erts: Add new module 'atomics'

18 files changed, 736 insertions, 8 deletions

diff --git a/erts/doc/src/Makefile b/erts/doc/src/Makefile
index fccdd744f3..56f8f40069 100644
--- a/erts/doc/src/Makefile
+++ b/erts/doc/src/Makefile
@@ -53,19 +53,15 @@ XML_REF3_EFILES = \
 	erl_tracer.xml \
 	init.xml \
 	persistent_term.xml \
+	atomics.xml \
 	zlib.xml
 
 XML_REF3_FILES = \
+	$(XML_REF3_EFILES) \
 	driver_entry.xml \
 	erl_nif.xml \
-	erl_tracer.xml \
 	erl_driver.xml \
-	erl_prim_loader.xml \
-	erlang.xml \
-	erts_alloc.xml  \
-	init.xml \
-	persistent_term.xml \
-	zlib.xml
+	erts_alloc.xml
 
 XML_PART_FILES = \
 	part.xml
diff --git a/erts/doc/src/atomics.xml b/erts/doc/src/atomics.xml
new file mode 100644
index 0000000000..3fca92fb97
--- /dev/null
+++ b/erts/doc/src/atomics.xml
@@ -0,0 +1,183 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!DOCTYPE erlref SYSTEM "erlref.dtd">
+
+<erlref>
+  <header>
+    <copyright>
+      <year>2018</year>
+      <holder>Ericsson AB. All Rights Reserved.</holder>
+    </copyright>
+    <legalnotice>
+      Licensed under the Apache License, Version 2.0 (the "License");
+      you may not use this file except in compliance with the License.
+      You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+      Unless required by applicable law or agreed to in writing, software
+      distributed under the License is distributed on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+      See the License for the specific language governing permissions and
+      limitations under the License.
+    </legalnotice>
+
+    <title>atomics</title>
+  </header>
+  <module>atomics</module>
+  <modulesummary>Atomic Functions</modulesummary>
+  <description>
+    <p>This module provides a set of functions to do atomic operations towards
+    mutable atomic variables. The implementation utilizes only
+    atomic hardware instructions without any software level locking, which makes
+    it very efficient for concurrent access. The atomics are organized into
+    arrays with the follwing semantics:</p>
+    <list type="bulleted">
+      <item>
+	<p>Atomics are 64 bit integers.</p>
+      </item>
+      <item>
+	<p>Atomics can be represented as either signed or unsigned.</p>
+      </item>
+      <item>
+	<p>Atomics wrap around at overflow and underflow operations.</p>
+      </item>
+      <item>
+	<p>All operations guarantee atomicity. No intermediate results can be
+	seen. The result of one mutation can only be the input to one
+	following mutation.</p>
+      </item>
+      <item>
+	<p>All atomic operations are mutually ordered. If atomic B is updated
+	<em>after</em> atomic A, then that is how it will appear to any
+	concurrent readers. No one can read the new value of B and then read the
+	old value of A.</p>
+      </item>
+      <item>
+	<p>Indexes into atomic arrays are one-based. An atomic array of
+	arity N contains N atomics with index from 1 to N.</p>
+      </item>
+    </list>
+  </description>
+
+  <datatypes>
+    <datatype>
+      <name name="atomics_ref"/>
+      <desc><p>Identifies an atomic array returned from
+        <seealso marker="#new/2"><c>new/2</c></seealso>.</p>
+      </desc>
+    </datatype>
+  </datatypes>
+
+  <funcs>
+    <func>
+      <name name="new" arity="2"/>
+      <fsummary>Create atomic array</fsummary>
+      <desc>
+        <p>Create a new atomic array of <c><anno>Arity</anno></c> atomics.</p>
+	<p>Argument <c><anno>Opts</anno></c> is a list of the following possible
+	options:</p>
+	<taglist>
+	  <tag><c>{signed, boolean()}</c></tag>
+	  <item><p>Indicate if the elements of the array will be treated
+	  as signed or unsigned integers. Default is <c>true</c> (signed).</p>
+	  <p>The integer interval for signed atomics are from <c>-(1 bsl 63)</c>
+	  to <c>(1 bsl 63)-1</c> and for unsigned atomics from <c>0</c> to <c>(1
+	  bsl 64)-1</c>.</p>
+	  </item>
+	</taglist>
+      </desc>
+    </func>
+
+    <func>
+      <name name="put" arity="3"/>
+      <fsummary>Set atomic value</fsummary>
