LogStatistics.h revision c723df805a1a3199577cac947cebf2ab53abdb34 
1/*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef _LOGD_LOG_STATISTICS_H__
18#define _LOGD_LOG_STATISTICS_H__
19
20#include <memory>
21#include <stdlib.h>
22#include <sys/types.h>
23
24#include <algorithm> // std::max
25#include <string>    // std::string
26#include <unordered_map>
27
28#include <base/stringprintf.h>
29#include <log/log.h>
30#include <private/android_filesystem_config.h>
31
32#include "LogBufferElement.h"
33#include "LogUtils.h"
34
35#define log_id_for_each(i) \
36    for (log_id_t i = LOG_ID_MIN; i < LOG_ID_MAX; i = (log_id_t) (i + 1))
37
38class LogStatistics;
39
40template <typename TKey, typename TEntry>
41class LogHashtable {
42
43    std::unordered_map<TKey, TEntry> map;
44
45public:
46
47    typedef typename std::unordered_map<TKey, TEntry>::iterator iterator;
48    typedef typename std::unordered_map<TKey, TEntry>::const_iterator const_iterator;
49
50    std::unique_ptr<const TEntry *[]> sort(size_t len) const {
51        if (!len) {
52            std::unique_ptr<const TEntry *[]> sorted(NULL);
53            return sorted;
54        }
55
56        const TEntry **retval = new const TEntry* [len];
57        memset(retval, 0, sizeof(*retval) * len);
58
59        for(const_iterator it = map.begin(); it != map.end(); ++it) {
60            const TEntry &entry = it->second;
61            size_t sizes = entry.getSizes();
62            ssize_t index = len - 1;
63            while ((!retval[index] || (sizes > retval[index]->getSizes()))
64                    && (--index >= 0))
65                ;
66            if (++index < (ssize_t)len) {
67                size_t num = len - index - 1;
68                if (num) {
69                    memmove(&retval[index + 1], &retval[index],
70                            num * sizeof(retval[0]));
71                }
72                retval[index] = &entry;
73            }
74        }
75        std::unique_ptr<const TEntry *[]> sorted(retval);
76        return sorted;
77    }
78
79    inline iterator add(TKey key, LogBufferElement *element) {
80        iterator it = map.find(key);
81        if (it == map.end()) {
82            it = map.insert(std::make_pair(key, TEntry(element))).first;
83        } else {
84            it->second.add(element);
85        }
86        return it;
87    }
88
89    inline iterator add(TKey key) {
90        iterator it = map.find(key);
91        if (it == map.end()) {
92            it = map.insert(std::make_pair(key, TEntry(key))).first;
93        } else {
94            it->second.add(key);
95        }
96        return it;
97    }
98
99    void subtract(TKey key, LogBufferElement *element) {
100        iterator it = map.find(key);
101        if ((it != map.end()) && it->second.subtract(element)) {
102            map.erase(it);
103        }
104    }
105
106    inline void drop(TKey key, LogBufferElement *element) {
107        iterator it = map.find(key);
108        if (it != map.end()) {
109            it->second.drop(element);
110        }
111    }
112
113    inline iterator begin() { return map.begin(); }
114    inline const_iterator begin() const { return map.begin(); }
115    inline iterator end() { return map.end(); }
116    inline const_iterator end() const { return map.end(); }
117
118    std::string format(
119            const LogStatistics &stat,
120            uid_t uid,
121            const std::string &name = std::string(""),
122            log_id_t id = LOG_ID_MAX) const {
123        static const size_t maximum_sorted_entries = 32;
124        std::string output;
125        std::unique_ptr<const TEntry *[]> sorted = sort(maximum_sorted_entries);
126
127        if (!sorted.get()) {
128            return output;
129        }
130        bool headerPrinted = false;
131        for (size_t index = 0; index < maximum_sorted_entries; ++index) {
132            const TEntry *entry = sorted[index];
133            if (!entry) {
134                break;
135            }
136            if (entry->getSizes() <= (sorted[0]->getSizes() / 100)) {
137                break;
138            }
139            if ((uid != AID_ROOT) && (uid != entry->getUid())) {
140                continue;
141            }
142            if (!headerPrinted) {
143                output += "\n\n";
144                output += entry->formatHeader(name, id);
145                headerPrinted = true;
146            }
147            output += entry->format(stat, id);
148        }
149        return output;
150    }
151};
152
153namespace EntryBaseConstants {
154    static constexpr size_t pruned_len = 14;
155    static constexpr size_t total_len = 80;
