bus: arm-ccn: Fix error handling at event allocation

The bitfield allocation function returns error condition
as a negative value, but in two cases its result
was assigned to an unsigned member of the hw_perf_event
structure, thus the error would not be ever detected.

Fixed by using an intermediate, signed variable.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
This commit is contained in:
Pawel Moll 2014-07-31 16:16:37 +01:00 committed by Olof Johansson
parent f64a3c895b
commit 3e528cb7ba
1 changed files with 5 additions and 4 deletions

View File

@ -591,7 +591,7 @@ static int arm_ccn_pmu_event_init(struct perf_event *event)
struct arm_ccn *ccn;
struct hw_perf_event *hw = &event->hw;
u32 node_xp, type, event_id;
int valid;
int valid, bit;
struct arm_ccn_component *source;
int i;
@ -713,17 +713,18 @@ static int arm_ccn_pmu_event_init(struct perf_event *event)
/* Allocate an event source or a watchpoint */
if (type == CCN_TYPE_XP && event_id == CCN_EVENT_WATCHPOINT)
hw->config_base = arm_ccn_pmu_alloc_bit(source->xp.dt_cmp_mask,
bit = arm_ccn_pmu_alloc_bit(source->xp.dt_cmp_mask,
CCN_NUM_XP_WATCHPOINTS);
else
hw->config_base = arm_ccn_pmu_alloc_bit(source->pmu_events_mask,
bit = arm_ccn_pmu_alloc_bit(source->pmu_events_mask,
CCN_NUM_PMU_EVENTS);
if (hw->config_base < 0) {
if (bit < 0) {
dev_warn(ccn->dev, "No more event sources/watchpoints on node/XP %d!\n",
node_xp);
clear_bit(hw->idx, ccn->dt.pmu_counters_mask);
return -EAGAIN;
}
hw->config_base = bit;
ccn->dt.pmu_counters[hw->idx].event = event;