Messages in this thread Patch in this message | | | From | Ricardo Neri <> | Subject | [PATCH v4 09/12] sched/topology: Remove SHARED_CHILD from ASYM_PACKING | Date | Thu, 6 Apr 2023 13:31:45 -0700 |
| |
Only x86 and Power7 use ASYM_PACKING. They use it differently.
Power7 has cores of equal priority, but the SMT siblings of a core have different priorities. Parent scheduling domains do not need (nor have) the ASYM_PACKING flag. SHARED_CHILD is not needed. Using SHARED_PARENT would cause the topology debug code to complain.
X86 has cores of different priority, but all the SMT siblings of the core have equal priority. It needs ASYM_PACKING at the MC level, but not at the SMT level (it also needs it at upper levels if they have scheduling groups of different priority). Removing ASYM_PACKING from the SMT domain causes the topology debug code to complain.
Remove SHARED_CHILD for now. We still need a topology check that satisfies both architectures.
Cc: Ben Segall <bsegall@google.com> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Ionela Voinescu <ionela.voinescu@arm.com> Cc: Len Brown <len.brown@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tim C. Chen <tim.c.chen@intel.com> Cc: Valentin Schneider <vschneid@redhat.com> Cc: x86@kernel.org Cc: linux-kernel@vger.kernel.org Tested-by: Zhang Rui <rui.zhang@intel.com> Suggested-by: Valentin Schneider <vschneid@redhat.com> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> --- Changes since v3: * Removed spurious space.
Changes since v2: * Introduced this patch.
Changes since v1: * N/A --- include/linux/sched/sd_flags.h | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/include/linux/sched/sd_flags.h b/include/linux/sched/sd_flags.h index 57bde66d95f7..fad77b5172e2 100644 --- a/include/linux/sched/sd_flags.h +++ b/include/linux/sched/sd_flags.h @@ -132,12 +132,9 @@ SD_FLAG(SD_SERIALIZE, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS) /* * Place busy tasks earlier in the domain * - * SHARED_CHILD: Usually set on the SMT level. Technically could be set further - * up, but currently assumed to be set from the base domain - * upwards (see update_top_cache_domain()). * NEEDS_GROUPS: Load balancing flag. */ -SD_FLAG(SD_ASYM_PACKING, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) +SD_FLAG(SD_ASYM_PACKING, SDF_NEEDS_GROUPS) /* * Prefer to place tasks in a sibling domain -- 2.25.1
| |