anierin/msm-5.15
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

UPSTREAM: perf/arm-cmn: Move group validation data off-stack

Browse Source 
With the value of CMN_MAX_DTMS increasing significantly, our validation
data structure is set to get quite big. Technically we could pack it at
least twice as densely, since we only need around 19 bits of information
per DTM, but that makes the code even more mind-bogglingly impenetrable,
and even half of "quite big" may still be uncomfortably large for a
stack frame (~1KB). Just move it to an off-stack allocation instead.

Bug: 247832918
Change-Id: Ic8dbd216bb85e2db53c91cfba85c670cc030e1f7
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/0cabff2e5839ddc0979e757c55515966f65359e4.1638530442.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
(cherry picked from commit 558a07807038017255005a4820f600da643d8a5f)
Signed-off-by: Robin Peng <robinpeng@google.com>
This commit is contained in:
Robin Murphy
2021-12-03 11:44:58 +00:00
committed by Treehugger Robot
parent 9a74f34abd
commit b6a7974310
1 changed files with 25 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

43
drivers/perf/arm-cmn.c
View File

@@ -876,8 +876,8 @@ static int arm_cmn_validate_group(struct perf_event *event)
struct arm_cmn_node *dn;
struct perf_event *sibling, *leader = event->group_leader;
enum cmn_node_type type;
struct arm_cmn_val val;
int i;
struct arm_cmn_val *val;
int i, ret = -EINVAL;
u8 occupid;
if (leader == event)
@@ -886,18 +886,22 @@ static int arm_cmn_validate_group(struct perf_event *event)
if (event->pmu != leader->pmu && !is_software_event(leader))
return -EINVAL;
memset(&val, 0, sizeof(val));
val = kzalloc(sizeof(*val), GFP_KERNEL);
if (!val)
return -ENOMEM;
arm_cmn_val_add_event(&val, leader);
arm_cmn_val_add_event(val, leader);
for_each_sibling_event(sibling, leader)
arm_cmn_val_add_event(&val, sibling);
arm_cmn_val_add_event(val, sibling);
type = CMN_EVENT_TYPE(event);
if (type == CMN_TYPE_DTC)
return val.cycles ? -EINVAL : 0;
if (type == CMN_TYPE_DTC) {
ret = val->cycles ? -EINVAL : 0;
goto done;
}
if (val.dtc_count == CMN_DT_NUM_COUNTERS)
return -EINVAL;
if (val->dtc_count == CMN_DT_NUM_COUNTERS)
goto done;
if (arm_cmn_is_occup_event(type, CMN_EVENT_EVENTID(event)))
occupid = CMN_EVENT_OCCUPID(event) + 1;
@@ -907,25 +911,28 @@ static int arm_cmn_validate_group(struct perf_event *event)
for_each_hw_dn(hw, dn, i) {
int wp_idx, wp_cmb, dtm = dn->dtm;
if (val.dtm_count[dtm] == CMN_DTM_NUM_COUNTERS)
return -EINVAL;
if (val->dtm_count[dtm] == CMN_DTM_NUM_COUNTERS)
goto done;
if (occupid && val.occupid[dtm] && occupid != val.occupid[dtm])
return -EINVAL;
if (occupid && val->occupid[dtm] && occupid != val->occupid[dtm])
goto done;
if (type != CMN_TYPE_WP)
continue;
wp_idx = arm_cmn_wp_idx(event);
if (val.wp[dtm][wp_idx])
return -EINVAL;
if (val->wp[dtm][wp_idx])
goto done;
wp_cmb = val.wp[dtm][wp_idx ^ 1];
wp_cmb = val->wp[dtm][wp_idx ^ 1];
if (wp_cmb && wp_cmb != CMN_EVENT_WP_COMBINE(event) + 1)
return -EINVAL;
goto done;
}
return 0;
ret = 0;
done:
kfree(val);
return ret;
}
static int arm_cmn_event_init(struct perf_event *event)