From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753899AbbDBMgZ (ORCPT ); Thu, 2 Apr 2015 08:36:25 -0400 Received: from terminus.zytor.com ([198.137.202.10]:60925 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752187AbbDBMgU (ORCPT ); Thu, 2 Apr 2015 08:36:20 -0400 Date: Thu, 2 Apr 2015 05:35:24 -0700 From: tip-bot for Alexei Starovoitov Message-ID: Cc: jolsa@redhat.com, acme@redhat.com, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, davem@davemloft.net, namhyung@kernel.org, masami.hiramatsu.pt@hitachi.com, mingo@kernel.org, a.p.zijlstra@chello.nl, peterz@infradead.org, daniel@iogearbox.net, hpa@zytor.com, akpm@linux-foundation.org, acme@infradead.org, ast@plumgrid.com, rostedt@goodmis.org Reply-To: rostedt@goodmis.org, ast@plumgrid.com, acme@infradead.org, akpm@linux-foundation.org, hpa@zytor.com, daniel@iogearbox.net, peterz@infradead.org, a.p.zijlstra@chello.nl, mingo@kernel.org, davem@davemloft.net, namhyung@kernel.org, masami.hiramatsu.pt@hitachi.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, jolsa@redhat.com, acme@redhat.com, torvalds@linux-foundation.org In-Reply-To: <1427312966-8434-5-git-send-email-ast@plumgrid.com> References: <1427312966-8434-5-git-send-email-ast@plumgrid.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] tracing: Allow BPF programs to call bpf_ktime_get_ns() Git-Commit-ID: d9847d310ab4003725e6ed1822682e24bd406908 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: d9847d310ab4003725e6ed1822682e24bd406908 Gitweb: http://git.kernel.org/tip/d9847d310ab4003725e6ed1822682e24bd406908 Author: Alexei Starovoitov AuthorDate: Wed, 25 Mar 2015 12:49:21 -0700 Committer: Ingo Molnar CommitDate: Thu, 2 Apr 2015 13:25:49 +0200 tracing: Allow BPF programs to call bpf_ktime_get_ns() bpf_ktime_get_ns() is used by programs to compute time delta between events or as a timestamp Signed-off-by: Alexei Starovoitov Reviewed-by: Steven Rostedt Cc: Andrew Morton Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Daniel Borkmann Cc: David S. Miller Cc: Jiri Olsa Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1427312966-8434-5-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar --- include/uapi/linux/bpf.h | 1 + kernel/trace/bpf_trace.c | 14 ++++++++++++++ 2 files changed, 15 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index b2948fe..238c688 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -165,6 +165,7 @@ enum bpf_func_id { BPF_FUNC_map_update_elem, /* int map_update_elem(&map, &key, &value, flags) */ BPF_FUNC_map_delete_elem, /* int map_delete_elem(&map, &key) */ BPF_FUNC_probe_read, /* int bpf_probe_read(void *dst, int size, void *src) */ + BPF_FUNC_ktime_get_ns, /* u64 bpf_ktime_get_ns(void) */ __BPF_FUNC_MAX_ID, }; diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index f1e87da..8f57872 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -78,6 +78,18 @@ static const struct bpf_func_proto bpf_probe_read_proto = { .arg3_type = ARG_ANYTHING, }; +static u64 bpf_ktime_get_ns(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) +{ + /* NMI safe access to clock monotonic */ + return ktime_get_mono_fast_ns(); +} + +static const struct bpf_func_proto bpf_ktime_get_ns_proto = { + .func = bpf_ktime_get_ns, + .gpl_only = true, + .ret_type = RET_INTEGER, +}; + static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func_id) { switch (func_id) { @@ -89,6 +101,8 @@ static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func return &bpf_map_delete_elem_proto; case BPF_FUNC_probe_read: return &bpf_probe_read_proto; + case BPF_FUNC_ktime_get_ns: + return &bpf_ktime_get_ns_proto; default: return NULL; }