[PATCH bpf-next 03/17] bpf: Document BPF_F_LOCK in syscall commands
From: Joe Stringer <hidden>
Date: 2021-02-17 01:09:30
Also in:
bpf
Subsystem:
bpf [general] (safe dynamic programs and tools), the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds
From: Joe Stringer <redacted>
Document the meaning of the BPF_F_LOCK flag for the map lookup/update
descriptions. Based on commit 96049f3afd50 ("bpf: introduce BPF_F_LOCK
flag").
Reviewed-by: Quentin Monnet <redacted>
Signed-off-by: Joe Stringer <redacted>
---
CC: Alexei Starovoitov <ast@kernel.org>
---
include/uapi/linux/bpf.h | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index ac6880d7b01b..d02259458fd6 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h@@ -120,6 +120,14 @@ union bpf_iter_link_info { * Look up an element with a given *key* in the map referred to * by the file descriptor *map_fd*. * + * The *flags* argument may be specified as one of the + * following: + * + * **BPF_F_LOCK** + * Look up the value of a spin-locked map without + * returning the lock. This must be specified if the + * elements contain a spinlock. + * * Return * Returns zero on success. On error, -1 is returned and *errno* * is set appropriately.
@@ -137,6 +145,8 @@ union bpf_iter_link_info { * Create a new element only if it did not exist. * **BPF_EXIST** * Update an existing element. + * **BPF_F_LOCK** + * Update a spin_lock-ed map element. * * Return * Returns zero on success. On error, -1 is returned and *errno*
--
2.27.0