From: Brian Vazquez <brianvv@google.com>
To: Brian Vazquez <brianvv.kernel@gmail.com>,
Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
"David S . Miller" <davem@davemloft.net>
Cc: Stanislav Fomichev <sdf@google.com>,
Willem de Bruijn <willemb@google.com>,
Petar Penkov <ppenkov@google.com>,
linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
bpf@vger.kernel.org, Brian Vazquez <brianvv@google.com>
Subject: [RFC PATCH bpf-next v2 0/6] bpf: add BPF_MAP_DUMP command to
Date: Thu, 27 Jun 2019 13:24:11 -0700 [thread overview]
Message-ID: <20190627202417.33370-1-brianvv@google.com> (raw)
This introduces a new command to retrieve a variable number of entries
from a bpf map.
This new command can be executed from the existing BPF syscall as
follows:
err = bpf(BPF_MAP_DUMP, union bpf_attr *attr, u32 size)
using attr->dump.map_fd, attr->dump.prev_key, attr->dump.buf,
attr->dump.buf_len
returns zero or negative error, and populates buf and buf_len on
succees
This implementation is wrapping the existing bpf methods:
map_get_next_key and map_lookup_elem
the results show that even with a 1-elem_size buffer, it runs ~40 faster
than the current implementation, improvements of ~85% are reported when
the buffer size is increased, although, after the buffer size is around
5% of the total number of entries there's no huge difference in
increasing
it.
Tested:
Tried different size buffers to handle case where the bulk is bigger, or
the elements to retrieve are less than the existing ones, all runs read
a map of 100K entries. Below are the results(in ns) from the different
runs:
buf_len_1: 55528939 entry-by-entry: 97244981 improvement
42.897887%
buf_len_2: 34425779 entry-by-entry: 88863122 improvement
61.259769%
buf_len_230: 11700316 entry-by-entry: 88753301 improvement
86.817036%
buf_len_5000: 11615290 entry-by-entry: 88362637 improvement
86.854976%
buf_len_73000: 12083976 entry-by-entry: 89956483 improvement
86.566865%
buf_len_100000: 12638913 entry-by-entry: 89642303 improvement
85.900727%
buf_len_234567: 11873964 entry-by-entry: 89080077 improvement
86.670461%
Changelog:
v2:
- use proper bpf-next tag
Brian Vazquez (6):
bpf: add bpf_map_value_size and bp_map_copy_value helper functions
bpf: add BPF_MAP_DUMP command to access more than one entry per call
bpf: keep bpf.h in sync with tools/
libbpf: support BPF_MAP_DUMP command
selftests/bpf: test BPF_MAP_DUMP command on a bpf hashmap
selftests/bpf: add test to measure performance of BPF_MAP_DUMP
include/uapi/linux/bpf.h | 9 +
kernel/bpf/syscall.c | 242 ++++++++++++++++++------
tools/include/uapi/linux/bpf.h | 9 +
tools/lib/bpf/bpf.c | 28 +++
tools/lib/bpf/bpf.h | 4 +
tools/lib/bpf/libbpf.map | 2 +
tools/testing/selftests/bpf/test_maps.c | 141 +++++++++++++-
7 files changed, 372 insertions(+), 63 deletions(-)
--
2.22.0.410.gd8fdbe21b5-goog
next reply other threads:[~2019-06-27 20:24 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-27 20:24 Brian Vazquez [this message]
2019-06-27 20:24 ` [RFC PATCH bpf-next v2 1/6] bpf: add bpf_map_value_size and bp_map_copy_value helper functions Brian Vazquez
2019-06-27 20:24 ` [RFC PATCH bpf-next v2 2/6] bpf: add BPF_MAP_DUMP command to access more than one entry per call Brian Vazquez
2019-06-27 22:12 ` Alexei Starovoitov
2019-06-28 17:49 ` Brian Vazquez
2019-06-27 20:24 ` [RFC PATCH bpf-next v2 3/6] bpf: keep bpf.h in sync with tools/ Brian Vazquez
2019-06-27 20:24 ` [RFC PATCH bpf-next v2 4/6] libbpf: support BPF_MAP_DUMP command Brian Vazquez
2019-06-27 20:24 ` [RFC PATCH bpf-next v2 5/6] selftests/bpf: test BPF_MAP_DUMP command on a bpf hashmap Brian Vazquez
2019-06-27 20:24 ` [RFC PATCH bpf-next v2 6/6] selftests/bpf: add test to measure performance of BPF_MAP_DUMP Brian Vazquez
2019-06-27 22:14 ` [RFC PATCH bpf-next v2 0/6] bpf: add BPF_MAP_DUMP command to Alexei Starovoitov
2019-06-28 17:50 ` Brian Vazquez
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