Added four libbpf API functions to support map batch operations:
. int bpf_map_delete_batch( ... )
. int bpf_map_lookup_batch( ... )
. int bpf_map_lookup_and_delete_batch( ... )
. int bpf_map_update_batch( ... )
Tested bpf_map_lookup_and_delete_batch() and bpf_map_update_batch()
functionality.
$ ./test_maps
...
test_map_lookup_and_delete_batch:PASS
...
Note that I clumped uapi header sync patch, libbpf patch
and tests patch together considering this is a RFC patch.
Will do proper formating once it is out of RFC stage.
Signed-off-by: Yonghong Song <y...@fb.com>
---
tools/include/uapi/linux/bpf.h | 22 +++
tools/lib/bpf/bpf.c | 59 +++++++
tools/lib/bpf/bpf.h | 13 ++
tools/lib/bpf/libbpf.map | 4 +
.../map_tests/map_lookup_and_delete_batch.c | 155 ++++++++++++++++++
5 files changed, 253 insertions(+)
create mode 100644
tools/testing/selftests/bpf/map_tests/map_lookup_and_delete_batch.c
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 5d2fb183ee2d..9d4f76073dd9 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -107,6 +107,10 @@ enum bpf_cmd {
BPF_MAP_LOOKUP_AND_DELETE_ELEM,
BPF_MAP_FREEZE,
BPF_BTF_GET_NEXT_ID,
+ BPF_MAP_LOOKUP_BATCH,
+ BPF_MAP_LOOKUP_AND_DELETE_BATCH,
+ BPF_MAP_UPDATE_BATCH,
+ BPF_MAP_DELETE_BATCH,
};
enum bpf_map_type {
@@ -396,6 +400,24 @@ union bpf_attr {
__u64 flags;
};
+ struct { /* struct used by BPF_MAP_*_BATCH commands */
+ __u64 batch; /* input/output:
+ * input: start batch,
+ * 0 to start from beginning.
+ * output: next start batch,
+ * 0 to end batching.
+ */
+ __aligned_u64 keys;
+ __aligned_u64 values;
+ __u32 count; /* input/output:
+ * input: # of elements keys/values.
+ * output: # of filled elements.
+ */
+ __u32 map_fd;
+ __u64 elem_flags;
+ __u64 flags;
+ } batch;
+
struct { /* anonymous struct used by BPF_PROG_LOAD command */
__u32 prog_type; /* one of enum bpf_prog_type */
__u32 insn_cnt;
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index cbb933532981..367bdcb3c62b 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -438,6 +438,65 @@ int bpf_map_freeze(int fd)
return sys_bpf(BPF_MAP_FREEZE, &attr, sizeof(attr));
}
+static int bpf_map_batch_common(int cmd, int fd, __u64 *batch,
+ void *keys, void *values,
+ __u32 *count, __u64 elem_flags,
+ __u64 flags)
+{
+ union bpf_attr attr = {};
+ int ret;
+
+ attr.batch.map_fd = fd;
+ if (batch)
+ attr.batch.batch = *batch;
+ attr.batch.keys = ptr_to_u64(keys);
+ attr.batch.values = ptr_to_u64(values);
+ if (count)
+ attr.batch.count = *count;
+ attr.batch.elem_flags = elem_flags;
+ attr.batch.flags = flags;
+
+ ret = sys_bpf(cmd, &attr, sizeof(attr));
+ if (batch)
+ *batch = attr.batch.batch;
+ if (count)
+ *count = attr.batch.count;
+
+ return ret;
+}
+
+int bpf_map_delete_batch(int fd, __u64 *batch, __u32 *count, __u64 elem_flags,
+ __u64 flags)
+{
+ return bpf_map_batch_common(BPF_MAP_DELETE_BATCH, fd, batch,
+ NULL, NULL, count, elem_flags, flags);
+}
+
+int bpf_map_lookup_batch(int fd, __u64 *batch, void *keys, void *values,
+ __u32 *count, __u64 elem_flags, __u64 flags)
+{
+ return bpf_map_batch_common(BPF_MAP_LOOKUP_BATCH, fd, batch,
+ keys, values, count, elem_flags, flags);
+}
+
+int bpf_map_lookup_and_delete_batch(int fd, __u64 *batch,
+ void *keys, void *values,
+ __u32 *count, __u64 elem_flags,
+ __u64 flags)
+{
+ return bpf_map_batch_common(BPF_MAP_LOOKUP_AND_DELETE_BATCH,
