Add //pkg/sync:generic_atomicptrmap.

AtomicPtrMap is a generic concurrent map from arbitrary keys to arbitrary
pointer values.

Benchmarks:
name                                                            time/op
StoreDelete/RWMutexMap-12                                        335ns ± 1%
StoreDelete/SyncMap-12                                           705ns ± 3%
StoreDelete/AtomicPtrMap-12                                      287ns ± 4%
StoreDelete/AtomicPtrMapSharded-12                               289ns ± 1%
LoadOrStoreDelete/RWMutexMap-12                                  342ns ± 2%
LoadOrStoreDelete/SyncMap-12                                     662ns ± 2%
LoadOrStoreDelete/AtomicPtrMap-12                                290ns ± 7%
LoadOrStoreDelete/AtomicPtrMapSharded-12                         293ns ± 2%
LookupPositive/RWMutexMap-12                                     101ns ±26%
LookupPositive/SyncMap-12                                        202ns ± 2%
LookupPositive/AtomicPtrMap-12                                  71.1ns ± 2%
LookupPositive/AtomicPtrMapSharded-12                           73.2ns ± 1%
LookupNegative/RWMutexMap-12                                     119ns ± 1%
LookupNegative/SyncMap-12                                        154ns ± 1%
LookupNegative/AtomicPtrMap-12                                  84.7ns ± 3%
LookupNegative/AtomicPtrMapSharded-12                           86.8ns ± 1%
Concurrent/FixedKeys_1PercentWrites_RWMutexMap-12               1.32µs ± 2%
Concurrent/FixedKeys_1PercentWrites_SyncMap-12                  52.7ns ±10%
Concurrent/FixedKeys_1PercentWrites_AtomicPtrMap-12             31.8ns ±20%
Concurrent/FixedKeys_1PercentWrites_AtomicPtrMapSharded-12      24.0ns ±15%
Concurrent/FixedKeys_10PercentWrites_RWMutexMap-12               860ns ± 3%
Concurrent/FixedKeys_10PercentWrites_SyncMap-12                 68.8ns ±20%
Concurrent/FixedKeys_10PercentWrites_AtomicPtrMap-12            98.6ns ± 7%
Concurrent/FixedKeys_10PercentWrites_AtomicPtrMapSharded-12     42.0ns ±25%
Concurrent/FixedKeys_50PercentWrites_RWMutexMap-12              1.17µs ± 3%
Concurrent/FixedKeys_50PercentWrites_SyncMap-12                  136ns ±34%
Concurrent/FixedKeys_50PercentWrites_AtomicPtrMap-12             286ns ± 3%
Concurrent/FixedKeys_50PercentWrites_AtomicPtrMapSharded-12      115ns ±35%
Concurrent/ChangingKeys_1PercentWrites_RWMutexMap-12            1.27µs ± 2%
Concurrent/ChangingKeys_1PercentWrites_SyncMap-12               5.01µs ± 3%
Concurrent/ChangingKeys_1PercentWrites_AtomicPtrMap-12          38.1ns ± 3%
Concurrent/ChangingKeys_1PercentWrites_AtomicPtrMapSharded-12   22.6ns ± 2%
Concurrent/ChangingKeys_10PercentWrites_RWMutexMap-12           1.08µs ± 2%
Concurrent/ChangingKeys_10PercentWrites_SyncMap-12              5.97µs ± 1%
Concurrent/ChangingKeys_10PercentWrites_AtomicPtrMap-12          390ns ± 2%
Concurrent/ChangingKeys_10PercentWrites_AtomicPtrMapSharded-12  93.6ns ± 1%
Concurrent/ChangingKeys_50PercentWrites_RWMutexMap-12           1.77µs ± 2%
Concurrent/ChangingKeys_50PercentWrites_SyncMap-12              8.07µs ± 2%
Concurrent/ChangingKeys_50PercentWrites_AtomicPtrMap-12         1.61µs ± 2%
Concurrent/ChangingKeys_50PercentWrites_AtomicPtrMapSharded-12   386ns ± 1%

Updates #231

PiperOrigin-RevId: 346614776

1 files changed, 57 insertions, 0 deletions

diff --git a/pkg/sync/atomicptrmaptest/BUILD b/pkg/sync/atomicptrmaptest/BUILD
new file mode 100644
index 000000000..3f71ae97d
--- /dev/null
+++ b/pkg/sync/atomicptrmaptest/BUILD
@@ -0,0 +1,57 @@
+load("//tools:defs.bzl", "go_library", "go_test")
+load("//tools/go_generics:defs.bzl", "go_template_instance")
+
+package(
+    default_visibility = ["//visibility:private"],
+    licenses = ["notice"],
+)
+
+go_template_instance(
+    name = "test_atomicptrmap",
+    out = "test_atomicptrmap_unsafe.go",
+    package = "atomicptrmap",
+    prefix = "test",
+    template = "//pkg/sync:generic_atomicptrmap",
+    types = {
+        "Key": "int64",
+        "Value": "testValue",
+    },
+)
+
+go_template_instance(
+    name = "test_atomicptrmap_sharded",
+    out = "test_atomicptrmap_sharded_unsafe.go",
+    consts = {
+        "ShardOrder": "4",
+    },
+    package = "atomicptrmap",
+    prefix = "test",
+    suffix = "Sharded",
+    template = "//pkg/sync:generic_atomicptrmap",
+    types = {
+        "Key": "int64",
+        "Value": "testValue",
+    },
+)
+
+go_library(
+    name = "atomicptrmap",
+    testonly = 1,
+    srcs = [
+        "atomicptrmap.go",
+        "test_atomicptrmap_sharded_unsafe.go",
+        "test_atomicptrmap_unsafe.go",
+    ],
+    deps = [
+        "//pkg/gohacks",
+        "//pkg/sync",
+    ],
+)
+
+go_test(
+    name = "atomicptrmap_test",
+    size = "small",
+    srcs = ["atomicptrmap_test.go"],
+    library = ":atomicptrmap",
+    deps = ["//pkg/sync"],
+)