android_system_core/logd/LogStatistics.cpp
Jeff Sharkey dff44709cf Define range of GIDs for cached app data.
To support upcoming disk usage calculation optimizations, this change
creates a new GID for each app that will be used to mark its cached
data.  We're allocating these unique GIDs so that we can use
quotactl() to track cached data on a per-app basis.

This change also tightens up the implementation of both the cache
and shared GID calculation to ensure that they stay inside the valid
ranges, and includes tests to verify.

Test: builds, boots, tests pass
Bug: 27948817
Change-Id: Ie4377e5aae267f2da39a165888139228995987cb
2016-12-13 13:28:08 -07:00

630 lines
20 KiB
C++

/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <fcntl.h>
#include <pwd.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <list>
#include <android/log.h>
#include "LogStatistics.h"
LogStatistics::LogStatistics() : enable(false) {
log_id_for_each(id) {
mSizes[id] = 0;
mElements[id] = 0;
mDroppedElements[id] = 0;
mSizesTotal[id] = 0;
mElementsTotal[id] = 0;
}
}
namespace android {
// caller must own and free character string
char *pidToName(pid_t pid) {
char *retval = NULL;
if (pid == 0) { // special case from auditd/klogd for kernel
retval = strdup("logd");
} else {
char buffer[512];
snprintf(buffer, sizeof(buffer), "/proc/%u/cmdline", pid);
int fd = open(buffer, O_RDONLY);
if (fd >= 0) {
ssize_t ret = read(fd, buffer, sizeof(buffer));
if (ret > 0) {
buffer[sizeof(buffer)-1] = '\0';
// frameworks intermediate state
if (fastcmp<strcmp>(buffer, "<pre-initialized>")) {
retval = strdup(buffer);
}
}
close(fd);
}
}
return retval;
}
}
void LogStatistics::add(LogBufferElement *element) {
log_id_t log_id = element->getLogId();
unsigned short size = element->getMsgLen();
mSizes[log_id] += size;
++mElements[log_id];
mSizesTotal[log_id] += size;
++mElementsTotal[log_id];
if (log_id == LOG_ID_KERNEL) {
return;
}
uidTable[log_id].add(element->getUid(), element);
if (element->getUid() == AID_SYSTEM) {
pidSystemTable[log_id].add(element->getPid(), element);
}
if (!enable) {
return;
}
pidTable.add(element->getPid(), element);
tidTable.add(element->getTid(), element);
uint32_t tag = element->getTag();
if (tag) {
if (log_id == LOG_ID_SECURITY) {
securityTagTable.add(tag, element);
} else {
tagTable.add(tag, element);
}
}
}
void LogStatistics::subtract(LogBufferElement *element) {
log_id_t log_id = element->getLogId();
unsigned short size = element->getMsgLen();
mSizes[log_id] -= size;
--mElements[log_id];
if (element->getDropped()) {
--mDroppedElements[log_id];
}
if (log_id == LOG_ID_KERNEL) {
return;
}
uidTable[log_id].subtract(element->getUid(), element);
if (element->getUid() == AID_SYSTEM) {
pidSystemTable[log_id].subtract(element->getPid(), element);
}
if (!enable) {
return;
}
pidTable.subtract(element->getPid(), element);
tidTable.subtract(element->getTid(), element);
uint32_t tag = element->getTag();
if (tag) {
if (log_id == LOG_ID_SECURITY) {
securityTagTable.subtract(tag, element);
} else {
tagTable.subtract(tag, element);
}
}
}
// Atomically set an entry to drop
// entry->setDropped(1) must follow this call, caller should do this explicitly.
