On some profiles of Andrea's from #11332, I found that a great deal
of time can still be attributed to functions called from
update_router_have_minimum_dir_info(). This is making our
digestmap, tor_memeq, and siphash functions take a much bigger
portion of runtime than they really should.
If we're calling update_router_have_minimum_dir_info() too often,
that's because we're calling router_dir_info_changed() too often.
And it looks like most of the callers of router_dir_info_changed()
are coming as tail-calls from router_set_status() as invoked by
channel_do_open_actions().
But we don't need to call router_dir_info_changed() so much! (I'm
not quite sure we need to call it from here at all, but...) Surely
we don't need to call it from router_set_status when the router's
status has not actually changed.
This patch makes us call router_dir_info_changed() from
router_set_status only when we are changing the router's status.
Fix for bug 12170. This is leftover from our fix back in 273ee3e81
in 0.1.2.1-alpha, where we started caching the value of
update_router_have_minimum_dir_info().
tor_memeq has started to show up on profiles, and this is one of the
most frequent callers of that function, appearing as it does on every
cell handled for entry or exit.
59f9097d5c introduced tor_memneq here;
it went into Tor 0.2.1.31. Fixes part of 12169.
I've copied the entries from changes/, labeled the ones that also
appeared in 0.2.4.22, sorted them lightly with a python script
(added to maint), and combined sections with the same name.
I didn't combine sections without a description (e.g. "Minor
bugfixes:"), since we'll probably add a description to those.
Without this fix, when running with bridges, we would try fetching
directory info far too early, and have up to a 60 second delay if we
started with bridge descriptors available.
Fixes bug 11965. Fix on 0.2.3.6-alpha, arma thinks.
The old cache had problems:
* It needed to be manually preloaded. (It didn't remember any
address you didn't tell it to remember)
* It was AF_INET only.
* It looked at its cache even if the sandbox wasn't turned on.
* It couldn't remember errors.
* It had some memory management problems. (You can't use memcpy
to copy an addrinfo safely; it has pointers in.)
This patch fixes those issues, and moves to a hash table.
Fixes bug 11970; bugfix on 0.2.5.1-alpha.
These are needed under some circumstances if we are running with
expensive-hardening and sandbox at the same time.
fixes 11477, bugfix on 0.2.5.4-alpha (where we introduced
expensive-hardening)
None of the things we might exec() can possibly run under the
sanbox, so rather than crash later, we have to refuse to accept the
configuration nice and early.
The longer-term solution is to have an exec() helper, but wow is
that risky.
fixes 12043; bugfix on 0.2.5.1-alpha
