MFC r319590:

MFC r320974-r320975, r321001, r321206

r320974:
Use ATF cleanup routines in aio_test.c

Remove aio_test's legacy timeout handling and cleanup routines. Instead,
use ATF's builtin capabilities. ATF automatically cleans up newly created
files, too, so we don't have to explicitly unlink them. The only tests than
need a cleanup routine are the md(4) tests, which must destroy their md
device.

Reviewed by: jhb
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D11468

r320975:
Add tests for aio(4) completion notification via signals and threads

Reviewed by: jhb
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D11468

r321001:
Fix the build with GCC after r320975

Reported by: pfg
X-MFC-With: 320975
Sponsored by: Spectra Logic Corp

r321206:
Remove dead code that was killed by r320975

Reported by: Coverity
CID: 1377977
X-MFC-With: 320975
Sponsored by: Spectra Logic Corp

MFC r318180:

Mark all md tests as requiring unsafe AIO in order to function

These tests have been flapping (failing<->passing) on Jenkins for months.
It passes reliably for me if unsafe AIO is permitted, but it doesn't
pass on Jenkins reliably if unsafe AIO is disabled (the current default).

Mark the tests as requiring unsafe AIO to mitigate the intermittent
failures when unsafe AIO isn't permitted. If the kernel code is changed
to reliably function with md(4) devices using unsafe AIO, this commit can
be reverted.

PR: 217261

MFC r312919 (by rwatson)

Fix build of aio_test on MIPS, where the compiler warns about the local
variable 'err' shadowing the global function err(3). Which it does.

Sponsored by: DARPA, AFRL
Approved by: re

MFC r312913,r318100,r318107:

r312913 (by asomers):

Improve the aio tests

* Add tests for aio_suspend(2).
* Add tests for polled completion notification.
* Test the full matrix of file descriptor types and completion notification
mechanisms.
* Don't bother with mkstemp, because ATF runs every test in its own temp dir.
* Fix some typos.
* Remove extraneous ATF_REQUIRE_KERNEL_MODULE calls.

r318100:

style(9): move function definition curly braces to column 0

r318107:

Remove unused constant (PATH_TEMPLATE)

It was made unnecessary in r312913.

MFC with: r312913

MFC 303406,303501: Fix panic when using aio_fsync().

303406:
Adjust tests in fsync job scheduling loop to reduce indentation.

303501:
Fix locking issues with aio_fsync().

- Use correct lock in aio_cancel_sync when dequeueing job.
- Add _locked variants of aio_set/clear_cancel_function and use those
to avoid lock recursion when adding and removing fsync jobs to the
per-process sync queue.
- While here, add a basic test for aio_fsync().

PR: 211390
Approved by: re (kib)