Commit 10864a9e authored Jun 20, 2018 by Srikar Dronamraju Committed by Ingo Molnar Jul 25, 2018

sched/numa: Remove unused task_capacity from 'struct numa_stats'



The task_capacity field in 'struct numa_stats' is redundant.
Also move nr_running for better packing within the struct.

No functional changes.

Running SPECjbb2005 on a 4 node machine and comparing bops/JVM
JVMS  LAST_PATCH  WITH_PATCH  %CHANGE
16    25308.6     25377.3     0.271
1     72964       72287       -0.92

Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Rik van Riel <riel@surriel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1529514181-9842-9-git-send-email-srikar@linux.vnet.ibm.com


Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent 0ee7e74d

kernel/sched/fair.c

+3 −5

Original line number	Diff line number	Diff line
		@@ -1450,14 +1450,12 @@ static unsigned long capacity_of(int cpu);

		/* Cached statistics for all CPUs within a node */
		struct numa_stats {
		unsigned long nr_running;
		unsigned long load;

		/* Total compute capacity of CPUs on a node */
		unsigned long compute_capacity;

		/* Approximate capacity in terms of runnable tasks on a node */
		unsigned long task_capacity;
		unsigned int nr_running;
		int has_free_capacity;
		};

		@@ -1495,9 +1493,9 @@ static void update_numa_stats(struct numa_stats *ns, int nid)
		smt = DIV_ROUND_UP(SCHED_CAPACITY_SCALE * cpus, ns->compute_capacity);
		capacity = cpus / smt; /* cores */

		ns->task_capacity = min_t(unsigned, capacity,
		capacity = min_t(unsigned, capacity,
		DIV_ROUND_CLOSEST(ns->compute_capacity, SCHED_CAPACITY_SCALE));
		ns->has_free_capacity = (ns->nr_running < ns->task_capacity);
		ns->has_free_capacity = (ns->nr_running < capacity);
		}

		struct task_numa_env {