void LogStatistics::drop(LogBufferElement *element) {
log_id_t log_id = element->getLogId();
unsigned short size = element->getMsgLen();
mSizes[log_id] -= size;
++mDroppedElements[log_id];
uidTable[log_id].drop(element->getUid(), element);
if (element->getUid() == AID_SYSTEM) {
pidSystemTable[log_id].drop(element->getPid(), element);
}
if (!enable) {
return;
}
pidTable.drop(element->getPid(), element);
tidTable.drop(element->getTid(), element);
uint32_t tag = element->getTag();
if (tag) {
if (log_id == LOG_ID_SECURITY) {
securityTagTable.drop(tag, element);
} else {
tagTable.drop(tag, element);
}
}
}
// caller must own and free character string
const char *LogStatistics::uidToName(uid_t uid) const {
// Local hard coded favourites
if (uid == AID_LOGD) {
return strdup("auditd");
}
// Android system
if (uid < AID_APP) {
// in bionic, thread safe as long as we copy the results
struct passwd *pwd = getpwuid(uid);
if (pwd) {
return strdup(pwd->pw_name);
}
}
// Parse /data/system/packages.list
uid_t userId = uid % AID_USER_OFFSET;
const char *name = android::uidToName(userId);
if (!name && (userId > (AID_SHARED_GID_START - AID_APP))) {
name = android::uidToName(userId - (AID_SHARED_GID_START - AID_APP));
}
if (name) {
return name;
}
// Android application
if (uid >= AID_APP) {
struct passwd *pwd = getpwuid(uid);
if (pwd) {
return strdup(pwd->pw_name);
}
}
// report uid -> pid(s) -> pidToName if unique
for(pidTable_t::const_iterator it = pidTable.begin(); it != pidTable.end(); ++it) {
const PidEntry &entry = it->second;
if (entry.getUid() == uid) {
const char *nameTmp = entry.getName();
if (nameTmp) {
if (!name) {
name = strdup(nameTmp);
} else if (fastcmp<strcmp>(name, nameTmp)) {
free(const_cast<char *>(name));
name = NULL;
break;
}
}
}
}
// No one
return name;
}
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(), android_log_id_to_name(id)),
std::string("Size"),
std::string(isprune ? "+/- Pruned" : ""))
+ formatLine(std::string("UID PACKAGE"),
std::string("BYTES"),
std::string(isprune ? "NUM" : ""));
}
std::string UidEntry::format(const LogStatistics &stat, log_id_t id) const {
uid_t uid = getUid();
std::string name = android::base::StringPrintf("%u", uid);
const char *nameTmp = stat.uidToName(uid);
if (nameTmp) {
name += android::base::StringPrintf(
"%*s%s", (int)std::max(6 - name.length(), (size_t)1),
"", nameTmp);
free(const_cast<char *>(nameTmp));
}
std::string size = android::base::StringPrintf("%zu", getSizes());
std::string pruned = "";
if (worstUidEnabledForLogid(id)) {
size_t totalDropped = 0;
for (LogStatistics::uidTable_t::const_iterator it = stat.uidTable[id].begin();
it != stat.uidTable[id].end(); ++it) {
totalDropped += it->second.getDropped();
}
size_t sizes = stat.sizes(id);
size_t totalSize = stat.sizesTotal(id);
size_t totalElements = stat.elementsTotal(id);
float totalVirtualSize = (float)sizes + (float)totalDropped * totalSize
/ totalElements;
size_t entrySize = getSizes();
float virtualEntrySize = entrySize;
int realPermille = virtualEntrySize * 1000.0 / sizes;
size_t dropped = getDropped();
if (dropped) {
pruned = android::base::StringPrintf("%zu", dropped);
virtualEntrySize += (float)dropped * totalSize / totalElements;
}
int virtualPermille = virtualEntrySize * 1000.0 / totalVirtualSize;
int permille = (realPermille - virtualPermille) * 1000L
/ (virtualPermille ?: 1);
if ((permille < -1) || (1 < permille)) {
std::string change;
const char *units = "%";
const char *prefix = (permille > 0) ? "+" : "";
if (permille > 999) {
permille = (permille + 1000) / 100; // Now tenths fold
units = "X";
prefix = "";
}
if ((-99 < permille) && (permille < 99)) {
change = android::base::StringPrintf("%s%d.%u%s",
prefix,
permille / 10,
((permille < 0) ? (-permille % 10) : (permille % 10)),
units);
} else {
change = android::base::StringPrintf("%s%d%s",
prefix,
(permille + 5) / 10, units);
}
ssize_t spaces = EntryBaseConstants::pruned_len
- 2 - pruned.length() - change.length();
if ((spaces <= 0) && pruned.length()) {
spaces = 1;
}
if ((spaces > 0) && (pruned.length() != 0)) {
change += android::base::StringPrintf("%*s", (int)spaces, "");
}
pruned = change + pruned;
}
}
