This CL adds a trigger and a service so that Systrace can be used
for tracing events during boot.
persist.debug.atrace.boottrace property is used for switching on
and off tracing during boot. /data/misc/boottrace/categories
file is used for specifying the categories to be traced.
These property and file are rewritten by Systrace when the newly
added option --boot is specified.
Here is an example of tracing events of am and wm catetories
during boot.
$ external/chromium-trace/systrace am wm --boot
This command will cause the device to reboot. Once the device has
booted up, the trace report is created by hitting Ctrl+C.
As written in readme.txt, this mechanism relies on persistent
property, so tracing events that are emitted before that are not
recorded. This is enough for tracing events after zygote is
launched though.
This only works on userdebug or eng build for security reason.
BUG: 21739901
Change-Id: I03f2963d77a678f47eab5e3e29fc7e91bc9ca3a4
The systrace permissions from init.trace.rc and the "class_start core"
which launches surfaceflinger are both in an "on boot" section. However,
the init.trace.rc commands are parsed after all commands in init.rc.
This means that "class_start core" is executed before the chmod command
which allows processes to write to trace_marker. If any services
execute their first trace command before the chmod occurs, then that
service won't be able to write traces until the service is restarted.
To fix this, run all of the init.trace.rc commands in the "early-boot"
section to ensure they are completed first.
Bug: 17612265
Change-Id: Ibf544762173d5ba98272c66ef485d8eab7d70bf3
Need the set correct permission for print-tgid option or tracing of
sched can't work on user build.
Change-Id: Ia88aabe58128b911afd78f01c27f7da884ed03f0
Signed-off-by: Carton He <carton.he@marvell.com>
This change adds init.rc steps to:
* allow kernel tracing to be enabled via adb
* allow a limited set of kernel trace events to be enabled via adb
* allow the kernel trace to be read via adb
* allow all users to write to the kernel trace from userland
Bug: 6513400
Change-Id: Ic3c189b5697aa5edf88d2f507c932971bed6caff
Scott Bauer