39cc3e7073
Allow for a daemon to write to last kmsg to propagate a detailed
subreason to kernel_panic,sysrq actions. A minor refactor moves
common code into a helper function getSubreason for retrieval and
bit error correction operations.
A sysrq crash generally produces a kernel-provided message:
SysRq : Trigger a crash
which is used to generate a canonical boot reason kernel_panic,sysrq.
A user daemon could write to /dev/kmsg just prior to the sysrq with
SysRq : Trigger a crash : '<subreason>'
to change the canonical boot reason to kernel_panic,sysrq,<subreason>.
Administration added pending kBootReasonMap entries present in TRON.
Test: manual echo into /dev/kmsg and /proc/sysrq-trigger and check
Test: boot_reason_test.sh
Bug: 33808187
Bug: 63736262
Change-Id: Ibf5432737e5a3449ebe40a8c6cf2d3e912ed6bbc
|
||
|---|---|---|
| .. | ||
| .clang-format | ||
| Android.bp | ||
| AndroidTest.xml | ||
| OWNERS | ||
| README.md | ||
| boot_event_record_store.cpp | ||
| boot_event_record_store.h | ||
| boot_event_record_store_test.cpp | ||
| boot_reason_test.sh | ||
| bootstat-debug.rc | ||
| bootstat.cpp | ||
| bootstat.rc | ||
| testrunner.cpp | ||
README.md
bootstat
The bootstat command records boot events (e.g., firmware_loaded,
boot_complete) and the relative time at which these events occurred. The
command also aggregates boot event metrics locally and logs the metrics for
analysis.
Usage: bootstat [options]
options include:
-h, --help Show this help
-l, --log Log all metrics to logstorage
-p, --print Dump the boot event records to the console
-r, --record Record the timestamp of a named boot event
--record_boot_reason Record the reason why the device booted
--record_time_since_factory_reset Record the time since the device was reset
Relative time
The timestamp recorded by bootstat is the uptime of the system, i.e., the number of seconds since the system booted.
Recording boot events
To record the relative time of an event during the boot phase, call bootstat
with the -r option and the name of the boot event.
$ bootstat -r boot_complete
The relative time at which the command runs is recorded along with the name of the boot event to be persisted.
Logging boot events
To log the persisted boot events, call bootstat with the -l option.
$ bootstat -l
bootstat logs all boot events recorded using the -r option to the EventLog
using the Tron histogram. These logs may be uploaded by interested parties
for aggregation and analysis of boot time across different devices and
versions.
Printing boot events
To print the set of persisted boot events, call bootstat with the -p option.
$ bootstat -p
Boot events:
------------
boot_complete 71