diff options
Diffstat (limited to 'include/linux/damon.h')
-rw-r--r-- | include/linux/damon.h | 133 |
1 files changed, 117 insertions, 16 deletions
diff --git a/include/linux/damon.h b/include/linux/damon.h index 343132a146cf..a67f2c4940e9 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -2,7 +2,7 @@ /* * DAMON api * - * Author: SeongJae Park <sjpark@amazon.de> + * Author: SeongJae Park <sj@kernel.org> */ #ifndef _DAMON_H_ @@ -40,9 +40,24 @@ struct damon_addr_range { * @ar: The address range of the region. * @sampling_addr: Address of the sample for the next access check. * @nr_accesses: Access frequency of this region. + * @nr_accesses_bp: @nr_accesses in basis point (0.01%) that updated for + * each sampling interval. * @list: List head for siblings. * @age: Age of this region. * + * @nr_accesses is reset to zero for every &damon_attrs->aggr_interval and be + * increased for every &damon_attrs->sample_interval if an access to the region + * during the last sampling interval is found. The update of this field should + * not be done with direct access but with the helper function, + * damon_update_region_access_rate(). + * + * @nr_accesses_bp is another representation of @nr_accesses in basis point + * (1 in 10,000) that updated for every &damon_attrs->sample_interval in a + * manner similar to moving sum. By the algorithm, this value becomes + * @nr_accesses * 10000 for every &struct damon_attrs->aggr_interval. This can + * be used when the aggregation interval is too huge and therefore cannot wait + * for it before getting the access monitoring results. + * * @age is initially zero, increased for each aggregation interval, and reset * to zero again if the access frequency is significantly changed. If two * regions are merged into a new region, both @nr_accesses and @age of the new @@ -52,6 +67,7 @@ struct damon_region { struct damon_addr_range ar; unsigned long sampling_addr; unsigned int nr_accesses; + unsigned int nr_accesses_bp; struct list_head list; unsigned int age; @@ -89,6 +105,8 @@ struct damon_target { * @DAMOS_NOHUGEPAGE: Call ``madvise()`` for the region with MADV_NOHUGEPAGE. * @DAMOS_LRU_PRIO: Prioritize the region on its LRU lists. * @DAMOS_LRU_DEPRIO: Deprioritize the region on its LRU lists. + * @DAMOS_MIGRATE_HOT: Migrate the regions prioritizing warmer regions. + * @DAMOS_MIGRATE_COLD: Migrate the regions prioritizing colder regions. * @DAMOS_STAT: Do nothing but count the stat. * @NR_DAMOS_ACTIONS: Total number of DAMOS actions * @@ -106,15 +124,62 @@ enum damos_action { DAMOS_NOHUGEPAGE, DAMOS_LRU_PRIO, DAMOS_LRU_DEPRIO, + DAMOS_MIGRATE_HOT, + DAMOS_MIGRATE_COLD, DAMOS_STAT, /* Do nothing but only record the stat */ NR_DAMOS_ACTIONS, }; /** + * enum damos_quota_goal_metric - Represents the metric to be used as the goal + * + * @DAMOS_QUOTA_USER_INPUT: User-input value. + * @DAMOS_QUOTA_SOME_MEM_PSI_US: System level some memory PSI in us. + * @NR_DAMOS_QUOTA_GOAL_METRICS: Number of DAMOS quota goal metrics. + * + * Metrics equal to larger than @NR_DAMOS_QUOTA_GOAL_METRICS are unsupported. + */ +enum damos_quota_goal_metric { + DAMOS_QUOTA_USER_INPUT, + DAMOS_QUOTA_SOME_MEM_PSI_US, + NR_DAMOS_QUOTA_GOAL_METRICS, +}; + +/** + * struct damos_quota_goal - DAMOS scheme quota auto-tuning goal. + * @metric: Metric to be used for representing the goal. + * @target_value: Target value of @metric to achieve with the tuning. + * @current_value: Current value of @metric. + * @last_psi_total: Last measured total PSI + * @list: List head for siblings. + * + * Data structure for getting the current score of the quota tuning goal. The + * score is calculated by how close @current_value and @target_value are. Then + * the score is entered to DAMON's internal feedback loop mechanism to get the + * auto-tuned quota. + * + * If @metric is DAMOS_QUOTA_USER_INPUT, @current_value should be manually + * entered by the user, probably inside the kdamond callbacks. Otherwise, + * DAMON sets @current_value with self-measured value of @metric. + */ +struct damos_quota_goal { + enum damos_quota_goal_metric metric; + unsigned long target_value; + unsigned long current_value; + /* metric-dependent fields */ + union { + u64 last_psi_total; + }; + struct list_head list; +}; + +/** * struct damos_quota - Controls the aggressiveness of the given scheme. + * @reset_interval: Charge reset interval in milliseconds. * @ms: Maximum milliseconds that the scheme can use. * @sz: Maximum bytes of memory that the action can be applied. - * @reset_interval: Charge reset interval in milliseconds. + * @goals: Head of quota tuning goals (&damos_quota_goal) list. + * @esz: Effective size quota in bytes. * * @weight_sz: Weight of the region's size for prioritization. * @weight_nr_accesses: Weight of the region's nr_accesses for prioritization. @@ -132,6 +197,13 @@ enum damos_action { * throughput of the scheme's action. DAMON then compares it against &sz and * uses smaller one as the effective quota. * + * If @goals is not empt, DAMON calculates yet another size quota based on the + * goals using its internal feedback loop algorithm, for every @reset_interval. + * Then, if the new size quota is smaller than the effective quota, it uses the + * new size quota as the effective quota. + * + * The resulting effective size quota in bytes is set to @esz. + * * For selecting regions within the quota, DAMON prioritizes current scheme's * target memory regions using the &struct damon_operations->get_scheme_score. * You could customize the prioritization logic by setting &weight_sz, @@ -139,9 +211,11 @@ enum damos_action { * encouraged to respect those. */ struct damos_quota { + unsigned long reset_interval; unsigned long ms; unsigned long sz; - unsigned long reset_interval; + struct list_head goals; + unsigned long esz; unsigned int weight_sz; unsigned int weight_nr_accesses; @@ -152,8 +226,6 @@ struct damos_quota { unsigned long total_charged_sz; unsigned long total_charged_ns; - unsigned long esz; /* Effective size quota in bytes */ - /* For charging the quota */ unsigned long charged_sz; unsigned long charged_from; @@ -161,8 +233,10 @@ struct damos_quota { unsigned long charge_addr_from; /* For prioritization */ - unsigned long histogram[DAMOS_MAX_SCORE + 1]; unsigned int min_score; + + /* For feedback loop */ + unsigned long esz_bp; }; /** @@ -226,6 +300,7 @@ struct damos_stat { * enum damos_filter_type - Type of memory for &struct damos_filter * @DAMOS_FILTER_TYPE_ANON: Anonymous pages. * @DAMOS_FILTER_TYPE_MEMCG: Specific memcg's pages. + * @DAMOS_FILTER_TYPE_YOUNG: Recently accessed pages. * @DAMOS_FILTER_TYPE_ADDR: Address range. * @DAMOS_FILTER_TYPE_TARGET: Data Access Monitoring target. * @NR_DAMOS_FILTER_TYPES: Number of filter types. @@ -244,6 +319,7 @@ struct damos_stat { enum damos_filter_type { DAMOS_FILTER_TYPE_ANON, DAMOS_FILTER_TYPE_MEMCG, + DAMOS_FILTER_TYPE_YOUNG, DAMOS_FILTER_TYPE_ADDR, DAMOS_FILTER_TYPE_TARGET, NR_DAMOS_FILTER_TYPES, @@ -301,6 +377,7 @@ struct damos_access_pattern { * @apply_interval_us: The time between applying the @action. * @quota: Control the aggressiveness of this scheme. * @wmarks: Watermarks for automated (in)activation of this scheme. + * @target_nid: Destination node if @action is "migrate_{hot,cold}". * @filters: Additional set of &struct damos_filter for &action. * @stat: Statistics of this scheme. * @list: List head for siblings. @@ -316,8 +393,9 @@ struct damos_access_pattern { * monitoring context are inactive, DAMON stops monitoring either, and just * repeatedly checks the watermarks. * - * If all schemes that registered to a &struct damon_ctx are inactive, DAMON - * stops monitoring and just repeatedly checks the watermarks. + * @target_nid is used to set the migration target node for migrate_hot or + * migrate_cold actions, which means it's only meaningful when @action is either + * "migrate_hot" or "migrate_cold". * * Before applying the &action to a memory region, &struct damon_operations * implementation could check pages of the region and skip &action to respect @@ -340,6 +418,9 @@ struct damos { /* public: */ struct damos_quota quota; struct damos_watermarks wmarks; + union { + int target_nid; + }; struct list_head filters; struct damos_stat stat; struct list_head list; @@ -483,13 +564,14 @@ struct damon_callback { * regions. * * For each @sample_interval, DAMON checks whether each region is accessed or - * not. It aggregates and keeps the access information (number of accesses to - * each region) for @aggr_interval time. DAMON also checks whether the target - * memory regions need update (e.g., by ``mmap()`` calls from the application, - * in case of virtual memory monitoring) and applies the changes for each - * @ops_update_interval. All time intervals are in micro-seconds. - * Please refer to &struct damon_operations and &struct damon_callback for more - * detail. + * not during the last @sample_interval. If such access is found, DAMON + * aggregates the information by increasing &damon_region->nr_accesses for + * @aggr_interval time. For each @aggr_interval, the count is reset. DAMON + * also checks whether the target memory regions need update (e.g., by + * ``mmap()`` calls from the application, in case of virtual memory monitoring) + * and applies the changes for each @ops_update_interval. All time intervals + * are in micro-seconds. Please refer to &struct damon_operations and &struct + * damon_callback for more detail. */ struct damon_attrs { unsigned long sample_interval; @@ -547,6 +629,8 @@ struct damon_ctx { unsigned long next_ops_update_sis; /* for waiting until the execution of the kdamond_fn is started */ struct completion kdamond_started; + /* for scheme quotas prioritization */ + unsigned long *regions_score_histogram; /* public: */ struct task_struct *kdamond; @@ -606,6 +690,12 @@ static inline unsigned long damon_sz_region(struct damon_region *r) #define damon_for_each_scheme_safe(s, next, ctx) \ list_for_each_entry_safe(s, next, &(ctx)->schemes, list) +#define damos_for_each_quota_goal(goal, quota) \ + list_for_each_entry(goal, "a->goals, list) + +#define damos_for_each_quota_goal_safe(goal, next, quota) \ + list_for_each_entry_safe(goal, next, &(quota)->goals, list) + #define damos_for_each_filter(f, scheme) \ list_for_each_entry(f, &(scheme)->filters, list) @@ -631,19 +721,29 @@ void damon_add_region(struct damon_region *r, struct damon_target *t); void damon_destroy_region(struct damon_region *r, struct damon_target *t); int damon_set_regions(struct damon_target *t, struct damon_addr_range *ranges, unsigned int nr_ranges); +void damon_update_region_access_rate(struct damon_region *r, bool accessed, + struct damon_attrs *attrs); struct damos_filter *damos_new_filter(enum damos_filter_type type, bool matching); void damos_add_filter(struct damos *s, struct damos_filter *f); void damos_destroy_filter(struct damos_filter *f); +struct damos_quota_goal *damos_new_quota_goal( + enum damos_quota_goal_metric metric, + unsigned long target_value); +void damos_add_quota_goal(struct damos_quota *q, struct damos_quota_goal *g); +void damos_destroy_quota_goal(struct damos_quota_goal *goal); + struct damos *damon_new_scheme(struct damos_access_pattern *pattern, enum damos_action action, unsigned long apply_interval_us, struct damos_quota *quota, - struct damos_watermarks *wmarks); + struct damos_watermarks *wmarks, + int target_nid); void damon_add_scheme(struct damon_ctx *ctx, struct damos *s); void damon_destroy_scheme(struct damos *s); +int damos_commit_quota_goals(struct damos_quota *dst, struct damos_quota *src); struct damon_target *damon_new_target(void); void damon_add_target(struct damon_ctx *ctx, struct damon_target *t); @@ -657,6 +757,7 @@ void damon_destroy_ctx(struct damon_ctx *ctx); int damon_set_attrs(struct damon_ctx *ctx, struct damon_attrs *attrs); void damon_set_schemes(struct damon_ctx *ctx, struct damos **schemes, ssize_t nr_schemes); +int damon_commit_ctx(struct damon_ctx *old_ctx, struct damon_ctx *new_ctx); int damon_nr_running_ctxs(void); bool damon_is_registered_ops(enum damon_ops_id id); int damon_register_ops(struct damon_operations *ops); |