The current test often doesn't actually generate enough interleaving
to result in multiple log shards. This CL rewrites this test to
forcibly create at least 10 log shards with interleaved log messages.
It also tests dlog's robustness to being held across M and P switches.
Change-Id: Ia913b17c0392384ff679832047f359945669bb15
Reviewed-on: https://go-review.googlesource.com/c/go/+/600699
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Auto-Submit: Austin Clements <austin@google.com>
Now that we're actually testing debuglog in the regular build
configuration, it's far less important that we take the time to
rebuild with the debuglog tag.
Change-Id: I62bfd494ccb99087f35851c4476238b39ef40dec
Reviewed-on: https://go-review.googlesource.com/c/go/+/600698
Reviewed-by: Carlos Amedee <carlos@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Currently, the debuglog tests only run when the debuglog build tag is
set because, until the last few CLs, all of debuglog was compiled away
without that build tag. This causes two annoying problems:
1. The tests basically never run, because we don't regularly test this
configuration.
2. If you do turn on the debuglog build tag, it's probably because
you're adding debuglogs into the runtime, which are very likely to
mess up these tests, so you wind up disabling the tests and they,
again, don't get coverage.
Now we've set things up so the debuglog implementation is always
accessible, if you ask nicely enough. So we can switch these tests to
run when the tag is *not* set, and turn off when the tag *is* set (and
you're probably adding actual log statements).
Change-Id: Ib68d7a5022d4f5db96e9c7c8010cbef21d11fe11
Reviewed-on: https://go-review.googlesource.com/c/go/+/600697
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
CL 428157 and CL 428759 switched debuglog to using unsafe.String and
unsafe.Slice, which broke the build with -tags=debuglog because this is
a no write barrier context, but runtime.unsafeString and unsafeSlice can
panic, which includes write barriers.
We could add a panicCheck1 path to these functions to reallow write
barriers, but it is a big mess to pass around the caller PC,
particularly since the compiler generates calls. It is much simpler to
just avoid unsafe.String and Slice.
Also add a basic test to build the runtime with -tags=debuglog to help
avoid future regressions.
For #54854.
Change-Id: I702418b986fbf189664e9aa4f40bc7de4d9e7781
Reviewed-on: https://go-review.googlesource.com/c/go/+/443380
Run-TryBot: Michael Pratt <mpratt@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
This adds an internal runtime debug log. It uses per-M time-stamped
ring buffers of binary log records. On panic, these buffers are
collected, interleaved, and printed.
The entry-point to the debug log is a new "dlog" function. dlog is
designed so it can be used even from very constrained corners of the
runtime such as signal handlers or inside the write barrier.
The facility is only enabled if the debuglog build tag is set.
Otherwise, it compiles away to a no-op implementation.
The debug log format is also designed so it would be reasonable to
decode from a core dump, though this hasn't been implemented.
Change-Id: I6e2737c286358e97a0d8091826498070b95b66a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/157997
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Austin Clements
Michael Pratt
cuiweixie