[PATCH] w1: get rid of the potential problems with atomic operations.
ChangeSet 1.2085, 2005/03/02 16:59:41-08:00, [EMAIL PROTECTED]
[PATCH] w1: get rid of the potential problems with atomic operations.
Get rid of the potential problems with atomic operations.
According to upcoming atomic_ops.txt by David Miller and Anton Blanchard
some archs may reoder atomic operations with nonatomic, since
the former are always visible but the latter are not, this can lead
to unpredicted behaviour.
Signed-off-by: Evgeniy Polyakov <[EMAIL PROTECTED]>
Signed-off-by: Greg Kroah-Hartman <[EMAIL PROTECTED]>
drivers/w1/w1_family.c |2 ++
drivers/w1/w1_therm.c |2 ++
2 files changed, 4 insertions(+)
diff -Nru a/drivers/w1/w1_family.c b/drivers/w1/w1_family.c
--- a/drivers/w1/w1_family.c2005-03-04 12:37:51 -08:00
+++ b/drivers/w1/w1_family.c2005-03-04 12:37:51 -08:00
@@ -138,7 +138,9 @@
void __w1_family_get(struct w1_family *f)
{
+ smp_mb__before_atomic_inc();
atomic_inc(>refcnt);
+ smp_mb__after_atomic_inc();
}
EXPORT_SYMBOL(w1_family_get);
diff -Nru a/drivers/w1/w1_therm.c b/drivers/w1/w1_therm.c
--- a/drivers/w1/w1_therm.c 2005-03-04 12:37:51 -08:00
+++ b/drivers/w1/w1_therm.c 2005-03-04 12:37:51 -08:00
@@ -104,6 +104,7 @@
int i, max_trying = 10;
atomic_inc(>refcnt);
+ smp_mb__after_atomic_inc();
if (down_interruptible(>master->mutex)) {
count = 0;
goto out_dec;
@@ -179,6 +180,7 @@
out:
up(>mutex);
out_dec:
+ smp_mb__before_atomic_inc();
atomic_dec(>refcnt);
return count;
-
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[PATCH] w1: get rid of the potential problems with atomic operations.
ChangeSet 1.2085, 2005/03/02 16:59:41-08:00, [EMAIL PROTECTED]
[PATCH] w1: get rid of the potential problems with atomic operations.
Get rid of the potential problems with atomic operations.
According to upcoming atomic_ops.txt by David Miller and Anton Blanchard
some archs may reoder atomic operations with nonatomic, since
the former are always visible but the latter are not, this can lead
to unpredicted behaviour.
Signed-off-by: Evgeniy Polyakov [EMAIL PROTECTED]
Signed-off-by: Greg Kroah-Hartman [EMAIL PROTECTED]
drivers/w1/w1_family.c |2 ++
drivers/w1/w1_therm.c |2 ++
2 files changed, 4 insertions(+)
diff -Nru a/drivers/w1/w1_family.c b/drivers/w1/w1_family.c
--- a/drivers/w1/w1_family.c2005-03-04 12:37:51 -08:00
+++ b/drivers/w1/w1_family.c2005-03-04 12:37:51 -08:00
@@ -138,7 +138,9 @@
void __w1_family_get(struct w1_family *f)
{
+ smp_mb__before_atomic_inc();
atomic_inc(f-refcnt);
+ smp_mb__after_atomic_inc();
}
EXPORT_SYMBOL(w1_family_get);
diff -Nru a/drivers/w1/w1_therm.c b/drivers/w1/w1_therm.c
--- a/drivers/w1/w1_therm.c 2005-03-04 12:37:51 -08:00
+++ b/drivers/w1/w1_therm.c 2005-03-04 12:37:51 -08:00
@@ -104,6 +104,7 @@
int i, max_trying = 10;
atomic_inc(sl-refcnt);
+ smp_mb__after_atomic_inc();
if (down_interruptible(sl-master-mutex)) {
count = 0;
goto out_dec;
@@ -179,6 +180,7 @@
out:
up(dev-mutex);
out_dec:
+ smp_mb__before_atomic_inc();
atomic_dec(sl-refcnt);
return count;
-
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the body of a message to [EMAIL PROTECTED]
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Please read the FAQ at http://www.tux.org/lkml/
