Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f809ca9a authored by Mel Gorman's avatar Mel Gorman Committed by Ingo Molnar
Browse files

sched/numa: Track NUMA hinting faults on per-node basis 



This patch tracks what nodes numa hinting faults were incurred on.
This information is later used to schedule a task on the node storing
the pages most frequently faulted by the task.

Signed-off-by: default avatarMel Gorman <mgorman@suse.de>
Reviewed-by: default avatarRik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: default avatarPeter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-20-git-send-email-mgorman@suse.de


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent f307cd1a

include/linux/sched.h

+2 −0
Original line number Diff line number Diff line
@@ -1342,6 +1342,8 @@ struct task_struct { 
	unsigned int numa_scan_period_max;

	u64 node_stamp;			/* migration stamp  */

	struct callback_head numa_work;



	unsigned long *numa_faults;

#endif /* CONFIG_NUMA_BALANCING */



	struct rcu_head rcu;

kernel/sched/core.c

+3 −0
Original line number Diff line number Diff line
@@ -1634,6 +1634,7 @@ static void __sched_fork(struct task_struct *p) 
	p->numa_migrate_seq = p->mm ? p->mm->numa_scan_seq - 1 : 0;

	p->numa_scan_period = sysctl_numa_balancing_scan_delay;

	p->numa_work.next = &p->numa_work;

	p->numa_faults = NULL;

#endif /* CONFIG_NUMA_BALANCING */

}
@@ -1892,6 +1893,8 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev) 
	if (mm)

		mmdrop(mm);

	if (unlikely(prev_state == TASK_DEAD)) {

		task_numa_free(prev);



		/*

		 * Remove function-return probe instances associated with this

		 * task and put them back on the free list.

kernel/sched/fair.c

+10 −1
Original line number Diff line number Diff line
@@ -902,7 +902,14 @@ void task_numa_fault(int node, int pages, bool migrated) 
	if (!numabalancing_enabled)

		return;



	/* FIXME: Allocate task-specific structure for placement policy here */

	/* Allocate buffer to track faults on a per-node basis */

	if (unlikely(!p->numa_faults)) {

		int size = sizeof(*p->numa_faults) * nr_node_ids;



		p->numa_faults = kzalloc(size, GFP_KERNEL|__GFP_NOWARN);

		if (!p->numa_faults)

			return;

	}



	/*

	 * If pages are properly placed (did not migrate) then scan slower.
@@ -918,6 +925,8 @@ void task_numa_fault(int node, int pages, bool migrated) 
	}



	task_numa_placement(p);



	p->numa_faults[node] += pages;

}



static void reset_ptenuma_scan(struct task_struct *p)

kernel/sched/sched.h

+12 −0
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ 
#include <linux/spinlock.h>

#include <linux/stop_machine.h>

#include <linux/tick.h>

#include <linux/slab.h>



#include "cpupri.h"

#include "cpuacct.h"
@@ -555,6 +556,17 @@ static inline u64 rq_clock_task(struct rq *rq) 
	return rq->clock_task;

}



#ifdef CONFIG_NUMA_BALANCING

static inline void task_numa_free(struct task_struct *p)

{

	kfree(p->numa_faults);

}

#else /* CONFIG_NUMA_BALANCING */

static inline void task_numa_free(struct task_struct *p)

{

}

#endif /* CONFIG_NUMA_BALANCING */



#ifdef CONFIG_SMP



#define rcu_dereference_check_sched_domain(p) \