Disable as many timers as possible when DisableNetwork or when idle/hibernating

With #25373 (moved) and #25375 (moved), we should be using first-class timer objects for more and more of our timed events. We should have a way to mark timers that should be disabled when Tor is idle, or when DisableNetwork has been set. Then we should actually disable them, to lower the amount of wakeups that Tor performs under those circumstances.

changed milestone to %Tor: 0.3.4.x-final

added 034-included-20180328 034-roadmap-subtask 034-triage-20180328 component::core tor/tor milestone::Tor: 0.3.4.x-final owner::dgoulet parent::25500 priority::medium resolution::implemented reviewer::nickm severity::normal sponsor::8 status::closed type::defect labels

(There should be one subticket to build this system, and several subtickets to apply it as needed)

Setting master ticket parent ID.

Trac:
Parent: N/A to #25500 (moved)

Trac:
Keywords: N/A deleted, 034-roadmap-subtask added

Trac:
Keywords: N/A deleted, 034-triage-20180328 added

Trac:
Keywords: N/A deleted, 034-included-20180328 added

Note that many of the periodic timer callbacks already contain "if (!net_is_disabled(...))"

Trac:
Owner: N/A to dgoulet
Status: new to assigned

https://github.com/torproject/tor/pull/60

See branch: ticket25376_034_01

Trac:
Status: assigned to needs_review
Reviewer: N/A to nickm

I think this is good; we may have gotten some of the 0 vs NEEDS_NET flags wrong, but I can't find any obvious problems there.

This needs a changes file, though. (And did we remember to put one on #25762 (moved) ? Maybe they can both share a single changes file.)

Please feel free to put this in merge_ready once a changes_file exists.

Trac:
Status: needs_review to needs_revision

Pushed as a fixup commit. Feel free to tweak the text. I think it is OK but maybe there is a better English that could be used for some of it ;).

Trac:
Status: needs_revision to merge_ready

squashed & merged to master!

Don't worry about the English; usually I do the changes-file cleanups when I'm making the changelogs.

Trac:
Status: merge_ready to closed
Resolution: N/A to implemented

closed

mentioned in issue #25762 (moved)

mentioned in issue #25937 (moved)

moved to tpo/core/tor#25376 (closed)