mm/damon: rename damon_primitives to damon_operations

Patch series "Allow DAMON user code independent of monitoring primitives".

In-kernel DAMON user code is required to configure the monitoring context
(struct damon_ctx) with proper monitoring primitives (struct
damon_primitive).  This makes the user code dependent to all supporting
monitoring primitives.  For example, DAMON debugfs interface depends on
both DAMON_VADDR and DAMON_PADDR, though some users have interest in only
one use case.  As more monitoring primitives are introduced, the problem
will be bigger.

To minimize such unnecessary dependency, this patchset makes monitoring
primitives can be registered by the implemnting code and later dynamically
searched and selected by the user code.

In addition to that, this patchset renames monitoring primitives to
monitoring operations, which is more easy to intuitively understand what
it means and how it would be structed.

This patch (of 8):

DAMON has a set of callback functions called monitoring primitives and let
it can be configured with various implementations for easy extension for
different address spaces and usages.  However, the word 'primitive' is not
so explicit.  Meanwhile, many other structs resembles similar purpose
calls themselves 'operations'.  To make the code easier to be understood,
this commit renames 'damon_primitives' to 'damon_operations' before it is
too late to rename.

Link: https://lkml.kernel.org/r/20220215184603.1479-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20220215184603.1479-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Xin Hao <xhao@linux.alibaba.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 33 insertions, 32 deletions

diff --git a/mm/damon/core.c b/mm/damon/core.c
index bf495236d741..be93fb1c3473 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -204,10 +204,10 @@ struct damon_ctx *damon_new_ctx(void)
 
 	ctx->sample_interval = 5 * 1000;
 	ctx->aggr_interval = 100 * 1000;
-	ctx->primitive_update_interval = 60 * 1000 * 1000;
+	ctx->ops_update_interval = 60 * 1000 * 1000;
 
 	ktime_get_coarse_ts64(&ctx->last_aggregation);
-	ctx->last_primitive_update = ctx->last_aggregation;
+	ctx->last_ops_update = ctx->last_aggregation;
 
 	mutex_init(&ctx->kdamond_lock);
 
@@ -224,8 +224,8 @@ static void damon_destroy_targets(struct damon_ctx *ctx)
 {
 	struct damon_target *t, *next_t;
 
-	if (ctx->primitive.cleanup) {
-		ctx->primitive.cleanup(ctx);
+	if (ctx->ops.cleanup) {
+		ctx->ops.cleanup(ctx);
 		return;
 	}
 
@@ -250,7 +250,7 @@ void damon_destroy_ctx(struct damon_ctx *ctx)
  * @ctx:		monitoring context
  * @sample_int:		time interval between samplings
  * @aggr_int:		time interval between aggregations
- * @primitive_upd_int:	time interval between monitoring primitive updates
+ * @ops_upd_int:	time interval between monitoring operations updates
  * @min_nr_reg:		minimal number of regions
  * @max_nr_reg:		maximum number of regions
  *
@@ -260,7 +260,7 @@ void damon_destroy_ctx(struct damon_ctx *ctx)
  * Return: 0 on success, negative error code otherwise.
  */
 int damon_set_attrs(struct damon_ctx *ctx, unsigned long sample_int,
-		    unsigned long aggr_int, unsigned long primitive_upd_int,
+		    unsigned long aggr_int, unsigned long ops_upd_int,
 		    unsigned long min_nr_reg, unsigned long max_nr_reg)
 {
 	if (min_nr_reg < 3)
@@ -270,7 +270,7 @@ int damon_set_attrs(struct damon_ctx *ctx, unsigned long sample_int,
 
 	ctx->sample_interval = sample_int;
 	ctx->aggr_interval = aggr_int;
-	ctx->primitive_update_interval = primitive_upd_int;
+	ctx->ops_update_interval = ops_upd_int;
 	ctx->min_nr_regions = min_nr_reg;
 	ctx->max_nr_regions = max_nr_reg;
 
@@ -516,10 +516,10 @@ static bool damos_valid_target(struct damon_ctx *c, struct damon_target *t,
 {
 	bool ret = __damos_valid_target(r, s);
 
-	if (!ret || !s->quota.esz || !c->primitive.get_scheme_score)
+	if (!ret || !s->quota.esz || !c->ops.get_scheme_score)
 		return ret;
 
-	return c->primitive.get_scheme_score(c, t, r, s) >= s->quota.min_score;
+	return c->ops.get_scheme_score(c, t, r, s) >= s->quota.min_score;
 }
 
 static void damon_do_apply_schemes(struct damon_ctx *c,
@@ -576,7 +576,7 @@ static void damon_do_apply_schemes(struct damon_ctx *c,
 			continue;
 
