Commit Graph

8 Commits

Author SHA1 Message Date
Mark Salyzyn c9e5f37166 liblog: add android_lookupEventTagNum
android_lookupEventTagNum added.  Adds support for creating a new
log tag at runtime, registered to the logd service.

Tested on Hikey, all services stopped, shell only access, CPUs not
locked (there is enough repeatability on this platform).

$ /data/nativetest64/liblog-benchmarks/liblog-benchmarks BM_lookupEventTagNum

                          iterations      ns/op
Precharge: start
Precharge: stop 231
NB: only Tag matching, linear lookup (as reference, before unordered_map)
BM_lookupEventTagNum         1000000       1017
NB: unordered_map with full Tag & Format lookup, but with Tag hashing
BM_lookupEventTagNum         2000000        683
NB: with full Tag & Format hash and lookup for matching
BM_lookupEventTagNum         2000000        814
NB: only Tag matching (Hail Mary path)
BM_lookupEventTagNum         5000000        471

Because the database can now be dynamic, we added reader/writer locks
which adds a 65ns (uncontended) premium on lookups, and switch to
check for an allocation adds 25ns (either open code, or using
string_view, no difference) which means our overall speed takes 90%
as long as the requests did before we switched to unordered_map.
Faster than before where we originally utilized binary lookup on
static content, but not by much.  Dynamic updates that are not cached
locally take the following times to acquire long path to logd to
generate.

BM_lookupEventTag           20000000         139
BM_lookupEventTag_NOT       20000000         87
BM_lookupEventFormat        20000000         139
BM_lookupEventTagNum_logd_new   5000         335936
BM_lookupEventTagNum_logd_existing 10000     249226

The long path pickups are mitigated by the built-in caching, and
the public mapping in /dev/event-log-tags.

SideEffects: Event tags and signal handlers do not mix
Test: liblog benchmarks
Bug: 31456426
Change-Id: I69e6489d899cf35cdccffcee0d8d7cad469ada0a
2017-02-02 15:21:15 -08:00
Mark Salyzyn cfd5b080af system/core: preparation to pull back interfaces from android/log.h
Point to log/log.h where necessary, define LOG_TAG where necessary.
Accept that private/android_logger.h is suitable replacement for
log/logger.h and android/log.h.

Correct liblog/README

Effectively a cleanup and controlled select revert of
'system/core: drop or replace log/logger.h' and
'system/core: Replace log/log.h with android/log.h'.

Test: compile
Bug: 30465923
Change-Id: Ic2ad157bad6f5efe2c6af293a73bb753300b17a2
2016-10-20 08:11:39 -07:00
Mark Salyzyn db8a266aea liblog: __android_log_pmsg_file_write() cleanup
__android_log_pmsg_file_write() will open /dev/pmsg0 if not
already, and will close it if we opened it.

Added atomic access to the android_log_context as insurance.

Fortify and correct pmsg tests.

Test: gTest liblog-unit-tests --gtest_filter=liblog.__android_log_pmsg_file_*
Bug: 31958686
Change-Id: I2cf6f971b6968938f471fda67367efe20dae3004
2016-10-13 21:43:42 +00:00
Mark Salyzyn 6584d0a35a liblog: Replace log/log.h with android/log.h
Move all liblog related content into android/log.h, and make
log/log.h points to android/log.h.

Test: Compile
Bug: 26552300
Bug: 31289077
Change-Id: I858e0ebe047b86f2a8530a99bc9c380d3d58edbb
2016-09-30 12:47:05 -07:00
Mark Salyzyn a166708d15 liblog: logcat: Replace log/logd.h with log/log.h
Should use log/log.h and in some cases android/log.h instead. Can
not remove file because still in use by partners, so log/logd.h
points to log/log.h.

Test: Compile
Bug: 26552300
Bug: 31289077
Change-Id: I3580d46154617abb7231027a44f4ab9ee023febf
2016-09-30 12:47:05 -07:00
Mark Salyzyn 004cd3c55d liblog: logd: logcat: deprecate log/log_read.h
Always used in combination with log/logger.h except in log_time.cpp,
and not used externally.  As a result liblog has to support stl, a
small price to pay since goal is to convert liblog to C++ internally.

Test: compile
Bug: 31456426
Bug: 26552300
Bug: 31289077
Change-Id: I72828ec807d0a2c8e40bbdebd7a69f147a7ca5a9
2016-09-30 12:47:05 -07:00
Mark Salyzyn ccfb244b36 liblog: logcat -g readable size wrong
Bug: 28451229
Change-Id: I4bbc2bed933d69416c23cc7af617be3fb55d0b62
2016-04-29 07:39:51 -07:00
Mark Salyzyn 018a96d03f liblog: split out transports into separate files
Create config_logger, logger and logger_read to house the log
interfaces. Add fake_logger, logd_logger and pmsg_logger to
house the write and read transports. Allows for an easier and
direct path to add new transports to the library.

SideEffects: None, logger benchmark performance unaffected

Bug: 27176738
Bug: 27405083
Change-Id: I01b38637334a5242905c8c89f6ab0a92e2540008
2016-03-22 13:01:15 -07:00