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[kvdb] Speed up find by header name_crc gate #380

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[kvdb] Speed up find by header name_crc gate #380

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2 changes: 1 addition & 1 deletion inc/fdb_def.h
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Original file line number Diff line number Diff line change
Expand Up @@ -162,6 +162,7 @@ struct fdb_kv {
fdb_kv_status_t status; /**< node status, @see fdb_kv_status_t */
bool crc_is_ok; /**< node CRC32 check is OK */
uint8_t name_len; /**< name length */
uint16_t name_crc; /**< KV name's CRC32 low 16bit value (optional fast match) */
uint32_t magic; /**< magic word(`K`, `V`, `4`, `0`) */
uint32_t len; /**< node total length (header + name + value), must align by FDB_WRITE_GRAN */
uint32_t value_len; /**< value length */
Expand Down Expand Up @@ -348,4 +349,3 @@ typedef struct fdb_blob *fdb_blob_t;
#endif

#endif /* _FDB_DEF_H_ */

64 changes: 46 additions & 18 deletions src/fdb_kvdb.c
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Original file line number Diff line number Diff line change
Expand Up @@ -12,6 +12,7 @@
*/

#include <inttypes.h>
#include <stdint.h>
#include <string.h>
#include <flashdb.h>
#include <fdb_low_lvl.h>
Expand Down Expand Up @@ -119,6 +120,7 @@ struct kv_hdr_data {
uint32_t len; /**< KV node total length (header + name + value), must align by FDB_WRITE_GRAN */
uint32_t crc32; /**< KV node crc32(name_len + data_len + name + value) */
uint8_t name_len; /**< name length */
uint16_t name_crc;
uint32_t value_len; /**< value length */
#if (FDB_WRITE_GRAN == 64)
uint8_t padding[4]; /**< align padding for 64bit write granularity */
Expand Down Expand Up @@ -342,7 +344,13 @@ static uint32_t get_next_kv_addr(fdb_kvdb_t db, kv_sec_info_t sector, fdb_kv_t p
return addr;
}

static fdb_err_t read_kv(fdb_kvdb_t db, fdb_kv_t kv)
struct kv_search_ctx {
const char *key;
size_t key_len;
uint16_t name_crc;
};

static fdb_err_t read_kv(fdb_kvdb_t db, fdb_kv_t kv, const struct kv_search_ctx *search_ctx)
{
struct kv_hdr_data kv_hdr;
uint8_t buf[32];
Expand All @@ -353,6 +361,9 @@ static fdb_err_t read_kv(fdb_kvdb_t db, fdb_kv_t kv)
_fdb_flash_read((fdb_db_t)db, kv->addr.start, (uint32_t *)&kv_hdr, sizeof(struct kv_hdr_data));
kv->status = (fdb_kv_status_t) _fdb_get_status(kv_hdr.status_table, FDB_KV_STATUS_NUM);
kv->len = kv_hdr.len;
kv->name_crc = kv_hdr.name_crc;
kv->name_len = kv_hdr.name_len;
kv->value_len = kv_hdr.value_len;

if (kv->len == UINT32_MAX || kv->len > db_max_size(db) || kv->len < KV_HDR_DATA_SIZE) {
/* the KV length was not write, so reserved the info for current KV */
Expand All @@ -368,6 +379,15 @@ static fdb_err_t read_kv(fdb_kvdb_t db, fdb_kv_t kv)
//TODO Sector continuous mode, or the write length is not written completely
}

if (search_ctx) {
bool crc_match = (kv_hdr.name_crc == search_ctx->name_crc) || (kv_hdr.name_crc == 0xFFFF);
if ((kv_hdr.name_len != search_ctx->key_len) || !crc_match) {
/* skip full read for mismatched name */
kv->crc_is_ok = true;
return FDB_KV_NAME_ERR;
}
}

