Don't dump literal areas that are not referenced at all

5 files changed, 122 insertions, 18 deletions

diff --git a/erts/emulator/beam/beam_ranges.c b/erts/emulator/beam/beam_ranges.c
index 9b0335e83d..fac4289271 100644
--- a/erts/emulator/beam/beam_ranges.c
+++ b/erts/emulator/beam/beam_ranges.c
@@ -32,6 +32,15 @@ typedef struct {
     erts_smp_atomic_t end; /* (BeamInstr*) Points one word beyond last function in module. */
 } Range;
 
+/*
+ * Used for crash dumping of literals. The size of erts_dump_lit_areas is
+ * always twice the number of active ranges (to allow for literals in both
+ * current and old code).
+ */
+
+ErtsLiteralArea** erts_dump_lit_areas;
+Uint erts_dump_num_lit_areas;
+
 /* Range 'end' needs to be atomic as we purge module
     by setting end=start in active code_ix */
 #define RANGE_END(R) ((BeamInstr*)erts_smp_atomic_read_nob(&(R)->end))
@@ -97,6 +106,11 @@ erts_init_ranges(void)
 	r[i].allocated = 0;
 	erts_smp_atomic_init_nob(&r[i].mid, 0);
     }
+
+    erts_dump_num_lit_areas = 8;
+    erts_dump_lit_areas = (ErtsLiteralArea **)
+        erts_alloc(ERTS_ALC_T_CRASH_DUMP,
+                   erts_dump_num_lit_areas * sizeof(ErtsLiteralArea*));
 }
 
 void
@@ -164,6 +178,14 @@ erts_end_staging_ranges(int commit)
 	erts_smp_atomic_set_nob(&r[dst].mid,
 				(erts_aint_t) (r[dst].modules +
 					       r[dst].n / 2));
+
+        if (r[dst].allocated * 2 > erts_dump_num_lit_areas) {
+            erts_dump_num_lit_areas *= 2;
+            erts_dump_lit_areas = (ErtsLiteralArea **)
+                erts_realloc(ERTS_ALC_T_CRASH_DUMP,
+                             (void *) erts_dump_lit_areas,
+                             erts_dump_num_lit_areas * sizeof(ErtsLiteralArea*));
+        }
     }
 }
 
diff --git a/erts/emulator/beam/erl_alloc.types b/erts/emulator/beam/erl_alloc.types
index 50a1d97dd5..252bf1cc7e 100644
--- a/erts/emulator/beam/erl_alloc.types
+++ b/erts/emulator/beam/erl_alloc.types
@@ -285,6 +285,7 @@ type    MREF_ENT	STANDARD	SYSTEM		magic_ref_entry
 type	MREF_TAB_BKTS	STANDARD	SYSTEM		magic_ref_table_buckets
 type	MREF_TAB	LONG_LIVED	SYSTEM		magic_ref_table
 type	MINDIRECTION	FIXED_SIZE	SYSTEM		magic_indirection
+type	CRASH_DUMP	STANDARD	SYSTEM		crash_dump
 
 +if threads_no_smp
 # Need thread safe allocs, but std_alloc and fix_alloc are not;
diff --git a/erts/emulator/beam/erl_process_dump.c b/erts/emulator/beam/erl_process_dump.c
index d893853063..9fd024cae8 100644
--- a/erts/emulator/beam/erl_process_dump.c
+++ b/erts/emulator/beam/erl_process_dump.c
@@ -52,9 +52,11 @@ static void print_function_from_pc(fmtfn_t to, void *to_arg, BeamInstr* x);
 static void heap_dump(fmtfn_t to, void *to_arg, Eterm x);
 static void dump_binaries(fmtfn_t to, void *to_arg, Binary* root);
 static void dump_externally(fmtfn_t to, void *to_arg, Eterm term);
+static void mark_literal(Eterm* ptr);
+static void init_literal_areas(void);
 static void dump_literals(fmtfn_t to, void *to_arg);
 static void dump_module_literals(fmtfn_t to, void *to_arg,
-                                 struct erl_module_instance* mp);
+                                 ErtsLiteralArea* lit_area);
 
 static Binary* all_binaries;
 
@@ -68,7 +70,8 @@ erts_deep_process_dump(fmtfn_t to, void *to_arg)
     int i, max = erts_ptab_max(&erts_proc);
 
     all_binaries = NULL;
-    
+    init_literal_areas();
+
     for (i = 0; i < max; i++) {
 	Process *p = erts_pix2proc(i);
 	if (p && p->i != ENULL) {
@@ -377,7 +380,9 @@ heap_dump(fmtfn_t to, void *to_arg, Eterm x)
 	    next = (Eterm *) x;
 	} else if (is_list(x)) {
 	    ptr = list_val(x);
-	    if (ptr[0] != OUR_NIL && !erts_is_literal(x, ptr)) {
+            if (erts_is_literal(x, ptr)) {
+                mark_literal(ptr);
+            } else if (ptr[0] != OUR_NIL) {
 		erts_print(to, to_arg, PTR_FMT ":l", ptr);
 		dump_element(to, to_arg, ptr[0]);
 		erts_putc(to, to_arg, '|');
@@ -396,7 +401,9 @@ heap_dump(fmtfn_t to, void *to_arg, Eterm x)
 
 	    ptr = boxed_val(x);
 	    hdr = *ptr;
-	    if (hdr != OUR_NIL && !erts_is_literal(x, ptr)) {
+            if (erts_is_literal(x, ptr)) {
+                mark_literal(ptr);
+            } else if (hdr != OUR_NIL) {
 		erts_print(to, to_arg, PTR_FMT ":", ptr);
 	        if (is_arity_value(hdr)) {
 		    Uint i;
@@ -642,42 +649,115 @@ dump_externally(fmtfn_t to, void *to_arg, Eterm term)
     }
 }
 
