mirror/freebsd
1
0
Fork 0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-20 11:11:24 +00:00
Code Issues Releases Activity

setusercontext(): Fix gap when setting a realtime-class priority

Browse Source 
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
MFC after:              2 weeks
Sponsored by:           Kumacom SAS
Differential Revision:  https://reviews.freebsd.org/D40339
This commit is contained in:
Olivier Certner 2023-05-25 09:10:27 +02:00 committed by Ed Maste
parent ebaea1bcd2
commit bd572be784
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
lib/libutil/login_class.c
View File

@ -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",