logd: remove LogFindWorst
LogStatistics relies on LogBuffer's lock for thread safety, but that
will be cleaned up in future CLs. It won't be possible to return a
'LogFindWorst' object that references internal LogStatistics pointers
in a thread safe way, so we remove this and provide a more simple
interface.
This also removes unnecessary allocations; std::array of 2 or 32
entries is small enough to allocate on the stack.
Test: logging unit tests
Change-Id: I38bfcba5b08c640ffd3af5c078bc716688f6edf8
diff --git a/logd/LogBuffer.cpp b/logd/LogBuffer.cpp
index 2cb0c5e..ad391e5 100644
--- a/logd/LogBuffer.cpp
+++ b/logd/LogBuffer.cpp
@@ -663,19 +663,14 @@
// Calculate threshold as 12.5% of available storage
size_t threshold = log_buffer_size(id) / 8;
- if ((id == LOG_ID_EVENTS) || (id == LOG_ID_SECURITY)) {
- stats.sortTags(AID_ROOT, (pid_t)0, 2, id)
- .findWorst(worst, worst_sizes, second_worst_sizes,
- threshold);
+ if (id == LOG_ID_EVENTS || id == LOG_ID_SECURITY) {
+ stats.WorstTwoTags(threshold, &worst, &worst_sizes, &second_worst_sizes);
// per-pid filter for AID_SYSTEM sources is too complex
} else {
- stats.sort(AID_ROOT, (pid_t)0, 2, id)
- .findWorst(worst, worst_sizes, second_worst_sizes,
- threshold);
+ stats.WorstTwoUids(id, threshold, &worst, &worst_sizes, &second_worst_sizes);
- if ((worst == AID_SYSTEM) && prune_->worstPidOfSystemEnabled()) {
- stats.sortPids(worst, (pid_t)0, 2, id)
- .findWorst(worstPid, worst_sizes, second_worst_sizes);
+ if (worst == AID_SYSTEM && prune_->worstPidOfSystemEnabled()) {
+ stats.WorstTwoSystemPids(id, worst_sizes, &worstPid, &second_worst_sizes);
}
}
}
diff --git a/logd/LogStatistics.cpp b/logd/LogStatistics.cpp
index 431b778..4c4c1db 100644
--- a/logd/LogStatistics.cpp
+++ b/logd/LogStatistics.cpp
@@ -297,6 +297,49 @@
return name;
}
+template <typename TKey, typename TEntry>
+void LogStatistics::WorstTwoWithThreshold(const LogHashtable<TKey, TEntry>& table, size_t threshold,
+ int* worst, size_t* worst_sizes,
+ size_t* second_worst_sizes) {
+ std::array<const TEntry*, 2> max_entries;
+ table.MaxEntries(AID_ROOT, 0, &max_entries);
+ if (max_entries[0] == nullptr || max_entries[1] == nullptr) {
+ return;
+ }
+ *worst_sizes = max_entries[0]->getSizes();
+ // b/24782000: Allow time horizon to extend roughly tenfold, assume average entry length is
+ // 100 characters.
+ if (*worst_sizes > threshold && *worst_sizes > (10 * max_entries[0]->getDropped())) {
+ *worst = max_entries[0]->getKey();
+ *second_worst_sizes = max_entries[1]->getSizes();
+ if (*second_worst_sizes < threshold) {
+ *second_worst_sizes = threshold;
+ }
+ }
+}
+
+void LogStatistics::WorstTwoUids(log_id id, size_t threshold, int* worst, size_t* worst_sizes,
+ size_t* second_worst_sizes) {
+ WorstTwoWithThreshold(uidTable[id], threshold, worst, worst_sizes, second_worst_sizes);
+}
+
+void LogStatistics::WorstTwoTags(size_t threshold, int* worst, size_t* worst_sizes,
+ size_t* second_worst_sizes) {
+ WorstTwoWithThreshold(tagTable, threshold, worst, worst_sizes, second_worst_sizes);
+}
+
+void LogStatistics::WorstTwoSystemPids(log_id id, size_t worst_uid_sizes, int* worst,
+ size_t* second_worst_sizes) {
+ std::array<const PidEntry*, 2> max_entries;
+ pidSystemTable[id].MaxEntries(AID_SYSTEM, 0, &max_entries);
+ if (max_entries[0] == nullptr || max_entries[1] == nullptr) {
+ return;
+ }
+
+ *worst = max_entries[0]->getKey();
+ *second_worst_sizes = worst_uid_sizes - max_entries[0]->getSizes() + max_entries[1]->getSizes();
+}
+
std::string UidEntry::formatHeader(const std::string& name, log_id_t id) const {
bool isprune = worstUidEnabledForLogid(id);
return formatLine(android::base::StringPrintf(name.c_str(),
@@ -401,12 +444,9 @@
}
static const size_t maximum_sorted_entries = 32;
- std::unique_ptr<const PidEntry* []> sorted =
- stat.pidSystemTable[id].sort(uid, (pid_t)0, maximum_sorted_entries);
+ std::array<const PidEntry*, maximum_sorted_entries> sorted;
+ stat.pidSystemTable[id].MaxEntries(uid, 0, &sorted);
- if (!sorted.get()) {
- return output;
- }
std::string byPid;
size_t index;
bool hasDropped = false;
diff --git a/logd/LogStatistics.h b/logd/LogStatistics.h
index 0782de3..ed9002a 100644
--- a/logd/LogStatistics.h
+++ b/logd/LogStatistics.h
@@ -14,8 +14,7 @@
* limitations under the License.
