diff options
| author |   anton <anton@openbsd.org> | 2020-05-25 14:00:15 +0000 |
|---|---|---|
| committer | anton <anton@openbsd.org> | 2020-05-25 14:00:15 +0000 |
| commit | a96435ee8348abf4f4e53f24b98434bd7f0ff368 (patch) | |
| tree | d0cc4a9b03808ac02e371ab6c1b96d0394ccdd16 /sys/dev/kcov.c | |
| parent | Use <dev/clock_subr.h> in mcclock(4). (diff) | |
| download | wireguard-openbsd-a96435ee8348abf4f4e53f24b98434bd7f0ff368.tar.xz wireguard-openbsd-a96435ee8348abf4f4e53f24b98434bd7f0ff368.zip | |
Add a comment explaining the interaction between kcovclose() and
kcov_exit().
Diffstat (limited to 'sys/dev/kcov.c')
| -rw-r--r-- | sys/dev/kcov.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/sys/dev/kcov.c b/sys/dev/kcov.c index fa1ce1b6dc5..12d94dbca1e 100644 --- a/sys/dev/kcov.c +++ b/sys/dev/kcov.c @@ -1,4 +1,4 @@ -/* $OpenBSD: kcov.c,v 1.18 2020/05/17 08:46:05 anton Exp $ */ +/* $OpenBSD: kcov.c,v 1.19 2020/05/25 14:00:15 anton Exp $ */ /* * Copyright (c) 2018 Anton Lindqvist <anton@openbsd.org> @@ -235,6 +235,10 @@ kcovclose(dev_t dev, int flag, int mode, struct proc *p) return (EINVAL); if (kd->kd_state == KCOV_STATE_TRACE) { + /* + * Another thread is currently using the kcov descriptor, + * postpone freeing to kcov_exit(). + */ kd->kd_state = KCOV_STATE_DYING; kd->kd_mode = KCOV_MODE_NONE; } else { |