tracing/filter: Remove synchronize_sched() from __alloc_preds()

Because the filters are processed first and then activated
(added to the call), we no longer need to worry about the preds
of the filter in __alloc_preds() being used. As the filter that
is allocating preds is not activated yet.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 7 insertions, 23 deletions

diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index f5d335d28d0b..3249b4f77ef0 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -795,33 +795,17 @@ static int __alloc_preds(struct event_filter *filter, int n_preds)
         struct filter_pred *pred;
         int i;
 
-        if (filter->preds) {
-                if (filter->a_preds < n_preds) {
-                        /*
-                         * We need to reallocate.
-                         * We should have already have zeroed out
-                         * the pred count and called synchronized_sched()
-                         * to make sure no one is using the preds.
-                         */
-                        if (WARN_ON_ONCE(filter->n_preds)) {
-                                /* We need to reset it now */
-                                filter->n_preds = 0;
-                                synchronize_sched();
-                        }
-                        __free_preds(filter);
-                }
-        }
+        if (filter->preds)
+                __free_preds(filter);
+
+        filter->preds =
+                kzalloc(sizeof(*filter->preds) * n_preds, GFP_KERNEL);
 
-        if (!filter->preds) {
-                filter->preds =
-                        kzalloc(sizeof(*filter->preds) * n_preds, GFP_KERNEL);
-                filter->a_preds = n_preds;
-        }
         if (!filter->preds)
                 return -ENOMEM;
 
-        if (WARN_ON(filter->a_preds < n_preds))
-                return -EINVAL;
+        filter->a_preds = n_preds;
+        filter->n_preds = 0;
 
         for (i = 0; i < n_preds; i++) {
                 pred = &filter->preds[i];