1) I forgot that I had another selftest to stress test the ftrace
instance creation. It was actually suppose to go into the 4.6
merge window, but I never committed it. I almost forgot about it
again, but noticed it was missing from your tree.
2) Soumya PN sent me a clean up patch to not disable interrupts when
taking the tasklist_lock for read, as it's unnecessary because
that lock is never taken for write in irq context.
3) Newer gcc's can cause the jump in the function_graph code to the
global ftrace_stub label to be a short jump instead of a long one.
As that jump is dynamically converted to jump to the trace code to
do function graph tracing, and that conversion expects a long jump
it can corrupt the ftrace_stub itself (it's directly after that call).
One way to prevent gcc from using a short jump is to declare the
ftrace_stub as a weak function, which we do here to keep gcc from
optimizing too much.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJXQhYQAAoJEKKk/i67LK/82pAH/3XzRCP366HqWnKdvluPB8vX
UnVoXGAX1Eh2ZpvlPIJBXNYOZlnGRMMMAoeI+su31FoJHrzTzfGXvRynTkZPFZtd
XakvHfACjtGtvi2MuCN1t9/d1ty/ob2o05KB9qc+JRlzHM09qTL/HX8hwZeEsMQ4
NYgEY4Y727LOSCrJieLktchpwtie77q8Wq25oiWIVWOyDjpCsPnZyaOqaQSANot9
Gd00cixbMam7Ba1BjoRsRQZaT2pYZ8vt7HDXDBfAOW1oOjalWARLhRg/zww1V3WD
DEptuEeyAgMJS3v76Z6Sbk/QM7hyGUWCcmC2qaN1yc2n1Sh+zBOiN1eyiiUh/2U=
=ERxv
-----END PGP SIGNATURE-----
Merge tag 'trace-v4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull motr tracing updates from Steven Rostedt:
"Three more changes.
- I forgot that I had another selftest to stress test the ftrace
instance creation. It was actually suppose to go into the 4.6
merge window, but I never committed it. I almost forgot about it
again, but noticed it was missing from your tree.
- Soumya PN sent me a clean up patch to not disable interrupts when
taking the tasklist_lock for read, as it's unnecessary because that
lock is never taken for write in irq context.
- Newer gcc's can cause the jump in the function_graph code to the
global ftrace_stub label to be a short jump instead of a long one.
As that jump is dynamically converted to jump to the trace code to
do function graph tracing, and that conversion expects a long jump
it can corrupt the ftrace_stub itself (it's directly after that
call). One way to prevent gcc from using a short jump is to
declare the ftrace_stub as a weak function, which we do here to
keep gcc from optimizing too much"
* tag 'trace-v4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace/x86: Set ftrace_stub to weak to prevent gcc from using short jumps to it
ftrace: Don't disable irqs when taking the tasklist_lock read_lock
ftracetest: Add instance created, delete, read and enable event test
7639dad93a