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Message-ID: <53297F10.3050106@arm.com>
Date: Wed, 19 Mar 2014 11:27:12 +0000
From: Dietmar Eggemann <dietmar.eggemann@....com>
To: Vincent Guittot <vincent.guittot@...aro.org>,
"peterz@...radead.org" <peterz@...radead.org>,
"mingo@...nel.org" <mingo@...nel.org>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
"preeti@...ux.vnet.ibm.com" <preeti@...ux.vnet.ibm.com>,
"tony.luck@...el.com" <tony.luck@...el.com>,
"fenghua.yu@...el.com" <fenghua.yu@...el.com>,
"schwidefsky@...ibm.com" <schwidefsky@...ibm.com>,
"james.hogan@...tec.com" <james.hogan@...tec.com>,
"cmetcalf@...era.com" <cmetcalf@...era.com>,
"benh@...nel.crashing.org" <benh@...nel.crashing.org>,
"linux@....linux.org.uk" <linux@....linux.org.uk>,
"linux-arm-kernel@...ts.infradead.org"
<linux-arm-kernel@...ts.infradead.org>
CC: "linaro-kernel@...ts.linaro.org" <linaro-kernel@...ts.linaro.org>
Subject: Re: [PATCH v2 2/7] sched: rework of sched_domain topology definition
On 18/03/14 17:56, Vincent Guittot wrote:
> We replace the old way to configure the scheduler topology with a new method
> which enables a platform to declare additionnal level (if needed).
>
> We still have a default topology table definition that can be used by platform
> that don't want more level than the SMT, MC, CPU and NUMA ones. This table can
> be overwritten by an arch which wants to add new level where a load balance
> make sense like BOOK or powergating level.
>
> For each level, we need a function pointer that returns cpumask for each cpu,
> a function pointer that returns the flags for the level and a name. Only flags
> that describe topology, can be set by an architecture. The current topology
> flags are:
> SD_SHARE_CPUPOWER
> SD_SHARE_PKG_RESOURCES
> SD_NUMA
> SD_ASYM_PACKING
>
> Then, each level must be a subset on the next one. The build sequence of the
> sched_domain will take care of removing useless levels like those with 1 CPU
> and those with the same CPU span and relevant information for load balancing
> than its child.
>
> Signed-off-by: Vincent Guittot <vincent.guittot@...aro.org>
> ---
> arch/ia64/include/asm/topology.h | 24 ----
> arch/s390/include/asm/topology.h | 2 -
> arch/tile/include/asm/topology.h | 33 ------
> include/linux/sched.h | 48 ++++++++
> include/linux/topology.h | 128 +++------------------
> kernel/sched/core.c | 235 ++++++++++++++++++++-------------------
> 6 files changed, 183 insertions(+), 287 deletions(-)
>
> diff --git a/arch/ia64/include/asm/topology.h b/arch/ia64/include/asm/topology.h
> index 5cb55a1..3202aa7 100644
> --- a/arch/ia64/include/asm/topology.h
> +++ b/arch/ia64/include/asm/topology.h
> @@ -46,30 +46,6 @@
>
> void build_cpu_to_node_map(void);
>
> -#define SD_CPU_INIT (struct sched_domain) { \
> - .parent = NULL, \
> - .child = NULL, \
> - .groups = NULL, \
> - .min_interval = 1, \
> - .max_interval = 4, \
> - .busy_factor = 64, \
> - .imbalance_pct = 125, \
> - .cache_nice_tries = 2, \
> - .busy_idx = 2, \
> - .idle_idx = 1, \
> - .newidle_idx = 0, \
> - .wake_idx = 0, \
> - .forkexec_idx = 0, \
> - .flags = SD_LOAD_BALANCE \
> - | SD_BALANCE_NEWIDLE \
> - | SD_BALANCE_EXEC \
> - | SD_BALANCE_FORK \
> - | SD_WAKE_AFFINE, \
> - .last_balance = jiffies, \
> - .balance_interval = 1, \
> - .nr_balance_failed = 0, \
> -}
> -
> #endif /* CONFIG_NUMA */
>
> #ifdef CONFIG_SMP
> diff --git a/arch/s390/include/asm/topology.h b/arch/s390/include/asm/topology.h
> index 05425b1..07763bd 100644
> --- a/arch/s390/include/asm/topology.h
> +++ b/arch/s390/include/asm/topology.h
> @@ -64,8 +64,6 @@ static inline void s390_init_cpu_topology(void)
> };
> #endif
>
> -#define SD_BOOK_INIT SD_CPU_INIT
> -
> #include <asm-generic/topology.h>
>
> #endif /* _ASM_S390_TOPOLOGY_H */
> diff --git a/arch/tile/include/asm/topology.h b/arch/tile/include/asm/topology.h
> index d15c0d8..9383118 100644
> --- a/arch/tile/include/asm/topology.h
> +++ b/arch/tile/include/asm/topology.h
> @@ -44,39 +44,6 @@ static inline const struct cpumask *cpumask_of_node(int node)
> /* For now, use numa node -1 for global allocation. */
> #define pcibus_to_node(bus) ((void)(bus), -1)
>
> -/*
> - * TILE architecture has many cores integrated in one processor, so we need
> - * setup bigger balance_interval for both CPU/NODE scheduling domains to
> - * reduce process scheduling costs.
