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markers: remove ACCESS_ONCE 

As Paul pointed out, the ACCESS_ONCE are not needed because we already have
the explicit surrounding memory barriers.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Mike Mason <mmlnx@us.ibm.com>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Cc: David Smith <dsmith@redhat.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Adrian Bunk <adrian.bunk@movial.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mathieu Desnoyers 2008-03-24 12:29:49 -07:00 committed by Linus Torvalds
parent fd3c36f8b5
commit 58336114af
1 changed files with 6 additions and 6 deletions
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12
kernel/marker.c
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@ -109,13 +109,13 @@ void marker_probe_cb(const struct marker *mdata, void *call_private,
* modules and they insure RCU read coherency.
*/
preempt_disable();
ptype = ACCESS_ONCE(mdata->ptype);
ptype = mdata->ptype;
if (likely(!ptype)) {
marker_probe_func *func;
/* Must read the ptype before ptr. They are not data dependant,
* so we put an explicit smp_rmb() here. */
smp_rmb();
func = ACCESS_ONCE(mdata->single.func);
func = mdata->single.func;
/* Must read the ptr before private data. They are not data
* dependant, so we put an explicit smp_rmb() here. */
smp_rmb();
@ -133,7 +133,7 @@ void marker_probe_cb(const struct marker *mdata, void *call_private,
* in the fast path, so put the explicit barrier here.
*/
smp_read_barrier_depends();
multi = ACCESS_ONCE(mdata->multi);
multi = mdata->multi;
for (i = 0; multi[i].func; i++) {
va_start(args, fmt);
multi[i].func(multi[i].probe_private, call_private, fmt,
@ -161,13 +161,13 @@ void marker_probe_cb_noarg(const struct marker *mdata,
char ptype;
preempt_disable();
ptype = ACCESS_ONCE(mdata->ptype);
ptype = mdata->ptype;
if (likely(!ptype)) {
marker_probe_func *func;
/* Must read the ptype before ptr. They are not data dependant,
* so we put an explicit smp_rmb() here. */
smp_rmb();
func = ACCESS_ONCE(mdata->single.func);
func = mdata->single.func;
/* Must read the ptr before private data. They are not data
* dependant, so we put an explicit smp_rmb() here. */
smp_rmb();
@ -183,7 +183,7 @@ void marker_probe_cb_noarg(const struct marker *mdata,
* in the fast path, so put the explicit barrier here.
*/
smp_read_barrier_depends();
multi = ACCESS_ONCE(mdata->multi);
multi = mdata->multi;
for (i = 0; multi[i].func; i++)
multi[i].func(multi[i].probe_private, call_private, fmt,
&args);