 		/* Apply the scheme */
-		if (c->primitive.apply_scheme) {
+		if (c->ops.apply_scheme) {
 			if (quota->esz &&
 					quota->charged_sz + sz > quota->esz) {
 				sz = ALIGN_DOWN(quota->esz - quota->charged_sz,
@@ -586,7 +586,7 @@ static void damon_do_apply_schemes(struct damon_ctx *c,
 				damon_split_region_at(c, t, r, sz);
 			}
 			ktime_get_coarse_ts64(&begin);
-			sz_applied = c->primitive.apply_scheme(c, t, r, s);
+			sz_applied = c->ops.apply_scheme(c, t, r, s);
 			ktime_get_coarse_ts64(&end);
 			quota->total_charged_ns += timespec64_to_ns(&end) -
 				timespec64_to_ns(&begin);
@@ -660,7 +660,7 @@ static void kdamond_apply_schemes(struct damon_ctx *c)
 			damos_set_effective_quota(quota);
 		}
 
-		if (!c->primitive.get_scheme_score)
+		if (!c->ops.get_scheme_score)
 			continue;
 
 		/* Fill up the score histogram */
@@ -669,7 +669,7 @@ static void kdamond_apply_schemes(struct damon_ctx *c)
 			damon_for_each_region(r, t) {
 				if (!__damos_valid_target(r, s))
 					continue;
-				score = c->primitive.get_scheme_score(
+				score = c->ops.get_scheme_score(
 						c, t, r, s);
 				quota->histogram[score] +=
 					r->ar.end - r->ar.start;
@@ -848,14 +848,15 @@ static void kdamond_split_regions(struct damon_ctx *ctx)
 }
 
 /*
- * Check whether it is time to check and apply the target monitoring regions
+ * Check whether it is time to check and apply the operations-related data
+ * structures.
  *
  * Returns true if it is.
  */
-static bool kdamond_need_update_primitive(struct damon_ctx *ctx)
+static bool kdamond_need_update_operations(struct damon_ctx *ctx)
 {
-	return damon_check_reset_time_interval(&ctx->last_primitive_update,
-			ctx->primitive_update_interval);
+	return damon_check_reset_time_interval(&ctx->last_ops_update,
+			ctx->ops_update_interval);
 }
 
 /*
@@ -873,11 +874,11 @@ static bool kdamond_need_stop(struct damon_ctx *ctx)
 	if (kthread_should_stop())
 		return true;
 
-	if (!ctx->primitive.target_valid)
+	if (!ctx->ops.target_valid)
 		return false;
 
 	damon_for_each_target(t, ctx) {
-		if (ctx->primitive.target_valid(t))
+		if (ctx->ops.target_valid(t))
 			return false;
 	}
 
@@ -976,8 +977,8 @@ static int kdamond_fn(void *data)
 
 	pr_debug("kdamond (%d) starts\n", current->pid);
 
-	if (ctx->primitive.init)
-		ctx->primitive.init(ctx);
+	if (ctx->ops.init)
+		ctx->ops.init(ctx);
 	if (ctx->callback.before_start && ctx->callback.before_start(ctx))
 		done = true;
 
@@ -987,16 +988,16 @@ static int kdamond_fn(void *data)
 		if (kdamond_wait_activation(ctx))
 			continue;
 
-		if (ctx->primitive.prepare_access_checks)
-			ctx->primitive.prepare_access_checks(ctx);
+		if (ctx->ops.prepare_access_checks)
+			ctx->ops.prepare_access_checks(ctx);
 		if (ctx->callback.after_sampling &&
 				ctx->callback.after_sampling(ctx))
 			done = true;
 
 		kdamond_usleep(ctx->sample_interval);
 
-		if (ctx->primitive.check_accesses)
-			max_nr_accesses = ctx->primitive.check_accesses(ctx);
+		if (ctx->ops.check_accesses)
+			max_nr_accesses = ctx->ops.check_accesses(ctx);
 
 		if (kdamond_aggregate_interval_passed(ctx)) {
 			kdamond_merge_regions(ctx,
@@ -1008,13 +1009,13 @@ static int kdamond_fn(void *data)
 			kdamond_apply_schemes(ctx);
 			kdamond_reset_aggregated(ctx);
 			kdamond_split_regions(ctx);
-			if (ctx->primitive.reset_aggregated)
-				ctx->primitive.reset_aggregated(ctx);
+			if (ctx->ops.reset_aggregated)
+				ctx->ops.reset_aggregated(ctx);
 		}
 
-		if (kdamond_need_update_primitive(ctx)) {
-			if (ctx->primitive.update)
-				ctx->primitive.update(ctx);
+		if (kdamond_need_update_operations(ctx)) {
+			if (ctx->ops.update)
+				ctx->ops.update(ctx);
 			sz_limit = damon_region_sz_limit(ctx);
 		}
 	}
@@ -1025,8 +1026,8 @@ static int kdamond_fn(void *data)
 
 	if (ctx->callback.before_terminate)
 		ctx->callback.before_terminate(ctx);
-	if (ctx->primitive.cleanup)
-		ctx->primitive.cleanup(ctx);
+	if (ctx->ops.cleanup)
+		ctx->ops.cleanup(ctx);
 
 	pr_debug("kdamond (%d) finishes\n", current->pid);
 	mutex_lock(&ctx->kdamond_lock);