[PATCH 13/13] bpf tools: Add helper function for updating bpf maps elements

Path	csiph.com!eternal-september.org!feeder.eternal-september.org!aioe.org!bofh.it!news.nic.it!robomod
From	Arnaldo Carvalho de Melo <acme@kernel.org>
Newsgroups	linux.kernel
Subject	[PATCH 13/13] bpf tools: Add helper function for updating bpf maps elements
Date	Thu, 26 Nov 2015 21:50:01 +0100
Message-ID	<qzbEl-1Ge-7@gated-at.bofh.it> (permalink)
References	<qzbEl-1Ge-5@gated-at.bofh.it>
X-Original-To	Ingo Molnar <mingo@kernel.org>
X-Mailer	git-send-email 2.1.0
X-Srs-Rewrite	SMTP reverse-path rewritten from <acme@infradead.org> by casper.infradead.org See http://www.infradead.org/rpr.html
Sender	robomod@news.nic.it
List-ID	<linux-kernel.vger.kernel.org>
X-Mailing-List	linux-kernel@vger.kernel.org
Approved	robomod@news.nic.it
Lines	62
Organization	linux.* mail to news gateway
X-Original-Cc	linux-kernel@vger.kernel.org, He Kuang <hekuang@huawei.com>, Alexei Starovoitov <ast@kernel.org>, Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>, Namhyung Kim <namhyung@kernel.org>, Wang Nan <wangnan0@huawei.com>, Zefan Li <lizefan@huawei.com>, pi3orama@163.com, Arnaldo Carvalho de Melo <acme@redhat.com>
X-Original-Date	Thu, 26 Nov 2015 17:46:11 -0300
X-Original-Message-ID	<1448570771-5430-14-git-send-email-acme@kernel.org>
X-Original-References	<1448570771-5430-1-git-send-email-acme@kernel.org>
X-Original-Sender	linux-kernel-owner@vger.kernel.org
Xref	csiph.com linux.kernel:1278433

Show key headers only | View raw

From: He Kuang <hekuang@huawei.com>

Add bpf_map_update_elem() helper function which calls the sys_bpf
syscall to update elements in bpf maps. Upcoming patches will use it to
adjust data in map through the perf command line.

Signed-off-by: He Kuang <hekuang@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1448372181-151723-4-git-send-email-wangnan0@huawei.com
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/lib/bpf/bpf.c | 14 ++++++++++++++
 tools/lib/bpf/bpf.h |  2 ++
 2 files changed, 16 insertions(+)

diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index a6331050ab79..5bdc6eab6852 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -83,3 +83,17 @@ int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns,
 	log_buf[0] = 0;
 	return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
 }
+
+int bpf_map_update_elem(int fd, void *key, void *value,
+			u64 flags)
+{
+	union bpf_attr attr;
+
+	bzero(&attr, sizeof(attr));
+	attr.map_fd = fd;
+	attr.key = ptr_to_u64(key);
+	attr.value = ptr_to_u64(value);
+	attr.flags = flags;
+
+	return sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
+}
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 854b7361b784..a76465541292 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -20,4 +20,6 @@ int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns,
 		     u32 kern_version, char *log_buf,
 		     size_t log_buf_sz);
 
+int bpf_map_update_elem(int fd, void *key, void *value,
+			u64 flags);
 #endif
-- 
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next | Find similar | Unroll thread

Thread

[PATCH 13/13] bpf tools: Add helper function for updating bpf maps elements Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-11-26 21:50 +0100

csiph-web