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-rw-r--r--erts/emulator/beam/erl_lock_check.c1
-rw-r--r--erts/emulator/sys/common/erl_mmap.c142
-rw-r--r--erts/emulator/sys/common/erl_mmap.h11
-rw-r--r--erts/emulator/sys/common/erl_mseg.c6
4 files changed, 158 insertions, 2 deletions
diff --git a/erts/emulator/beam/erl_lock_check.c b/erts/emulator/beam/erl_lock_check.c
index 1e9cef3759..87efbdbc3e 100644
--- a/erts/emulator/beam/erl_lock_check.c
+++ b/erts/emulator/beam/erl_lock_check.c
@@ -186,6 +186,7 @@ static erts_lc_lock_order_t erts_lock_order[] = {
#endif
#endif
{ "erts_alloc_hard_debug", NULL },
+ { "hard_dbg_mseg", NULL },
{ "erts_mmap", NULL }
};
diff --git a/erts/emulator/sys/common/erl_mmap.c b/erts/emulator/sys/common/erl_mmap.c
index 1876398ec4..93a95e5eef 100644
--- a/erts/emulator/sys/common/erl_mmap.c
+++ b/erts/emulator/sys/common/erl_mmap.c
@@ -1039,7 +1039,7 @@ rbt_foreach_node(RBTree* tree,
#endif
}
-#ifdef RBT_DEBUG
+#if defined(RBT_DEBUG) || defined(HARD_DEBUG_MSEG)
static RBTNode* rbt_prev_node(RBTNode* node)
{
RBTNode* x;
@@ -1068,7 +1068,7 @@ static RBTNode* rbt_next_node(RBTNode* node)
}
return NULL;
}
-#endif /* RBT_DEBUG */
+#endif /* RBT_DEBUG || HARD_DEBUG_MSEG */
/* The API to keep track of a bunch of separated (free) segments
@@ -2041,6 +2041,10 @@ int erts_mmap_in_supercarrier(void *ptr)
return ERTS_MMAP_IN_SUPERCARRIER(ptr);
}
+#ifdef HARD_DEBUG_MSEG
+static void hard_dbg_mseg_init(void);
+#endif
+
void
erts_mmap_init(ErtsMMapInit *init)
{
@@ -2233,6 +2237,10 @@ erts_mmap_init(ErtsMMapInit *init)
#if !ERTS_HAVE_OS_MMAP
mmap_state.no_os_mmap = 1;
#endif
+
+#ifdef HARD_DEBUG_MSEG
+ hard_dbg_mseg_init();
+#endif
}
Eterm erts_mmap_info(Process* p)
@@ -2494,3 +2502,133 @@ void test_it(void)
}
#endif /* FREE_SEG_API_SMOKE_TEST */
+
+
+#ifdef HARD_DEBUG_MSEG
+
+/*
+ * Debug stuff used by erl_mseg to check that it does the right thing.
+ * The reason for keeping it here is that we (ab)use the rb-tree code
+ * for keeping track of *allocated* segments.
