This document seems to be out of date for many, many years. Even it has misspelled from the first day. ARCH_HASH_SCHED_TUNE should be ARCH_HAS_SCHED_TUNE ARCH_HASH_SCHED_DOMAIN should be ARCH_HAS_SCHED_DOMAIN But since v2.6.14, kernel completely deleted the relevant code and even arch_init_sched_domains() was deleted. Right now, kernel is asking architectures to call set_sched_topology() to override the default sched domains. Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Adrian Freund <adrian@xxxxxxxxx> Signed-off-by: Barry Song <song.bao.hua@xxxxxxxxxxxxx> --- Documentation/scheduler/sched-domains.rst | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) diff --git a/Documentation/scheduler/sched-domains.rst b/Documentation/scheduler/sched-domains.rst index 5c4b7f4f0062..434d4e7e86c5 100644 --- a/Documentation/scheduler/sched-domains.rst +++ b/Documentation/scheduler/sched-domains.rst @@ -69,15 +69,9 @@ The implementor should read comments in include/linux/sched.h: struct sched_domain fields, SD_FLAG_*, SD_*_INIT to get an idea of the specifics and what to tune. -Architectures may retain the regular override the default SD_*_INIT flags -while using the generic domain builder in kernel/sched/core.c if they wish to -retain the traditional SMT->SMP->NUMA topology (or some subset of that). This -can be done by #define'ing ARCH_HASH_SCHED_TUNE. - -Alternatively, the architecture may completely override the generic domain -builder by #define'ing ARCH_HASH_SCHED_DOMAIN, and exporting your -arch_init_sched_domains function. This function will attach domains to all -CPUs using cpu_attach_domain. +Architectures may override the generic domain builder and the default +SD_*_INIT flags by define'ing an array of sched_domain_topology_level and +calling set_sched_topology() with this array as the parameter. The sched-domains debugging infrastructure can be enabled by enabling CONFIG_SCHED_DEBUG. This enables an error checking parse of the sched domains -- 2.25.1