platform_system_core/logd
Tom Cherry 4f22786cc9 logd: rework logic for LogTimeEntry
LogTimeEntry's lifecycle is spread out in various locations.  It
further seems incomplete as there is logic that assumes that its
associated thread can exit while the underlying LogTimeEntry remains
valid, however it doesn't appear that that is actually a supported
situation.

This change simplifies this logic to have only one valid state for a
LogTimeEntry: it must have its thread running and be present in
LastLogTimes.  A LogTimeEntry will never be placed into LastLogTimes
unless its thread is running and its thread will remove its associated
LogTimeEntry from LastLogTimes before it has exited.

This admittedly breaks situations where a blocking socket gets issued
multiple commands with different pid filters, tail lines, etc,
however, I'm reasonably sure that these situations were already
broken.  A check is added to close the socket in this case.

Test: multiple logcat instances work, logd.reader.per's are cleaned up
Change-Id: Ibe8651e7d530c5e9a8d6ce3150cd247982887cbe
2018-10-12 18:28:59 -07:00
..
tests LogAudit: remove dynamic rate limiter 2018-01-03 12:52:58 -08:00
.clang-format logd: specify clang format 2017-03-13 10:31:09 -07:00
Android.bp bpfmt. 2018-02-16 17:58:14 -08:00
Android.mk logd + liblogd to Android.bp 2017-06-29 09:29:36 -07:00
CommandListener.cpp [logd] Modernize codebase by replacing NULL with nullptr 2018-07-13 17:50:55 -07:00
CommandListener.h logd: specify clang format 2017-03-13 10:31:09 -07:00
FlushCommand.cpp logd: rework logic for LogTimeEntry 2018-10-12 18:28:59 -07:00
FlushCommand.h logd: rework logic for LogTimeEntry 2018-10-12 18:28:59 -07:00
LogAudit.cpp Replace (unsigned) short with (u)int16_t. 2018-08-13 14:24:33 -07:00
LogAudit.h Logd: include app package name in selinux metadata 2018-05-03 22:40:18 -07:00
LogBuffer.cpp logd: rework logic for LogTimeEntry 2018-10-12 18:28:59 -07:00
LogBuffer.h Replace (unsigned) short with (u)int16_t. 2018-08-13 14:24:33 -07:00
LogBufferElement.cpp Replace (unsigned) short with (u)int16_t. 2018-08-13 14:24:33 -07:00
LogBufferElement.h Replace (unsigned) short with (u)int16_t. 2018-08-13 14:24:33 -07:00
LogBufferInterface.cpp logd: validate and fill in socket credentials 2017-05-11 12:21:02 -07:00
LogBufferInterface.h Replace (unsigned) short with (u)int16_t. 2018-08-13 14:24:33 -07:00
LogCommand.cpp [logd] Modernize codebase by replacing NULL with nullptr 2018-07-13 17:50:55 -07:00
LogCommand.h logd: specify clang format 2017-03-13 10:31:09 -07:00
LogKlog.cpp Suppress implicit-fallthrough warnings. 2018-09-17 16:50:11 +00:00
LogKlog.h logd: ASAN cleansing 2017-03-27 13:32:57 -07:00
LogListener.cpp Replace (unsigned) short with (u)int16_t. 2018-08-13 14:24:33 -07:00
LogListener.h logd: validate and fill in socket credentials 2017-05-11 12:21:02 -07:00
LogReader.cpp logd: rework logic for LogTimeEntry 2018-10-12 18:28:59 -07:00
LogReader.h Remove execute bit for source files 2018-07-13 17:45:39 -07:00
LogStatistics.cpp Replace (unsigned) short with (u)int16_t. 2018-08-13 14:24:33 -07:00
LogStatistics.h Add noexcept to move constructors and assignment operators. 2018-10-05 16:43:47 +00:00
LogTags.cpp [logd] Modernize codebase by replacing NULL with nullptr 2018-07-13 17:50:55 -07:00
LogTags.h [logd] Modernize codebase by replacing NULL with nullptr 2018-07-13 17:50:55 -07:00
LogTimes.cpp logd: rework logic for LogTimeEntry 2018-10-12 18:28:59 -07:00
LogTimes.h logd: rework logic for LogTimeEntry 2018-10-12 18:28:59 -07:00
LogUtils.h logd: validate and fill in socket credentials 2017-05-11 12:21:02 -07:00
LogWhiteBlackList.cpp [logd] Modernize codebase by replacing NULL with nullptr 2018-07-13 17:50:55 -07:00
LogWhiteBlackList.h logd: specify clang format 2017-03-13 10:31:09 -07:00
OWNERS Add OWNERS. 2017-12-07 13:30:03 -08:00
README.auditd logd: selinux auditd initial commit 2014-04-07 10:51:00 -07:00
README.property Use ro.logd.kernel for kernel logcat 2018-01-02 10:47:50 -08:00
event.logtags liblog: logprint supports number of seconds time event field 2017-04-14 12:54:25 -07:00
libaudit.c LogAudit: remove dynamic rate limiter 2018-01-03 12:52:58 -08:00
libaudit.h LogAudit: remove dynamic rate limiter 2018-01-03 12:52:58 -08:00
logd.rc logd: Move the capabilities from file based to ambient 2018-06-11 10:04:11 -07:00
logtagd.rc logd: add getEventTag command and service 2017-02-02 14:24:18 -08:00
main.cpp logd: crash dumps on userdebug only 2018-08-22 20:09:34 +00:00

