Comment 2 for bug 1626564

This issue was introduced with the massive kernel configurations changes between mainline kernels 4.7-rc4 and 4.7-rc5. While I have been working on it for a couple of weeks, I was never able to isolate the exact kernel configuration change cause. I am compiling a kernel now (4.8-rc7) reverting this change to test. This attachment has some tools I made to very very simply show the issue.

If I look at linux/Documentation/workqueue.txt and do:

echo workqueue:workqueue_queue_work > /sys/kernel/debug/tracing/set_event

and:

cat /sys/kernel/debug/tracing/trace_pipe > out.txt

with the issue, I get somwhere between 10,000 and 20,000 occurances of memcg_kmem_cache_create_func in the file (using my simple test method). Without the issue, I get 21, and an overall file size about 50 times smaller, for otherwise similar conditions. i.e. with the issue this stuff seems to go nuts.