> - */
> -
> -/* sched_domains SD_CPU_INIT for TILE architecture */
> -#define SD_CPU_INIT (struct sched_domain) { \
> - .min_interval = 4, \
> - .max_interval = 128, \
> - .busy_factor = 64, \
> - .imbalance_pct = 125, \
> - .cache_nice_tries = 1, \
> - .busy_idx = 2, \
> - .idle_idx = 1, \
> - .newidle_idx = 0, \
> - .wake_idx = 0, \
> - .forkexec_idx = 0, \
> - \
> - .flags = 1*SD_LOAD_BALANCE \
> - | 1*SD_BALANCE_NEWIDLE \
> - | 1*SD_BALANCE_EXEC \
> - | 1*SD_BALANCE_FORK \
> - | 0*SD_BALANCE_WAKE \
> - | 0*SD_WAKE_AFFINE \
> - | 0*SD_SHARE_CPUPOWER \
> - | 0*SD_SHARE_PKG_RESOURCES \
> - | 0*SD_SERIALIZE \
> - , \
> - .last_balance = jiffies, \
> - .balance_interval = 32, \
> -}
> -
> /* By definition, we create nodes based on online memory. */
> #define node_has_online_mem(nid) 1
>
> diff --git a/include/linux/sched.h b/include/linux/sched.h
> index 825ed83..4db592a 100644
> --- a/include/linux/sched.h
> +++ b/include/linux/sched.h
> @@ -870,6 +870,20 @@ enum cpu_idle_type {
>
> extern int __weak arch_sd_sibiling_asym_packing(void);
>
> +#ifdef CONFIG_SCHED_SMT
> +static inline const int cpu_smt_flags(void)
> +{
> + return SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES;
> +}
> +#endif
> +
> +#ifdef CONFIG_SCHED_MC
> +static inline const int cpu_core_flags(void)
> +{
> + return SD_SHARE_PKG_RESOURCES;
> +}
> +#endif
> +
> struct sched_domain_attr {
> int relax_domain_level;
> };
> @@ -976,6 +990,38 @@ void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
>
> bool cpus_share_cache(int this_cpu, int that_cpu);
>
> +typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
> +typedef const int (*sched_domain_flags_f)(void);
> +
> +#define SDTL_OVERLAP 0x01
> +
> +struct sd_data {
> + struct sched_domain **__percpu sd;
> + struct sched_group **__percpu sg;
> + struct sched_group_power **__percpu sgp;
> +};
> +
> +struct sched_domain_topology_level {
> + sched_domain_mask_f mask;
> + sched_domain_flags_f sd_flags;
> + int flags;
> + int numa_level;
> + struct sd_data data;
> +#ifdef CONFIG_SCHED_DEBUG
> + char *name;
> +#endif
> +};
> +
> +extern struct sched_domain_topology_level *sched_domain_topology;
> +
> +extern void set_sched_topology(struct sched_domain_topology_level *tl);
> +
> +#ifdef CONFIG_SCHED_DEBUG
> +# define SD_INIT_NAME(type) .name = #type
> +#else
> +# define SD_INIT_NAME(type)
> +#endif
> +
> #else /* CONFIG_SMP */
>
> struct sched_domain_attr;
> @@ -991,6 +1037,8 @@ static inline bool cpus_share_cache(int this_cpu, int that_cpu)
> return true;
> }
>
> +static inline void set_sched_topology(struct sched_domain_topology_level *tl) { }
> +
> #endif /* !CONFIG_SMP */
>
>
> diff --git a/include/linux/topology.h b/include/linux/topology.h
> index 12ae6ce..3a9db05 100644
> --- a/include/linux/topology.h
> +++ b/include/linux/topology.h
> @@ -66,121 +66,6 @@ int arch_update_cpu_topology(void);
> #define PENALTY_FOR_NODE_WITH_CPUS (1)
> #endif
>
> -/*
> - * Below are the 3 major initializers used in building sched_domains:
> - * SD_SIBLING_INIT, for SMT domains
> - * SD_CPU_INIT, for SMP domains
> - *
> - * Any architecture that cares to do any tuning to these values should do so
> - * by defining their own arch-specific initializer in include/asm/topology.h.
