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authorDonald Hunter <donald.hunter@gmail.com>2022-11-22 17:39:33 +0300
committerDaniel Borkmann <daniel@iogearbox.net>2022-11-24 03:05:04 +0300
commit539886a32a6a4601241d928dc8b776b052c04ed0 (patch)
tree8fdf2de8f0c6dcd04be2d6b2f222136e5d48d740 /Documentation/bpf/map_hash.rst
parent8e898aaa733eca61393fc036c8a4b5834fee5dd3 (diff)
downloadlinux-539886a32a6a4601241d928dc8b776b052c04ed0.tar.xz
docs/bpf: Fix sphinx warnings in BPF map docs
Fix duplicate C declaration warnings when using sphinx >= 3.1. Reported-by: Akira Yokosawa <akiyks@gmail.com> Signed-off-by: Donald Hunter <donald.hunter@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Akira Yokosawa <akiyks@gmail.com> Link: https://lore.kernel.org/bpf/ed4dac84-1b12-5c58-e4de-93ab9ac67c09@gmail.com Link: https://lore.kernel.org/bpf/20221122143933.91321-1-donald.hunter@gmail.com
Diffstat (limited to 'Documentation/bpf/map_hash.rst')
-rw-r--r--Documentation/bpf/map_hash.rst33
1 files changed, 28 insertions, 5 deletions
diff --git a/Documentation/bpf/map_hash.rst b/Documentation/bpf/map_hash.rst
index e85120878b27..8669426264c6 100644
--- a/Documentation/bpf/map_hash.rst
+++ b/Documentation/bpf/map_hash.rst
@@ -34,7 +34,14 @@ the ``BPF_F_NO_COMMON_LRU`` flag when calling ``bpf_map_create``.
Usage
=====
-.. c:function::
+Kernel BPF
+----------
+
+bpf_map_update_elem()
+~~~~~~~~~~~~~~~~~~~~~
+
+.. code-block:: c
+
long bpf_map_update_elem(struct bpf_map *map, const void *key, const void *value, u64 flags)
Hash entries can be added or updated using the ``bpf_map_update_elem()``
@@ -49,14 +56,22 @@ parameter can be used to control the update behaviour:
``bpf_map_update_elem()`` returns 0 on success, or negative error in
case of failure.
-.. c:function::
+bpf_map_lookup_elem()
+~~~~~~~~~~~~~~~~~~~~~
+
+.. code-block:: c
+
void *bpf_map_lookup_elem(struct bpf_map *map, const void *key)
Hash entries can be retrieved using the ``bpf_map_lookup_elem()``
helper. This helper returns a pointer to the value associated with
``key``, or ``NULL`` if no entry was found.
-.. c:function::
+bpf_map_delete_elem()
+~~~~~~~~~~~~~~~~~~~~~
+
+.. code-block:: c
+
long bpf_map_delete_elem(struct bpf_map *map, const void *key)
Hash entries can be deleted using the ``bpf_map_delete_elem()``
@@ -70,7 +85,11 @@ For ``BPF_MAP_TYPE_PERCPU_HASH`` and ``BPF_MAP_TYPE_LRU_PERCPU_HASH``
the ``bpf_map_update_elem()`` and ``bpf_map_lookup_elem()`` helpers
automatically access the hash slot for the current CPU.
-.. c:function::
+bpf_map_lookup_percpu_elem()
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. code-block:: c
+
void *bpf_map_lookup_percpu_elem(struct bpf_map *map, const void *key, u32 cpu)
The ``bpf_map_lookup_percpu_elem()`` helper can be used to lookup the
@@ -89,7 +108,11 @@ See ``tools/testing/selftests/bpf/progs/test_spin_lock.c``.
Userspace
---------
-.. c:function::
+bpf_map_get_next_key()
+~~~~~~~~~~~~~~~~~~~~~~
+
+.. code-block:: c
+
int bpf_map_get_next_key(int fd, const void *cur_key, void *next_key)
In userspace, it is possible to iterate through the keys of a hash using