/* CRC32 data len(header.name_len + header.value_len + name + value), using sizeof(uint32_t) for compatible V1.x */
calc_crc32 = fdb_calc_crc32(calc_crc32, &kv_hdr.name_len, sizeof(uint32_t));
calc_crc32 = fdb_calc_crc32(calc_crc32, &kv_hdr.value_len, sizeof(uint32_t));
Expand Down Expand Up @@ -458,7 +478,7 @@ static fdb_err_t read_sector_info(fdb_kvdb_t db, uint32_t addr, kv_sec_info_t se
sector->remain = db_sec_size(db) - SECTOR_HDR_DATA_SIZE;
kv_obj.addr.start = sector->addr + SECTOR_HDR_DATA_SIZE;
do {
read_kv(db, &kv_obj);
read_kv(db, &kv_obj, NULL);
if (!kv_obj.crc_is_ok) {
if (kv_obj.status != FDB_KV_PRE_WRITE && kv_obj.status != FDB_KV_ERR_HDR) {
sector->remain = 0;
Expand Down Expand Up @@ -523,7 +543,7 @@ static uint32_t get_next_sector_addr(fdb_kvdb_t db, kv_sec_info_t pre_sec, uint3
}

static void kv_iterator(fdb_kvdb_t db, fdb_kv_t kv, void *arg1, void *arg2,
bool (*callback)(fdb_kv_t kv, void *arg1, void *arg2))
bool (*callback)(fdb_kv_t kv, void *arg1, void *arg2), const struct kv_search_ctx *search_ctx)
{
struct kvdb_sec_info sector;
uint32_t sec_addr, traversed_len = 0;
Expand All @@ -543,10 +563,11 @@ static void kv_iterator(fdb_kvdb_t db, fdb_kv_t kv, void *arg1, void *arg2,
kv->addr.start = sector.addr + SECTOR_HDR_DATA_SIZE;
/* search all KV */
do {
read_kv(db, kv);
/* iterator is interrupted when callback return true */
if (callback(kv, arg1, arg2)) {
return;
if (read_kv(db, kv, search_ctx) != FDB_KV_NAME_ERR) {
/* iterator is interrupted when callback return true */
if (callback(kv, arg1, arg2)) {
return;
}
}
} while ((kv->addr.start = get_next_kv_addr(db, &sector, kv)) != FAILED_ADDR);
}
Expand All @@ -555,15 +576,15 @@ static void kv_iterator(fdb_kvdb_t db, fdb_kv_t kv, void *arg1, void *arg2,

static bool find_kv_cb(fdb_kv_t kv, void *arg1, void *arg2)
{
const char *key = arg1;
struct kv_search_ctx *ctx = arg1;
bool *find_ok = arg2;
size_t key_len = strlen(key);
bool crc_compatible = (kv->name_crc == ctx->name_crc) || (kv->name_crc == 0xFFFF);

if (key_len != kv->name_len) {
if (ctx->key_len != kv->name_len) {
return false;
}
/* check KV */
if (kv->crc_is_ok && kv->status == FDB_KV_WRITE && !strncmp(kv->name, key, key_len)) {
if (crc_compatible && kv->crc_is_ok && kv->status == FDB_KV_WRITE && !strncmp(kv->name, ctx->key, ctx->key_len)) {
*find_ok = true;
return true;
}
Expand All @@ -573,8 +594,14 @@ static bool find_kv_cb(fdb_kv_t kv, void *arg1, void *arg2)
static bool find_kv_no_cache(fdb_kvdb_t db, const char *key, fdb_kv_t kv)
{
bool find_ok = false;
size_t key_len = strlen(key);
struct kv_search_ctx ctx = {
.key = key,
.key_len = key_len,
.name_crc = (uint16_t) (fdb_calc_crc32(0, key, key_len) >> 16),
};

kv_iterator(db, kv, (void *)key, &find_ok, find_kv_cb);
kv_iterator(db, kv, &ctx, &find_ok, find_kv_cb, &ctx);

