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mdbx: minor optimization around memcpy().

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Change-Id: Id0dd4ac693a4ddb6294bdb0f2fc5d2aec69d0efd
This commit is contained in:
Leonid Yuriev 2020-01-24 23:59:43 +03:00
parent ebcbcbfe31
commit 1ee1b269e6
1 changed files with 9 additions and 11 deletions
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20
src/elements/core.c
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@ -4924,8 +4924,7 @@ done:
} }
/* Copy the used portions of a non-overflow page. */ /* Copy the used portions of a non-overflow page. */
__hot static void mdbx_page_copy(MDBX_page *dst, MDBX_page *src, __hot static void mdbx_page_copy(MDBX_page *dst, MDBX_page *src, size_t psize) {
unsigned psize) {
STATIC_ASSERT(UINT16_MAX > MAX_PAGESIZE - PAGEHDRSZ); STATIC_ASSERT(UINT16_MAX > MAX_PAGESIZE - PAGEHDRSZ);
STATIC_ASSERT(MIN_PAGESIZE > PAGEHDRSZ + NODESIZE * 4); STATIC_ASSERT(MIN_PAGESIZE > PAGEHDRSZ + NODESIZE * 4);
if (!IS_LEAF2(src)) { if (!IS_LEAF2(src)) {
@ -4933,12 +4932,13 @@ __hot static void mdbx_page_copy(MDBX_page *dst, MDBX_page *src,
/* If page isn't full, just copy the used portion. Adjust /* If page isn't full, just copy the used portion. Adjust
* alignment so memcpy may copy words instead of bytes. */ * alignment so memcpy may copy words instead of bytes. */
if (unused > sizeof(void *) * 42) { if (unused >= MDBX_CACHELINE_SIZE * 2) {
lower = roundup_powerof2(lower + PAGEHDRSZ, sizeof(void *)); lower = roundup_powerof2(lower + PAGEHDRSZ, sizeof(void *));
upper = (upper + PAGEHDRSZ) & ~(sizeof(void *) - 1); upper = (upper + PAGEHDRSZ) & ~(sizeof(void *) - 1);
memcpy(dst, src, lower); memcpy(dst, src, lower);
memcpy((char *)dst + upper, (char *)src + upper, psize - upper); dst = (void *)((char *)dst + upper);
return; src = (void *)((char *)src + upper);
psize -= upper;
} }
} }
memcpy(dst, src, psize); memcpy(dst, src, psize);
@ -11611,9 +11611,9 @@ int mdbx_cursor_put(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data,
} }
/* Back up original data item */ /* Back up original data item */
memcpy(dkey.iov_base = fp + 1, olddata.iov_base,
dkey.iov_len = olddata.iov_len);
dupdata_flag = 1; dupdata_flag = 1;
dkey.iov_len = olddata.iov_len;
dkey.iov_base = memcpy(fp + 1, olddata.iov_base, olddata.iov_len);
/* Make sub-page header for the dup items, with dummy body */ /* Make sub-page header for the dup items, with dummy body */
fp->mp_flags = P_LEAF | P_DIRTY | P_SUBP; fp->mp_flags = P_LEAF | P_DIRTY | P_SUBP;
@ -12702,8 +12702,7 @@ static int mdbx_update_key(MDBX_cursor *mc, const MDBX_val *key) {
/* But even if no shift was needed, update ksize */ /* But even if no shift was needed, update ksize */
node_set_ks(node, key->iov_len); node_set_ks(node, key->iov_len);
if (key->iov_len) memcpy(node_key(node), key->iov_base, key->iov_len);
memcpy(node_key(node), key->iov_base, key->iov_len);
return MDBX_SUCCESS; return MDBX_SUCCESS;
} }
@ -14045,8 +14044,7 @@ static int mdbx_page_split(MDBX_cursor *mc, const MDBX_val *newkey,
mdbx_cassert(mc, mp->mp_upper >= ksize - sizeof(indx_t)); mdbx_cassert(mc, mp->mp_upper >= ksize - sizeof(indx_t));
mp->mp_upper -= (indx_t)(ksize - sizeof(indx_t)); mp->mp_upper -= (indx_t)(ksize - sizeof(indx_t));
} else { } else {
if (x) memcpy(rp->mp_ptrs, split, x * ksize);
memcpy(rp->mp_ptrs, split, x * ksize);
ins = page_leaf2key(rp, x, ksize); ins = page_leaf2key(rp, x, ksize);
memcpy(ins, newkey->iov_base, ksize); memcpy(ins, newkey->iov_base, ksize);
memcpy(ins + ksize, split + x * ksize, rsize - x * ksize); memcpy(ins + ksize, split + x * ksize, rsize - x * ksize);