Idlestat: Plug memory leaks from inter() and topology

Function inter() may return newly allocated structures or one of the
parameters (if the other parameter is NULL). This function is called
in a loop from cluster_data(), core_cluster_data() and
physical_cluster_data() with one of the parameters often being an
earlier return value from inter(). This causes a great number of
structure allocations without matching memory releases.

Code in topology.c takes the result from *_cluster_data(), but it
only releases the top-level structure, without releasing the
data pointed to by top-level structure members.

This patch plugs both types of leaks. Since the memory pointed to
by inter() may or may not be allocated by that call, a new member
has been added to struct cpuidle_cstate to indicate the origin
of the structure.

This patch also adds detection for data aliasing related to inter(),
but does not remove the bug.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@linaro.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/idlestat.h b/idlestat.h
index a32aab9..253d2b9 100644
--- a/idlestat.h
+++ b/idlestat.h
@@ -63,6 +63,7 @@ struct cpuidle_cstate {
 	double min_time;
 	double duration;
 	int target_residency; /* -1 if not available */
+	int inter_result; /* 1 if created by a call to inter() */
 };
 
 struct wakeup_irq {
@@ -87,6 +88,8 @@ struct cpuidle_cstates {
 	enum {as_expected, too_long, too_short} actual_residency;
 };
 
+extern void release_cstate_info(struct cpuidle_cstates *cstates, int nrcpus);
+
 struct cpufreq_pstate {
 	int id;
 	unsigned int freq;