std::string output = formatLine(name, size, pruned);
if (uid != AID_SYSTEM) {
return output;
}
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);
if (!sorted.get()) {
return output;
}
std::string byPid;
size_t index;
bool hasDropped = false;
for (index = 0; index < maximum_sorted_entries; ++index) {
const PidEntry *entry = sorted[index];
if (!entry) {
break;
}
if (entry->getSizes() <= (getSizes() / 100)) {
break;
}
if (entry->getDropped()) {
hasDropped = true;
}
byPid += entry->format(stat, id);
}
if (index > 1) { // print this only if interesting
std::string ditto("\" ");
output += formatLine(std::string(" PID/UID COMMAND LINE"),
ditto, hasDropped ? ditto : std::string(""));
output += byPid;
}
return output;
}
std::string PidEntry::formatHeader(const std::string &name, log_id_t /* id */) const {
return formatLine(name,
std::string("Size"),
std::string("Pruned"))
+ formatLine(std::string(" PID/UID COMMAND LINE"),
std::string("BYTES"),
std::string("NUM"));
}
std::string PidEntry::format(const LogStatistics &stat, log_id_t /* id */) const {
uid_t uid = getUid();
pid_t pid = getPid();
std::string name = android::base::StringPrintf("%5u/%u", pid, uid);
const char *nameTmp = getName();
if (nameTmp) {
name += android::base::StringPrintf(
"%*s%s", (int)std::max(12 - name.length(), (size_t)1),
"", nameTmp);
} else if ((nameTmp = stat.uidToName(uid))) {
name += android::base::StringPrintf(
"%*s%s", (int)std::max(12 - name.length(), (size_t)1),
"", nameTmp);
free(const_cast<char *>(nameTmp));
}
std::string size = android::base::StringPrintf("%zu",
getSizes());
std::string pruned = "";
size_t dropped = getDropped();
if (dropped) {
pruned = android::base::StringPrintf("%zu", dropped);
}
return formatLine(name, size, pruned);
}
std::string TidEntry::formatHeader(const std::string &name, log_id_t /* id */) const {
return formatLine(name,
std::string("Size"),
std::string("Pruned"))
+ formatLine(std::string(" TID/UID COMM"),
std::string("BYTES"),
std::string("NUM"));
}
std::string TidEntry::format(const LogStatistics &stat, log_id_t /* id */) const {
uid_t uid = getUid();
std::string name = android::base::StringPrintf("%5u/%u",
getTid(), uid);
const char *nameTmp = getName();
if (nameTmp) {
name += android::base::StringPrintf(
"%*s%s", (int)std::max(12 - name.length(), (size_t)1),
"", nameTmp);
} else if ((nameTmp = stat.uidToName(uid))) {
// if we do not have a PID name, lets punt to try UID name?
name += android::base::StringPrintf(
"%*s%s", (int)std::max(12 - name.length(), (size_t)1),
"", nameTmp);
free(const_cast<char *>(nameTmp));
// We tried, better to not have a name at all, we still
// have TID/UID by number to report in any case.
}
std::string size = android::base::StringPrintf("%zu",
getSizes());
std::string pruned = "";
size_t dropped = getDropped();
if (dropped) {
pruned = android::base::StringPrintf("%zu", dropped);
}
return formatLine(name, size, pruned);
}
std::string TagEntry::formatHeader(const std::string &name, log_id_t id) const {
bool isprune = worstUidEnabledForLogid(id);
return formatLine(name,
std::string("Size"),
std::string(isprune ? "Prune" : ""))
+ formatLine(std::string(" TAG/UID TAGNAME"),
std::string("BYTES"),
std::string(isprune ? "NUM" : ""));
}
std::string TagEntry::format(const LogStatistics & /* stat */, log_id_t /* id */) const {
std::string name;
uid_t uid = getUid();
if (uid == (uid_t)-1) {
name = android::base::StringPrintf("%7u",
getKey());
} else {
name = android::base::StringPrintf("%7u/%u",
getKey(), uid);
}
size_t len = 0;
const char *nameTmp = getName(len);
if (nameTmp) {
name += android::base::StringPrintf(
"%*s%.*s", (int)std::max(14 - name.length(), (size_t)1),
"", (int)len, nameTmp);
}
std::string size = android::base::StringPrintf("%zu",
getSizes());
std::string pruned = "";
size_t dropped = getDropped();
if (dropped) {
pruned = android::base::StringPrintf("%zu", dropped);
}
return formatLine(name, size, pruned);
}
std::string LogStatistics::format(uid_t uid, pid_t pid,
unsigned int logMask) const {
static const unsigned short spaces_total = 19;
// Report on total logging, current and for all time
std::string output = "size/num";
size_t oldLength;
short spaces = 1;
log_id_for_each(id) {
