From: Alexei Starovoitov <ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
To: Steven Rostedt <rostedt-nx8X9YLhiw1AfugRpC6u6w@public.gmane.org>
Cc: Ingo Molnar <mingo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
Namhyung Kim <namhyung-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
Arnaldo Carvalho de Melo
<acme-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>,
Jiri Olsa <jolsa-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
Masami Hiramatsu
<masami.hiramatsu.pt-FCd8Q96Dh0JBDgjK7y7TUQ@public.gmane.org>,
"David S. Miller" <davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org>,
Daniel Borkmann <daniel-FeC+5ew28dpmcu3hnIyYJQ@public.gmane.org>,
Peter Zijlstra
<a.p.zijlstra-/NLkJaSkS4VmR6Xm/wNWPw@public.gmane.org>,
linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: [PATCH v7 tip 3/8] tracing: allow BPF programs to call bpf_ktime_get_ns()
Date: Thu, 19 Mar 2015 08:38:05 -0700 [thread overview]
Message-ID: <550AED5D.3010700@plumgrid.com> (raw)
In-Reply-To: <20150319111124.38f53061-f9ZlEuEWxVcJvu8Pb33WZ0EMvNT87kid@public.gmane.org>
On 3/19/15 8:11 AM, Steven Rostedt wrote:
> On Mon, 16 Mar 2015 14:49:39 -0700
> Alexei Starovoitov <ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org> wrote:
>
>> bpf_ktime_get_ns() is used by programs to compue time delta between events
>
> "compute"
ok :)
>> + [BPF_FUNC_ktime_get_ns] = {
>> + .func = bpf_ktime_get_ns,
>> + .gpl_only = true,
>> + .ret_type = RET_INTEGER,
>
> Hmm, a nanosecond value returned as integer? Is there a way to make
> this a 64 bit return type, or is RET_INTEGER default to 64 bits in BPF
> functions?
RET_INTEGER doesn't mean C 'int' width. It means non-pointer and
non-void value. The return value is always promoted to full
register width which is 64-bit.
WARNING: multiple messages have this Message-ID (diff)
From: Alexei Starovoitov <ast@plumgrid.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@kernel.org>,
Namhyung Kim <namhyung@kernel.org>,
Arnaldo Carvalho de Melo <acme@infradead.org>,
Jiri Olsa <jolsa@redhat.com>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
"David S. Miller" <davem@davemloft.net>,
Daniel Borkmann <daniel@iogearbox.net>,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
linux-api@vger.kernel.org, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v7 tip 3/8] tracing: allow BPF programs to call bpf_ktime_get_ns()
Date: Thu, 19 Mar 2015 08:38:05 -0700 [thread overview]
Message-ID: <550AED5D.3010700@plumgrid.com> (raw)
In-Reply-To: <20150319111124.38f53061@gandalf.local.home>
On 3/19/15 8:11 AM, Steven Rostedt wrote:
> On Mon, 16 Mar 2015 14:49:39 -0700
> Alexei Starovoitov <ast@plumgrid.com> wrote:
>
>> bpf_ktime_get_ns() is used by programs to compue time delta between events
>
> "compute"
ok :)
>> + [BPF_FUNC_ktime_get_ns] = {
>> + .func = bpf_ktime_get_ns,
>> + .gpl_only = true,
>> + .ret_type = RET_INTEGER,
>
> Hmm, a nanosecond value returned as integer? Is there a way to make
> this a 64 bit return type, or is RET_INTEGER default to 64 bits in BPF
> functions?
RET_INTEGER doesn't mean C 'int' width. It means non-pointer and
non-void value. The return value is always promoted to full
register width which is 64-bit.
next prev parent reply other threads:[~2015-03-19 15:38 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-03-16 21:49 [PATCH v7 tip 0/8] tracing: attach eBPF programs to kprobes Alexei Starovoitov
2015-03-16 21:49 ` [PATCH v7 tip 1/8] bpf: make internal bpf API independent of CONFIG_BPF_SYSCALL ifdefs Alexei Starovoitov
2015-03-16 21:49 ` [PATCH v7 tip 3/8] tracing: allow BPF programs to call bpf_ktime_get_ns() Alexei Starovoitov
[not found] ` <1426542584-9406-4-git-send-email-ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-03-19 15:11 ` Steven Rostedt
2015-03-19 15:11 ` Steven Rostedt
[not found] ` <20150319111124.38f53061-f9ZlEuEWxVcJvu8Pb33WZ0EMvNT87kid@public.gmane.org>
2015-03-19 15:38 ` Alexei Starovoitov [this message]
2015-03-19 15:38 ` Alexei Starovoitov
2015-03-19 15:41 ` Steven Rostedt
[not found] ` <1426542584-9406-1-git-send-email-ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-03-16 21:49 ` [PATCH v7 tip 2/8] tracing: attach BPF programs to kprobes Alexei Starovoitov
2015-03-16 21:49 ` Alexei Starovoitov
[not found] ` <1426542584-9406-3-git-send-email-ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-03-19 15:07 ` Steven Rostedt
2015-03-19 15:07 ` Steven Rostedt
[not found] ` <20150319110742.7dc9473d-f9ZlEuEWxVcJvu8Pb33WZ0EMvNT87kid@public.gmane.org>
2015-03-19 15:33 ` Alexei Starovoitov
2015-03-19 15:33 ` Alexei Starovoitov
2015-03-20 8:35 ` Masami Hiramatsu
2015-03-20 8:35 ` Masami Hiramatsu
2015-03-16 21:49 ` [PATCH v7 tip 4/8] tracing: allow BPF programs to call bpf_trace_printk() Alexei Starovoitov
2015-03-16 21:49 ` Alexei Starovoitov
[not found] ` <1426542584-9406-5-git-send-email-ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-03-19 15:29 ` Steven Rostedt
2015-03-19 15:29 ` Steven Rostedt
2015-03-19 15:51 ` Alexei Starovoitov
2015-03-16 21:49 ` [PATCH v7 tip 5/8] samples: bpf: simple non-portable kprobe filter example Alexei Starovoitov
2015-03-16 21:49 ` Alexei Starovoitov
[not found] ` <1426542584-9406-6-git-send-email-ast-uqk4Ao+rVK5Wk0Htik3J/w@public.gmane.org>
2015-03-19 15:50 ` Steven Rostedt
2015-03-19 15:50 ` Steven Rostedt
2015-03-19 15:53 ` Alexei Starovoitov
2015-03-16 21:49 ` [PATCH v7 tip 6/8] samples: bpf: counting example for kfree_skb and write syscall Alexei Starovoitov
2015-03-16 21:49 ` [PATCH v7 tip 7/8] samples: bpf: IO latency analysis (iosnoop/heatmap) Alexei Starovoitov
2015-03-16 21:49 ` [PATCH v7 tip 8/8] samples: bpf: kmem_alloc/free tracker Alexei Starovoitov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=550AED5D.3010700@plumgrid.com \
--to=ast-uqk4ao+rvk5wk0htik3j/w@public.gmane.org \
--cc=a.p.zijlstra-/NLkJaSkS4VmR6Xm/wNWPw@public.gmane.org \
--cc=acme-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org \
--cc=daniel-FeC+5ew28dpmcu3hnIyYJQ@public.gmane.org \
--cc=davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org \
--cc=jolsa-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \
--cc=linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=masami.hiramatsu.pt-FCd8Q96Dh0JBDgjK7y7TUQ@public.gmane.org \
--cc=mingo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
--cc=namhyung-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
--cc=netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=rostedt-nx8X9YLhiw1AfugRpC6u6w@public.gmane.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.