156}
157
158struct EntryBase {
159    size_t size;
160
161    EntryBase():size(0) { }
162    EntryBase(LogBufferElement *element):size(element->getMsgLen()) { }
163
164    size_t getSizes() const { return size; }
165
166    inline void add(LogBufferElement *element) { size += element->getMsgLen(); }
167    inline bool subtract(LogBufferElement *element) {
168        size -= element->getMsgLen();
169        return !size;
170    }
171
172    static std::string formatLine(
173            const std::string &name,
174            const std::string &size,
175            const std::string &pruned) {
176        ssize_t drop_len = std::max(pruned.length() + 1,
177                                    EntryBaseConstants::pruned_len);
178        ssize_t size_len = std::max(size.length() + 1,
179                                    EntryBaseConstants::total_len
180                                        - name.length() - drop_len - 1);
181
182        if (pruned.length()) {
183            return android::base::StringPrintf("%s%*s%*s\n", name.c_str(),
184                                               (int)size_len, size.c_str(),
185                                               (int)drop_len, pruned.c_str());
186        } else {
187            return android::base::StringPrintf("%s%*s\n", name.c_str(),
188                                               (int)size_len, size.c_str());
189        }
190    }
191};
192
193struct EntryBaseDropped : public EntryBase {
194    size_t dropped;
195
196    EntryBaseDropped():dropped(0) { }
197    EntryBaseDropped(LogBufferElement *element):
198            EntryBase(element),
199            dropped(element->getDropped()){
200    }
201
202    size_t getDropped() const { return dropped; }
203
204    inline void add(LogBufferElement *element) {
205        dropped += element->getDropped();
206        EntryBase::add(element);
207    }
208    inline bool subtract(LogBufferElement *element) {
209        dropped -= element->getDropped();
210        return EntryBase::subtract(element) && !dropped;
211    }
212    inline void drop(LogBufferElement *element) {
213        dropped += 1;
214        EntryBase::subtract(element);
215    }
216};
217
218struct UidEntry : public EntryBaseDropped {
219    const uid_t uid;
220
221    UidEntry(LogBufferElement *element):
222            EntryBaseDropped(element),
223            uid(element->getUid()) {
224    }
225
226    inline const uid_t&getKey() const { return uid; }
227    inline const uid_t&getUid() const { return uid; }
228
229    std::string formatHeader(const std::string &name, log_id_t id) const;
230    std::string format(const LogStatistics &stat, log_id_t id) const;
231};
232
233namespace android {
234uid_t pidToUid(pid_t pid);
235}
236
237struct PidEntry : public EntryBaseDropped {
238    const pid_t pid;
239    uid_t uid;
240    char *name;
241
242    PidEntry(pid_t pid):
243            EntryBaseDropped(),
244            pid(pid),
245            uid(android::pidToUid(pid)),
246            name(android::pidToName(pid)) {
247    }
248    PidEntry(LogBufferElement *element):
249            EntryBaseDropped(element),
250            pid(element->getPid()),
251            uid(element->getUid()),
252            name(android::pidToName(pid)) {
253    }
254    PidEntry(const PidEntry &element):
255            EntryBaseDropped(element),
256            pid(element.pid),
257            uid(element.uid),
258            name(element.name ? strdup(element.name) : NULL) {
259    }
260    ~PidEntry() { free(name); }
261
262    const pid_t&getKey() const { return pid; }
263    const uid_t&getUid() const { return uid; }
264    const char*getName() const { return name; }
265
266    inline void add(pid_t newPid) {
267        if (name && !fast<strncmp>(name, "zygote", 6)) {
268            free(name);
269            name = NULL;
270        }
271        if (!name) {
272            name = android::pidToName(newPid);
273        }
274    }
275
276    inline void add(LogBufferElement *element) {
277        uid_t incomingUid = element->getUid();
278        if (getUid() != incomingUid) {
279            uid = incomingUid;
280            free(name);
281            name = android::pidToName(element->getPid());
282        } else {
283            add(element->getPid());
284        }
285        EntryBaseDropped::add(element);
286    }
287
288    std::string formatHeader(const std::string &name, log_id_t id) const;
289    std::string format(const LogStatistics &stat, log_id_t id) const;
290};
291
292struct TidEntry : public EntryBaseDropped {
293    const pid_t tid;
294    uid_t uid;
295    char *name;
296
297    TidEntry(pid_t tid):
