diff options
| -rw-r--r-- | include/linux/damon.h | 26 | ||||
| -rw-r--r-- | mm/damon/core.c | 62 |
2 files changed, 81 insertions, 7 deletions
diff --git a/include/linux/damon.h b/include/linux/damon.h index 1e7671bf3d23..5d47ad9e3911 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -14,6 +14,8 @@ /* Minimal region size. Every damon_region is aligned by this. */ #define DAMON_MIN_REGION PAGE_SIZE +/* Max priority score for DAMON-based operation schemes */ +#define DAMOS_MAX_SCORE (99) /** * struct damon_addr_range - Represents an address region of [@start, @end). @@ -95,6 +97,10 @@ enum damos_action { * @sz: Maximum bytes of memory that the action can be applied. * @reset_interval: Charge reset interval in milliseconds. * + * @weight_sz: Weight of the region's size for prioritization. + * @weight_nr_accesses: Weight of the region's nr_accesses for prioritization. + * @weight_age: Weight of the region's age for prioritization. + * * To avoid consuming too much CPU time or IO resources for applying the * &struct damos->action to large memory, DAMON allows users to set time and/or * size quotas. The quotas can be set by writing non-zero values to &ms and @@ -106,12 +112,22 @@ enum damos_action { * Internally, the time quota is transformed to a size quota using estimated * throughput of the scheme's action. DAMON then compares it against &sz and * uses smaller one as the effective quota. + * + * For selecting regions within the quota, DAMON prioritizes current scheme's + * target memory regions using the &struct damon_primitive->get_scheme_score. + * You could customize the prioritization logic by setting &weight_sz, + * &weight_nr_accesses, and &weight_age, because monitoring primitives are + * encouraged to respect those. */ struct damos_quota { unsigned long ms; unsigned long sz; unsigned long reset_interval; + unsigned int weight_sz; + unsigned int weight_nr_accesses; + unsigned int weight_age; + /* private: */ /* For throughput estimation */ unsigned long total_charged_sz; @@ -124,6 +140,10 @@ struct damos_quota { unsigned long charged_from; struct damon_target *charge_target_from; unsigned long charge_addr_from; + + /* For prioritization */ + unsigned long histogram[DAMOS_MAX_SCORE + 1]; + unsigned int min_score; }; /** @@ -174,6 +194,7 @@ struct damon_ctx; * @prepare_access_checks: Prepare next access check of target regions. * @check_accesses: Check the accesses to target regions. * @reset_aggregated: Reset aggregated accesses monitoring results. + * @get_scheme_score: Get the score of a region for a scheme. * @apply_scheme: Apply a DAMON-based operation scheme. * @target_valid: Determine if the target is valid. * @cleanup: Clean up the context. @@ -200,6 +221,8 @@ struct damon_ctx; * of its update. The value will be used for regions adjustment threshold. * @reset_aggregated should reset the access monitoring results that aggregated * by @check_accesses. + * @get_scheme_score should return the priority score of a region for a scheme + * as an integer in [0, &DAMOS_MAX_SCORE]. * @apply_scheme is called from @kdamond when a region for user provided * DAMON-based operation scheme is found. It should apply the scheme's action * to the region. This is not used for &DAMON_ARBITRARY_TARGET case. @@ -213,6 +236,9 @@ struct damon_primitive { void (*prepare_access_checks)(struct damon_ctx *context); unsigned int (*check_accesses)(struct damon_ctx *context); void (*reset_aggregated)(struct damon_ctx *context); + int (*get_scheme_score)(struct damon_ctx *context, + struct damon_target *t, struct damon_region *r, + struct damos *scheme); int (*apply_scheme)(struct damon_ctx *context, struct damon_target *t, struct damon_region *r, struct damos *scheme); bool (*target_valid)(void *target); diff --git a/mm/damon/core.c b/mm/damon/core.c index d1da4bef96ed..fad25778e2ec 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -12,6 +12,7 @@ #include <linux/kthread.h> #include <linux/random.h> #include <linux/slab.h> +#include <linux/string.h> #define CREATE_TRACE_POINTS #include <trace/events/damon.h> @@ -110,6 +111,9 @@ struct damos *damon_new_scheme( scheme->quota.ms = quota->ms; scheme->quota.sz = quota->sz; scheme->quota.reset_interval = quota->reset_interval; + scheme->quota.weight_sz = quota->weight_sz; + scheme->quota.weight_nr_accesses = quota->weight_nr_accesses; + scheme->quota.weight_age = quota->weight_age; scheme->quota.total_charged_sz = 0; scheme->quota.total_charged_ns = 0; scheme->quota.esz = 0; @@ -545,6 +549,28 @@ static void damon_split_region_at(struct damon_ctx *ctx, struct damon_target *t, struct damon_region *r, unsigned long sz_r); +static bool __damos_valid_target(struct damon_region *r, struct damos *s) +{ + unsigned long sz; + + sz = r->ar.end - r->ar.start; + return s->min_sz_region <= sz && sz <= s->max_sz_region && + s->min_nr_accesses <= r->nr_accesses && + r->nr_accesses <= s->max_nr_accesses && + s->min_age_region <= r->age && r->age <= s->max_age_region; +} + +static bool damos_valid_target(struct damon_ctx *c, struct damon_target *t, + struct damon_region *r, struct damos *s) +{ + bool ret = __damos_valid_target(r, s); + + if (!ret || !s->quota.esz || !c->primitive.get_scheme_score) + return ret; + + return c->primitive.get_scheme_score(c, t, r, s) >= s->quota.min_score; +} + static void damon_do_apply_schemes(struct damon_ctx *c, struct damon_target *t, struct damon_region *r) @@ -591,13 +617,7 @@ static void damon_do_apply_schemes(struct damon_ctx *c, quota->charge_addr_from = 0; } - /* Check the target regions condition */ - if (sz < s->min_sz_region || s->max_sz_region < sz) - continue; - if (r->nr_accesses < s->min_nr_accesses || - s->max_nr_accesses < r->nr_accesses) - continue; - if (r->age < s->min_age_region || s->max_age_region < r->age) + if (!damos_valid_target(c, t, r, s)) continue; /* Apply the scheme */ @@ -661,6 +681,8 @@ static void kdamond_apply_schemes(struct damon_ctx *c) damon_for_each_scheme(s, c) { struct damos_quota *quota = &s->quota; + unsigned long cumulated_sz; + unsigned int score, max_score = 0; if (!quota->ms && !quota->sz) continue; @@ -674,6 +696,32 @@ static void kdamond_apply_schemes(struct damon_ctx *c) quota->charged_sz = 0; damos_set_effective_quota(quota); } + + if (!c->primitive.get_scheme_score) + continue; + + /* Fill up the score histogram */ + memset(quota->histogram, 0, sizeof(quota->histogram)); + damon_for_each_target(t, c) { + damon_for_each_region(r, t) { + if (!__damos_valid_target(r, s)) + continue; + score = c->primitive.get_scheme_score( + c, t, r, s); + quota->histogram[score] += + r->ar.end - r->ar.start; + if (score > max_score) + max_score = score; + } + } + + /* Set the min score limit */ + for (cumulated_sz = 0, score = max_score; ; score--) { + cumulated_sz += quota->histogram[score]; + if (cumulated_sz >= quota->esz || !score) + break; + } + quota->min_score = score; } damon_for_each_target(t, c) { |