From 718dc743c8a72477ec3cad452009c48b0cf2f4ea Mon Sep 17 00:00:00 2001
From: Michal Mielewczyk <michal.mielewczyk@intel.com>
Date: Thu, 15 Oct 2020 18:19:13 -0400
Subject: [PATCH] Enable particular ioclass eviction

If partition's occupancy limit is reached, cachelines should be evicted from
 request's target partition.

Information whether particular partition eviction should be triggered is
carried as a flag by request which triggered eviction.

Signed-off-by: Michal Mielewczyk <michal.mielewczyk@intel.com>
---
 src/eviction/eviction.c | 32 +++++++++++++++++++++++++++-----
 src/ocf_request.h       | 37 +++++++++++++++++++++++++++++++++++++
 2 files changed, 64 insertions(+), 5 deletions(-)

diff --git a/src/eviction/eviction.c b/src/eviction/eviction.c
index 5a41935..bf73447 100644
--- a/src/eviction/eviction.c
+++ b/src/eviction/eviction.c
@@ -40,6 +40,22 @@ static uint32_t ocf_evict_calculate(struct ocf_user_part *part,
 	return to_evict;
 }
 
+static inline uint32_t ocf_evict_part_do(ocf_cache_t cache,
+		ocf_queue_t io_queue, const uint32_t evict_cline_no,
+		struct ocf_user_part *target_part)
+{
+	uint32_t to_evict = 0;
+
+	if (!evp_lru_can_evict(cache))
+		return 0;
+
+	to_evict = ocf_evict_calculate(&cache->user_parts[target_part_id],
+			evict_cline_no);
+
+	return ocf_eviction_need_space(cache, io_queue,
+			target_part, to_evict);
+}
+
 static inline uint32_t ocf_evict_do(ocf_cache_t cache,
 		ocf_queue_t io_queue, const uint32_t evict_cline_no,
 		struct ocf_user_part *target_part)
@@ -109,12 +125,18 @@ int space_managment_evict_do(struct ocf_cache *cache,
 	uint32_t free;
 	struct ocf_user_part *req_part = &cache->user_parts[req->part_id];
 
-	free = ocf_freelist_num_free(cache->freelist);
-	if (evict_cline_no <= free)
-		return LOOKUP_MAPPED;
+	if (ocf_req_part_evict(req)) {
+		evicted = ocf_evict_part_do(cache, req->io_queue, evict_cline_no,
+				req_part);
+	} else {
+		free = ocf_freelist_num_free(cache->freelist);
+		if (evict_cline_no <= free)
+			return LOOKUP_MAPPED;
 
-	evict_cline_no -= free;
-	evicted = ocf_evict_do(cache, req->io_queue, evict_cline_no, req_part);
+		evict_cline_no -= free;
+
+		evicted = ocf_evict_do(cache, req->io_queue, evict_cline_no, req_part);
+	}
 
 	if (evict_cline_no <= evicted)
 		return LOOKUP_MAPPED;
diff --git a/src/ocf_request.h b/src/ocf_request.h
index 2d9c7f8..21885b2 100644
--- a/src/ocf_request.h
+++ b/src/ocf_request.h
@@ -191,6 +191,9 @@ struct ocf_request {
 	uint8_t wi_second_pass : 1;
 	/*!< Set after first pass of WI write is completed */
 
+	uint8_t part_evict : 1;
+	/* !< Some cachelines from request's partition must be evicted */
+
 	log_sid_t sid;
 	/*!< Tracing sequence ID */
 
@@ -332,6 +335,40 @@ void ocf_req_clear_map(struct ocf_request *req);
  */
 void ocf_req_hash(struct ocf_request *req);
 
+/**
+ * @brief Request should trigger eviction from it's target partition
+ *
+ * @param req - OCF request
+ */
+static inline void ocf_req_set_part_evict(struct ocf_request *req)
+{
+	req->part_evict = true;
+}
+
+/**
+ * @brief Request shouldn't trigger eviction from it's target partition
+ *
+ * @param req - OCF request
+ */
+static inline void ocf_req_clear_part_evict(struct ocf_request *req)
+{
+	req->part_evict = false;
+}
+
+/**
+ * @brief Check wheter request shouldn't trigger eviction from it's target
+ *  partition or any partition
+ *
+ * @param req - OCF request
+ * @return true - Eviciton should be triggered from request's target partition
+ * @return false - Eviction should be triggered with respect to eviction
+ * priority
+ */
+static inline bool ocf_req_part_evict(struct ocf_request *req)
+{
+	return req->part_evict;
+}
+
 int ocf_req_set_dirty(struct ocf_request *req);
 
 /**