These variables cause false sharing in some circumstances. However, they
are just small pointers and 4 byte ints. So this patch would result in
some wastage of memory since each of those pointers then would occupy a
whole cache line.
Do we have any provisions for this situation? Or do we need a new section
for mostly_readonly?
Signed-off-by: Alok N Kataria <[email protected]>
Signed-off-by: Shai Fultheim <[email protected]>
Signed-off-by: Christoph Lameter <[email protected]>
Index: linux-2.6.12-rc6-mm1/arch/i386/kernel/time.c
===================================================================
--- linux-2.6.12-rc6-mm1.orig/arch/i386/kernel/time.c 2005-06-07 11:15:43.000000000 -0700
+++ linux-2.6.12-rc6-mm1/arch/i386/kernel/time.c 2005-06-07 11:27:57.000000000 -0700
@@ -88,7 +88,7 @@ EXPORT_SYMBOL(rtc_lock);
DEFINE_SPINLOCK(i8253_lock);
EXPORT_SYMBOL(i8253_lock);
-struct timer_opts *cur_timer = &timer_none;
+struct timer_opts *cur_timer __cacheline_aligned_mostly_readonly = &timer_none;
/*
* This is a special lock that is owned by the CPU and holds the index
Index: linux-2.6.12-rc6-mm1/arch/i386/kernel/timers/timer_hpet.c
===================================================================
--- linux-2.6.12-rc6-mm1.orig/arch/i386/kernel/timers/timer_hpet.c 2005-06-07 11:26:36.000000000 -0700
+++ linux-2.6.12-rc6-mm1/arch/i386/kernel/timers/timer_hpet.c 2005-06-07 11:27:57.000000000 -0700
@@ -18,7 +18,9 @@
#include "mach_timer.h"
#include <asm/hpet.h>
-static unsigned long hpet_usec_quotient; /* convert hpet clks to usec */
+static unsigned long hpet_usec_quotient __cacheline_aligned_mostly_readonly;
+ /* convert hpet clks to usec */
+
static unsigned long tsc_hpet_quotient; /* convert tsc to hpet clks */
static unsigned long hpet_last; /* hpet counter value at last tick*/
static unsigned long last_tsc_low; /* lsb 32 bits of Time Stamp Counter */
Index: linux-2.6.12-rc6-mm1/drivers/char/random.c
===================================================================
--- linux-2.6.12-rc6-mm1.orig/drivers/char/random.c 2005-06-07 11:13:41.000000000 -0700
+++ linux-2.6.12-rc6-mm1/drivers/char/random.c 2005-06-07 11:27:57.000000000 -0700
@@ -271,7 +271,8 @@ static int random_write_wakeup_thresh =
* samples to avoid wasting CPU time and reduce lock contention.
*/
-static int trickle_thresh = INPUT_POOL_WORDS * 28;
+static int trickle_thresh __cacheline_aligned_mostly_readonly =
+ INPUT_POOL_WORDS * 28;
static DEFINE_PER_CPU(int, trickle_count) = 0;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
