
-
-	va_start(args, format);
-	vsyslog(level, format, args);
-	va_end(args);
-}
-#endif
+#include "udev.h"
 
 
 #define MAX_PATHLEN		1024
 #define SYSBLOCK		"/sys/block"
 #define SYSCLASS		"/sys/class"
-#define UDEV_BIN		"/sbin/udev"
 
 struct device {
 	struct list_head list;
@@ -88,28 +75,13 @@ static int device_list_insert(char *path, char *subsystem, struct list_head *dev
 
 static void udev_exec(const char *path, const char* subsystem)
 {
-	pid_t pid;
-	char action[] = "ACTION=add";
-	char devpath[MAX_PATHLEN];
-	char nosleep[] = "UDEV_NO_SLEEP=1";
-	char *env[] = { action, devpath, nosleep, NULL };
-
-	strcpy(devpath, "DEVPATH=");
-	strfieldcat(devpath, path);
-
-	pid = fork();
-	switch (pid) {
-	case 0:
-		/* child */
-		execle(UDEV_BIN, "udev", subsystem, NULL, env);
-		dbg("exec of child failed");
+	/* Setup env variables. */
+	setenv("UDEV_NO_SLEEP", "1", 1);
+
+	/* Now call __udev_hotplug(). */
+	if (__udev_hotplug("add", path, subsystem)) {
+		dbg("Calling of udev_hotplug failed");
 		exit(1);
-		break;
-	case -1:
-		dbg("fork of child failed");
-		break;
-	default:
-		wait(NULL);
 	}
 }
 
@@ -267,12 +239,9 @@ static void udev_scan_class(void)
 	exec_list(&device_list);
 }
 
-int main(int argc, char *argv[], char *envp[])
+int udev_start(void)
 {
-	init_logging("udevstart");
-
 	udev_scan_class();
 	udev_scan_block();
-
 	return 0;
 }