erts: Rewrite memory instrumentation

This commit replaces the old memory instrumentation with a new
implementation that scans carriers instead of wrapping
erts_alloc/erts_free. The old implementation could not extract
information without halting the emulator, had considerable runtime
overhead, and the memory maps it produced were noisy and lacked
critical information.

Since the new implementation walks through existing data structures
there's no longer a need to start the emulator with special flags to
get information about carrier utilization/fragmentation. Memory
fragmentation is also easier to diagnose as it's presented on a
per-carrier basis which eliminates the need to account for "holes"
between mmap segments.

To help track allocations, each allocation can now be tagged with
what it is and who allocated it at the cost of one extra word per
allocation. This is controlled on a per-allocator basis with the
+M<S>atags option, and is enabled by default for binary_alloc and
driver_alloc (which is also used by NIFs).

1 files changed, 17 insertions, 81 deletions

diff --git a/erts/emulator/beam/erl_alloc.c b/erts/emulator/beam/erl_alloc.c
index 061b9df627..d99d2ea57b 100644
--- a/erts/emulator/beam/erl_alloc.c
+++ b/erts/emulator/beam/erl_alloc.c
@@ -38,7 +38,7 @@
 #include "erl_db.h"
 #include "erl_binary.h"
 #include "erl_bits.h"
-#include "erl_instrument.h"
+#include "erl_mtrace.h"
 #include "erl_mseg.h"
 #include "erl_monitor_link.h"
 #include "erl_hl_timer.h"
@@ -202,8 +202,6 @@ typedef struct {
     int top_pad;
     AlcUInit_t alloc_util;
     struct {
-	int stat;
-	int map;
 	char *mtrace;
 	char *nodename;
     } instr;
@@ -428,6 +426,7 @@ set_default_binary_alloc_opts(struct au_init *ip)
 #endif
     ip->init.util.ts 		= ERTS_ALC_MTA_BINARY;
     ip->init.util.acul		= ERTS_ALC_DEFAULT_ACUL;
+    ip->init.util.atags		= 1;
 }
 
 static void
@@ -464,6 +463,7 @@ set_default_driver_alloc_opts(struct au_init *ip)
 #endif
     ip->init.util.ts 		= ERTS_ALC_MTA_DRIVER;
     ip->init.util.acul		= ERTS_ALC_DEFAULT_ACUL;
+    ip->init.util.atags		= 1;
 }
 
 static void
@@ -501,6 +501,7 @@ set_default_test_alloc_opts(struct au_init *ip)
     ip->init.util.mmbcs 	= 0; /* Main carrier size */
     ip->init.util.ts 		= ERTS_ALC_MTA_TEST;
     ip->init.util.acul		= ERTS_ALC_DEFAULT_ACUL;
+    ip->init.util.atags		= 1;
 
     /* Use a constant minimal MBC size */
 #if ERTS_SA_MB_CARRIERS
@@ -906,7 +907,6 @@ erts_alloc_init(int *argc, char **argv, ErtsAllocInitOpts *eaiop)
 		       &test_alloc_state);
 
     erts_mtrace_install_wrapper_functions();
-    extra_block_size += erts_instr_init(init.instr.stat, init.instr.map);
 
     init_aireq_alloc();
 
