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Do not unmap inserted cachelines before eviction

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Unmapping cachelines previously mapped from freelist before
eviction is a waste of resources. Also if map does not erarly
exit upon first mapping error, we can have request fully
traversed (and partially mapped) after mapping and thus
skip lookup in eviction.

Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
This commit is contained in:
Adam Rutkowski 2021-03-05 11:20:47 +01:00
parent 81fc7ab5c5
commit 1c6168d82b
1 changed files with 26 additions and 19 deletions
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43
src/engine/engine_common.c
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@ -396,28 +396,26 @@ static void ocf_engine_map(struct ocf_request *req)
ocf_engine_lookup_map_entry(cache, entry, core_id, core_line); ocf_engine_lookup_map_entry(cache, entry, core_id, core_line);
if (entry->status != LOOKUP_HIT) { /* attempt mapping only if no mapping error previously,
ocf_engine_map_cache_line(req, i); * otherwise continue the loop anyway to have request fully
* traversed after map()
if (ocf_req_test_mapping_error(req)) {
/*
* Eviction error (mapping error), need to
* clean, return and do pass through
*/ */
OCF_DEBUG_RQ(req, "Eviction ERROR when mapping"); if (entry->status != LOOKUP_HIT &&
ocf_engine_map_hndl_error(cache, req); !ocf_req_test_mapping_error(req)) {
break; ocf_engine_map_cache_line(req, i);
} if (!ocf_req_test_mapping_error(req))
entry->status = LOOKUP_INSERTED; entry->status = LOOKUP_INSERTED;
} }
if (entry->status != LOOKUP_MISS)
ocf_engine_update_req_info(cache, req, i);
OCF_DEBUG_PARAM(req->cache, OCF_DEBUG_PARAM(req->cache,
"%s, cache line %u, core line = %llu", "%s, cache line %u, core line = %llu",
entry->status == LOOKUP_HIT ? "Hit" : "Map", entry->status == LOOKUP_HIT ? "Hit" :
entry->status == LOOKUP_MISS : "Miss" :
"Insert",
entry->coll_idx, entry->core_line); entry->coll_idx, entry->core_line);
ocf_engine_update_req_info(cache, req, i);
} }
if (!ocf_req_test_mapping_error(req)) { if (!ocf_req_test_mapping_error(req)) {
@ -493,13 +491,15 @@ static int lock_clines(struct ocf_request *req)
} }
} }
/* Attempt to map cachelines marked as LOOKUP_MISS by evicting from cache.
* Caller must assure that request map info is up to date (request
* is traversed).
*/
static inline int ocf_prepare_clines_evict(struct ocf_request *req) static inline int ocf_prepare_clines_evict(struct ocf_request *req)
{ {
int lock_status = -OCF_ERR_NO_LOCK; int lock_status = -OCF_ERR_NO_LOCK;
bool part_has_space; bool part_has_space;
ocf_engine_traverse(req);
part_has_space = ocf_part_has_space(req); part_has_space = ocf_part_has_space(req);
if (!part_has_space) { if (!part_has_space) {
/* adding more cachelines to target partition would overflow /* adding more cachelines to target partition would overflow
@ -532,8 +532,10 @@ static inline int ocf_prepare_clines_miss(struct ocf_request *req)
return lock_status; return lock_status;
} }
if (!ocf_part_has_space(req)) if (!ocf_part_has_space(req)) {
ocf_engine_traverse(req);
return ocf_prepare_clines_evict(req); return ocf_prepare_clines_evict(req);
}
ocf_engine_map(req); ocf_engine_map(req);
if (!ocf_req_test_mapping_error(req)) { if (!ocf_req_test_mapping_error(req)) {
@ -546,6 +548,11 @@ static inline int ocf_prepare_clines_miss(struct ocf_request *req)
return lock_status; return lock_status;
} }
/* Request mapping failed, but it is fully traversed as a side
* effect of ocf_engine_map(), so no need to repeat the traversation
* before eviction.
* */
req->info.mapping_error = false;
return ocf_prepare_clines_evict(req); return ocf_prepare_clines_evict(req);
} }