+      <desc>
+        <p>Set atomic to <c><anno>Value</anno></c>.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="get" arity="2"/>
+      <fsummary>Read atomic value</fsummary>
+      <desc>
+        <p>Read atomic value.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="add" arity="3"/>
+      <fsummary>Add to atomic</fsummary>
+      <desc>
+        <p>Add <c><anno>Incr</anno></c> to atomic.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="add_get" arity="3"/>
+      <fsummary>Atomic add and get</fsummary>
+      <desc>
+        <p>Atomic addition and return of the result.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="sub" arity="3"/>
+      <fsummary>Subtract from atomic</fsummary>
+      <desc>
+        <p>Subtract <c><anno>Decr</anno></c> from atomic.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="sub_get" arity="3"/>
+      <fsummary>Atomic sub and get</fsummary>
+      <desc>
+        <p>Atomic subtraction and return of the result.</p>
+      </desc>
+    </func>
+
+    <func>
+      <name name="exchange" arity="3"/>
+      <fsummary>Atomic exchange.</fsummary>
+      <desc>
+        <p>Atomically replaces the value of the atomic with
+	<c><anno>Desired</anno></c> and returns the value it held
+	previously.</p>
+      </desc>
+    </func>
+    
+    <func>
+    <name name="compare_exchange" arity="4"/>
+       <fsummary>Atomic compare and exchange.</fsummary>
+       <desc>
+         <p>Atomically compares the atomic with <c><anno>Expected</anno></c>,
+ 	and if those are equal, set atomic to <c><anno>Desired</anno></c>.
+ 	Returns <c>ok</c> if <c><anno>Desired</anno></c> was written. Returns
+ 	the actual atomic value if not equal to <c><anno>Expected</anno></c>.</p>
+       </desc>
+    </func>
+    
+    <func>
+      <name name="info" arity="1"/>
+      <fsummary>Get information about atomic array.</fsummary>
+      <desc>
+        <p>Return information about an atomic array in a map. The map
+	has the following keys:</p>
+	<taglist>
+	  <tag><c>size</c></tag>
+	  <item><p>The number of atomics in the array.</p></item>
+	  <tag><c>max</c></tag>
+	  <item><p>The highest possible value an atomic in this array can
+	  hold.</p></item>
+	  <tag><c>min</c></tag>
+	  <item><p>The lowest possible value an atomic in this array can
+	  hold.</p></item>
+	  <tag><c>memory</c></tag>
+	  <item><p>Approximate memory consumption for the array in
+	  bytes.</p></item>
+	</taglist>
+      </desc>
+    </func>
+
+ </funcs>
+</erlref>
diff --git a/erts/doc/src/ref_man.xml b/erts/doc/src/ref_man.xml
index ff64aa86b8..98f7bbbb8b 100644
--- a/erts/doc/src/ref_man.xml
+++ b/erts/doc/src/ref_man.xml
@@ -50,5 +50,6 @@
   <xi:include href="erts_alloc.xml"/>
   <xi:include href="erl_nif.xml"/>
   <xi:include href="erl_tracer.xml"/>
+  <xi:include href="atomics.xml"/>
 </application>
 
diff --git a/erts/doc/src/specs.xml b/erts/doc/src/specs.xml
index 1ab6cdc19e..784212dfa0 100644
--- a/erts/doc/src/specs.xml
+++ b/erts/doc/src/specs.xml
@@ -6,4 +6,5 @@
   <xi:include href="../specs/specs_init.xml"/>
   <xi:include href="../specs/specs_persistent_term.xml"/>
   <xi:include href="../specs/specs_zlib.xml"/>
+  <xi:include href="../specs/specs_atomics.xml"/>
 </specs>
diff --git a/erts/emulator/Makefile.in b/erts/emulator/Makefile.in
index d5ceb4b00b..7fa29a7f2e 100644
--- a/erts/emulator/Makefile.in
+++ b/erts/emulator/Makefile.in
@@ -648,6 +648,7 @@ PRELOAD_BEAM =	$(ERL_TOP)/erts/preloaded/ebin/otp_ring0.beam \
 		$(ERL_TOP)/erts/preloaded/ebin/erl_tracer.beam \
 		$(ERL_TOP)/erts/preloaded/ebin/erts_literal_area_collector.beam \
 		$(ERL_TOP)/erts/preloaded/ebin/erts_dirty_process_signal_handler.beam \
+		$(ERL_TOP)/erts/preloaded/ebin/atomics.beam \
 		$(ERL_TOP)/erts/preloaded/ebin/persistent_term.beam
 
 ifeq ($(TARGET),win32)
@@ -841,6 +842,7 @@ RUN_OBJS += \
 	$(OBJDIR)/erl_bif_info.o	$(OBJDIR)/erl_bif_op.o \
 	$(OBJDIR)/erl_bif_os.o		$(OBJDIR)/erl_bif_lists.o \
 	$(OBJDIR)/erl_bif_persistent.o \
+	$(OBJDIR)/erl_bif_atomics.o \
