git: 61ce73643f22 - main - NOTES: SMP: Move PREEMPTION out of the debugging options section
Date: Fri, 25 Sep 2026 15:39:56 UTC
The branch main has been updated by olce:
URL: https://cgit.FreeBSD.org/src/commit/?id=61ce73643f22f6f8273701eb978faa246bbca27d
commit 61ce73643f22f6f8273701eb978faa246bbca27d
Author: Olivier Certner <olce@FreeBSD.org>
AuthorDate: 2026-09-24 16:00:32 +0000
Commit: Olivier Certner <olce@FreeBSD.org>
CommitDate: 2026-09-25 15:21:49 +0000
NOTES: SMP: Move PREEMPTION out of the debugging options section
It has been activated by default for more than 20 years.
Reviewed by: mchoo, srcmgr (imp)
Fixes: 444ba945136b ("Switch the default scheduler to 4BSD...")
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D60012
---
sys/conf/NOTES | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index c9075d89c8ed..a4d60b709a6b 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -277,13 +277,15 @@ options RWLOCK_NOINLINE
# and WITNESS options.
options SX_NOINLINE
+# PREEMPTION allows the threads that are in the kernel to be preempted by
+# higher priority [interrupt] threads. It helps with interactivity
+# and allows interrupt threads to run sooner rather than waiting.
+options PREEMPTION
+
# SMP Debugging Options:
#
# CALLOUT_PROFILING enables rudimentary profiling of the callwheel data
# structure used as backend in callout(9).
-# PREEMPTION allows the threads that are in the kernel to be preempted by
-# higher priority [interrupt] threads. It helps with interactivity
-# and allows interrupt threads to run sooner rather than waiting.
# FULL_PREEMPTION instructs the kernel to preempt non-realtime kernel
# threads. Its sole use is to expose race conditions and other
# bugs during development. Enabling this option will reduce
@@ -303,7 +305,6 @@ options SX_NOINLINE
# a lock hierarchy violation occurs or if locks are held when going to
# sleep.
# WITNESS_SKIPSPIN disables the witness checks on spin mutexes.
-options PREEMPTION
options FULL_PREEMPTION
options WITNESS
options WITNESS_KDB