> - * A definition there will automagically override these default initializers
> - * and allow arch-specific performance tuning of sched_domains.
> - * (Only non-zero and non-null fields need be specified.)
> - */
> -
> -#ifdef CONFIG_SCHED_SMT
> -/* MCD - Do we really need this? It is always on if CONFIG_SCHED_SMT is,
> - * so can't we drop this in favor of CONFIG_SCHED_SMT?
> - */
> -#define ARCH_HAS_SCHED_WAKE_IDLE
> -/* Common values for SMT siblings */
> -#ifndef SD_SIBLING_INIT
> -#define SD_SIBLING_INIT (struct sched_domain) { \
> - .min_interval = 1, \
> - .max_interval = 2, \
> - .busy_factor = 64, \
> - .imbalance_pct = 110, \
> - \
> - .flags = 1*SD_LOAD_BALANCE \
> - | 1*SD_BALANCE_NEWIDLE \
> - | 1*SD_BALANCE_EXEC \
> - | 1*SD_BALANCE_FORK \
> - | 0*SD_BALANCE_WAKE \
> - | 1*SD_WAKE_AFFINE \
> - | 1*SD_SHARE_CPUPOWER \
> - | 1*SD_SHARE_PKG_RESOURCES \
> - | 0*SD_SERIALIZE \
> - | 0*SD_PREFER_SIBLING \
> - | arch_sd_sibling_asym_packing() \
> - , \
> - .last_balance = jiffies, \
> - .balance_interval = 1, \
> - .smt_gain = 1178, /* 15% */ \
> - .max_newidle_lb_cost = 0, \
> - .next_decay_max_lb_cost = jiffies, \
> -}
> -#endif
> -#endif /* CONFIG_SCHED_SMT */
> -
> -#ifdef CONFIG_SCHED_MC
> -/* Common values for MC siblings. for now mostly derived from SD_CPU_INIT */
> -#ifndef SD_MC_INIT
> -#define SD_MC_INIT (struct sched_domain) { \
> - .min_interval = 1, \
> - .max_interval = 4, \
> - .busy_factor = 64, \
> - .imbalance_pct = 125, \
> - .cache_nice_tries = 1, \
> - .busy_idx = 2, \
> - .wake_idx = 0, \
> - .forkexec_idx = 0, \
> - \
> - .flags = 1*SD_LOAD_BALANCE \
> - | 1*SD_BALANCE_NEWIDLE \
> - | 1*SD_BALANCE_EXEC \
> - | 1*SD_BALANCE_FORK \
> - | 0*SD_BALANCE_WAKE \
> - | 1*SD_WAKE_AFFINE \
> - | 0*SD_SHARE_CPUPOWER \
> - | 1*SD_SHARE_PKG_RESOURCES \
> - | 0*SD_SERIALIZE \
> - , \
> - .last_balance = jiffies, \
> - .balance_interval = 1, \
> - .max_newidle_lb_cost = 0, \
> - .next_decay_max_lb_cost = jiffies, \
> -}
> -#endif
> -#endif /* CONFIG_SCHED_MC */
> -
> -/* Common values for CPUs */
> -#ifndef SD_CPU_INIT
> -#define SD_CPU_INIT (struct sched_domain) { \
> - .min_interval = 1, \
> - .max_interval = 4, \
> - .busy_factor = 64, \
> - .imbalance_pct = 125, \
> - .cache_nice_tries = 1, \
> - .busy_idx = 2, \
> - .idle_idx = 1, \
> - .newidle_idx = 0, \
> - .wake_idx = 0, \
