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Optimize set_hot calls in eviction path

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Split traversation into two distinct phases: lookup()
and lru set_hot(). prepare_cachelines() now only calls
set_hot() once after lookup and insert are finished.
lookup() is called explicitly only once in
prepare_cachelines() at the very beginning of the
procedure. If request is a miss then then map()
performs operations equivalent to lookup() supplemented
by an attempt to map cachelines. Both lookup() and
set_hot() are called via traverse() from the engines
which do not attempt mapping, and thus do not call
prepare_clines().

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 1c6168d82b
commit 7927b0b74f
2 changed files with 37 additions and 10 deletions
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8
src/concurrency/ocf_metadata_concurrency.c
View File

@ -423,7 +423,12 @@ void ocf_hb_id_prot_unlock_wr(struct ocf_metadata_lock *metadata_lock,
for (hash = _MIN_HASH(req); hash <= _MAX_HASH(req); \
hash = _HASH_NEXT(req, hash))
/* returns true if given core hash collides with request LBA range */
/* Returns true if the the given LBA (determined by core_id
* and core_line) resolves to a hash value that is within the
* set of hashes for the given request (i.e. after the request
* hash bucket are locked, the given core line is hash bucket
* locked as well).
*/
bool ocf_req_hash_in_range(struct ocf_request *req,
ocf_core_id_t core_id, uint64_t core_line)
{
@ -438,7 +443,6 @@ bool ocf_req_hash_in_range(struct ocf_request *req,
return (hash >= _MIN_HASH(req) && hash <= _GAP_START(req)) ||
(hash > _GAP_START(req) + _GAP_VAL(req) &&
hash <= _MAX_HASH(req));
}
void ocf_hb_req_prot_lock_rd(struct ocf_request *req)

39
src/engine/engine_common.c
View File

@ -196,7 +196,25 @@ static void ocf_engine_update_req_info(struct ocf_cache *cache,
req->info.seq_no++;
}
void ocf_engine_traverse(struct ocf_request *req)
static void ocf_engine_set_hot(struct ocf_request *req)
{
struct ocf_cache *cache = req->cache;
struct ocf_map_info *entry;
uint8_t status;
unsigned i;
for (i = 0; i < req->core_line_count; i++) {
entry = &(req->map[i]);
status = entry->status;
if (status == LOOKUP_HIT || status == LOOKUP_INSERTED) {
/* Update eviction (LRU) */
ocf_eviction_set_hot_cache_line(cache, entry->coll_idx);
}
}
}
static void ocf_engine_lookup(struct ocf_request *req)
{
uint32_t i;
uint64_t core_line;
@ -226,15 +244,17 @@ void ocf_engine_traverse(struct ocf_request *req)
OCF_DEBUG_PARAM(cache, "Hit, cache line %u, core line = %llu",
entry->coll_idx, entry->core_line);
/* Update eviction (LRU) */
ocf_eviction_set_hot_cache_line(cache, entry->coll_idx);
ocf_engine_update_req_info(cache, req, i);
}
OCF_DEBUG_PARAM(cache, "Sequential - %s", ocf_engine_is_sequential(req)
? "Yes" : "No");
}
void ocf_engine_traverse(struct ocf_request *req)
{
ocf_engine_lookup(req);
ocf_engine_set_hot(req);
}
int ocf_engine_check(struct ocf_request *req)
{
@ -327,7 +347,6 @@ static void ocf_engine_map_cache_line(struct ocf_request *req,
/* Update LRU:: Move this node to head of lru list. */
ocf_eviction_init_cache_line(cache, cache_line);
ocf_eviction_set_hot_cache_line(cache, cache_line);
}
static void ocf_engine_map_hndl_error(struct ocf_cache *cache,
@ -533,7 +552,7 @@ static inline int ocf_prepare_clines_miss(struct ocf_request *req)
}
if (!ocf_part_has_space(req)) {
ocf_engine_traverse(req);
ocf_engine_lookup(req);
return ocf_prepare_clines_evict(req);
}
@ -572,13 +591,14 @@ int ocf_engine_prepare_clines(struct ocf_request *req)
* not change during traversation */
ocf_hb_req_prot_lock_rd(req);
/* Traverse to check if request is mapped fully */
ocf_engine_traverse(req);
/* check CL status */
ocf_engine_lookup(req);
mapped = ocf_engine_is_mapped(req);
if (mapped) {
lock = lock_clines(req);
ocf_hb_req_prot_unlock_rd(req);
ocf_engine_set_hot(req);
return lock;
}
@ -601,6 +621,9 @@ int ocf_engine_prepare_clines(struct ocf_request *req)
128);
}
if (!ocf_req_test_mapping_error(req))
ocf_engine_set_hot(req);
return result;
}