logd: optimize statistics

- Go back to basic requirements
- Simplify
- use hash tables to minimize memory impact

Bug: 19608965
Change-Id: If7becb34354d6415e5c387ecea7d4109a15259c8
diff --git a/logd/LogStatistics.h b/logd/LogStatistics.h
index f892cd0..d5b8762 100644
--- a/logd/LogStatistics.h
+++ b/logd/LogStatistics.h
@@ -20,175 +20,60 @@
 #include <sys/types.h>
 
 #include <log/log.h>
-#include <log/log_read.h>
-#include <utils/List.h>
+#include <utils/BasicHashtable.h>
+
+#include "LogBufferElement.h"
 
 #define log_id_for_each(i) \
     for (log_id_t i = LOG_ID_MIN; i < LOG_ID_MAX; i = (log_id_t) (i + 1))
 
-class PidStatistics {
-    const pid_t pid;
-
-    // Total
-    size_t mSizesTotal;
-    size_t mElementsTotal;
-    // Current
-    size_t mSizes;
-    size_t mElements;
-
-    char *name;
-    bool mGone;
-
-public:
-    static const pid_t gone = (pid_t) -1;
-
-    PidStatistics(pid_t pid, char *name = NULL);
-    PidStatistics(const PidStatistics &copy);
-    ~PidStatistics();
-
-    pid_t getPid() const { return pid; }
-    bool pidGone();
-    char *getName() const { return name; }
-    void setName(char *name);
-
-    void add(unsigned short size);
-    bool subtract(unsigned short size); // returns true if stats and PID gone
-    void addTotal(size_t size, size_t element);
-
-    size_t sizes() const { return mSizes; }
-    size_t elements() const { return mElements; }
-
-    size_t sizesTotal() const { return mSizesTotal; }
-    size_t elementsTotal() const { return mElementsTotal; }
-
-    // helper
-    static char *pidToName(pid_t pid);
-};
-
-typedef android::List<PidStatistics *> PidStatisticsCollection;
-
-class UidStatistics {
+struct UidEntry {
     const uid_t uid;
+    size_t size;
 
-    PidStatisticsCollection Pids;
+    UidEntry(uid_t uid):uid(uid),size(0) { }
 
-    void insert(PidStatisticsCollection::iterator i, PidStatistics *p)
-        { Pids.insert(i, p); }
-    void push_back(PidStatistics *p) { Pids.push_back(p); }
-
-    size_t mSizes;
-    size_t mElements;
-
-public:
-    UidStatistics(uid_t uid);
-    ~UidStatistics();
-
-    PidStatisticsCollection::iterator begin() { return Pids.begin(); }
-    PidStatisticsCollection::iterator end() { return Pids.end(); }
-    PidStatisticsCollection::iterator erase(PidStatisticsCollection::iterator i)
-        { return Pids.erase(i); }
-
-    uid_t getUid() { return uid; }
-
-    void add(unsigned short size, pid_t pid);
-    void subtract(unsigned short size, pid_t pid);
-    void sort();
-
-    static const pid_t pid_all = (pid_t) -1;
-
-    // fast track current value
-    size_t sizes() const { return mSizes; };
-    size_t elements() const { return mElements; };
-
-    // statistical track
-    size_t sizes(pid_t pid);
-    size_t elements(pid_t pid);
-
-    size_t sizesTotal(pid_t pid = pid_all);
-    size_t elementsTotal(pid_t pid = pid_all);
-
-    // helper
-    static char *pidToName(pid_t pid) { return PidStatistics::pidToName(pid); }
-};
-
-typedef android::List<UidStatistics *> UidStatisticsCollection;
-
-class LidStatistics {
-    UidStatisticsCollection Uids;
-
-public:
-    LidStatistics();
-    ~LidStatistics();
-
-    UidStatisticsCollection::iterator begin() { return Uids.begin(); }
-    UidStatisticsCollection::iterator end() { return Uids.end(); }
-
-    void add(unsigned short size, uid_t uid, pid_t pid);
-    void subtract(unsigned short size, uid_t uid, pid_t pid);
-    void sort();
-
-    static const pid_t pid_all = (pid_t) -1;
-    static const uid_t uid_all = (uid_t) -1;
-
-    size_t sizes(uid_t uid = uid_all, pid_t pid = pid_all);
-    size_t elements(uid_t uid = uid_all, pid_t pid = pid_all);
-
-    size_t sizesTotal(uid_t uid = uid_all, pid_t pid = pid_all);
-    size_t elementsTotal(uid_t uid = uid_all, pid_t pid = pid_all);
+    inline const uid_t&getKey() const { return uid; }
+    size_t getSizes() const { return size; }
+    inline void add(size_t s) { size += s; }
+    inline bool subtract(size_t s) { size -= s; return !size; }
 };
 