> - .forkexec_idx = 0, \
> - \
> - .flags = 1*SD_LOAD_BALANCE \
> - | 1*SD_BALANCE_NEWIDLE \
> - | 1*SD_BALANCE_EXEC \
> - | 1*SD_BALANCE_FORK \
> - | 0*SD_BALANCE_WAKE \
> - | 1*SD_WAKE_AFFINE \
> - | 0*SD_SHARE_CPUPOWER \
> - | 0*SD_SHARE_PKG_RESOURCES \
> - | 0*SD_SERIALIZE \
> - | 1*SD_PREFER_SIBLING \
> - , \
> - .last_balance = jiffies, \
> - .balance_interval = 1, \
> - .max_newidle_lb_cost = 0, \
> - .next_decay_max_lb_cost = jiffies, \
> -}
> -#endif
> -
> -#ifdef CONFIG_SCHED_BOOK
> -#ifndef SD_BOOK_INIT
> -#error Please define an appropriate SD_BOOK_INIT in include/asm/topology.h!!!
> -#endif
> -#endif /* CONFIG_SCHED_BOOK */
> -
> #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
> DECLARE_PER_CPU(int, numa_node);
>
> @@ -295,4 +180,17 @@ static inline int cpu_to_mem(int cpu)
> #define topology_core_cpumask(cpu) cpumask_of(cpu)
> #endif
>
> +#ifdef CONFIG_SCHED_SMT
> +static inline const struct cpumask *cpu_smt_mask(int cpu)
> +{
> + return topology_thread_cpumask(cpu);
> +}
> +#endif
> +
> +static inline const struct cpumask *cpu_cpu_mask(int cpu)
> +{
> + return cpumask_of_node(cpu_to_node(cpu));
> +}
> +
> +
> #endif /* _LINUX_TOPOLOGY_H */
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index ae365aa..3397bcb 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -5603,17 +5603,6 @@ static int __init isolated_cpu_setup(char *str)
>
> __setup("isolcpus=", isolated_cpu_setup);
>
> -static const struct cpumask *cpu_cpu_mask(int cpu)
> -{
> - return cpumask_of_node(cpu_to_node(cpu));
> -}
> -
> -struct sd_data {
> - struct sched_domain **__percpu sd;
> - struct sched_group **__percpu sg;
> - struct sched_group_power **__percpu sgp;
> -};
> -
> struct s_data {
> struct sched_domain ** __percpu sd;
> struct root_domain *rd;
> @@ -5626,21 +5615,6 @@ enum s_alloc {
> sa_none,
> };
>
> -struct sched_domain_topology_level;
> -
> -typedef struct sched_domain *(*sched_domain_init_f)(struct sched_domain_topology_level *tl, int cpu);
> -typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
> -
> -#define SDTL_OVERLAP 0x01
> -
> -struct sched_domain_topology_level {
> - sched_domain_init_f init;
> - sched_domain_mask_f mask;
> - int flags;
> - int numa_level;
> - struct sd_data data;
> -};
> -
> /*
> * Build an iteration mask that can exclude certain CPUs from the upwards
> * domain traversal.