+/*
+ * Handle dumping of literal areas.
+ */
+
+static ErtsLiteralArea** lit_areas;
+static Uint num_lit_areas;
+
+static int compare_areas(const void * a, const void * b)
+{
+    ErtsLiteralArea** a_p = (ErtsLiteralArea **) a;
+    ErtsLiteralArea** b_p = (ErtsLiteralArea **) b;
+
+    if (*a_p < *b_p) {
+        return -1;
+    } else if (*b_p < *a_p) {
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
+
 static void
-dump_literals(fmtfn_t to, void *to_arg)
+init_literal_areas(void)
 {
     int i;
     Module* modp;
     ErtsCodeIndex code_ix;
+    ErtsLiteralArea** area_p;
 
     code_ix = erts_active_code_ix();
     erts_rlock_old_code(code_ix);
 
-    erts_print(to, to_arg, "=literals\n");
-
+    lit_areas = area_p = erts_dump_lit_areas;
+    num_lit_areas = 0;
     for (i = 0; i < module_code_size(code_ix); i++) {
 	modp = module_code(i, code_ix);
         if (modp == NULL) {
             continue;
         }
-        dump_module_literals(to, to_arg, &modp->curr);
-        dump_module_literals(to, to_arg, &modp->old);
+        if (modp->curr.code_length > 0 &&
+            modp->curr.code_hdr->literal_area) {
+            *area_p++ = modp->curr.code_hdr->literal_area;
+        }
+        if (modp->old.code_length > 0 && modp->old.code_hdr->literal_area) {
+            *area_p++ = modp->old.code_hdr->literal_area;
+        }
+    }
+
+    num_lit_areas = area_p - lit_areas;
+    ASSERT(num_lit_areas <= erts_dump_num_lit_areas);
+    for (i = 0; i < num_lit_areas; i++) {
+        lit_areas[i]->off_heap = 0;
+    }
+
+    qsort(lit_areas, num_lit_areas, sizeof(ErtsLiteralArea *),
+          compare_areas);
+
+    erts_runlock_old_code(code_ix);
+}
+
+static int search_areas(const void * a, const void * b) {
+    Eterm* key = (Eterm *) a;
+    ErtsLiteralArea** b_p = (ErtsLiteralArea **) b;
+    if (key < b_p[0]->start) {
+        return -1;
+    } else if (b_p[0]->end <= key) {
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
+static void mark_literal(Eterm* ptr)
+{
+    ErtsLiteralArea** ap;
+
+    ap = bsearch(ptr, lit_areas, num_lit_areas, sizeof(ErtsLiteralArea*),
+                 search_areas);
+    ASSERT(ap);
+    ap[0]->off_heap = (struct erl_off_heap_header *) 1;
+}
+
+
+static void
+dump_literals(fmtfn_t to, void *to_arg)
+{
+    ErtsCodeIndex code_ix;
+    int i;
+
+    code_ix = erts_active_code_ix();
+    erts_rlock_old_code(code_ix);
+
+    erts_print(to, to_arg, "=literals\n");
+    for (i = 0; i < num_lit_areas; i++) {
+        if (lit_areas[i]->off_heap) {
+            dump_module_literals(to, to_arg, lit_areas[i]);
+        }
     }
+
     erts_runlock_old_code(code_ix);
 }
 
 static void
-dump_module_literals(fmtfn_t to, void *to_arg, struct erl_module_instance* mp)
+dump_module_literals(fmtfn_t to, void *to_arg, ErtsLiteralArea* lit_area)
 {
-    BeamCodeHeader* code;
-    ErtsLiteralArea* lit_area;
     Eterm* htop;
     Eterm* hend;
 
-    if (mp->code_length == 0) {
-        return;
-    }
-    code = mp->code_hdr;
-    lit_area = code->literal_area;
     htop = lit_area->start;
     hend = lit_area->end;
     while (htop < hend) {
diff --git a/erts/emulator/beam/global.h b/erts/emulator/beam/global.h
index 182d3aa44e..440723aea6 100644
--- a/erts/emulator/beam/global.h
+++ b/erts/emulator/beam/global.h
@@ -955,6 +955,8 @@ void erts_update_ranges(BeamInstr* code, Uint size);
 void erts_remove_from_ranges(BeamInstr* code);
 UWord erts_ranges_sz(void);
 void erts_lookup_function_info(FunctionInfo* fi, BeamInstr* pc, int full_info);
+ErtsLiteralArea** erts_dump_lit_areas;
+Uint erts_dump_num_lit_areas;
 
 /* break.c */
 void init_break_handler(void);
diff --git a/erts/emulator/beam/module.c b/erts/emulator/beam/module.c
index 7987cb2eb5..a386407ec2 100644
--- a/erts/emulator/beam/module.c
+++ b/erts/emulator/beam/module.c
@@ -256,4 +256,3 @@ void module_end_staging(int commit)
 
     IF_DEBUG(dbg_load_code_ix = -1);
 }
-