git: ff870b783f09 - main - sched_shim: restore kern.ccpu sysctl

The branch main has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=ff870b783f098cafd8b938379eada6b8cfe9a4fb

commit ff870b783f098cafd8b938379eada6b8cfe9a4fb
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2026-01-23 15:15:43 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2026-01-29 18:11:56 +0000

    sched_shim: restore kern.ccpu sysctl
    
    It is apparently should be considered part of the ABI, and is used by
    the base top(1).  But do not declare the ccpu variable in headers, it is
    needed only by 4bsd. So put the variable definition into sched_shim.c to
    make the kernel buildable without SCHED_4BSD.
    
    Reviewed by:    olce
    Tested by:      pho
    Sponsored by:   The FreeBSD Foundation
    MFC after:      1 week
    Differential revision:  https://reviews.freebsd.org/D54831
---
 sys/kern/sched_4bsd.c | 10 ++++++----
 sys/kern/sched_shim.c |  4 ++++
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/sys/kern/sched_4bsd.c b/sys/kern/sched_4bsd.c
index 11baf9d2bdfa..4c24d98173f3 100644
--- a/sys/kern/sched_4bsd.c
+++ b/sys/kern/sched_4bsd.c
@@ -436,10 +436,7 @@ maybe_preempt(struct thread *td)
 #define	loadfactor(loadav)	(2 * (loadav))
 #define	decay_cpu(loadfac, cpu)	(((loadfac) * (cpu)) / ((loadfac) + FSCALE))
 
-/* decay 95% of `ts_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */
-static fixpt_t	ccpu = 0.95122942450071400909 * FSCALE;	/* exp(-1/20) */
-SYSCTL_UINT(_kern_sched_4bsd, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0,
-    "Decay factor used for updating %CPU");
+extern fixpt_t ccpu;
 
 /*
  * If `ccpu' is not equal to `exp(-1/20)' and you still want to use the
@@ -638,6 +635,11 @@ resetpriority_thread(struct thread *td)
 static void
 sched_4bsd_setup(void)
 {
+	/*
+	 * Decay 95% of `ts_pctcpu' in 60 seconds; see CCPU_SHIFT
+	 * before changing.
+	 */
+	ccpu = 0.95122942450071400909 * FSCALE;	/* exp(-1/20) */
 
 	setup_runqs();
 
diff --git a/sys/kern/sched_shim.c b/sys/kern/sched_shim.c
index 816d0b44bb52..f6b1285830fd 100644
--- a/sys/kern/sched_shim.c
+++ b/sys/kern/sched_shim.c
@@ -199,3 +199,7 @@ SYSCTL_PROC(_kern_sched, OID_AUTO, available,
     CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
     NULL, 0, sysctl_kern_sched_available, "A",
     "List of available schedulers");
+
+fixpt_t ccpu;
+SYSCTL_UINT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0,
+    "Decay factor used for updating %CPU");