return find_ok;
}
Expand All @@ -587,7 +614,7 @@ static bool find_kv(fdb_kvdb_t db, const char *key, fdb_kv_t kv)
size_t key_len = strlen(key);

if (get_kv_from_cache(db, key, key_len, &kv->addr.start)) {
read_kv(db, kv);
read_kv(db, kv, NULL);
return true;
}
#endif /* FDB_KV_USING_CACHE */
Expand Down Expand Up @@ -1120,7 +1147,7 @@ static bool do_gc(kv_sec_info_t sector, void *arg1, void *arg2)
/* search all KV */
kv.addr.start = sector->addr + SECTOR_HDR_DATA_SIZE;
do {
read_kv(db, &kv);
read_kv(db, &kv, NULL);
if (kv.crc_is_ok && (kv.status == FDB_KV_WRITE || kv.status == FDB_KV_PRE_DELETE)) {
/* move the KV to new space */
if (move_kv(db, &kv) != FDB_NO_ERR) {
Expand Down Expand Up @@ -1239,6 +1266,7 @@ static fdb_err_t create_kv_blob(fdb_kvdb_t db, kv_sec_info_t sector, const char
uint8_t ff = FDB_BYTE_ERASED;
/* start calculate CRC32 */
kv_hdr.crc32 = 0;
kv_hdr.name_crc = (uint16_t) (fdb_calc_crc32(0, key, kv_hdr.name_len) >> 16);
/* CRC32(header.name_len + header.value_len + name + value), using sizeof(uint32_t) for compatible V1.x */
kv_hdr.crc32 = fdb_calc_crc32(kv_hdr.crc32, &kv_hdr.name_len, sizeof(uint32_t));
kv_hdr.crc32 = fdb_calc_crc32(kv_hdr.crc32, &kv_hdr.value_len, sizeof(uint32_t));
Expand Down Expand Up @@ -1521,7 +1549,7 @@ void fdb_kv_print(fdb_kvdb_t db)
/* lock the KV cache */
db_lock(db);

kv_iterator(db, &kv, &using_size, db, print_kv_cb);
kv_iterator(db, &kv, &using_size, db, print_kv_cb, NULL);

FDB_PRINT("\nmode: next generation\n");
FDB_PRINT("size: %" PRIu32 "/%" PRIu32 " bytes.\n", (uint32_t)using_size + ((SECTOR_NUM - FDB_GC_EMPTY_SEC_THRESHOLD) * SECTOR_HDR_DATA_SIZE),
Expand Down Expand Up @@ -1676,7 +1704,7 @@ static fdb_err_t _fdb_kv_load(fdb_kvdb_t db)

__retry:
/* check all KV for recovery */
kv_iterator(db, &kv, db, NULL, check_and_recovery_kv_cb);
kv_iterator(db, &kv, db, NULL, check_and_recovery_kv_cb, NULL);
if (db->gc_request) {
gc_collect(db);
goto __retry;
Expand Down Expand Up @@ -1898,7 +1926,7 @@ bool fdb_kv_iterate(fdb_kvdb_t db, fdb_kv_iterator_t itr)
continue;
}
do {
read_kv(db, kv);
read_kv(db, kv, NULL);
if (kv->status == FDB_KV_WRITE && kv->crc_is_ok == true) {
/* We got a valid kv here. */
/* If iterator statistics is needed */
Expand Down Expand Up @@ -1954,7 +1982,7 @@ fdb_err_t fdb_kvdb_check(fdb_kvdb_t db)
kv.addr.start = sector.addr + SECTOR_HDR_DATA_SIZE;
/* search all KV */
do {
result = read_kv(db, &kv);
result = read_kv(db, &kv, NULL);
} while ((kv.addr.start = get_next_kv_addr(db, &sector, &kv)) != FAILED_ADDR && result == FDB_NO_ERR);
}
}
Expand Down