diff options
| author | Olivier Certner <olce.freebsd@certner.fr> | 2023-05-25 07:10:27 +0000 |
|---|---|---|
| committer | Olivier Certner <olce@FreeBSD.org> | 2023-12-21 13:38:46 +0000 |
| commit | 831792fc07cadd1aa3bc404843f45b8c2982b1bf (patch) | |
| tree | 3c4182b315b4c47ef5675fa9178eace99bc2326e | |
| parent | f63da970458592f7488796da4e8c07f9e5314b31 (diff) | |
setusercontext(): Fix gap when setting a realtime-class priority
The login.conf's "priority" capability allows to set priorities in the
idle or realtime classes in addition to the classical nice values (-20
to 20), through a natural extension where values greater than 20 put the
processes in the idle class (with priority adjusted within RTP_PRIO_MIN
and RTP_PRIO_MAX, 21 being converted to 0, 22 to 1, etc.) and values
lower than -20 put the process in the realtime class (with priority
adjusted within RTP_PRIO_MIN and RTP_PRIO_MAX, -21 being converted to
RTP_PRIO_MAX (31), -22 to 30, etc.).
Before this fix, in the latter case (realtime class), -21 was converted
to 30, and RTP_PRIO_MAX (31) could never be specified.
While here, change the priority computation for the idle-class case to
be symmetrical and use RTP_PRIO_MIN (in practice, this changes nothing
at all, since RTP_PRIO_MIN is 0; but this is the correct theoretical
formula, which would work as well with other values of RTP_PRIO_MIN).
PR: 271727
Reviewed by: imp, kib
Sponsored by: Kumacom SAS
Differential Revision: https://reviews.freebsd.org/D40339
(cherry picked from commit bd572be78436473a2ad4c1b78728b739c74ef238)
Approved by: markj (mentor)
| -rw-r--r-- | lib/libutil/login_class.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/lib/libutil/login_class.c b/lib/libutil/login_class.c index f561479690c1..90a3ec5d106a 100644 --- a/lib/libutil/login_class.c +++ b/lib/libutil/login_class.c @@ -452,7 +452,7 @@ setusercontext(login_cap_t *lc, const struct passwd *pwd, uid_t uid, unsigned in if (p > PRIO_MAX) { rtp.type = RTP_PRIO_IDLE; - p -= PRIO_MAX + 1; + p += RTP_PRIO_MIN - (PRIO_MAX + 1); rtp.prio = p > RTP_PRIO_MAX ? RTP_PRIO_MAX : p; if (rtprio(RTP_SET, 0, &rtp)) syslog(LOG_WARNING, "rtprio '%s' (%s): %m", @@ -460,7 +460,7 @@ setusercontext(login_cap_t *lc, const struct passwd *pwd, uid_t uid, unsigned in lc ? lc->lc_class : LOGIN_DEFCLASS); } else if (p < PRIO_MIN) { rtp.type = RTP_PRIO_REALTIME; - p -= PRIO_MIN - RTP_PRIO_MAX; + p += RTP_PRIO_MAX - (PRIO_MIN - 1); rtp.prio = p < RTP_PRIO_MIN ? RTP_PRIO_MIN : p; if (rtprio(RTP_SET, 0, &rtp)) syslog(LOG_WARNING, "rtprio '%s' (%s): %m", |