README.property

The properties that logd and friends react to are:

name                       type default  description
ro.logd.auditd             bool   true   Enable selinux audit daemon
ro.logd.auditd.dmesg       bool   true   selinux audit messages sent to dmesg.
ro.logd.auditd.main        bool   true   selinux audit messages sent to main.
ro.logd.auditd.events      bool   true   selinux audit messages sent to events.
persist.logd.security      bool   false  Enable security buffer.
ro.device_owner            bool   false  Override persist.logd.security to false
ro.logd.kernel             bool+ svelte+ Enable klogd daemon
ro.logd.statistics         bool+ svelte+ Enable logcat -S statistics.
ro.debuggable              number        if not "1", logd.statistics &
                                         ro.logd.kernel default false.
logd.logpersistd.enable    bool   auto   Safe to start logpersist daemon service
logd.logpersistd          string persist Enable logpersist daemon, "logcatd"
                                         turns on logcat -f in logd context.
					 Responds to logcatd, clear and stop.
logd.logpersistd.buffer          persist logpersistd buffers to collect
logd.logpersistd.size            persist logpersistd size in MB
persist.logd.logpersistd   string        Enable logpersist daemon, "logcatd"
                                         turns on logcat -f in logd context.
persist.logd.logpersistd.buffer    all   logpersistd buffers to collect
persist.logd.logpersistd.size      256   logpersistd size in MB
persist.logd.size          number  ro    Global default size of the buffer for
                                         all log ids at initial startup, at
                                         runtime use: logcat -b all -G <value>
ro.logd.size               number svelte default for persist.logd.size. Larger
                                         platform default sizes than 256KB are
                                         known to not scale well under log spam
                                         pressure. Address the spam first,
                                         resist increasing the log buffer.
persist.logd.size.<buffer> number  ro    Size of the buffer for <buffer> log
ro.logd.size.<buffer>      number svelte default for persist.logd.size.<buffer>
ro.config.low_ram          bool   false  if true, logd.statistics,
                                         ro.logd.kernel default false,
                                         logd.size 64K instead of 256K.
persist.logd.filter        string        Pruning filter to optimize content.
                                         At runtime use: logcat -P "<string>"
ro.logd.filter       string "~! ~1000/!" default for persist.logd.filter.
                                         This default means to prune the
                                         oldest entries of chattiest UID, and
                                         the chattiest PID of system
                                         (1000, or AID_SYSTEM).
persist.logd.timestamp     string  ro    The recording timestamp source.
                                         "m[onotonic]" is the only supported
                                         key character, otherwise realtime.
ro.logd.timestamp        string realtime default for persist.logd.timestamp
log.tag                   string persist The global logging level, VERBOSE,
                                         DEBUG, INFO, WARN, ERROR, ASSERT or
                                         SILENT. Only the first character is
                                         the key character.
persist.log.tag            string build  default for log.tag
log.tag.<tag>             string persist The <tag> specific logging level.
persist.log.tag.<tag>      string build  default for log.tag.<tag>

NB:
- auto - managed by /init
- bool+ - "true", "false" and comma separated list of "eng" (forced false if
  ro.debuggable is not "1") or "svelte" (forced false if ro.config.low_ram is
  true).
- svelte - see ro.config.low_ram for details.
- svelte+ - see ro.config.low_ram and ro.debuggable for details.
- ro - <base property> temporary override, ro.<base property> platform default.
- persist - <base property> override, persist.<base property> platform default.
- build - VERBOSE for native, DEBUG for jvm isLoggable, or developer option.
- number - support multipliers (K or M) for convenience. Range is limited
  to between 64K and 256M for log buffer sizes. Individual log buffer ids
  such as main, system, ... override global default.
- Pruning filter is of form of a space-separated list of [~][UID][/PID]
  references, where '~' prefix means to blacklist otherwise whitelist. For
  blacklisting, UID or PID may be a '!' to instead reference the chattiest
  client, with the restriction that the PID must be in the UID group 1000
  (system or AID_SYSTEM).