Resources allocated by cpuworker weren't being freed on clean shutdown.
This applies for worker threads, worker thread pool, reply queue, reply
event, ...
We mark the intro circuit with a new flag saying that the pow is
in the cpuworker queue. When the cpuworker comes back, it either
has a solution, in which case we proceed with sending the intro1
cell, or it has no solution, in which case we unmark the intro
circuit and let the whole process restart on the next iteration of
connection_ap_handshake_attach_circuit().
We cap our number of CPU worker threads to at least 2 even if we have a
single core. But also, before we used to always add one extra thread
regardless of the number of core.
This meant that we were off when re-using the get_num_cpus() function
when calculating our onionskin work overhead because we were always off
by one.
This commit makes it that we always use the number of thread our actual
thread pool was configured with.
Fixes#40719
Signed-off-by: David Goulet <dgoulet@torproject.org>
Fun fact: these files used to be called log.[ch] until we ran into
conflicts with systems having a log.h file. But now that we always
include "lib/log/log.h", we should be fine.