> @@ -5869,34 +5843,6 @@ int __weak arch_sd_sibling_asym_packing(void)
> * Non-inlined to reduce accumulated stack pressure in build_sched_domains()
> */
>
> -#ifdef CONFIG_SCHED_DEBUG
> -# define SD_INIT_NAME(sd, type) sd->name = #type
> -#else
> -# define SD_INIT_NAME(sd, type) do { } while (0)
> -#endif
> -
> -#define SD_INIT_FUNC(type) \
> -static noinline struct sched_domain * \
> -sd_init_##type(struct sched_domain_topology_level *tl, int cpu) \
> -{ \
> - struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu); \
> - *sd = SD_##type##_INIT; \
> - SD_INIT_NAME(sd, type); \
> - sd->private = &tl->data; \
> - return sd; \
> -}
> -
> -SD_INIT_FUNC(CPU)
> -#ifdef CONFIG_SCHED_SMT
> - SD_INIT_FUNC(SIBLING)
> -#endif
> -#ifdef CONFIG_SCHED_MC
> - SD_INIT_FUNC(MC)
> -#endif
> -#ifdef CONFIG_SCHED_BOOK
> - SD_INIT_FUNC(BOOK)
> -#endif
> -
> static int default_relax_domain_level = -1;
> int sched_domain_level_max;
>
> @@ -5984,97 +5930,156 @@ static void claim_allocations(int cpu, struct sched_domain *sd)
> *per_cpu_ptr(sdd->sgp, cpu) = NULL;
> }
>
> -#ifdef CONFIG_SCHED_SMT
> -static const struct cpumask *cpu_smt_mask(int cpu)
> -{
> - return topology_thread_cpumask(cpu);
> -}
> -#endif
> -
> -/*
> - * Topology list, bottom-up.
> - */
> -static struct sched_domain_topology_level default_topology[] = {
> -#ifdef CONFIG_SCHED_SMT
> - { sd_init_SIBLING, cpu_smt_mask, },
> -#endif
> -#ifdef CONFIG_SCHED_MC
> - { sd_init_MC, cpu_coregroup_mask, },
> -#endif
> -#ifdef CONFIG_SCHED_BOOK
> - { sd_init_BOOK, cpu_book_mask, },
> -#endif
> - { sd_init_CPU, cpu_cpu_mask, },
> - { NULL, },
> -};
> -
> -static struct sched_domain_topology_level *sched_domain_topology = default_topology;
> -
> -#define for_each_sd_topology(tl) \
> - for (tl = sched_domain_topology; tl->init; tl++)
> -
> #ifdef CONFIG_NUMA
> -
> static int sched_domains_numa_levels;
> static int *sched_domains_numa_distance;
> static struct cpumask ***sched_domains_numa_masks;
> static int sched_domains_curr_level;
> +#endif
>
> -static inline int sd_local_flags(int level)
> -{
> - if (sched_domains_numa_distance[level] > RECLAIM_DISTANCE)
> - return 0;
> -
> - return SD_BALANCE_EXEC | SD_BALANCE_FORK | SD_WAKE_AFFINE;
> -}
> +/*
> + * SD_flags allowed in topology descriptions.
> + *
> + * SD_SHARE_CPUPOWER - describes SMT topologies
> + * SD_SHARE_PKG_RESOURCES - describes shared caches
> + * SD_NUMA - describes NUMA topologies
> + *
> + * Odd one out:
> + * SD_ASYM_PACKING - describes SMT quirks
> + */
> +#define TOPOLOGY_SD_FLAGS \
> + (SD_SHARE_CPUPOWER | \
> + SD_SHARE_PKG_RESOURCES | \
> + SD_NUMA | \
> + SD_ASYM_PACKING)
>
> static struct sched_domain *
> -sd_numa_init(struct sched_domain_topology_level *tl, int cpu)
> +sd_init(struct sched_domain_topology_level *tl, int cpu)
> {
> struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu);
> - int level = tl->numa_level;
> - int sd_weight = cpumask_weight(
> - sched_domains_numa_masks[level][cpu_to_node(cpu)]);
> + int sd_weight, sd_flags = 0;
> +
> +#ifdef CONFIG_NUMA
> + /*
> + * Ugly hack to pass state to sd_numa_mask()...
