Commit cfe7ddcb authored by Valentin Schneider's avatar Valentin Schneider Committed by Ingo Molnar
Browse files

ARM, sched/topology: Remove SD_SHARE_POWERDOMAIN 



This flag was introduced in 2014 by commit:

  d77b3ed5 ("sched: Add a new SD_SHARE_POWERDOMAIN for sched_domain")

but AFAIA it was never leveraged by the scheduler. The closest thing I can
think of is EAS caring about frequency domains, and it does that by
leveraging performance domains.

Remove the flag. No change in functionality is expected.

Suggested-by: default avatarMorten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: default avatarValentin Schneider <valentin.schneider@arm.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Reviewed-by: default avatarDietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20200817113003.20802-2-valentin.schneider@arm.com
parent 18445bf4

arch/arm/kernel/topology.c

+1 −1
Original line number Diff line number Diff line
@@ -243,7 +243,7 @@ topology_populated: 


static inline int cpu_corepower_flags(void)

{

	return SD_SHARE_PKG_RESOURCES  | SD_SHARE_POWERDOMAIN;

	return SD_SHARE_PKG_RESOURCES;

}



static struct sched_domain_topology_level arm_topology[] = {

include/linux/sched/topology.h

+6 −7
Original line number Diff line number Diff line
@@ -18,13 +18,12 @@ 
#define SD_WAKE_AFFINE		0x0010	/* Wake task to waking CPU */

#define SD_ASYM_CPUCAPACITY	0x0020  /* Domain members have different CPU capacities */

#define SD_SHARE_CPUCAPACITY	0x0040	/* Domain members share CPU capacity */

#define SD_SHARE_POWERDOMAIN	0x0080	/* Domain members share power domain */

#define SD_SHARE_PKG_RESOURCES	0x0100	/* Domain members share CPU pkg resources */

#define SD_SERIALIZE		0x0200	/* Only a single load balancing instance */

#define SD_ASYM_PACKING		0x0400  /* Place busy groups earlier in the domain */

#define SD_PREFER_SIBLING	0x0800	/* Prefer to place tasks in a sibling domain */

#define SD_OVERLAP		0x1000	/* sched_domains of this level overlap */

#define SD_NUMA			0x2000	/* cross-node balancing */

#define SD_SHARE_PKG_RESOURCES	0x0080	/* Domain members share CPU pkg resources */

#define SD_SERIALIZE		0x0100	/* Only a single load balancing instance */

#define SD_ASYM_PACKING		0x0200  /* Place busy groups earlier in the domain */

#define SD_PREFER_SIBLING	0x0400	/* Prefer to place tasks in a sibling domain */

#define SD_OVERLAP		0x0800	/* sched_domains of this level overlap */

#define SD_NUMA			0x1000	/* cross-node balancing */



#ifdef CONFIG_SCHED_SMT

static inline int cpu_smt_flags(void)

kernel/sched/topology.c

+3 −7
Original line number Diff line number Diff line
@@ -148,8 +148,7 @@ static int sd_degenerate(struct sched_domain *sd) 
			 SD_BALANCE_EXEC |

			 SD_SHARE_CPUCAPACITY |

			 SD_ASYM_CPUCAPACITY |

			 SD_SHARE_PKG_RESOURCES |

			 SD_SHARE_POWERDOMAIN)) {

			 SD_SHARE_PKG_RESOURCES)) {

		if (sd->groups != sd->groups->next)

			return 0;

	}
@@ -180,8 +179,7 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent) 
			    SD_ASYM_CPUCAPACITY |

			    SD_SHARE_CPUCAPACITY |

			    SD_SHARE_PKG_RESOURCES |

			    SD_PREFER_SIBLING |

			    SD_SHARE_POWERDOMAIN);

			    SD_PREFER_SIBLING);

		if (nr_node_ids == 1)

			pflags &= ~SD_SERIALIZE;

	}
@@ -1292,7 +1290,6 @@ int __read_mostly node_reclaim_distance = RECLAIM_DISTANCE; 
 *   SD_SHARE_CPUCAPACITY   - describes SMT topologies

 *   SD_SHARE_PKG_RESOURCES - describes shared caches

 *   SD_NUMA                - describes NUMA topologies

 *   SD_SHARE_POWERDOMAIN   - describes shared power domain

 *

 * Odd one out, which beside describing the topology has a quirk also

 * prescribes the desired behaviour that goes along with it:
@@ -1303,8 +1300,7 @@ int __read_mostly node_reclaim_distance = RECLAIM_DISTANCE; 
	(SD_SHARE_CPUCAPACITY	|	\

	 SD_SHARE_PKG_RESOURCES |	\

	 SD_NUMA		|	\

	 SD_ASYM_PACKING	|	\

	 SD_SHARE_POWERDOMAIN)

	 SD_ASYM_PACKING)



static struct sched_domain *

sd_init(struct sched_domain_topology_level *tl,

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