diff options
| author | Tero Kristo <tero.kristo@linux.intel.com> | 2023-03-02 12:46:13 +0100 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2023-03-03 07:41:32 +0100 |
| commit | f71f8530494bb5ab43d3369ef0ce8373eb1ee077 (patch) | |
| tree | de62a9ddb2781c29925cda8028ef1fb17573dbc5 /tools/include | |
| parent | selftests/bpf: Add -Wuninitialized flag to bpf prog flags (diff) | |
| download | linux-f71f8530494bb5ab43d3369ef0ce8373eb1ee077.tar.xz linux-f71f8530494bb5ab43d3369ef0ce8373eb1ee077.zip | |
bpf: Add support for absolute value BPF timers
Add a new flag BPF_F_TIMER_ABS that can be passed to bpf_timer_start()
to start an absolute value timer instead of the default relative value.
This makes the timer expire at an exact point in time, instead of a time
with latencies induced by both the BPF and timer subsystems.
Suggested-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Tero Kristo <tero.kristo@linux.intel.com>
Link: https://lore.kernel.org/r/20230302114614.2985072-2-tero.kristo@linux.intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/include')
| -rw-r--r-- | tools/include/uapi/linux/bpf.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index c9699304aed2..976b194eb775 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -4969,6 +4969,12 @@ union bpf_attr { * different maps if key/value layout matches across maps. * Every bpf_timer_set_callback() can have different callback_fn. * + * *flags* can be one of: + * + * **BPF_F_TIMER_ABS** + * Start the timer in absolute expire value instead of the + * default relative one. + * * Return * 0 on success. * **-EINVAL** if *timer* was not initialized with bpf_timer_init() earlier @@ -7097,4 +7103,13 @@ struct bpf_core_relo { enum bpf_core_relo_kind kind; }; +/* + * Flags to control bpf_timer_start() behaviour. + * - BPF_F_TIMER_ABS: Timeout passed is absolute time, by default it is + * relative to current time. + */ +enum { + BPF_F_TIMER_ABS = (1ULL << 0), +}; + #endif /* _UAPI__LINUX_BPF_H__ */ |