update

runtime/src/bpf_map/userspace/per_cpu_array_map.cpp

@@ -4,6 +4,7 @@
  * All rights reserved.
  */
 #include "bpf_map/map_common_def.hpp"
+#include "linux/bpf.h"
 #include "spdlog/spdlog.h"
 #include <algorithm>
 #include <bpf_map/userspace/per_cpu_array_map.hpp>
@@ -39,7 +40,7 @@ void *per_cpu_array_map_impl::elem_lookup(const void *key)
 		}
 		uint32_t key_val = *(uint32_t *)key;
 		if (key_val >= max_ent) {
-			errno = E2BIG;
+			errno = ENOENT;
 			return nullptr;
 		}
 		return data_at(key_val, cpu);
@@ -49,13 +50,19 @@ void *per_cpu_array_map_impl::elem_lookup(const void *key)
 long per_cpu_array_map_impl::elem_update(const void *key, const void *value,
 					 uint64_t flags)
 {
+	if (!check_update_flags(flags))
+		return -1;
 	return ensure_on_current_cpu<long>([&](int cpu) -> long {
 		// return impl[cpu].elem_update(key, value, flags);
 		if (key == nullptr) {
 			errno = ENOENT;
 			return -1;
 		}
 		uint32_t key_val = *(uint32_t *)key;
+		if (key_val < max_ent && flags == BPF_NOEXIST) {
+			errno = EEXIST;
+			return -1;
+		}
 		if (key_val >= max_ent) {
 			errno = E2BIG;
 			return -1;
@@ -68,13 +75,12 @@ long per_cpu_array_map_impl::elem_update(const void *key, const void *value,
 
 long per_cpu_array_map_impl::elem_delete(const void *key)
 {
-	errno = ENOTSUP;
+	errno = EINVAL;
 	SPDLOG_DEBUG("Deleting of per cpu array is not supported");
 	return -1;
 }
 
-int per_cpu_array_map_impl::map_get_next_key(const void *key,
-						 void *next_key)
+int per_cpu_array_map_impl::map_get_next_key(const void *key, void *next_key)
 {
 	// Not found
 	if (key == nullptr || *(uint32_t *)key >= max_ent) {
@@ -100,7 +106,7 @@ void *per_cpu_array_map_impl::elem_lookup_userspace(const void *key)
 	}
 	uint32_t key_val = *(uint32_t *)key;
 	if (key_val >= max_ent) {
-		errno = E2BIG;
+		errno = ENOENT;
 		return nullptr;
 	}
 	return data_at(key_val, 0);
@@ -110,11 +116,17 @@ long per_cpu_array_map_impl::elem_update_userspace(const void *key,
 						   const void *value,
 						   uint64_t flags)
 {
+	if (!check_update_flags(flags))
+		return -1;
 	if (key == nullptr) {
 		errno = ENOENT;
 		return -1;
 	}
 	uint32_t key_val = *(uint32_t *)key;
+	if (key_val < max_ent && flags == BPF_NOEXIST) {
+		errno = EEXIST;
+		return -1;
+	}
 	if (key_val >= max_ent) {
 		errno = E2BIG;
 		return -1;
@@ -126,7 +138,7 @@ long per_cpu_array_map_impl::elem_update_userspace(const void *key,
 
 long per_cpu_array_map_impl::elem_delete_userspace(const void *key)
 {
-	errno = ENOTSUP;
+	errno = EINVAL;
 	SPDLOG_ERROR("Element delete is not supported by per cpu array");
 	return -1;
 }

runtime/unit-test/maps/kernel_unit_tests.cpp

@@ -1,4 +1,5 @@
 #include "bpf_map/userspace/array_map.hpp"
+#include "bpf_map/userspace/per_cpu_array_map.hpp"
 #include "bpf_map/userspace/per_cpu_hash_map.hpp"
 #include "catch2/catch_test_macros.hpp"
 #include "linux/bpf.h"
@@ -375,3 +376,62 @@ TEST_CASE("test_arraymap (kernel)")
 	key = 1;
 	REQUIRE((map.elem_delete(&key) < 0 && errno == EINVAL));
 }
+
+TEST_CASE("test_arraymap_percpu (kernel)")
+{
+	shm_remove remover(SHM_NAME);
+	managed_shared_memory mem(boost::interprocess::create_only, SHM_NAME,
+				  20 << 20);
+	unsigned int nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+	BPF_DECLARE_PERCPU(long, values);
+	int key, next_key, i;
+	per_cpu_array_map_impl map(mem, sizeof(bpf_percpu(values, 0)), 2);
+	const auto lookup_helper = [&](const void *key, void *value) -> long {
+		auto returned_value = map.elem_lookup_userspace(key);
+		if (!returned_value)
+			return -1;
+		memcpy(value, returned_value, sizeof(values));
+		return 0;
+	};
+
+	for (i = 0; i < (int)nr_cpus; i++)
+		bpf_percpu(values, i) = i + 100;
+
+	key = 1;
+	/* Insert key=1 element. */
+	REQUIRE(map.elem_update_userspace(&key, values, BPF_ANY) == 0);
+
+	bpf_percpu(values, 0) = 0;
+	REQUIRE((map.elem_update_userspace(&key, values, BPF_NOEXIST) < 0 &&
+		 errno == EEXIST));
+
+	/* Check that key=1 can be found. */
+	REQUIRE((lookup_helper(&key, values) == 0 &&
+		 bpf_percpu(values, 0) == 100));
+
+	key = 0;
+	/* Check that key=0 is also found and zero initialized. */
+	REQUIRE((lookup_helper(&key, values) == 0 &&
+		 bpf_percpu(values, 0) == 0 &&
+		 bpf_percpu(values, nr_cpus - 1) == 0));
+
+	/* Check that key=2 cannot be inserted due to max_entries limit. */
+	key = 2;
+	REQUIRE((map.elem_update_userspace(&key, values, BPF_EXIST) < 0 &&
+		 errno == E2BIG));
+
+	/* Check that key = 2 doesn't exist. */
+	REQUIRE((lookup_helper(&key, values) < 0 && errno == ENOENT));
+
+	/* Iterate over two elements. */
+	REQUIRE((map.map_get_next_key(NULL, &next_key) == 0 && next_key == 0));
+	REQUIRE((map.map_get_next_key(&key, &next_key) == 0 && next_key == 0));
+	REQUIRE((map.map_get_next_key(&next_key, &next_key) == 0 &&
+		 next_key == 1));
+	REQUIRE((map.map_get_next_key(&next_key, &next_key) < 0 &&
+		 errno == ENOENT));
+
+	/* Delete shouldn't succeed. */
+	key = 1;
+	REQUIRE((map.elem_delete_userspace(&key) < 0 && errno == EINVAL));
+}