+ */
+
+typedef struct ErtsFreeSegDesc_fake_ {
+ /*RBTNode snode; Save memory by skipping unused size tree node */
+ RBTNode anode; /* node in 'atree' */
+ union {
+ char* start;
+ struct ErtsFreeSegDesc_fake_* next_free;
+ }u;
+ char* end;
+}ErtsFreeSegDesc_fake;
+
+static ErtsFreeSegDesc_fake hard_dbg_mseg_desc_pool[10000];
+static ErtsFreeSegDesc_fake* hard_dbg_mseg_desc_first;
+RBTree hard_dbg_mseg_tree;
+
+static erts_mtx_t hard_dbg_mseg_mtx;
+
+static void hard_dbg_mseg_init(void)
+{
+ ErtsFreeSegDesc_fake* p;
+
+ erts_mtx_init(&hard_dbg_mseg_mtx, "hard_dbg_mseg");
+ hard_dbg_mseg_tree.root = NULL;
+ hard_dbg_mseg_tree.order = ADDR_ORDER;
+
+ p = &hard_dbg_mseg_desc_pool[(sizeof(hard_dbg_mseg_desc_pool) /
+ sizeof(*hard_dbg_mseg_desc_pool)) - 1];
+ p->u.next_free = NULL;
+ while (--p >= hard_dbg_mseg_desc_pool) {
+ p->u.next_free = (p+1);
+ }
+ hard_dbg_mseg_desc_first = &hard_dbg_mseg_desc_pool[0];
+}
+
+static ErtsFreeSegDesc* hard_dbg_alloc_desc(void)
+{
+ ErtsFreeSegDesc_fake* p = hard_dbg_mseg_desc_first;
+ ERTS_ASSERT(p || !"HARD_DEBUG_MSEG: Out of mseg descriptors");
+ hard_dbg_mseg_desc_first = p->u.next_free;
+
+ /* Creative pointer arithmetic to return something that looks like
+ * a ErtsFreeSegDesc as long as we don't use the absent 'snode'.
+ */
+ return (ErtsFreeSegDesc*) ((char*)p - offsetof(ErtsFreeSegDesc,anode));
+}
+
+static void hard_dbg_free_desc(ErtsFreeSegDesc* desc)
+{
+ ErtsFreeSegDesc_fake* p = (ErtsFreeSegDesc_fake*) &desc->anode;
+ memset(p, 0xfe, sizeof(*p));
+ p->u.next_free = hard_dbg_mseg_desc_first;
+ hard_dbg_mseg_desc_first = p;
+}
+
+static void check_seg_writable(void* seg, UWord sz)
+{
+ UWord* seg_end = (UWord*)((char*)seg + sz);
+ volatile UWord* p;
+ ERTS_ASSERT(ERTS_IS_PAGEALIGNED(seg));
+ ERTS_ASSERT(ERTS_IS_PAGEALIGNED(sz));
+ for (p=(UWord*)seg; p<seg_end; p += (ERTS_INV_PAGEALIGNED_MASK+1)/sizeof(UWord)) {
+ UWord write_back = *p;
+ *p = 0xfade2b1acc;
+ *p = write_back;
+ }
+}
+
+void hard_dbg_insert_mseg(void* seg, UWord sz)
+{
+ check_seg_writable(seg, sz);
+ erts_mtx_lock(&hard_dbg_mseg_mtx);
+ {
+ ErtsFreeSegDesc *desc = hard_dbg_alloc_desc();
+ RBTNode *prev, *next;
+ desc->start = (char*)seg;
+ desc->end = desc->start + sz - 1; /* -1 to allow adjacent segments in tree */
+ rbt_insert(&hard_dbg_mseg_tree, &desc->anode);
+ prev = rbt_prev_node(&desc->anode);
+ next = rbt_next_node(&desc->anode);
+ ERTS_ASSERT(!prev || anode_to_desc(prev)->end < desc->start);
+ ERTS_ASSERT(!next || anode_to_desc(next)->start > desc->end);
+ }
+ erts_mtx_unlock(&hard_dbg_mseg_mtx);
+}
+
+static ErtsFreeSegDesc* hard_dbg_lookup_seg_at(RBTree* tree, char* start)
+{
