project-base/server-skynet-source-3rd-jemalloc
2
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Sanity check szind on tcache flush.

Browse Source 
This adds some overhead to the tcache flush path (which is one of the
popular paths).  Guard it behind a config option.
This commit is contained in:
Qi Wang 2019-01-22 13:59:23 -08:00 committed by Qi Wang
parent b33eb26dee
commit e13400c919
3 changed files with 59 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
configure.ac
View File

@ -1403,6 +1403,22 @@ if test "x$enable_readlinkat" = "x1" ; then
fi fi
AC_SUBST([enable_readlinkat]) AC_SUBST([enable_readlinkat])
dnl Avoid the extra size checking by default
AC_ARG_ENABLE([extra-size-check],
[AS_HELP_STRING([--enable-extra-size-check],
[Perform additonal size related sanity checks])],
[if test "x$enable_extra_size_check" = "xno" ; then
enable_extra_size_check="0"
else
enable_extra_size_check="1"
fi
],
[enable_extra_size_check=="0"]
)
if test "x$enable_extra_size_check" = "x1" ; then
AC_DEFINE([JEMALLOC_EXTRA_SIZE_CHECK], [ ])
fi
AC_SUBST([enable_extra_size_check])
JE_COMPILABLE([a program using __builtin_unreachable], [ JE_COMPILABLE([a program using __builtin_unreachable], [
void foo (void) { void foo (void) {

3
include/jemalloc/internal/jemalloc_internal_defs.h.in
View File

@ -372,4 +372,7 @@
*/ */
#undef JEMALLOC_STRERROR_R_RETURNS_CHAR_WITH_GNU_SOURCE #undef JEMALLOC_STRERROR_R_RETURNS_CHAR_WITH_GNU_SOURCE
/* Performs additional size-matching sanity checks when defined. */
#undef JEMALLOC_EXTRA_SIZE_CHECK
#endif /* JEMALLOC_INTERNAL_DEFS_H_ */ #endif /* JEMALLOC_INTERNAL_DEFS_H_ */

42
src/tcache.c
View File

@ -100,6 +100,34 @@ tcache_alloc_small_hard(tsdn_t *tsdn, arena_t *arena, tcache_t *tcache,
return ret; return ret;
} }
/* Enabled with --enable-extra-size-check. */
#ifdef JEMALLOC_EXTRA_SIZE_CHECK
static void
tbin_extents_lookup_size_check(tsdn_t *tsdn, cache_bin_t *tbin, szind_t binind,
size_t nflush, extent_t **extents){
rtree_ctx_t rtree_ctx_fallback;
rtree_ctx_t *rtree_ctx = tsdn_rtree_ctx(tsdn, &rtree_ctx_fallback);
/*
* Verify that the items in the tcache all have the correct size; this
* is useful for catching sized deallocation bugs, also to fail early
* instead of corrupting metadata. Since this can be turned on for opt
* builds, avoid the branch in the loop.
*/
szind_t szind;
size_t sz_sum = binind * nflush;
for (unsigned i = 0 ; i < nflush; i++) {
rtree_extent_szind_read(tsdn, &extents_rtree,
rtree_ctx, (uintptr_t)*(tbin->avail - 1 - i), true,
&extents[i], &szind);
sz_sum -= szind;
}
if (sz_sum != 0) {
abort();
}
}
#endif
void void
tcache_bin_flush_small(tsd_t *tsd, tcache_t *tcache, cache_bin_t *tbin, tcache_bin_flush_small(tsd_t *tsd, tcache_t *tcache, cache_bin_t *tbin,
szind_t binind, unsigned rem) { szind_t binind, unsigned rem) {
@ -112,11 +140,16 @@ tcache_bin_flush_small(tsd_t *tsd, tcache_t *tcache, cache_bin_t *tbin,
assert(arena != NULL); assert(arena != NULL);
unsigned nflush = tbin->ncached - rem; unsigned nflush = tbin->ncached - rem;
VARIABLE_ARRAY(extent_t *, item_extent, nflush); VARIABLE_ARRAY(extent_t *, item_extent, nflush);
#ifndef JEMALLOC_EXTRA_SIZE_CHECK
/* Look up extent once per item. */ /* Look up extent once per item. */
for (unsigned i = 0 ; i < nflush; i++) { for (unsigned i = 0 ; i < nflush; i++) {
item_extent[i] = iealloc(tsd_tsdn(tsd), *(tbin->avail - 1 - i)); item_extent[i] = iealloc(tsd_tsdn(tsd), *(tbin->avail - 1 - i));
} }
#else
tbin_extents_lookup_size_check(tsd_tsdn(tsd), tbin, binind, nflush,
item_extent);
#endif
while (nflush > 0) { while (nflush > 0) {
/* Lock the arena bin associated with the first object. */ /* Lock the arena bin associated with the first object. */
extent_t *extent = item_extent[0]; extent_t *extent = item_extent[0];
@ -202,11 +235,16 @@ tcache_bin_flush_large(tsd_t *tsd, cache_bin_t *tbin, szind_t binind,
assert(tcache_arena != NULL); assert(tcache_arena != NULL);
unsigned nflush = tbin->ncached - rem; unsigned nflush = tbin->ncached - rem;
VARIABLE_ARRAY(extent_t *, item_extent, nflush); VARIABLE_ARRAY(extent_t *, item_extent, nflush);
#ifndef JEMALLOC_EXTRA_SIZE_CHECK
/* Look up extent once per item. */ /* Look up extent once per item. */
for (unsigned i = 0 ; i < nflush; i++) { for (unsigned i = 0 ; i < nflush; i++) {
item_extent[i] = iealloc(tsd_tsdn(tsd), *(tbin->avail - 1 - i)); item_extent[i] = iealloc(tsd_tsdn(tsd), *(tbin->avail - 1 - i));
} }
#else
tbin_extents_lookup_size_check(tsd_tsdn(tsd), tbin, binind, nflush,
item_extent);
#endif
while (nflush > 0) { while (nflush > 0) {
/* Lock the arena associated with the first object. */ /* Lock the arena associated with the first object. */
extent_t *extent = item_extent[0]; extent_t *extent = item_extent[0];