> + */
> + sched_domains_curr_level = tl->numa_level;
> +#endif
> +
> + sd_weight = cpumask_weight(tl->mask(cpu));
> +
> + if (tl->sd_flags)
> + sd_flags = (*tl->sd_flags)();
> + if (WARN_ONCE(sd_flags & ~TOPOLOGY_SD_FLAGS,
> + "wrong sd_flags in topology description\n"))
> + sd_flags &= ~TOPOLOGY_SD_FLAGS;
>
> *sd = (struct sched_domain){
> .min_interval = sd_weight,
> .max_interval = 2*sd_weight,
> .busy_factor = 32,
> .imbalance_pct = 125,
> - .cache_nice_tries = 2,
> - .busy_idx = 3,
> - .idle_idx = 2,
> +
> + .cache_nice_tries = 0,
> + .busy_idx = 0,
> + .idle_idx = 0,
> .newidle_idx = 0,
> .wake_idx = 0,
> .forkexec_idx = 0,
>
> .flags = 1*SD_LOAD_BALANCE
> | 1*SD_BALANCE_NEWIDLE
> - | 0*SD_BALANCE_EXEC
> - | 0*SD_BALANCE_FORK
> + | 1*SD_BALANCE_EXEC
> + | 1*SD_BALANCE_FORK
> | 0*SD_BALANCE_WAKE
> - | 0*SD_WAKE_AFFINE
> + | 1*SD_WAKE_AFFINE
> | 0*SD_SHARE_CPUPOWER
> | 0*SD_SHARE_PKG_RESOURCES
> - | 1*SD_SERIALIZE
> + | 0*SD_SERIALIZE
> | 0*SD_PREFER_SIBLING
> - | 1*SD_NUMA
> - | sd_local_flags(level)
> + | 0*SD_NUMA
> + | sd_flags
> ,
> +
> .last_balance = jiffies,
> .balance_interval = sd_weight,
> + .smt_gain = 0,
> + .max_newidle_lb_cost = 0,
> + .next_decay_max_lb_cost = jiffies,
> +#ifdef CONFIG_SCHED_DEBUG
> + .name = tl->name,
> +#endif
> };
> - SD_INIT_NAME(sd, NUMA);
> - sd->private = &tl->data;
>
> /*
> - * Ugly hack to pass state to sd_numa_mask()...
> + * Convert topological properties into behaviour.
> */
> - sched_domains_curr_level = tl->numa_level;
> +
> + if (sd->flags & SD_SHARE_CPUPOWER) {
> + sd->imbalance_pct = 110;
> + sd->smt_gain = 1178; /* ~15% */
> + sd->flags |= arch_sd_sibling_asym_packing();
> +
> + } else if (sd->flags & SD_SHARE_PKG_RESOURCES) {
> + sd->imbalance_pct = 117;
> + sd->cache_nice_tries = 1;
> + sd->busy_idx = 2;
> +
> +#ifdef CONFIG_NUMA
> + } else if (sd->flags & SD_NUMA) {
> + sd->cache_nice_tries = 2;
> + sd->busy_idx = 3;
> + sd->idle_idx = 2;
> +
> + sd->flags |= SD_SERIALIZE;
> + if (sched_domains_numa_distance[tl->numa_level] > RECLAIM_DISTANCE) {
> + sd->flags &= ~(SD_BALANCE_EXEC |
> + SD_BALANCE_FORK |
> + SD_WAKE_AFFINE);
> + }
> +
> +#endif
> + } else {
> + sd->flags |= SD_PREFER_SIBLING;
> + sd->cache_nice_tries = 1;
> + sd->busy_idx = 2;
> + sd->idle_idx = 1;
> + }
This 'if ... else statement' is still a weak point from the perspective
of making the code robust:
On TC2 w/ the following change in cpu_corepower_mask()
const struct cpumask *cpu_corepower_mask(int cpu)
{
- return &cpu_topology[cpu].thread_sibling;
+ return cpu_topology[cpu].socket_id ?