if (!(logMask & (1 << id))) continue;
oldLength = output.length();
if (spaces < 0) spaces = 0;
output += android::base::StringPrintf("%*s%s", spaces, "",
android_log_id_to_name(id));
spaces += spaces_total + oldLength - output.length();
}
if (spaces < 0) spaces = 0;
output += android::base::StringPrintf("%*sTotal", spaces, "");
static const char TotalStr[] = "\nTotal";
spaces = 10 - strlen(TotalStr);
output += TotalStr;
size_t totalSize = 0;
size_t totalEls = 0;
log_id_for_each(id) {
if (!(logMask & (1 << id))) continue;
oldLength = output.length();
if (spaces < 0) spaces = 0;
size_t szs = sizesTotal(id);
totalSize += szs;
size_t els = elementsTotal(id);
totalEls += els;
output += android::base::StringPrintf("%*s%zu/%zu", spaces, "", szs, els);
spaces += spaces_total + oldLength - output.length();
}
if (spaces < 0) spaces = 0;
output += android::base::StringPrintf("%*s%zu/%zu", spaces, "", totalSize, totalEls);
static const char NowStr[] = "\nNow";
spaces = 10 - strlen(NowStr);
output += NowStr;
totalSize = 0;
totalEls = 0;
log_id_for_each(id) {
if (!(logMask & (1 << id))) continue;
size_t els = elements(id);
if (els) {
oldLength = output.length();
if (spaces < 0) spaces = 0;
size_t szs = sizes(id);
totalSize += szs;
totalEls += els;
output += android::base::StringPrintf("%*s%zu/%zu", spaces, "", szs, els);
spaces -= output.length() - oldLength;
}
spaces += spaces_total;
}
if (spaces < 0) spaces = 0;
output += android::base::StringPrintf("%*s%zu/%zu", spaces, "", totalSize, totalEls);
static const char OverheadStr[] = "\nOverhead";
spaces = 10 - strlen(OverheadStr);
output += OverheadStr;
totalSize = 0;
log_id_for_each(id) {
if (!(logMask & (1 << id))) continue;
size_t els = elements(id);
if (els) {
oldLength = output.length();
if (spaces < 0) spaces = 0;
// estimate the std::list overhead.
static const size_t overhead =
((sizeof(LogBufferElement) + sizeof(uint64_t) - 1) &
-sizeof(uint64_t)) +
sizeof(std::list<LogBufferElement*>);
size_t szs = sizes(id) + els * overhead;
totalSize += szs;
output += android::base::StringPrintf("%*s%zu", spaces, "", szs);
spaces -= output.length() - oldLength;
}
spaces += spaces_total;
}
totalSize += sizeOf();
if (spaces < 0) spaces = 0;
output += android::base::StringPrintf("%*s%zu", spaces, "", totalSize);
// Report on Chattiest
std::string name;
// Chattiest by application (UID)
log_id_for_each(id) {
if (!(logMask & (1 << id))) continue;
name = (uid == AID_ROOT)
? "Chattiest UIDs in %s log buffer:"
: "Logging for your UID in %s log buffer:";
output += uidTable[id].format(*this, uid, pid, name, id);
}
if (enable) {
name = ((uid == AID_ROOT) && !pid)
? "Chattiest PIDs:"
: "Logging for this PID:";
output += pidTable.format(*this, uid, pid, name);
name = "Chattiest TIDs";
if (pid) name += android::base::StringPrintf(" for PID %d", pid);
name += ":";
output += tidTable.format(*this, uid, pid, name);
}
if (enable && (logMask & (1 << LOG_ID_EVENTS))) {
name = "Chattiest events log buffer TAGs";
if (pid) name += android::base::StringPrintf(" for PID %d", pid);
name += ":";
output += tagTable.format(*this, uid, pid, name, LOG_ID_EVENTS);
}
if (enable && (logMask & (1 << LOG_ID_SECURITY))) {
name = "Chattiest security log buffer TAGs";
if (pid) name += android::base::StringPrintf(" for PID %d", pid);
name += ":";
output += securityTagTable.format(*this, uid, pid, name, LOG_ID_SECURITY);
}
return output;
}
namespace android {
uid_t pidToUid(pid_t pid) {
char buffer[512];
snprintf(buffer, sizeof(buffer), "/proc/%u/status", pid);
FILE *fp = fopen(buffer, "r");
if (fp) {
while (fgets(buffer, sizeof(buffer), fp)) {
int uid;
if (sscanf(buffer, "Uid: %d", &uid) == 1) {
fclose(fp);
return uid;
}
}
fclose(fp);
}
return AID_LOGD; // associate this with the logger
}
}
uid_t LogStatistics::pidToUid(pid_t pid) {
return pidTable.add(pid)->second.getUid();
}
// caller must free character string
const char *LogStatistics::pidToName(pid_t pid) const {
// An inconvenient truth ... getName() can alter the object
pidTable_t &writablePidTable = const_cast<pidTable_t &>(pidTable);
const char *name = writablePidTable.add(pid)->second.getName();
if (!name) {
return NULL;
}
return strdup(name);
}