*/
-#ifndef _LOGD_LOG_STATISTICS_H__
-#define _LOGD_LOG_STATISTICS_H__
+#pragma once
#include <ctype.h>
#include <inttypes.h>
@@ -25,6 +24,7 @@
#include <sys/types.h>
#include <algorithm> // std::max
+#include <array>
#include <memory>
#include <string>
#include <string_view>
@@ -79,16 +79,12 @@
typedef
typename std::unordered_map<TKey, TEntry>::const_iterator const_iterator;
- std::unique_ptr<const TEntry* []> sort(uid_t uid, pid_t pid,
- size_t len) const {
- if (!len) {
- std::unique_ptr<const TEntry* []> sorted(nullptr);
- return sorted;
- }
-
- const TEntry** retval = new const TEntry*[len];
- memset(retval, 0, sizeof(*retval) * len);
-
+ // Returns a sorted array of up to len highest entries sorted by size. If fewer than len
+ // entries are found, their positions are set to nullptr.
+ template <size_t len>
+ void MaxEntries(uid_t uid, pid_t pid, std::array<const TEntry*, len>* out) const {
+ auto& retval = *out;
+ retval.fill(nullptr);
for (const_iterator it = map.begin(); it != map.end(); ++it) {
const TEntry& entry = it->second;
@@ -113,8 +109,6 @@
retval[index] = &entry;
}
}
- std::unique_ptr<const TEntry* []> sorted(retval);
- return sorted;
}
inline iterator add(const TKey& key, const LogBufferElement* element) {
@@ -176,11 +170,8 @@
log_id_t id = LOG_ID_MAX) const {
static const size_t maximum_sorted_entries = 32;
std::string output;
- std::unique_ptr<const TEntry* []> sorted =
- sort(uid, pid, maximum_sorted_entries);
- if (!sorted.get()) {
- return output;
- }
+ std::array<const TEntry*, maximum_sorted_entries> sorted;
+ MaxEntries(uid, pid, &sorted);
bool headerPrinted = false;
for (size_t index = 0; index < maximum_sorted_entries; ++index) {
const TEntry* entry = sorted[index];
@@ -627,41 +618,6 @@
std::string format(const LogStatistics& stat, log_id_t id) const;
};
-template <typename TEntry>
-class LogFindWorst {
- std::unique_ptr<const TEntry* []> sorted;
-
- public:
- explicit LogFindWorst(std::unique_ptr<const TEntry* []>&& sorted)
- : sorted(std::move(sorted)) {
- }
-
- void findWorst(int& worst, size_t& worst_sizes, size_t& second_worst_sizes,
- size_t threshold) {
- if (sorted.get() && sorted[0] && sorted[1]) {
- worst_sizes = sorted[0]->getSizes();
- if ((worst_sizes > threshold)
- // Allow time horizon to extend roughly tenfold, assume
- // average entry length is 100 characters.
- && (worst_sizes > (10 * sorted[0]->getDropped()))) {
- worst = sorted[0]->getKey();
- second_worst_sizes = sorted[1]->getSizes();
- if (second_worst_sizes < threshold) {
- second_worst_sizes = threshold;
- }
- }
- }
- }
-
- void findWorst(int& worst, size_t worst_sizes, size_t& second_worst_sizes) {
- if (sorted.get() && sorted[0] && sorted[1]) {
- worst = sorted[0]->getKey();
- second_worst_sizes =
- worst_sizes - sorted[0]->getSizes() + sorted[1]->getSizes();
- }
- }
-};
-
// Log Statistics
class LogStatistics {
friend UidEntry;
@@ -748,16 +704,12 @@
--mDroppedElements[log_id];
}
- LogFindWorst<UidEntry> sort(uid_t uid, pid_t pid, size_t len, log_id id) {
- return LogFindWorst<UidEntry>(uidTable[id].sort(uid, pid, len));
- }
- LogFindWorst<PidEntry> sortPids(uid_t uid, pid_t pid, size_t len,
- log_id id) {
- return LogFindWorst<PidEntry>(pidSystemTable[id].sort(uid, pid, len));
- }
- LogFindWorst<TagEntry> sortTags(uid_t uid, pid_t pid, size_t len, log_id) {
- return LogFindWorst<TagEntry>(tagTable.sort(uid, pid, len));
- }
+ void WorstTwoUids(log_id id, size_t threshold, int* worst, size_t* worst_sizes,
+ size_t* second_worst_sizes);
+ void WorstTwoTags(size_t threshold, int* worst, size_t* worst_sizes,
+ size_t* second_worst_sizes);
+ void WorstTwoSystemPids(log_id id, size_t worst_uid_sizes, int* worst,
+ size_t* second_worst_sizes);
// fast track current value by id only
size_t sizes(log_id_t id) const {
@@ -785,6 +737,9 @@
const char* pidToName(pid_t pid) const;
uid_t pidToUid(pid_t pid);
const char* uidToName(uid_t uid) const;
-};
-#endif // _LOGD_LOG_STATISTICS_H__
+ private:
+ template <typename TKey, typename TEntry>
+ void WorstTwoWithThreshold(const LogHashtable<TKey, TEntry>& table, size_t threshold,
+ int* worst, size_t* worst_sizes, size_t* second_worst_sizes);
+};