On Sat, Apr 3, 2021 at 6:34 AM Pedro Tammela pctammela@gmail.com wrote:
Em qua., 31 de mar. de 2021 às 03:54, Andrii Nakryiko andrii.nakryiko@gmail.com escreveu:
On Sun, Mar 28, 2021 at 9:11 AM Pedro Tammela pctammela@gmail.com wrote:
The current way to provide a no-op flag to 'bpf_ringbuf_submit()', 'bpf_ringbuf_discard()' and 'bpf_ringbuf_output()' is to provide a '0' value.
A '0' value might notify the consumer if it already caught up in processing, so let's provide a more descriptive notation for this value.
Signed-off-by: Pedro Tammela pctammela@mojatatu.com
flags == 0 means "no extra modifiers of behavior". That's default adaptive notification. If you want to adjust default behavior, only then you specify non-zero flags. I don't think anyone will bother typing BPF_RB_MAY_WAKEUP for this, nor I think it's really needed. The documentation update is nice (if no flags are specified notification will be sent if needed), but the new "pseudo-flag" seems like an overkill to me.
My intention here is to make '0' more descriptive. But if you think just the documentation update is enough, then I will remove the flag.
flags == 0 means "default behavior", I don't think you have to remember which verbose flag you need to specify for that, so I think just expanding documentation is sufficient and better. Thanks!
include/uapi/linux/bpf.h | 8 ++++++++ tools/include/uapi/linux/bpf.h | 8 ++++++++ tools/testing/selftests/bpf/progs/ima.c | 2 +- tools/testing/selftests/bpf/progs/ringbuf_bench.c | 2 +- tools/testing/selftests/bpf/progs/test_ringbuf.c | 2 +- tools/testing/selftests/bpf/progs/test_ringbuf_multi.c | 2 +- 6 files changed, 20 insertions(+), 4 deletions(-)
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