diff options
| author | Michael Pratt <mpratt@google.com> | 2020-12-23 15:05:37 -0500 |
|---|---|---|
| committer | Michael Pratt <mpratt@google.com> | 2021-03-05 22:09:52 +0000 |
| commit | d85083911d6ea742901933a544467dad55bb381f (patch) | |
| tree | f8f826d01c3ff45af5908c8a1d71befe4439f97c /src/runtime/trace.go | |
| parent | 39bdd41d03725878f1fd6f8b500ba6700f03bdad (diff) | |
| download | go-d85083911d6ea742901933a544467dad55bb381f.tar.gz go-d85083911d6ea742901933a544467dad55bb381f.zip | |
runtime: encapsulate access to allgs
Correctly accessing allgs is a bit hairy. Some paths need to lock
allglock, some don't. Those that don't are safest using atomicAllG, but
usage is not consistent.
Rather than doing this ad-hoc, move all access* through forEachG /
forEachGRace, the locking and atomic versions, respectively. This will
make it easier to ensure safe access.
* markroot is the only exception, as it has a far-removed guarantee of
safe access via an atomic load of allglen far before actual use.
Change-Id: Ie1c7a8243e155ae2b4bc3143577380c695680e89
Reviewed-on: https://go-review.googlesource.com/c/go/+/279994
Trust: Michael Pratt <mpratt@google.com>
Run-TryBot: Michael Pratt <mpratt@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Diffstat (limited to 'src/runtime/trace.go')
| -rw-r--r-- | src/runtime/trace.go | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/src/runtime/trace.go b/src/runtime/trace.go index bcd0b9d56c..bfaa00ee58 100644 --- a/src/runtime/trace.go +++ b/src/runtime/trace.go @@ -221,7 +221,8 @@ func StartTrace() error { stackID := traceStackID(mp, stkBuf, 2) releasem(mp) - for _, gp := range allgs { + // World is stopped, no need to lock. + forEachGRace(func(gp *g) { status := readgstatus(gp) if status != _Gdead { gp.traceseq = 0 @@ -241,7 +242,7 @@ func StartTrace() error { } else { gp.sysblocktraced = false } - } + }) traceProcStart() traceGoStart() // Note: ticksStart needs to be set after we emit traceEvGoInSyscall events. |