[tip:,sched/core] x86/sched/itmt: Give all SMT siblings of a core the same priority
Commit Message
The following commit has been merged into the sched/core branch of tip:
Commit-ID: 046a5a95c3b0425cfe79e43021d8ee90c1c4f8c9
Gitweb: https://git.kernel.org/tip/046a5a95c3b0425cfe79e43021d8ee90c1c4f8c9
Author: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
AuthorDate: Thu, 06 Apr 2023 13:31:47 -07:00
Committer: Peter Zijlstra <peterz@infradead.org>
CommitterDate: Mon, 08 May 2023 10:58:38 +02:00
x86/sched/itmt: Give all SMT siblings of a core the same priority
X86 does not have the SD_ASYM_PACKING flag in the SMT domain. The scheduler
knows how to handle SMT and non-SMT cores of different priority. There is
no reason for SMT siblings of a core to have different priorities.
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Len Brown <len.brown@intel.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Link: https://lore.kernel.org/r/20230406203148.19182-12-ricardo.neri-calderon@linux.intel.com
---
arch/x86/kernel/itmt.c | 23 +++++------------------
1 file changed, 5 insertions(+), 18 deletions(-)
@@ -165,32 +165,19 @@ int arch_asym_cpu_priority(int cpu)
/**
* sched_set_itmt_core_prio() - Set CPU priority based on ITMT
- * @prio: Priority of cpu core
- * @core_cpu: The cpu number associated with the core
+ * @prio: Priority of @cpu
+ * @cpu: The CPU number
*
* The pstate driver will find out the max boost frequency
* and call this function to set a priority proportional
- * to the max boost frequency. CPU with higher boost
+ * to the max boost frequency. CPUs with higher boost
* frequency will receive higher priority.
*
* No need to rebuild sched domain after updating
* the CPU priorities. The sched domains have no
* dependency on CPU priorities.
*/
-void sched_set_itmt_core_prio(int prio, int core_cpu)
+void sched_set_itmt_core_prio(int prio, int cpu)
{
- int cpu, i = 1;
-
- for_each_cpu(cpu, topology_sibling_cpumask(core_cpu)) {
- int smt_prio;
-
- /*
- * Ensure that the siblings are moved to the end
- * of the priority chain and only used when
- * all other high priority cpus are out of capacity.
- */
- smt_prio = prio * smp_num_siblings / (i * i);
- per_cpu(sched_core_priority, cpu) = smt_prio;
- i++;
- }
+ per_cpu(sched_core_priority, cpu) = prio;
}