 	$(OBJDIR)/erl_bif_trace.o	$(OBJDIR)/erl_bif_unique.o \
 	$(OBJDIR)/erl_bif_wrap.o	$(OBJDIR)/erl_nfunc_sched.o \
 	$(OBJDIR)/erl_guard_bifs.o 	$(OBJDIR)/erl_dirty_bif_wrap.o \
diff --git a/erts/emulator/beam/atom.names b/erts/emulator/beam/atom.names
index 82bb620d62..a14f22b19e 100644
--- a/erts/emulator/beam/atom.names
+++ b/erts/emulator/beam/atom.names
@@ -396,6 +396,7 @@ atom microsecond
 atom microstate_accounting
 atom milli_seconds
 atom millisecond
+atom min
 atom min_heap_size
 atom min_bin_vheap_size
 atom minor
diff --git a/erts/emulator/beam/bif.tab b/erts/emulator/beam/bif.tab
index f1f34ae323..0577c5722f 100644
--- a/erts/emulator/beam/bif.tab
+++ b/erts/emulator/beam/bif.tab
@@ -710,3 +710,12 @@ bif persistent_term:get/0
 bif persistent_term:erase/1
 bif persistent_term:info/0
 bif erts_internal:erase_persistent_terms/0
+
+bif erts_internal:atomics_new/2
+bif atomics:get/2
+bif atomics:put/3
+bif atomics:add/3
+bif atomics:add_get/3
+bif atomics:exchange/3
+bif atomics:compare_exchange/4
+bif atomics:info/1
diff --git a/erts/emulator/beam/erl_alloc.types b/erts/emulator/beam/erl_alloc.types
index 3fc036a13c..aefa04a031 100644
--- a/erts/emulator/beam/erl_alloc.types
+++ b/erts/emulator/beam/erl_alloc.types
@@ -338,6 +338,7 @@ type	GC_INFO_REQ	SHORT_LIVED	SYSTEM		gc_info_request
 type	PORT_DATA_HEAP	STANDARD	SYSTEM		port_data_heap
 type    MSACC           DRIVER          SYSTEM          microstate_accounting
 type	SYS_CHECK_REQ	SHORT_LIVED	SYSTEM		system_check_request
+type	ATOMICS		STANDARD	SYSTEM		erl_bif_atomics
 
 #
 # Types used by system specific code
diff --git a/erts/emulator/beam/erl_bif_atomics.c b/erts/emulator/beam/erl_bif_atomics.c
new file mode 100644
index 0000000000..092dbb3bd3
--- /dev/null
+++ b/erts/emulator/beam/erl_bif_atomics.c
@@ -0,0 +1,256 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2018. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+/*
+ * Purpose:  High performance atomics.
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include <stddef.h> /* offsetof */
+
+#include "sys.h"
+#include "export.h"
+#include "bif.h"
+#include "erl_threads.h"
+#include "big.h"
+#include "erl_binary.h"
+#include "erl_bif_unique.h"
+#include "erl_map.h"
+
+typedef struct
+{
+    int is_signed;
+    UWord vlen;
+    erts_atomic64_t v[1];
+}AtomicsRef;
+
+static int atomics_destructor(Binary *unused)
+{
+    return 1;
+}
+
+#define OPT_SIGNED (1 << 0)
+
+BIF_RETTYPE erts_internal_atomics_new_2(BIF_ALIST_2)
+{
+    AtomicsRef* p;
+    Binary* mbin;
+    UWord i, cnt, opts;
+    Uint bytes;
+    Eterm* hp;
+
+    if (!term_to_UWord(BIF_ARG_1, &cnt)
+        || cnt == 0
+        || !term_to_UWord(BIF_ARG_2, &opts)) {
+
+        BIF_ERROR(BIF_P, BADARG);
+    }
+
+    if (cnt > (ERTS_UWORD_MAX / sizeof(p->v[0])))
+        BIF_ERROR(BIF_P, SYSTEM_LIMIT);
+
+    bytes = offsetof(AtomicsRef, v) + cnt*sizeof(p->v[0]);
+    mbin = erts_create_magic_binary_x(bytes,
+                                      atomics_destructor,
+                                      ERTS_ALC_T_ATOMICS,
+                                      0);
+    p = ERTS_MAGIC_BIN_DATA(mbin);
+    p->is_signed = opts & OPT_SIGNED;
+    p->vlen = cnt;
+    for (i=0; i < cnt; i++)
+        erts_atomic64_init_nob(&p->v[i], 0);
+    hp = HAlloc(BIF_P, ERTS_MAGIC_REF_THING_SIZE);
+    return erts_mk_magic_ref(&hp, &MSO(BIF_P), mbin);
+}
+
+static ERTS_INLINE int get_ref(Eterm ref, AtomicsRef** pp)
+{
+    Binary* mbin;
+    if (!is_internal_magic_ref(ref))
+        return 0;
+
+    mbin = erts_magic_ref2bin(ref);
+    if (ERTS_MAGIC_BIN_DESTRUCTOR(mbin) != atomics_destructor)
+        return 0;
+    *pp = ERTS_MAGIC_BIN_DATA(mbin);
+    return 1;
+}
+
+static ERTS_INLINE int get_ref_ix(Eterm ref, Eterm ix,
+                                  AtomicsRef** pp, UWord* ixp)
+{
+    return (get_ref(ref, pp)
+            && term_to_UWord(ix, ixp)
+            && --(*ixp) < (*pp)->vlen);
+}
+
+static ERTS_INLINE int get_value(AtomicsRef* p, Eterm term, erts_aint64_t *valp)
+{
+    return (p->is_signed ?
