On Thu, May 8, 2025 at 5:28 PM Song Liu song@kernel.org wrote:
On Thu, May 8, 2025 at 11:20 AM T.J. Mercier tjmercier@google.com wrote:
This open coded iterator allows for more flexibility when creating BPF programs. It can support output in formats other than text. With an open coded iterator, a single BPF program can traverse multiple kernel data structures (now including dmabufs), allowing for more efficient analysis of kernel data compared to multiple reads from procfs, sysfs, or multiple traditional BPF iterator invocations.
Signed-off-by: T.J. Mercier tjmercier@google.com
Acked-by: Song Liu song@kernel.org
With one nitpick below:
kernel/bpf/dmabuf_iter.c | 47 ++++++++++++++++++++++++++++++++++++++++ kernel/bpf/helpers.c | 5 +++++ 2 files changed, 52 insertions(+)
diff --git a/kernel/bpf/dmabuf_iter.c b/kernel/bpf/dmabuf_iter.c index 96b4ba7f0b2c..8049bdbc9efc 100644 --- a/kernel/bpf/dmabuf_iter.c +++ b/kernel/bpf/dmabuf_iter.c @@ -100,3 +100,50 @@ static int __init dmabuf_iter_init(void) }
late_initcall(dmabuf_iter_init);
+struct bpf_iter_dmabuf {
/* opaque iterator state; having __u64 here allows to preserve correct* alignment requirements in vmlinux.h, generated from BTF*/nit: comment style.
Added a leading /*
(This is copied from task_iter.c, which currently has the same style.)
__u64 __opaque[1];+} __aligned(8);
+/* Non-opaque version of bpf_iter_dmabuf */ +struct bpf_iter_dmabuf_kern {
struct dma_buf *dmabuf;+} __aligned(8);
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