提交 060e3522 编写于 作者: J Jeff Dike 提交者: Linus Torvalds

[PATCH] uml: Delay loop cleanups

This patch cleans up the delay implementations a bit, makes the loops
unoptimizable, and exports __udelay and __const_udelay.
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
上级 13479d52
#include "linux/delay.h" #include <linux/module.h>
#include "asm/param.h" #include <linux/kernel.h>
#include <linux/delay.h>
#include <asm/param.h>
void __delay(unsigned long time) void __delay(unsigned long time)
{ {
...@@ -20,13 +22,19 @@ void __udelay(unsigned long usecs) ...@@ -20,13 +22,19 @@ void __udelay(unsigned long usecs)
int i, n; int i, n;
n = (loops_per_jiffy * HZ * usecs) / MILLION; n = (loops_per_jiffy * HZ * usecs) / MILLION;
for(i=0;i<n;i++) ; for(i=0;i<n;i++)
cpu_relax();
} }
EXPORT_SYMBOL(__udelay);
void __const_udelay(unsigned long usecs) void __const_udelay(unsigned long usecs)
{ {
int i, n; int i, n;
n = (loops_per_jiffy * HZ * usecs) / MILLION; n = (loops_per_jiffy * HZ * usecs) / MILLION;
for(i=0;i<n;i++) ; for(i=0;i<n;i++)
cpu_relax();
} }
EXPORT_SYMBOL(__const_udelay);
...@@ -5,40 +5,37 @@ ...@@ -5,40 +5,37 @@
* Licensed under the GPL * Licensed under the GPL
*/ */
#include "linux/delay.h" #include <linux/module.h>
#include "asm/processor.h" #include <linux/delay.h>
#include "asm/param.h" #include <asm/processor.h>
#include <asm/param.h>
void __delay(unsigned long loops) void __delay(unsigned long loops)
{ {
unsigned long i; unsigned long i;
for(i = 0; i < loops; i++) ; for(i = 0; i < loops; i++)
cpu_relax();
} }
void __udelay(unsigned long usecs) void __udelay(unsigned long usecs)
{ {
int i, n; unsigned long i, n;
n = (loops_per_jiffy * HZ * usecs) / MILLION; n = (loops_per_jiffy * HZ * usecs) / MILLION;
for(i=0;i<n;i++) ; for(i=0;i<n;i++)
cpu_relax();
} }
EXPORT_SYMBOL(__udelay);
void __const_udelay(unsigned long usecs) void __const_udelay(unsigned long usecs)
{ {
int i, n; unsigned long i, n;
n = (loops_per_jiffy * HZ * usecs) / MILLION; n = (loops_per_jiffy * HZ * usecs) / MILLION;
for(i=0;i<n;i++) ; for(i=0;i<n;i++)
cpu_relax();
} }
/* EXPORT_SYMBOL(__const_udelay);
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/
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