+            term_to_Sint64(term, (Sint64*)valp) :
+            term_to_Uint64(term, (Uint64*)valp));
+}
+
+static ERTS_INLINE int get_incr(AtomicsRef* p, Eterm term, erts_aint64_t *valp)
+{
+    return (term_to_Sint64(term, (Sint64*)valp)
+            || term_to_Uint64(term, (Uint64*)valp));
+}
+
+static ERTS_INLINE Eterm bld_atomic(Process* proc, AtomicsRef* p,
+                                    erts_aint64_t val)
+{
+    if (p->is_signed) {
+        if (IS_SSMALL(val))
+            return make_small((Sint) val);
+        else {
+            Uint hsz = ERTS_SINT64_HEAP_SIZE(val);
+            Eterm* hp = HAlloc(proc, hsz);
+            return erts_sint64_to_big(val, &hp);
+        }
+    }
+    else {
+        if ((Uint64)val <= MAX_SMALL)
+            return make_small((Sint) val);
+        else {
+            Uint hsz = ERTS_UINT64_HEAP_SIZE(val);
+            Eterm* hp = HAlloc(proc, hsz);
+            return erts_uint64_to_big(val, &hp);
+        }
+    }
+}
+
+BIF_RETTYPE atomics_put_3(BIF_ALIST_3)
+{
+    AtomicsRef* p;
+    UWord ix;
+    erts_aint64_t val;
+
+    if (!get_ref_ix(BIF_ARG_1, BIF_ARG_2, &p, &ix)
+        || !get_value(p, BIF_ARG_3, &val)) {
+        BIF_ERROR(BIF_P, BADARG);
+    }
+    erts_atomic64_set_mb(&p->v[ix], val);
+    return am_ok;
+}
+
+BIF_RETTYPE atomics_get_2(BIF_ALIST_2)
+{
+    AtomicsRef* p;
+    UWord ix;
+
+    if (!get_ref_ix(BIF_ARG_1, BIF_ARG_2, &p, &ix)) {
+        BIF_ERROR(BIF_P, BADARG);
+    }
+    return bld_atomic(BIF_P, p, erts_atomic64_read_mb(&p->v[ix]));
+}
+
+BIF_RETTYPE atomics_add_3(BIF_ALIST_3)
+{
+    AtomicsRef* p;
+    UWord ix;
+    erts_aint64_t incr;
+
+    if (!get_ref_ix(BIF_ARG_1, BIF_ARG_2, &p, &ix)
+        || !get_incr(p, BIF_ARG_3, &incr)) {
+        BIF_ERROR(BIF_P, BADARG);
+    }
+    erts_atomic64_add_mb(&p->v[ix], incr);
+    return am_ok;
+}
+
+BIF_RETTYPE atomics_add_get_3(BIF_ALIST_3)
+{
+    AtomicsRef* p;
+    UWord ix;
+    erts_aint64_t incr;
+
+    if (!get_ref_ix(BIF_ARG_1, BIF_ARG_2, &p, &ix)
+        || !get_incr(p, BIF_ARG_3, &incr)) {
+        BIF_ERROR(BIF_P, BADARG);
+    }
+    return bld_atomic(BIF_P, p, erts_atomic64_add_read_mb(&p->v[ix], incr));
+}
+
+BIF_RETTYPE atomics_exchange_3(BIF_ALIST_3)
+{
+    AtomicsRef* p;
+    UWord ix;
+    erts_aint64_t desired, was;
+
+    if (!get_ref_ix(BIF_ARG_1, BIF_ARG_2, &p, &ix)
+        || !get_value(p, BIF_ARG_3, &desired)) {
+        BIF_ERROR(BIF_P, BADARG);
+    }
+    was = erts_atomic64_xchg_mb(&p->v[ix], desired);
+    return bld_atomic(BIF_P, p, was);
+}
+
+BIF_RETTYPE atomics_compare_exchange_4(BIF_ALIST_4)
+{
+    AtomicsRef* p;
+    UWord ix;
+    erts_aint64_t expected, desired, was;
+
+    if (!get_ref_ix(BIF_ARG_1, BIF_ARG_2, &p, &ix)
+        || !get_value(p, BIF_ARG_3, &expected)
+        || !get_value(p, BIF_ARG_4, &desired)) {
+        BIF_ERROR(BIF_P, BADARG);
+    }
+    was = erts_atomic64_cmpxchg_mb(&p->v[ix], desired, expected);
+    return was == expected ? am_ok : bld_atomic(BIF_P, p, was);
+}
+
+BIF_RETTYPE atomics_info_1(BIF_ALIST_1)
+{
+    AtomicsRef* p;
+    Uint hsz = MAP4_SZ;
+    Eterm *hp;
+    Uint64 max;
+    Sint64 min;
+    UWord memory;
+    Eterm max_val, min_val, sz_val, mem_val;
+
+    if (!get_ref(BIF_ARG_1, &p))
+        BIF_ERROR(BIF_P, BADARG);
+
+    max = p->is_signed ? ERTS_SINT64_MAX : ERTS_UINT64_MAX;
+    min = p->is_signed ? ERTS_SINT64_MIN : 0;
+    memory = erts_magic_ref2bin(BIF_ARG_1)->orig_size;
+
+    erts_bld_uint64(NULL, &hsz, max);
+    erts_bld_sint64(NULL, &hsz, min);
+    erts_bld_uword(NULL, &hsz, p->vlen);
+    erts_bld_uword(NULL, &hsz, memory);
+
+    hp = HAlloc(BIF_P, hsz);
+    max_val = erts_bld_uint64(&hp, NULL, max);
+    min_val = erts_bld_sint64(&hp, NULL, min);
+    sz_val  = erts_bld_uword(&hp, NULL, p->vlen);
+    mem_val = erts_bld_uword(&hp, NULL, memory);
+
+    return MAP4(hp, am_max, max_val,
+                am_memory, mem_val,
+                am_min, min_val,
+                am_size, sz_val);
+}
diff --git a/erts/emulator/beam/sys.h b/erts/emulator/beam/sys.h
index bb22548587..869a575cb4 100644
--- a/erts/emulator/beam/sys.h
+++ b/erts/emulator/beam/sys.h
@@ -325,6 +325,7 @@ typedef long          Sint  erts_align_attribute(sizeof(long));
 #define UWORD_CONSTANT(Const) Const##UL
 #define ERTS_UWORD_MAX ULONG_MAX
 #define ERTS_SWORD_MAX LONG_MAX
+#define ERTS_SWORD_MIN LONG_MIN
 #define ERTS_SIZEOF_ETERM SIZEOF_LONG
 #define ErtsStrToSint strtol
 #elif SIZEOF_VOID_P == SIZEOF_INT
@@ -335,6 +336,7 @@ typedef int          Sint  erts_align_attribute(sizeof(int));
 #define UWORD_CONSTANT(Const) Const##U
 #define ERTS_UWORD_MAX UINT_MAX
 #define ERTS_SWORD_MAX INT_MAX
+#define ERTS_SWORD_MIN INT_MIN
 #define ERTS_SIZEOF_ETERM SIZEOF_INT
 #define ErtsStrToSint strtol
 #elif SIZEOF_VOID_P == SIZEOF_LONG_LONG
@@ -345,6 +347,7 @@ typedef long long          Sint  erts_align_attribute(sizeof(long long));
 #define UWORD_CONSTANT(Const) Const##ULL
 #define ERTS_UWORD_MAX ULLONG_MAX
 #define ERTS_SWORD_MAX LLONG_MAX
+#define ERTS_SWORD_MIN LLONG_MIN
 #define ERTS_SIZEOF_ETERM SIZEOF_LONG_LONG
 #if defined(__WIN32__)
 #define ErtsStrToSint _strtoi64
diff --git a/erts/emulator/test/Makefile b/erts/emulator/test/Makefile
index d201ea6ee1..fc395899b8 100644
--- a/erts/emulator/test/Makefile
+++ b/erts/emulator/test/Makefile
@@ -33,6 +33,7 @@ MODULES= \
 	after_SUITE \
 	alloc_SUITE \
 	async_ports_SUITE \
+	atomics_SUITE \
 	beam_SUITE \
 	beam_literals_SUITE \
 	bif_SUITE \
diff --git a/erts/emulator/test/atomics_SUITE.erl b/erts/emulator/test/atomics_SUITE.erl
new file mode 100644
index 0000000000..8c42354770
--- /dev/null
+++ b/erts/emulator/test/atomics_SUITE.erl
@@ -0,0 +1,147 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2018. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(atomics_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+
+-compile(export_all).
+
+suite() -> [{ct_hooks,[ts_install_cth]}].
+
+all() ->
+    [signed, unsigned, bad, signed_limits, unsigned_limits].
+
+signed(Config) when is_list(Config) ->
+    Size = 10,
+    Ref = atomics:new(Size,[]),
+    #{size:=Size, memory:=Memory} = atomics:info(Ref),
+    {_,true} = {Memory, Memory > Size*8},
+    {_,true} = {Memory, Memory < Size*max_atomic_sz() + 100},
+    [signed_do(Ref, Ix) || Ix <- lists:seq(1, Size)],
+    ok.
+
+signed_do(Ref, Ix) ->
+    0 = atomics:get(Ref, Ix),
+    ok = atomics:put(Ref, Ix, 3),
+    ok = atomics:add(Ref, Ix, 14),
+    17 = atomics:get(Ref, Ix),
+    20 = atomics:add_get(Ref, Ix, 3),
+    -3 = atomics:add_get(Ref, Ix, -23),
+    17 = atomics:add_get(Ref, Ix, 20),
+    ok = atomics:sub(Ref, Ix, 4),
+    13 = atomics:get(Ref, Ix),
+    -7 = atomics:sub_get(Ref, Ix, 20),
+    3  = atomics:sub_get(Ref, Ix, -10),
+    3  = atomics:exchange(Ref, Ix, 666),
+    ok = atomics:compare_exchange(Ref, Ix, 666, 777),
+    777 = atomics:compare_exchange(Ref, Ix, 666, -666),
+    ok.
+
+unsigned(Config) when is_list(Config) ->
+    Size = 10,
+    Ref = atomics:new(Size,[{signed, false}]),
+    #{size:=Size, memory:=Memory} = atomics:info(Ref),
+    true = Memory > Size*8,
+    true = Memory < Size*max_atomic_sz() + 100,
+    [unsigned_do(Ref, Ix) || Ix <- lists:seq(1, Size)],
+    ok.
+
+unsigned_do(Ref, Ix) ->
+    0 = atomics:get(Ref, Ix),
+    ok = atomics:put(Ref, Ix, 3),
+    ok = atomics:add(Ref, Ix, 14),
+    17 = atomics:get(Ref, Ix),
+    20 = atomics:add_get(Ref, Ix, 3),
+    ok = atomics:sub(Ref, Ix, 7),
+    13 = atomics:get(Ref, Ix),
+    3  = atomics:sub_get(Ref, Ix, 10),
+    3  = atomics:exchange(Ref, Ix, 666),
+    ok = atomics:compare_exchange(Ref, Ix, 666, 777),
+    777 = atomics:compare_exchange(Ref, Ix, 666, 888),
+    ok.
+
+bad(Config) when is_list(Config) ->
+    {'EXIT',{badarg,_}} = (catch atomics:new(0,[])),
+    {'EXIT',{badarg,_}} = (catch atomics:new(10,[bad])),
+    {'EXIT',{badarg,_}} = (catch atomics:new(10,[{signed,bad}])),
+    {'EXIT',{badarg,_}} = (catch atomics:new(10,[{signed,true}, bad])),
+    {'EXIT',{badarg,_}} = (catch atomics:new(10,[{signed,false} | bad])),
+    Ref = atomics:new(10,[]),
+    {'EXIT',{badarg,_}} = (catch atomics:get(1742, 7)),
+    {'EXIT',{badarg,_}} = (catch atomics:get(make_ref(), 7)),
+    {'EXIT',{badarg,_}} = (catch atomics:get(Ref, -1)),
+    {'EXIT',{badarg,_}} = (catch atomics:get(Ref, 0)),
+    {'EXIT',{badarg,_}} = (catch atomics:get(Ref, 11)),
+    {'EXIT',{badarg,_}} = (catch atomics:get(Ref, 7.0)),
+    ok.
+
+
+signed_limits(Config) when is_list(Config) ->
+    Bits = 64,
+    Max = (1 bsl (Bits-1)) - 1,
+    Min = -(1 bsl (Bits-1)),
+
+    Ref = atomics:new(1,[{signed, true}]),
+    #{max:=Max, min:=Min} = atomics:info(Ref),
+    0 = atomics:get(Ref, 1),
+    ok = atomics:add(Ref, 1, Max),
+    Min = atomics:add_get(Ref, 1, 1),
+    Max = atomics:sub_get(Ref, 1, 1),
+
+    IncrMax = (Max bsl 1) bor 1,
+    ok = atomics:put(Ref, 1, 0),
+    ok = atomics:add(Ref, 1, IncrMax),
+    -1 = atomics:get(Ref, 1),
+    {'EXIT',{badarg,_}} = (catch atomics:add(Ref, 1, IncrMax+1)),
+    {'EXIT',{badarg,_}} = (catch atomics:add(Ref, 1, Min-1)),
+
+    ok.
+
+unsigned_limits(Config) when is_list(Config) ->
+    Bits = 64,
+    Max = (1 bsl Bits) - 1,
+    Min = 0,
+
+    Ref = atomics:new(1,[{signed,false}]),
+    #{max:=Max, min:=Min} = atomics:info(Ref),
+    0 = atomics:get(Ref, 1),
+    ok = atomics:add(Ref, 1, Max),
+    Min = atomics:add_get(Ref, 1, 1),
+    Max = atomics:sub_get(Ref, 1, 1),
+
+    {'EXIT',{badarg,_}} = (catch atomics:add(Ref, 1, Max+1)),
+    IncrMin = -(1 bsl (Bits-1)),
+    ok = atomics:put(Ref, 1, -IncrMin),
+    ok = atomics:add(Ref, 1, IncrMin),
+    0 = atomics:get(Ref, 1),
+    {'EXIT',{badarg,_}} = (catch atomics:add(Ref, 1, IncrMin-1)),
+
+    ok.
+
+max_atomic_sz() ->
+    case erlang:system_info({wordsize, external}) of
+        4 -> 16;
+        8 ->
+            EI = erlang:system_info(ethread_info),
+            case lists:keyfind("64-bit native atomics", 1, EI) of
+                {_, "no", _} -> 16;
+                _ -> 8
+            end
+    end.
diff --git a/erts/preloaded/ebin/atomics.beam b/erts/preloaded/ebin/atomics.beam
new file mode 100644
index 0000000000..1de97fa668
--- /dev/null
+++ b/erts/preloaded/ebin/atomics.beam
diff --git a/erts/preloaded/ebin/erts_internal.beam b/erts/preloaded/ebin/erts_internal.beam
index f39c7aa8eb..1ddd367ef5 100644
--- a/erts/preloaded/ebin/erts_internal.beam
+++ b/erts/preloaded/ebin/erts_internal.beam
diff --git a/erts/preloaded/src/Makefile b/erts/preloaded/src/Makefile
index e768a8edbc..469086a992 100644
--- a/erts/preloaded/src/Makefile
+++ b/erts/preloaded/src/Makefile
@@ -48,6 +48,7 @@ PRE_LOADED_ERL_MODULES = \
 	erl_tracer \
 	erts_literal_area_collector \
 	erts_dirty_process_signal_handler \
+	atomics \
         persistent_term
 
 PRE_LOADED_BEAM_MODULES = \
diff --git a/erts/preloaded/src/atomics.erl b/erts/preloaded/src/atomics.erl
new file mode 100644
index 0000000000..d1fe5e65cf
--- /dev/null
+++ b/erts/preloaded/src/atomics.erl
@@ -0,0 +1,119 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2018. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+%% Purpose : Main atomics API module.
+
+-module(atomics).
+
+-export([new/2,
+         put/3, get/2,
+         add/3, add_get/3,
+         sub/3, sub_get/3,
+         exchange/3, compare_exchange/4,
+         info/1]).
+
+-export_type([atomics_ref/0]).
+
+-opaque atomics_ref() :: reference().
+
+-define(OPT_SIGNED, (1 bsl 0)).
+-define(OPT_DEFAULT, ?OPT_SIGNED).
+
+-spec new(Arity, Opts) -> atomics_ref() when
+      Arity :: pos_integer(),
+      Opts :: [Opt],
+      Opt :: {signed, boolean()}.
+new(Arity, Opts) ->
+    erts_internal:atomics_new(Arity, encode_opts(Opts, ?OPT_DEFAULT)).
