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arch/x86/kernel/io_apic_{64,32}.c: use time_before
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The functions time_before, time_before_eq, time_after, and time_after_eq
are more robust for comparing jiffies against other values.

A simplified version of the semantic patch making this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@ change_compare_np @
expression E;
@@

(
- jiffies <= E
+ time_before_eq(jiffies,E)
|
- jiffies >= E
+ time_after_eq(jiffies,E)
|
- jiffies < E
+ time_before(jiffies,E)
|
- jiffies > E
+ time_after(jiffies,E)
)

@ include depends on change_compare_np @
@@

#include <linux/jiffies.h>

@ no_include depends on !include && change_compare_np @
@@

  #include <linux/...>
+ #include <linux/jiffies.h>
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Julia Lawall authored and Ingo Molnar committed Jan 30, 2008
1 parent 4f2479f commit 1d16b53
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Showing 2 changed files with 5 additions and 3 deletions.
5 changes: 3 additions & 2 deletions arch/x86/kernel/io_apic_32.c
Original file line number Diff line number Diff line change
Expand Up @@ -35,6 +35,7 @@
#include <linux/htirq.h>
#include <linux/freezer.h>
#include <linux/kthread.h>
#include <linux/jiffies.h> /* time_after() */

#include <asm/io.h>
#include <asm/smp.h>
Expand Down Expand Up @@ -349,7 +350,7 @@ static void set_ioapic_affinity_irq(unsigned int irq, cpumask_t cpumask)
# include <asm/processor.h> /* kernel_thread() */
# include <linux/kernel_stat.h> /* kstat */
# include <linux/slab.h> /* kmalloc() */
# include <linux/timer.h> /* time_after() */
# include <linux/timer.h>

#define IRQBALANCE_CHECK_ARCH -999
#define MAX_BALANCED_IRQ_INTERVAL (5*HZ)
Expand Down Expand Up @@ -1898,7 +1899,7 @@ static int __init timer_irq_works(void)
* might have cached one ExtINT interrupt. Finally, at
* least one tick may be lost due to delays.
*/
if (jiffies - t1 > 4)
if (time_after(jiffies, t1 + 4))
return 1;

return 0;
Expand Down
3 changes: 2 additions & 1 deletion arch/x86/kernel/io_apic_64.c
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,7 @@
#include <linux/msi.h>
#include <linux/htirq.h>
#include <linux/dmar.h>
#include <linux/jiffies.h>
#ifdef CONFIG_ACPI
#include <acpi/acpi_bus.h>
#endif
Expand Down Expand Up @@ -1299,7 +1300,7 @@ static int __init timer_irq_works(void)
*/

/* jiffies wrap? */
if (jiffies - t1 > 4)
if (time_after(jiffies, t1 + 4))
return 1;
return 0;
}
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