sascha/devlib
1
0
Fork 0
mirror of https://github.com/ARM-software/devlib.git synced 2025-01-31 10:10:46 +00:00
Code Issues Releases Wiki Activity

trace/systrace: make start() return when tracing has started

Browse Source 
In SystraceCollector, start() returns after executing
subprocess.Popen() for systrace. That doesn't mean that systrace is
running though, the function can return even before systrace has had a
chance to execute anything. Therefore, when you run the command
you want to trace, systrace will miss the first seconds of the
execution.

Run systrace with -u to unbuffer its stdin and wait for it to print
"Starting tracing (stop with enter)" before returning.

Fixes #403
This commit is contained in:
Javi Merino 2019-07-30 14:43:58 +01:00 committed by Marc Bonnici
parent 986261bc7e
commit 71bd8b10ed
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
devlib/trace/systrace.py
View File

@ -107,7 +107,7 @@ class SystraceCollector(TraceCollector):
self._tmpfile = NamedTemporaryFile() self._tmpfile = NamedTemporaryFile()
# pylint: disable=attribute-defined-outside-init # pylint: disable=attribute-defined-outside-init
self.systrace_cmd = '{} -o {} -e {}'.format( self.systrace_cmd = 'python2 -u {} -o {} -e {}'.format(
self.systrace_binary, self.systrace_binary,
self._tmpfile.name, self._tmpfile.name,
self.target.adb_name self.target.adb_name
@ -137,9 +137,11 @@ class SystraceCollector(TraceCollector):
self._systrace_process = subprocess.Popen( self._systrace_process = subprocess.Popen(
self.systrace_cmd, self.systrace_cmd,
stdin=subprocess.PIPE, stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
shell=True, shell=True,
universal_newlines=True universal_newlines=True
) )
self._systrace_process.stdout.read(1)
def stop(self): def stop(self):
if not self._systrace_process: if not self._systrace_process: