diff --git a/include/linux/damon.h b/include/linux/damon.h index 00baeb42c18e..076da277b249 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -253,11 +253,24 @@ struct damos { struct list_head list; }; +/** + * enum damon_ops_id - Identifier for each monitoring operations implementation + * + * @DAMON_OPS_VADDR: Monitoring operations for virtual address spaces + * @DAMON_OPS_PADDR: Monitoring operations for the physical address space + */ +enum damon_ops_id { + DAMON_OPS_VADDR, + DAMON_OPS_PADDR, + NR_DAMON_OPS, +}; + struct damon_ctx; /** * struct damon_operations - Monitoring operations for given use cases. * + * @id: Identifier of this operations set. * @init: Initialize operations-related data structures. * @update: Update operations-related data structures. * @prepare_access_checks: Prepare next access check of target regions. @@ -277,6 +290,8 @@ struct damon_ctx; * &damon_ctx.sample_interval. Finally, @reset_aggregated is called after each * &damon_ctx.aggr_interval. * + * Each &struct damon_operations instance having valid @id can be registered + * via damon_register_ops() and selected by damon_select_ops() later. * @init should initialize operations-related data structures. For example, * this could be used to construct proper monitoring target regions and link * those to @damon_ctx.adaptive_targets. @@ -301,6 +316,7 @@ struct damon_ctx; * @cleanup is called from @kdamond just before its termination. */ struct damon_operations { + enum damon_ops_id id; void (*init)(struct damon_ctx *context); void (*update)(struct damon_ctx *context); void (*prepare_access_checks)(struct damon_ctx *context); @@ -489,6 +505,8 @@ int damon_set_attrs(struct damon_ctx *ctx, unsigned long sample_int, int damon_set_schemes(struct damon_ctx *ctx, struct damos **schemes, ssize_t nr_schemes); int damon_nr_running_ctxs(void); +int damon_register_ops(struct damon_operations *ops); +int damon_select_ops(struct damon_ctx *ctx, enum damon_ops_id id); int damon_start(struct damon_ctx **ctxs, int nr_ctxs); int damon_stop(struct damon_ctx **ctxs, int nr_ctxs); diff --git a/mm/damon/core.c b/mm/damon/core.c index be93fb1c3473..82e0a4620c4f 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -25,6 +25,72 @@ static DEFINE_MUTEX(damon_lock); static int nr_running_ctxs; +static DEFINE_MUTEX(damon_ops_lock); +static struct damon_operations damon_registered_ops[NR_DAMON_OPS]; + +/* Should be called under damon_ops_lock with id smaller than NR_DAMON_OPS */ +static bool damon_registered_ops_id(enum damon_ops_id id) +{ + struct damon_operations empty_ops = {}; + + if (!memcmp(&empty_ops, &damon_registered_ops[id], sizeof(empty_ops))) + return false; + return true; +} + +/** + * damon_register_ops() - Register a monitoring operations set to DAMON. + * @ops: monitoring operations set to register. + * + * This function registers a monitoring operations set of valid &struct + * damon_operations->id so that others can find and use them later. + * + * Return: 0 on success, negative error code otherwise. + */ +int damon_register_ops(struct damon_operations *ops) +{ + int err = 0; + + if (ops->id >= NR_DAMON_OPS) + return -EINVAL; + mutex_lock(&damon_ops_lock); + /* Fail for already registered ops */ + if (damon_registered_ops_id(ops->id)) { + err = -EINVAL; + goto out; + } + damon_registered_ops[ops->id] = *ops; +out: + mutex_unlock(&damon_ops_lock); + return err; +} + +/** + * damon_select_ops() - Select a monitoring operations to use with the context. + * @ctx: monitoring context to use the operations. + * @id: id of the registered monitoring operations to select. + * + * This function finds registered monitoring operations set of @id and make + * @ctx to use it. + * + * Return: 0 on success, negative error code otherwise. + */ +int damon_select_ops(struct damon_ctx *ctx, enum damon_ops_id id) +{ + int err = 0; + + if (id >= NR_DAMON_OPS) + return -EINVAL; + + mutex_lock(&damon_ops_lock); + if (!damon_registered_ops_id(id)) + err = -EINVAL; + else + ctx->ops = damon_registered_ops[id]; + mutex_unlock(&damon_ops_lock); + return err; +} + /* * Construct a damon_region struct *