kernel/linux.git/tools/lib/bpf/ringbuf.c, branch v6.12.80

libbpf: fix ring_buffer__consume_n() return result logic

2024-05-02T23:41:03+00:00

Add INT_MAX check to ring_buffer__consume_n(). We do the similar check to handle int return result of all these ring buffer APIs in other APIs and ring_buffer__consume_n() is missing one. This patch fixes this omission. Signed-off-by: Andrii Nakryiko Acked-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20240430201952.888293-2-andrii@kernel.org Signed-off-by: Martin KaFai Lau

libbpf: fix potential overflow in ring__consume_n()

2024-05-02T23:41:02+00:00

ringbuf_process_ring() return int64_t, while ring__consume_n() assigns it to int. It's highly unlikely, but possible for ringbuf_process_ring() to return value larger than INT_MAX, so use int64_t. ring__consume_n() does check INT_MAX before returning int result to the user. Fixes: 4d22ea94ea33 ("libbpf: Add ring__consume_n / ring_buffer__consume_n") Signed-off-by: Andrii Nakryiko Acked-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20240430201952.888293-1-andrii@kernel.org Signed-off-by: Martin KaFai Lau

libbpf: Add ring__consume_n / ring_buffer__consume_n

2024-04-06T16:11:55+00:00

Introduce a new API to consume items from a ring buffer, limited to a specified amount, and return to the caller the actual number of items consumed. Signed-off-by: Andrea Righi Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/lkml/20240310154726.734289-1-andrea.righi@canonical.com/T Link: https://lore.kernel.org/bpf/20240406092005.92399-4-andrea.righi@canonical.com

libbpf: ringbuf: Allow to consume up to a certain amount of items

2024-04-06T16:11:54+00:00

In some cases, instead of always consuming all items from ring buffers in a greedy way, we may want to consume up to a certain amount of items, for example when we need to copy items from the BPF ring buffer to a limited user buffer. This change allows to set an upper limit to the amount of items consumed from one or more ring buffers. Signed-off-by: Andrea Righi Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20240406092005.92399-3-andrea.righi@canonical.com

libbpf: Add ring__consume

2023-09-25T23:22:43+00:00

Add ring__consume to consume a single ringbuffer, analogous to ring_buffer__consume. Signed-off-by: Martin Kelly Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230925215045.2375758-14-martin.kelly@crowdstrike.com

libbpf: Add ring__map_fd

2023-09-25T23:22:43+00:00

Add ring__map_fd to get the file descriptor underlying a given ringbuffer. Signed-off-by: Martin Kelly Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230925215045.2375758-12-martin.kelly@crowdstrike.com

libbpf: Add ring__size

2023-09-25T23:22:43+00:00

Add ring__size to get the total size of a given ringbuffer. Signed-off-by: Martin Kelly Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230925215045.2375758-10-martin.kelly@crowdstrike.com

libbpf: Add ring__avail_data_size

2023-09-25T23:22:42+00:00

Add ring__avail_data_size for querying the currently available data in the ringbuffer, similar to the BPF_RB_AVAIL_DATA flag in bpf_ringbuf_query. This is racy during ongoing operations but is still useful for overall information on how a ringbuffer is behaving. Signed-off-by: Martin Kelly Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230925215045.2375758-8-martin.kelly@crowdstrike.com

libbpf: Add ring__producer_pos, ring__consumer_pos

2023-09-25T23:22:42+00:00

Add APIs to get the producer and consumer position for a given ringbuffer. Signed-off-by: Martin Kelly Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230925215045.2375758-6-martin.kelly@crowdstrike.com

libbpf: Add ring_buffer__ring

2023-09-25T23:22:42+00:00

Add a new function ring_buffer__ring, which exposes struct ring * to the user, representing a single ringbuffer. Signed-off-by: Martin Kelly Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230925215045.2375758-4-martin.kelly@crowdstrike.com