The branch main has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=bab24f22ba4518e640d14765dbd196e7709e1f0e
commit bab24f22ba4518e640d14765dbd196e7709e1f0e Author: Konstantin Belousov <[email protected]> AuthorDate: 2026-01-22 05:09:57 +0000 Commit: Konstantin Belousov <[email protected]> CommitDate: 2026-01-29 18:11:55 +0000 kern/sched_shim.c: Provide a scheduler selection machinery Reviewed by: olce Tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D54831 --- sys/amd64/amd64/machdep.c | 2 ++ sys/arm/arm/machdep.c | 3 +++ sys/arm64/arm64/machdep.c | 1 + sys/i386/i386/machdep.c | 1 + sys/kern/sched_shim.c | 49 +++++++++++++++++++++++++++++++++++++++++++ sys/powerpc/powerpc/machdep.c | 2 ++ sys/riscv/riscv/machdep.c | 2 ++ sys/sys/sched.h | 14 +++++++++++++ 8 files changed, 74 insertions(+) diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c index 8daa9c250db8..e56de986ccba 100644 --- a/sys/amd64/amd64/machdep.c +++ b/sys/amd64/amd64/machdep.c @@ -1352,6 +1352,8 @@ hammer_time(u_int64_t modulep, u_int64_t physfree) TUNABLE_INT_FETCH("hw.use_xsave", &use_xsave); } + sched_instance_select(); + link_elf_ireloc(); /* diff --git a/sys/arm/arm/machdep.c b/sys/arm/arm/machdep.c index 9532e19a11b3..0b395d42fc4a 100644 --- a/sys/arm/arm/machdep.c +++ b/sys/arm/arm/machdep.c @@ -523,6 +523,9 @@ initarm(struct arm_boot_params *abp) /* Do basic tuning, hz etc */ init_param1(); + sched_instance_select(); + /* link_elf_ireloc(); */ + /* * Allocate a page for the system page mapped to 0xffff0000 * This page will just contain the system vectors and can be diff --git a/sys/arm64/arm64/machdep.c b/sys/arm64/arm64/machdep.c index 6790f47a0f82..b1e22c900f3f 100644 --- a/sys/arm64/arm64/machdep.c +++ b/sys/arm64/arm64/machdep.c @@ -825,6 +825,7 @@ initarm(struct arm64_bootparams *abp) PCPU_SET(curthread, &thread0); PCPU_SET(midr, get_midr()); + sched_instance_select(); link_elf_ireloc(); #ifdef FDT try_load_dtb(); diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c index 3f659432552c..821265cc2911 100644 --- a/sys/i386/i386/machdep.c +++ b/sys/i386/i386/machdep.c @@ -1544,6 +1544,7 @@ init386(int first) /* Initialize preload_kmdp */ preload_initkmdp(!metadata_missing); + sched_instance_select(); link_elf_ireloc(); vm86_initialize(); diff --git a/sys/kern/sched_shim.c b/sys/kern/sched_shim.c index 079d7d73ec45..2dbb6b928961 100644 --- a/sys/kern/sched_shim.c +++ b/sys/kern/sched_shim.c @@ -15,6 +15,7 @@ #include <sys/proc.h> #include <sys/runq.h> #include <sys/sched.h> +#include <sys/sysctl.h> #include <machine/ifunc.h> const struct sched_instance *active_sched; @@ -92,3 +93,51 @@ DEFINE_SHIM0(sizeof_thread, int, sched_sizeof_thread) DEFINE_SHIM1(tdname, char *, sched_tdname, struct thread *, td) DEFINE_SHIM1(clear_tdname, void, sched_clear_tdname, struct thread *, td) DEFINE_SHIM0(init_ap, void, schedinit_ap) + +static char sched_name[32] = "ULE"; + +SET_DECLARE(sched_instance_set, struct sched_selection); + +void +sched_instance_select(void) +{ + struct sched_selection *s, **ss; + int i; + + TUNABLE_STR_FETCH("kern.sched.name", sched_name, sizeof(sched_name)); + SET_FOREACH(ss, sched_instance_set) { + s = *ss; + for (i = 0; s->name[i] == sched_name[i]; i++) { + if (s->name[i] == '\0') { + active_sched = s->instance; + return; + } + } + } + + /* + * No scheduler matching the configuration was found. If + * there is any scheduler compiled in, at all, use the first + * scheduler from the linker set. + */ + if (SET_BEGIN(sched_instance_set) < SET_LIMIT(sched_instance_set)) { + s = *SET_BEGIN(sched_instance_set); + active_sched = s->instance; + for (i = 0;; i++) { + sched_name[i] = s->name[i]; + if (s->name[i] == '\0') + break; + } + } +} + +void +schedinit(void) +{ + if (active_sched == NULL) + panic("Cannot find scheduler %s", sched_name); + active_sched->init(); +} + +SYSCTL_STRING(_kern_sched, OID_AUTO, name, CTLFLAG_RD, sched_name, 0, + "Scheduler name"); diff --git a/sys/powerpc/powerpc/machdep.c b/sys/powerpc/powerpc/machdep.c index f4a065e1ce46..04b3967ee110 100644 --- a/sys/powerpc/powerpc/machdep.c +++ b/sys/powerpc/powerpc/machdep.c @@ -83,6 +83,7 @@ #include <sys/reboot.h> #include <sys/reg.h> #include <sys/rwlock.h> +#include <sys/sched.h> #include <sys/signalvar.h> #include <sys/syscallsubr.h> #include <sys/sysctl.h> @@ -467,6 +468,7 @@ powerpc_init(vm_offset_t fdt, vm_offset_t toc, vm_offset_t ofentry, void *mdp, * Bring up MMU */ pmap_mmu_init(); + sched_instance_select(); link_elf_ireloc(); pmap_bootstrap(startkernel, endkernel); mtmsr(psl_kernset & ~PSL_EE); diff --git a/sys/riscv/riscv/machdep.c b/sys/riscv/riscv/machdep.c index 235cc651b87e..b213e8812bc7 100644 --- a/sys/riscv/riscv/machdep.c +++ b/sys/riscv/riscv/machdep.c @@ -479,6 +479,8 @@ parse_metadata(void) /* Initialize preload_kmdp */ preload_initkmdp(true); + sched_instance_select(); + /* link_elf_ireloc(); */ /* Read the boot metadata */ boothowto = MD_FETCH(preload_kmdp, MODINFOMD_HOWTO, int); diff --git a/sys/sys/sched.h b/sys/sys/sched.h index b733d4d07e34..27d0fc7d0c8d 100644 --- a/sys/sys/sched.h +++ b/sys/sys/sched.h @@ -68,6 +68,7 @@ #ifdef SCHED_STATS #include <sys/pcpu.h> #endif +#include <sys/linker_set.h> struct proc; struct thread; @@ -287,6 +288,19 @@ struct sched_instance { extern const struct sched_instance *active_sched; +struct sched_selection { + const char *name; + const struct sched_instance *instance; +}; +#define DECLARE_SCHEDULER(xsel_name, xsched_name, xsched_instance) \ + static struct sched_selection xsel_name = { \ + .name = xsched_name, \ + .instance = xsched_instance, \ + }; \ + DATA_SET(sched_instance_set, xsel_name); + +void sched_instance_select(void); + #endif /* _KERNEL */ /* POSIX 1003.1b Process Scheduling */
