ISAR/libmdbx
3
0
Fork 0
mirror of https://github.com/isar/libmdbx.git synced 2025-02-01 06:58:21 +08:00
Code Issues Packages Projects Releases Wiki Activity

mdbx: оптимизация page_copy() для LEAF2 и добавление параноидального контроля от переполнения.

Browse Source
This commit is contained in:
Леонид Юрьев (Leonid Yuriev) 2022-11-16 11:48:02 +03:00
parent e518edcfed
commit 3e05d1a427
1 changed files with 33 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

45
src/core.c
View File

@ -752,7 +752,7 @@ __cold static const char *pagetype_caption(const uint8_t type,
}
}
__cold static __must_check_result int MDBX_PRINTF_ARGS(2, 3)
__cold static int MDBX_PRINTF_ARGS(2, 3)
bad_page(const MDBX_page *mp, const char *fmt, ...) {
if (LOG_ENABLED(MDBX_LOG_ERROR)) {
static const MDBX_page *prev;
@ -7232,26 +7232,47 @@ __hot static pgr_t page_alloc(const MDBX_cursor *mc) {
return page_alloc_slowpath(mc, 1, MDBX_ALLOC_ALL);
}
/* Copy the used portions of a non-large/overflow page. */
__hot static void page_copy(MDBX_page *dst, const MDBX_page *src,
size_t psize) {
/* Copy the used portions of a page. */
__hot static void page_copy(MDBX_page *const dst, const MDBX_page *const src,
const size_t size) {
STATIC_ASSERT(UINT16_MAX > MAX_PAGESIZE - PAGEHDRSZ);
STATIC_ASSERT(MIN_PAGESIZE > PAGEHDRSZ + NODESIZE * 4);
char *copy_dst = (void *)dst;
const char *copy_src = (const void *)src;
size_t copy_len = size;
if (src->mp_flags & P_LEAF2) {
copy_len = PAGEHDRSZ + src->mp_leaf2_ksize * page_numkeys(src);
if (unlikely(copy_len > size))
goto bailout;
}
if ((src->mp_flags & (P_LEAF2 | P_OVERFLOW)) == 0) {
size_t upper = src->mp_upper, lower = src->mp_lower, unused = upper - lower;
size_t upper = src->mp_upper, lower = src->mp_lower;
intptr_t unused = upper - lower;
/* If page isn't full, just copy the used portion. Adjust
* alignment so memcpy may copy words instead of bytes. */
if (unused >= MDBX_CACHELINE_SIZE * 2) {
if (unused > MDBX_CACHELINE_SIZE * 3) {
lower = ceil_powerof2(lower + PAGEHDRSZ, sizeof(void *));
upper = floor_powerof2(upper + PAGEHDRSZ, sizeof(void *));
memcpy(dst, src, lower);
dst = (void *)((char *)dst + upper);
src = (void *)((char *)src + upper);
psize -= upper;
if (unlikely(upper > copy_len))
goto bailout;
memcpy(copy_dst, copy_src, lower);
copy_dst += upper;
copy_src += upper;
copy_len -= upper;
}
}
memcpy(dst, src, psize);
memcpy(copy_dst, copy_src, copy_len);
return;
bailout:
if (src->mp_flags & P_LEAF2)
bad_page(src, "%s addr %p, n-keys %zu, ksize %u",
"invalid/corrupted source page", __Wpedantic_format_voidptr(src),
page_numkeys(src), src->mp_leaf2_ksize);
else
bad_page(src, "%s addr %p, upper %u", "invalid/corrupted source page",
__Wpedantic_format_voidptr(src), src->mp_upper);
memset(dst, -1, size);
}
/* Pull a page off the txn's spill list, if present.