+ fd, batch, keys, values,
+ count, elem_flags, flags);
+}
+
+int bpf_map_update_batch(int fd, void *keys, void *values, __u32 *count,
+ __u64 elem_flags, __u64 flags)
+{
+ return bpf_map_batch_common(BPF_MAP_UPDATE_BATCH,
+ fd, NULL, keys, values,
+ count, elem_flags, flags);
+}
+
int bpf_obj_pin(int fd, const char *pathname)
{
union bpf_attr attr;
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 0db01334740f..37211840f345 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -120,6 +120,19 @@ LIBBPF_API int bpf_map_lookup_and_delete_elem(int fd,
const void *key,
LIBBPF_API int bpf_map_delete_elem(int fd, const void *key);
LIBBPF_API int bpf_map_get_next_key(int fd, const void *key, void *next_key);
LIBBPF_API int bpf_map_freeze(int fd);
+LIBBPF_API int bpf_map_delete_batch(int fd, __u64 *batch, __u32 *count,
+ __u64 elem_flags, __u64 flags);
+LIBBPF_API int bpf_map_lookup_batch(int fd, __u64 *batch, void *keys,
+ void *values, __u32 *count,
+ __u64 elem_flags, __u64 flags);
+LIBBPF_API int bpf_map_lookup_and_delete_batch(int fd, __u64 *batch,
+ void *keys, void *values,
+ __u32 *count, __u64 elem_flags,
+ __u64 flags);
+LIBBPF_API int bpf_map_update_batch(int fd, void *keys, void *values,
+ __u32 *count, __u64 elem_flags,
+ __u64 flags);
+
LIBBPF_API int bpf_obj_pin(int fd, const char *pathname);
LIBBPF_API int bpf_obj_get(const char *pathname);
LIBBPF_API int bpf_prog_attach(int prog_fd, int attachable_fd,
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index d04c7cb623ed..739bd9f76e50 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -189,4 +189,8 @@ LIBBPF_0.0.4 {
LIBBPF_0.0.5 {
global:
bpf_btf_get_next_id;
+ bpf_map_delete_batch;
+ bpf_map_lookup_and_delete_batch;
+ bpf_map_lookup_batch;
+ bpf_map_update_batch;
} LIBBPF_0.0.4;
diff --git
a/tools/testing/selftests/bpf/map_tests/map_lookup_and_delete_batch.c
b/tools/testing/selftests/bpf/map_tests/map_lookup_and_delete_batch.c
new file mode 100644
index 000000000000..dd906b1de595
--- /dev/null
+++ b/tools/testing/selftests/bpf/map_tests/map_lookup_and_delete_batch.c
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Facebook */
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#include <test_maps.h>
+
+static void map_batch_update(int map_fd, __u32 max_entries, int *keys,
+ int *values)
+{
+ int i, err;
+
+ for (i = 0; i < max_entries; i++) {
+ keys[i] = i + 1;
+ values[i] = i + 2;
+ }
+
+ err = bpf_map_update_batch(map_fd, keys, values, &max_entries, 0, 0);
+ CHECK(err, "bpf_map_update_batch()", "error:%s\n", strerror(errno));
+}
+
+static void map_batch_verify(int *visited, __u32 max_entries,
+ int *keys, int *values)
+{
+ int i;
+
+ memset(visited, 0, max_entries * sizeof(*visited));
+ for (i = 0; i < max_entries; i++) {
+ CHECK(keys[i] + 1 != values[i], "key/value checking",
+ "error: i %d key %d value %d\n", i, keys[i], values[i]);
+ visited[i] = 1;
+ }
+ for (i = 0; i < max_entries; i++) {
+ CHECK(visited[i] != 1, "visited checking",
+ "error: keys array at index %d missing\n", i);
+ }
+}
+
+void test_map_lookup_and_delete_batch(void)
+{
+ struct bpf_create_map_attr xattr = {
+ .name = "hash_map",
+ .map_type = BPF_MAP_TYPE_HASH,
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ };
+ int map_fd, *keys, *values, *visited, key;
+ __u32 count, total, total_success;
