Commit graph

3 commits

Author SHA1 Message Date
Christopher Ferris
f30a810bce Use async safe logging in signal handlers.
Test: Boot on bullhead.
Test: Ran the libbacktrace tests on bullhead.
Test: Added a temporary log message in the signal handler, and ran the
Test: backtrace tests.
Change-Id: I0a6888c9f311af2c8cc7fbb4929315911bd2bb3c
2017-05-04 17:15:17 -07:00
Christopher Ferris
2d09171758 Modify the code to avoid potential deadlocks.
If the signal to dump a thread is never delivered, then it's
possible for a deadlock. The signal handler is responsible for
unlocking and deleting the ThreadEntry created for the pid/tid
combination. This means if the signal is lost, the ThreadEntry
gets stuck locked and never deleted. If a second attempt to get
a backtrace of this thread occurs, there is a deadlock.

Also, decrease the timeout from 10 seconds to 5 seconds. The original
10 seconds was because the unwind was actually done in the signal
handler. Now the signal handler does nothing but copy the ucontext
structure and let the caller do the unwind.

Bug: 21086132
Change-Id: Idc735dbf6147ec879d35bd4f034c5d227e26a98d
2015-06-01 13:51:51 -07:00
Christopher Ferris
2c43cff01d Refactor the code.
The object hierarchy was confusing and convoluted. This removes
a lot of unnecessary code, and consolidates the BacktraceCurrent
and BacktraceThread code into BacktraceCurrent.

Change-Id: I01c8407d493712a48169df49dd3ff46db4a7c3ae
2015-03-31 10:51:44 -07:00