+ RBTNode* x = tree->root;
+
+ while (x) {
+ ErtsFreeSegDesc* desc = anode_to_desc(x);
+ if (start < desc->start) {
+ x = x->left;
+ }
+ else if (start > desc->start) {
+ ERTS_ASSERT(start > desc->end);
+ x = x->right;
+ }
+ else
+ return desc;
+ }
+ return NULL;
+}
+
+void hard_dbg_remove_mseg(void* seg, UWord sz)
+{
+ check_seg_writable(seg, sz);
+ erts_mtx_lock(&hard_dbg_mseg_mtx);
+ {
+ ErtsFreeSegDesc* desc = hard_dbg_lookup_seg_at(&hard_dbg_mseg_tree, (char*)seg);
+ ERTS_ASSERT(desc);
+ ERTS_ASSERT(desc->start == (char*)seg);
+ ERTS_ASSERT(desc->end == (char*)seg + sz - 1);
+
+ rbt_delete(&hard_dbg_mseg_tree, &desc->anode);
+ hard_dbg_free_desc(desc);
+ }
+ erts_mtx_unlock(&hard_dbg_mseg_mtx);
+}
+
+#endif /* HARD_DEBUG_MSEG */
diff --git a/erts/emulator/sys/common/erl_mmap.h b/erts/emulator/sys/common/erl_mmap.h
index 6cb51fb0b4..106459f872 100644
--- a/erts/emulator/sys/common/erl_mmap.h
+++ b/erts/emulator/sys/common/erl_mmap.h
@@ -110,4 +110,15 @@ Eterm erts_mmap_info(struct process*);
# define ERTS_HAVE_OS_MMAP 1
#endif
+/*#define HARD_DEBUG_MSEG*/
+#ifdef HARD_DEBUG_MSEG
+# define HARD_DBG_INSERT_MSEG hard_dbg_insert_mseg
+# define HARD_DBG_REMOVE_MSEG hard_dbg_remove_mseg
+void hard_dbg_insert_mseg(void* seg, UWord sz);
+void hard_dbg_remove_mseg(void* seg, UWord sz);
+#else
+# define HARD_DBG_INSERT_MSEG(SEG,SZ)
+# define HARD_DBG_REMOVE_MSEG(SEG,SZ)
+#endif
+
#endif /* ERL_MMAP_H__ */
diff --git a/erts/emulator/sys/common/erl_mseg.c b/erts/emulator/sys/common/erl_mseg.c
index c65973b3be..13f8069cf5 100644
--- a/erts/emulator/sys/common/erl_mseg.c
+++ b/erts/emulator/sys/common/erl_mseg.c
@@ -1356,6 +1356,7 @@ erts_mseg_alloc_opt(ErtsAlcType_t atype, UWord *size_p, Uint flags, const ErtsMs
ERTS_DBG_MA_CHK_THR_ACCESS(ma);
seg = mseg_alloc(ma, atype, size_p, flags, opt);
ERTS_MSEG_UNLOCK(ma);
+ HARD_DBG_INSERT_MSEG(seg, *size_p);
return seg;
}
@@ -1370,6 +1371,8 @@ erts_mseg_dealloc_opt(ErtsAlcType_t atype, void *seg,
UWord size, Uint flags, const ErtsMsegOpt_t *opt)
{
ErtsMsegAllctr_t *ma = ERTS_MSEG_ALLCTR_OPT(opt);
+
+ HARD_DBG_REMOVE_MSEG(seg, size);
ERTS_MSEG_LOCK(ma);
ERTS_DBG_MA_CHK_THR_ACCESS(ma);
mseg_dealloc(ma, atype, seg, size, flags, opt);
@@ -1390,10 +1393,13 @@ erts_mseg_realloc_opt(ErtsAlcType_t atype, void *seg,
{
ErtsMsegAllctr_t *ma = ERTS_MSEG_ALLCTR_OPT(opt);
void *new_seg;
+
+ HARD_DBG_REMOVE_MSEG(seg, old_size);
ERTS_MSEG_LOCK(ma);
ERTS_DBG_MA_CHK_THR_ACCESS(ma);
new_seg = mseg_realloc(ma, atype, seg, old_size, new_size_p, flags, opt);
ERTS_MSEG_UNLOCK(ma);
+ HARD_DBG_INSERT_MSEG(new_seg, *new_size_p);
return new_seg;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-14 06:50:46 +0000