+
+encode_opts([{signed, true}|T], Acc) ->
+    encode_opts(T, Acc bor ?OPT_SIGNED);
+encode_opts([{signed, false}|T], Acc) ->
+    encode_opts(T, Acc band (bnot ?OPT_SIGNED));
+encode_opts([], Acc) ->
+    Acc;
+encode_opts(_, _) ->
+    erlang:error(badarg).
+
+-spec put(Ref, Ix, Value) -> ok when
+      Ref  :: atomics_ref(),
+      Ix :: integer(),
+      Value :: integer().
+put(_Ref, _Ix, _Value) ->
+    erlang:nif_error(undef).
+
+-spec get(Ref, Ix) -> integer() when
+      Ref  :: atomics_ref(),
+      Ix :: integer().
+get(_Ref, _Ix) ->
+    erlang:nif_error(undef).
+
+-spec add(Ref, Ix, Incr) -> ok when
+      Ref  :: atomics_ref(),
+      Ix :: integer(),
+      Incr :: integer().
+add(_Ref, _Ix, _Incr) ->
+    erlang:nif_error(undef).
+
+-spec add_get(Ref, Ix, Incr) -> integer() when
+      Ref  :: atomics_ref(),
+      Ix :: integer(),
+      Incr :: integer().
+add_get(_Ref, _Ix, _Incr) ->
+    erlang:nif_error(undef).
+
+-spec sub(Ref, Ix, Decr) -> ok when
+      Ref  :: atomics_ref(),
+      Ix :: integer(),
+      Decr :: integer().
+sub(Ref, Ix, Decr) ->
+    ?MODULE:add(Ref, Ix, -Decr).
+
+-spec sub_get(Ref, Ix, Decr) -> integer() when
+      Ref  :: atomics_ref(),
+      Ix :: integer(),
+      Decr :: integer().
+sub_get(Ref, Ix, Decr) ->
+    ?MODULE:add_get(Ref, Ix, -Decr).
+
+-spec exchange(Ref, Ix, Desired) -> integer() when
+      Ref  :: atomics_ref(),
+      Ix :: integer(),
+      Desired :: integer().
+exchange(_Ref, _Ix, _Desired) ->
+    erlang:nif_error(undef).
+
+-spec compare_exchange(Ref, Ix, Expected, Desired) -> ok | integer() when
+      Ref  :: atomics_ref(),
+      Ix :: integer(),
+      Expected :: integer(),
+      Desired :: integer().
+compare_exchange(_Ref, _Ix, _Expected, _Desired) ->
+    erlang:nif_error(undef).
+
+-spec info(Ref) -> Info when
+      Ref  :: atomics_ref(),
+      Info :: #{'size':=Size,'max':=Max,'min':=Min,'memory':=Memory},
+      Size :: non_neg_integer(),
+      Max :: integer(),
+      Min :: integer(),
+      Memory :: non_neg_integer().
+info(_Ref) ->
+    erlang:nif_error(undef).
diff --git a/erts/preloaded/src/erts.app.src b/erts/preloaded/src/erts.app.src
index 8c34c99a98..c6b82170d3 100644
--- a/erts/preloaded/src/erts.app.src
+++ b/erts/preloaded/src/erts.app.src
@@ -33,12 +33,13 @@
 		prim_file,
 		prim_inet,
 		prim_zip,
+                atomics,
 		zlib
 	    ]},
 	{registered, []},
 	{applications, []},
 	{env, []},
-	{runtime_dependencies, ["stdlib-3.5", "kernel-6.1", "sasl-3.0.1"]}
+	{runtime_dependencies, ["stdlib-3.5", "kernel-6.1", "sasl-@OTP-13468@"]}
     ]}.
 
 %% vim: ft=erlang
diff --git a/erts/preloaded/src/erts_internal.erl b/erts/preloaded/src/erts_internal.erl
index 63b786a473..64c80a72c3 100644
--- a/erts/preloaded/src/erts_internal.erl
+++ b/erts/preloaded/src/erts_internal.erl
@@ -92,6 +92,8 @@
 
 -export([erase_persistent_terms/0]).
 
+-export([atomics_new/2]).
+
 %%
 %% Await result of send to port
 %%
@@ -697,3 +699,7 @@ create_dist_channel(_Node, _DistCtrlr, _Flags, _Ver) ->
 -spec erase_persistent_terms() -> 'ok'.
 erase_persistent_terms() ->
     erlang:nif_error(undefined).
+
+-spec atomics_new(pos_integer(), pos_integer()) -> reference().
+atomics_new(_Arity, _EncOpts) ->
+    erlang:nif_error(undef).