 // Log Statistics
 class LogStatistics {
-    LidStatistics LogIds[LOG_ID_MAX];
-
     size_t mSizes[LOG_ID_MAX];
     size_t mElements[LOG_ID_MAX];
+    size_t mSizesTotal[LOG_ID_MAX];
+    size_t mElementsTotal[LOG_ID_MAX];
 
-    bool mStatistics;
-
-    static const unsigned short mBuckets[14];
-    log_time mMinimum[sizeof(mBuckets) / sizeof(mBuckets[0])];
+    // uid to size list
+    typedef android::BasicHashtable<uid_t, UidEntry> uidTable_t;
+    uidTable_t uidTable[LOG_ID_MAX];
 
 public:
-    const log_time start;
-
     LogStatistics();
 
-    LidStatistics &id(log_id_t log_id) { return LogIds[log_id]; }
+    void enableStatistics() { }
 
-    void enableStatistics() { mStatistics = true; }
+    void add(LogBufferElement *entry);
+    void subtract(LogBufferElement *entry);
 
-    void add(unsigned short size, log_id_t log_id, uid_t uid, pid_t pid);
-    void subtract(unsigned short size, log_id_t log_id, uid_t uid, pid_t pid);
-    void sort();
+    // Caller must delete array
+    const UidEntry **sort(size_t n, log_id i);
 
     // fast track current value by id only
     size_t sizes(log_id_t id) const { return mSizes[id]; }
     size_t elements(log_id_t id) const { return mElements[id]; }
-
-    // statistical track
-    static const log_id_t log_id_all = (log_id_t) -1;
-    static const uid_t uid_all = (uid_t) -1;
-    static const pid_t pid_all = (pid_t) -1;
-
-    size_t sizes(log_id_t id, uid_t uid, pid_t pid = pid_all);
-    size_t elements(log_id_t id, uid_t uid, pid_t pid = pid_all);
-    size_t sizes() { return sizes(log_id_all, uid_all); }
-    size_t elements() { return elements(log_id_all, uid_all); }
-
-    size_t sizesTotal(log_id_t id = log_id_all,
-                      uid_t uid = uid_all,
-                      pid_t pid = pid_all);
-    size_t elementsTotal(log_id_t id = log_id_all,
-                         uid_t uid = uid_all,
-                         pid_t pid = pid_all);
+    size_t sizesTotal(log_id_t id) const { return mSizesTotal[id]; }
+    size_t elementsTotal(log_id_t id) const { return mElementsTotal[id]; }
 
     // *strp = malloc, balance with free
-    void format(char **strp, uid_t uid, unsigned int logMask, log_time oldest);
+    void format(char **strp, uid_t uid, unsigned int logMask);
 
     // helper
-    static char *pidToName(pid_t pid) { return PidStatistics::pidToName(pid); }
+    char *pidToName(pid_t pid);
     uid_t pidToUid(pid_t pid);
+    char *uidToName(uid_t uid);
 };
 
 #endif // _LOGD_LOG_STATISTICS_H__