298            EntryBaseDropped(),
299            tid(tid),
300            uid(android::pidToUid(tid)),
301            name(android::tidToName(tid)) {
302    }
303    TidEntry(LogBufferElement *element):
304            EntryBaseDropped(element),
305            tid(element->getTid()),
306            uid(element->getUid()),
307            name(android::tidToName(tid)) {
308    }
309    TidEntry(const TidEntry &element):
310            EntryBaseDropped(element),
311            tid(element.tid),
312            uid(element.uid),
313            name(element.name ? strdup(element.name) : NULL) {
314    }
315    ~TidEntry() { free(name); }
316
317    const pid_t&getKey() const { return tid; }
318    const uid_t&getUid() const { return uid; }
319    const char*getName() const { return name; }
320
321    inline void add(pid_t incomingTid) {
322        if (name && !fast<strncmp>(name, "zygote", 6)) {
323            free(name);
324            name = NULL;
325        }
326        if (!name) {
327            name = android::tidToName(incomingTid);
328        }
329    }
330
331    inline void add(LogBufferElement *element) {
332        uid_t incomingUid = element->getUid();
333        if (getUid() != incomingUid) {
334            uid = incomingUid;
335            free(name);
336            name = android::tidToName(element->getTid());
337        } else {
338            add(element->getTid());
339        }
340        EntryBaseDropped::add(element);
341    }
342
343    std::string formatHeader(const std::string &name, log_id_t id) const;
344    std::string format(const LogStatistics &stat, log_id_t id) const;
345};
346
347struct TagEntry : public EntryBase {
348    const uint32_t tag;
349    uid_t uid;
350
351    TagEntry(LogBufferElement *element):
352            EntryBase(element),
353            tag(element->getTag()),
354            uid(element->getUid()) {
355    }
356
357    const uint32_t&getKey() const { return tag; }
358    const uid_t&getUid() const { return uid; }
359    const char*getName() const { return android::tagToName(tag); }
360
361    inline void add(LogBufferElement *element) {
362        uid_t incomingUid = element->getUid();
363        if (uid != incomingUid) {
364            uid = -1;
365        }
366        EntryBase::add(element);
367    }
368
369    std::string formatHeader(const std::string &name, log_id_t id) const;
370    std::string format(const LogStatistics &stat, log_id_t id) const;
371};
372
373// Log Statistics
374class LogStatistics {
375    friend UidEntry;
376
377    size_t mSizes[LOG_ID_MAX];
378    size_t mElements[LOG_ID_MAX];
379    size_t mDroppedElements[LOG_ID_MAX];
380    size_t mSizesTotal[LOG_ID_MAX];
381    size_t mElementsTotal[LOG_ID_MAX];
382    bool enable;
383
384    // uid to size list
385    typedef LogHashtable<uid_t, UidEntry> uidTable_t;
386    uidTable_t uidTable[LOG_ID_MAX];
387
388    // pid to uid list
389    typedef LogHashtable<pid_t, PidEntry> pidTable_t;
390    pidTable_t pidTable;
391
392    // tid to uid list
393    typedef LogHashtable<pid_t, TidEntry> tidTable_t;
394    tidTable_t tidTable;
395
396    // tag list
397    typedef LogHashtable<uint32_t, TagEntry> tagTable_t;
398    tagTable_t tagTable;
399
400public:
401    LogStatistics();
402
403    void enableStatistics() { enable = true; }
404
405    void add(LogBufferElement *entry);
406    void subtract(LogBufferElement *entry);
407    // entry->setDropped(1) must follow this call
408    void drop(LogBufferElement *entry);
409    // Correct for coalescing two entries referencing dropped content
410    void erase(LogBufferElement *element) {
411        log_id_t log_id = element->getLogId();
412        --mElements[log_id];
413        --mDroppedElements[log_id];
414    }
415
416    std::unique_ptr<const UidEntry *[]> sort(size_t len, log_id id) {
417        return uidTable[id].sort(len);
418    }
419
420    // fast track current value by id only
421    size_t sizes(log_id_t id) const { return mSizes[id]; }
422    size_t elements(log_id_t id) const { return mElements[id]; }
423    size_t realElements(log_id_t id) const {
424        return mElements[id] - mDroppedElements[id];
425    }
426    size_t sizesTotal(log_id_t id) const { return mSizesTotal[id]; }
427    size_t elementsTotal(log_id_t id) const { return mElementsTotal[id]; }
428
429    std::string format(uid_t uid, unsigned int logMask) const;
430
431    // helper (must be locked directly or implicitly by mLogElementsLock)
432    const char *pidToName(pid_t pid) const;
433    uid_t pidToUid(pid_t pid);
434    const char *uidToName(uid_t uid) const;
435};
436
437#endif // _LOGD_LOG_STATISTICS_H__
438