+ const __u32 max_entries = 10;
+ int err, i, step;
+ bool nospace_err;
+ __u64 batch = 0;
+
+ xattr.max_entries = max_entries;
+ map_fd = bpf_create_map_xattr(&xattr);
+ CHECK(map_fd == -1,
+ "bpf_create_map_xattr()", "error:%s\n", strerror(errno));
+
+ keys = malloc(max_entries * sizeof(int));
+ values = malloc(max_entries * sizeof(int));
+ visited = malloc(max_entries * sizeof(int));
+ CHECK(!keys || !values || !visited, "malloc()", "error:%s\n",
strerror(errno));
+
+ /* test 1: lookup/delete an empty hash table, success */
+ count = max_entries;
+ err = bpf_map_lookup_and_delete_batch(map_fd, &batch, keys, values,
+ &count, 0, 0);
+ CHECK(err, "empty map", "error: %s\n", strerror(errno));
+ CHECK(batch || count, "empty map", "batch = %lld, count = %u\n", batch,
count);
+
+ /* populate elements to the map */
+ map_batch_update(map_fd, max_entries, keys, values);
+
+ /* test 2: lookup/delete with count = 0, success */
+ batch = 0;
+ count = 0;
+ err = bpf_map_lookup_and_delete_batch(map_fd, &batch, keys, values,
+ &count, 0, 0);
+ CHECK(err, "count = 0", "error: %s\n", strerror(errno));
+
+ /* test 3: lookup/delete with count = max_entries, success */
+ memset(keys, 0, max_entries * sizeof(*keys));
+ memset(values, 0, max_entries * sizeof(*values));
+ count = max_entries;
+ batch = 0;
+ err = bpf_map_lookup_and_delete_batch(map_fd, &batch, keys,
+ values, &count, 0, 0);
+ CHECK(err, "count = max_entries", "error: %s\n", strerror(errno));
+ CHECK(count != max_entries || batch != 0, "count = max_entries",
+ "count = %u, max_entries = %u, batch = %lld\n",
+ count, max_entries, batch);
+ map_batch_verify(visited, max_entries, keys, values);
+
+ /* bpf_map_get_next_key() should return -ENOENT for an empty map. */
+ err = bpf_map_get_next_key(map_fd, NULL, &key);
+ CHECK(!err, "bpf_map_get_next_key()", "error: %s\n", strerror(errno));
+
+ /* test 4: lookup/delete in a loop with various steps. */
+ total_success = 0;
+ for (step = 1; step < max_entries; step++) {
+ map_batch_update(map_fd, max_entries, keys, values);
+ memset(keys, 0, max_entries * sizeof(*keys));
+ memset(values, 0, max_entries * sizeof(*values));
+ batch = 0;
+ total = 0;
+ i = 0;
+ /* iteratively lookup/delete elements with 'step' elements each
*/
+ count = step;
+ nospace_err = false;
+ while (true) {
+ err = bpf_map_lookup_and_delete_batch(map_fd, &batch,
+ keys + total,
+ values + total,
+ &count, 0, 0);
+ /* It is possible that we are failing due to buffer size
+ * not big enough. In such cases, let us just exit and
+ * go with large steps. Not that a buffer size with
+ * max_entries should always work.
+ */
+ if (err && errno == ENOSPC) {
+ nospace_err = true;
+ break;
+ }
+
+ CHECK(err, "lookup/delete with steps", "error: %s\n",
+ strerror(errno));
+
+ total += count;
+ if (batch == 0)
+ break;
+
+ i++;
+ }
+
+ if (nospace_err == true)
+ continue;
+
+ CHECK(total != max_entries, "lookup/delete with steps",
+ "total = %u, max_entries = %u\n", total, max_entries);
+
+ map_batch_verify(visited, max_entries, keys, values);
+ err = bpf_map_get_next_key(map_fd, NULL, &key);
+ CHECK(!err, "bpf_map_get_next_key()", "error: %s\n",
strerror(errno));
+
+ total_success++;
+ }
+
+ CHECK(total_success == 0, "check total_success", "unexpected
failure\n");
+
+ printf("%s:PASS\n", __func__);
+}
--
2.17.1