@@ -1411,7 +1411,9 @@ handle_au_arg(struct au_init *auip,
 	    }
 	    if (!strategy_support_carrier_migration(auip))
 		auip->init.util.acul = 0;
-	}
+	} else if (has_prefix("atags", sub_param)) {
+            auip->init.util.atags = get_bool_value(sub_param + 5, argv, ip);
+        }
 	else
 	    goto bad_switch;
 	break;
@@ -1741,24 +1743,6 @@ handle_args(int *argc, char **argv, erts_alc_hndl_args_init_t *init)
 		    break;
 		case 'i':
 		    switch (argv[i][3]) {
-		    case 's':
-			arg = get_value(argv[i]+4, argv, &i);
-			if (sys_strcmp("true", arg) == 0)
-			    init->instr.stat = 1;
-			else if (sys_strcmp("false", arg) == 0)
-			    init->instr.stat = 0;
-			else
-			    bad_value(param, param+3, arg);
-			break;
-		    case 'm':
-			arg = get_value(argv[i]+4, argv, &i);
-			if (sys_strcmp("true", arg) == 0)
-			    init->instr.map = 1;
-			else if (sys_strcmp("false", arg) == 0)
-			    init->instr.map = 0;
-			else
-			    bad_value(param, param+3, arg);
-			break;
 		    case 't':
 			init->instr.mtrace = get_value(argv[i]+4, argv, &i);
 			break;
@@ -1817,9 +1801,7 @@ handle_args(int *argc, char **argv, erts_alc_hndl_args_init_t *init)
 	    case '-':
 		if (argv[i][2] == '\0') {
 		    /* End of system flags reached */
-		    if (init->instr.mtrace
-			/* || init->instr.stat
-			   || init->instr.map */) {
+		    if (init->instr.mtrace) {
 			while (i < *argc) {
 			    if(sys_strcmp(argv[i], "-sname") == 0
 			       || sys_strcmp(argv[i], "-name") == 0) {
@@ -2097,7 +2079,7 @@ erts_memory(fmtfn_t *print_to_p, void *print_to_arg, void *proc, Eterm earg)
  * NOTE! When updating this function, make sure to also update
  *       erlang:memory/[0,1] in $ERL_TOP/erts/preloaded/src/erlang.erl
  */
-#define ERTS_MEM_NEED_ALL_ALCU (!erts_instr_stat && want_tot_or_sys)
+#define ERTS_MEM_NEED_ALL_ALCU (want_tot_or_sys)
     struct {
 	int total;
 	int processes;
@@ -2108,7 +2090,6 @@ erts_memory(fmtfn_t *print_to_p, void *print_to_arg, void *proc, Eterm earg)
 	int binary;
 	int code;
 	int ets;
-	int maximum;
     } want = {0};
     struct {
 	UWord total;
@@ -2120,7 +2101,6 @@ erts_memory(fmtfn_t *print_to_p, void *print_to_arg, void *proc, Eterm earg)
 	UWord binary;
 	UWord code;
 	UWord ets;
-	UWord maximum;
     } size = {0};
     Eterm atoms[sizeof(size)/sizeof(UWord)];
     UWord *uintps[sizeof(size)/sizeof(UWord)];
@@ -2173,12 +2153,6 @@ erts_memory(fmtfn_t *print_to_p, void *print_to_arg, void *proc, Eterm earg)
 	want.ets = 1;
 	atoms[length] = am_ets;
 	uintps[length++] = &size.ets;
-
-	want.maximum = erts_instr_stat;
-	if (want.maximum) {
-	    atoms[length] = am_maximum;
-	    uintps[length++] = &size.maximum;
-	}
     }
     else {
 	DeclareTmpHeapNoproc(tmp_heap,2);
@@ -2260,18 +2234,6 @@ erts_memory(fmtfn_t *print_to_p, void *print_to_arg, void *proc, Eterm earg)
 		    uintps[length++] = &size.ets;
 		}
 		break;
-	    case am_maximum:
-		if (erts_instr_stat) {
-		    if (!want.maximum) {
-			want.maximum = 1;
-			atoms[length] = am_maximum;
-			uintps[length++] = &size.maximum;
-		    }
-		} else {
-		    UnUseTmpHeapNoproc(2);
-		    return am_badarg;
-		}
-		break;
 	    default:
 		UnUseTmpHeapNoproc(2);
 		return am_badarg;
@@ -2437,14 +2399,7 @@ erts_memory(fmtfn_t *print_to_p, void *print_to_arg, void *proc, Eterm earg)
 	size.ets += erts_get_ets_misc_mem_size();
     }
 
-    if (erts_instr_stat && (want_tot_or_sys || want.maximum)) {
-	if (want_tot_or_sys) {
-	    size.total = erts_instr_get_total();
-	    size.system = size.total - size.processes;
-	}
-	size.maximum = erts_instr_get_max_total();
-    }
-    else if (want_tot_or_sys) {
+    if (want_tot_or_sys) {
 	size.system = size.total - size.processes;
     }
 
@@ -2522,18 +2477,6 @@ erts_allocated_areas(fmtfn_t *print_to_p, void *print_to_arg, void *proc)
 
     i = 0;
 
-    if (erts_instr_stat) {
-	values[i].arity = 2;
-	values[i].name = "total";
-	values[i].ui[0] = erts_instr_get_total();
-	i++;
-
-	values[i].arity = 2;
-	values[i].name = "maximum";
-	values[i].ui[0] = erts_instr_get_max_total();
-	i++;
-    }
-
     values[i].arity = 2;
     values[i].name = "sys_misc";
     values[i].ui[0] = erts_sys_misc_mem_sz();
@@ -2824,10 +2767,7 @@ erts_allocator_info(fmtfn_t to, void *arg)
     erts_alcu_au_info_options(&to, arg, NULL, NULL);
 
     erts_print(to, arg, "=allocator:instr\n");
-    erts_print(to, arg, "option m: %s\n",
-	       erts_instr_memory_map ? "true" : "false");
-    erts_print(to, arg, "option s: %s\n",
-	       erts_instr_stat ? "true" : "false");
+
     erts_print(to, arg, "option t: %s\n",
 	       erts_mtrace_enabled ? "true" : "false");
 
@@ -2933,16 +2873,12 @@ erts_allocator_options(void *proc)
                                              NULL, hpp, szp);
 #endif
     {
-	Eterm o[3], v[3];
-	o[0] = am_atom_put("m", 1);
-	v[0] = erts_instr_memory_map ? am_true : am_false;
-	o[1] = am_atom_put("s", 1);
-	v[1] = erts_instr_stat ? am_true : am_false;
-	o[2] = am_atom_put("t", 1);
-	v[2] = erts_mtrace_enabled ? am_true : am_false;
+	Eterm o[1], v[1];
+	o[0] = am_atom_put("t", 1);
+	v[0] = erts_mtrace_enabled ? am_true : am_false;
 
 	atoms[length] = am_atom_put("instr", 5); 
-	terms[length++] = erts_bld_2tup_list(hpp, szp, 3, o, v);
+	terms[length++] = erts_bld_2tup_list(hpp, szp, 1, o, v);
     }
 
     atoms[length] = am_atom_put("lock_physical_memory", 20);
@@ -3458,8 +3394,8 @@ badarg:
 
 /* 
  * The allocator wrapper prelocking stuff below is about the locking order.
- * It only affects wrappers (erl_mtrace.c and erl_instrument.c) that keep locks
- * during alloc/realloc/free.
+ * It only affects wrappers (erl_mtrace.c) that keep locks during
+ * alloc/realloc/free.
  *
  * Some query functions in erl_alloc_util.c lock the allocator mutex and then
  * use erts_printf that in turn may call the sys allocator through the wrappers.