Those states are available since Linux 4.14 (kernel commits
8ef9925b02c23e3838d5 and 06eb61844d841d003). Before this
patch, they were shown as unknown.
This is mostly cosmetical.
Note that I is described in /proc/pid/status as just "idle", although
elsewhere it says it's an idle kernel thread. Let's have it as "idle"
for brevity.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
1. Remove PID field as it is useless.
2. Rewrite parseStat() to make it faster and more correct:
- do not use fmt.Scanf as it is very slow;
- avoid splitting data into 20+ fields, of which we only need 2;
- make sure to not panic on short lines and other bad input;
- add some bad input tests (some fail with old code);
- use LastIndexByte instead of LastIndex.
Benchmarks:
before (from the previous commit message):
> BenchmarkParseStat-4 116415 10804 ns/op
> BenchmarkParseRealStat-4 240 4781769 ns/op
after:
> BenchmarkParseStat-4 1164948 1068 ns/op
> BenchmarkParseRealStat-4 331 3458315 ns/op
We are seeing 10x speedup in a synthetic benchmark, and about 1.4x
speedup in a real world benchmark.
While at it, do not ignore any possible errors, and properly wrap those.
[v2: use pkg/errors more, remove t.Logf from test]
[v3: rebased; drop pkg/errors; gofumpt'ed]
[v4: rebased; improved description]
[v5: rebased; mention bad input tests, added second benchmark results]
[v6: remove PID field, do not use strings.Split, further speedup]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Most of these were false positives or cases where we want to ignore the
lint, but the change to the BPF generation is actually useful.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
GetProcessStartTime was deprecated over three Years ago in
439eaa3584, so we may as well remove
it now.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
And Stat_t.PID and Stat_t.Name while we're at it. Then use the new
.State property in runType to distinguish between running and
zombie/dead processes, since kill(2) does not [1]. With this change
we no longer claim Running status for zombie/dead processes.
I've also removed the kill(2) call from runType. It was originally
added in 13841ef3 (new-api: return the Running state only if the init
process is alive, 2014-12-23), but we've been accessing
/proc/[pid]/stat since 14e95b2a (Make state detection precise,
2016-07-05, #930), and with the /stat access the kill(2) check is
redundant.
I also don't see much point to the previously-separate
doesInitProcessExist, so I've inlined that logic in runType.
It would be nice to distinguish between "/proc/[pid]/stat doesn't
exist" and errors parsing its contents, but I've skipped that for the
moment.
The Running -> Stopped change in checkpoint_test.go is because the
post-checkpoint process is a zombie, and with this commit zombie
processes are Stopped (and no longer Running).
[1]: https://github.com/opencontainers/runc/pull/1483#issuecomment-307527789
Signed-off-by: W. Trevor King <wking@tremily.us>
