Currently, if the user stops the timer in a B.Loop benchmark loop, the
benchmark will run until it hits the timeout and fails.
Fix this by detecting that the timer is stopped and failing the
benchmark right away. We avoid making the fast path more expensive for
this check by "poisoning" the B.Loop iteration counter when the timer
is stopped so that it falls back to the slow path, which can check the
timer.
This causes b to escape from B.Loop, which is totally harmless because
it was already definitely heap-allocated. But it causes the
test/inline_testingbloop.go errorcheck test to fail. I don't think the
escape messages actually mattered to that test, they just had to be
matched. To fix this, we drop the debug level to -m=1, since -m=2
prints a lot of extra information for escaping parameters that we
don't want to deal with, and change one error check to allow b to
escape.
Fixes#72974.
Change-Id: I7d4abbb1ec1e096685514536f91ba0d581cca6b7
Reviewed-on: https://go-review.googlesource.com/c/go/+/659657
Auto-Submit: Austin Clements <austin@google.com>
Reviewed-by: Junyang Shao <shaojunyang@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/660558
Auto-Submit: Dmitri Shuralyov <dmitshur@google.com>
Currently, if a benchmark function returns prior to B.Loop() returning
false, we'll report a bogus result. While there was no way to detect
this with b.N-style benchmarks, one way b.Loop()-style benchmarks are
more robust is that we *can* detect it.
This CL adds a flag to B that tracks if B.Loop() has finished and
checks it after the benchmark completes. If there was an early exit
(not caused by another error), it reports a B.Error.
For #72974.
Change-Id: I731c1350e6df938c0ffa08fcedc11dc147e78854
Reviewed-on: https://go-review.googlesource.com/c/go/+/659656
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Austin Clements <austin@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Junyang Shao <shaojunyang@google.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/660557
Auto-Submit: Dmitri Shuralyov <dmitshur@google.com>
Currently, b.Loop uses b.N as the iteration count target. However,
since it updates the target as it goes, the behavior is quite
different from a b.N-style benchmark. To avoid user confusion, this CL
gives b.Loop a separate, unexported iteration count target. It ensures
b.N is 0 within the b.Loop loop to help catch misuses, and commits the
final iteration count to b.N only once the loop is done (as the
documentation states "After Loop returns false, b.N contains the total
number of iterations that ran, so the benchmark may use b.N to compute
other average metrics.")
Since there are now two variables used by b.Loop, we put them in an
unnamed struct. Also, we rename b.loopN to b.loop.i because this
variable tracks the current iteration index (conventionally "i"), not
the target (conventionally "n").
Unfortunately, a simple renaming causes B.Loop to be too large for the
inliner. Thus, we make one simplification to B.Loop to keep it under
the threshold. We're about to lean into that simplification anyway in
a follow-up CL, so this is just temporary.
For #72974.
Change-Id: Ide1c4f1b9ca37f300f3beb0e60ba6202331b183e
Reviewed-on: https://go-review.googlesource.com/c/go/+/659655
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Junyang Shao <shaojunyang@google.com>
Auto-Submit: Austin Clements <austin@google.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/660556
Auto-Submit: Dmitri Shuralyov <dmitshur@google.com>
B.Loop resets the timer on the first iteration so that setup code
isn't measured, but it currently leaves the timer running after the
last iteration, meaning that cleanup code will still be measured. Fix
this by stopping the timer when B.Loop returns false to indicate the
end of the benchmark.
Updates #61515
Change-Id: I0e0502cb2ce3c24cf872682b88d74e8be2c4529b
Reviewed-on: https://go-review.googlesource.com/c/go/+/635898
Reviewed-by: Junyang Shao <shaojunyang@google.com>
Auto-Submit: Austin Clements <austin@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
This moves the B.Loop test from package testing_test to package
testing, where it can check on more of the internals of the benchmark
state.
Updates #61515.
Change-Id: Ia32d7104526125c5e8a1e35dab7660008afcbf80
Reviewed-on: https://go-review.googlesource.com/c/go/+/635897
Auto-Submit: Austin Clements <austin@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Junyang Shao <shaojunyang@google.com>