&cpu_topology[cpu].thread_sibling :
+ &cpu_topology[cpu].core_sibling;
}
I get a sane set-up:
root@...aro-developer:~# cat /proc/sys/kernel/sched_domain/cpu*/domain*/name
GMC
DIE
GMC
DIE
MC
DIE
MC
DIE
MC
DIE
root@...aro-developer:~# cat
/proc/sys/kernel/sched_domain/cpu*/domain*/flags
815
4143
815
4143
559
4143
559
4143
559
4143
w/ 815 (0x32F : SD_LOAD_BALANCE SD_BALANCE_NEWIDLE SD_BALANCE_EXEC
SD_BALANCE_FORK SD_WAKE_AFFINE *SD_SHARE_POWERDOMAIN*
SD_SHARE_PKG_RESOURCES)
w/ 559 (0x22F : SD_LOAD_BALANCE SD_BALANCE_NEWIDLE SD_BALANCE_EXEC
SD_BALANCE_FORK SD_WAKE_AFFINE SD_SHARE_PKG_RESOURCES)
But when I introduce the following error into the arch specific
cpu_corepower_flags() function
static inline const int cpu_corepower_flags(void)
{
- return SD_SHARE_PKG_RESOURCES | SD_SHARE_POWERDOMAIN;
+ return SD_SHARE_POWERDOMAIN;
}
the GMC related sd's for CPU0,1 are initialized as DIE in sd_init()
resulting in this wrong set-up w/o any warning/error message:
root@...aro-developer:~# cat /proc/sys/kernel/sched_domain/cpu*/domain*/name
GMC
DIE
GMC
DIE
MC
DIE
MC
DIE
MC
DIE
root@...aro-developer:~# cat
/proc/sys/kernel/sched_domain/cpu*/domain*/flags
4399
4143
4399
4143
559
4143
559
4143
559
4143
w/ 4399 (0x112f : SD_LOAD_BALANCE SD_BALANCE_NEWIDLE SD_BALANCE_EXEC
SD_BALANCE_FORK SD_WAKE_AFFINE *SD_SHARE_POWERDOMAIN* SD_PREFER_SIBLING
Is there a way to check that MC and GMC have to have
SD_SHARE_PKG_RESOURCES set so that this can't happen unnoticed?
-- Dietmar
> +
> + sd->private = &tl->data;
>
> return sd;
> }
>
> +/*
> + * Topology list, bottom-up.
> + */
> +static struct sched_domain_topology_level default_topology[] = {
> +#ifdef CONFIG_SCHED_SMT
> + { cpu_smt_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
> +#endif
> +#ifdef CONFIG_SCHED_MC
> + { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
> +#endif
> +#ifdef CONFIG_SCHED_BOOK
> + { cpu_book_mask, SD_INIT_NAME(BOOK) },
> +#endif
> + { cpu_cpu_mask, SD_INIT_NAME(DIE) },
> + { NULL, },
> +};
> +
> +struct sched_domain_topology_level *sched_domain_topology = default_topology;
> +
> +#define for_each_sd_topology(tl) \
> + for (tl = sched_domain_topology; tl->mask; tl++)
> +
> +void set_sched_topology(struct sched_domain_topology_level *tl)
> +{
> + sched_domain_topology = tl;
> +}
> +
> +#ifdef CONFIG_NUMA
> +
> static const struct cpumask *sd_numa_mask(int cpu)
> {
> return sched_domains_numa_masks[sched_domains_curr_level][cpu_to_node(cpu)];
> @@ -6218,7 +6223,10 @@ static void sched_init_numa(void)
> }
> }
>
> - tl = kzalloc((ARRAY_SIZE(default_topology) + level) *
> + /* Compute default topology size */
> + for (i = 0; sched_domain_topology[i].mask; i++);
> +
> + tl = kzalloc((i + level) *
> sizeof(struct sched_domain_topology_level), GFP_KERNEL);
> if (!tl)
> return;
> @@ -6226,18 +6234,19 @@ static void sched_init_numa(void)
> /*
> * Copy the default topology bits..
> */
> - for (i = 0; default_topology[i].init; i++)
> - tl[i] = default_topology[i];
> + for (i = 0; sched_domain_topology[i].mask; i++)
> + tl[i] = sched_domain_topology[i];
>
> /*
> * .. and append 'j' levels of NUMA goodness.
> */
> for (j = 0; j < level; i++, j++) {
> tl[i] = (struct sched_domain_topology_level){
> - .init = sd_numa_init,
> .mask = sd_numa_mask,
> + .sd_flags = SD_NUMA,
> .flags = SDTL_OVERLAP,
> .numa_level = j,
> + SD_INIT_NAME(NUMA)
> };
> }
>
> @@ -6395,7 +6404,7 @@ struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl,
> const struct cpumask *cpu_map, struct sched_domain_attr *attr,
> struct sched_domain *child, int cpu)
> {
> - struct sched_domain *sd = tl->init(tl, cpu);
> + struct sched_domain *sd = sd_init(tl, cpu);
> if (!sd)
> return child;
>
> --
> 1.9.0
>
>
--
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