All of lore.kernel.org
 help / color / mirror / Atom feed
From: Song Liu <songliubraving@fb.com>
To: Daniel Borkmann <daniel@iogearbox.net>
Cc: bpf <bpf@vger.kernel.org>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"ast@kernel.org" <ast@kernel.org>,
	Kernel Team <Kernel-team@fb.com>,
	"john.fastabend@gmail.com" <john.fastabend@gmail.com>,
	"kpsingh@chromium.org" <kpsingh@chromium.org>
Subject: Re: [PATCH bpf-next 2/3] bpf: allow %pB in bpf_seq_printf()
Date: Tue, 23 Jun 2020 17:19:27 +0000	[thread overview]
Message-ID: <823792EE-E55E-439D-AA13-C8C6B7EDD00B@fb.com> (raw)
In-Reply-To: <677dc8f7-d4e9-7717-5def-935340a23cd2@iogearbox.net>



> On Jun 23, 2020, at 8:29 AM, Daniel Borkmann <daniel@iogearbox.net> wrote:
> 
> On 6/23/20 9:08 AM, Song Liu wrote:
>> This makes it easy to dump stack trace with bpf_seq_printf().
>> Signed-off-by: Song Liu <songliubraving@fb.com>
>> ---
>>  kernel/trace/bpf_trace.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
>> index 2c13bcb5c2bce..ced3176801ae8 100644
>> --- a/kernel/trace/bpf_trace.c
>> +++ b/kernel/trace/bpf_trace.c
>> @@ -636,7 +636,8 @@ BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
>>  		if (fmt[i] == 'p') {
>>  			if (fmt[i + 1] == 0 ||
>>  			    fmt[i + 1] == 'K' ||
>> -			    fmt[i + 1] == 'x') {
>> +			    fmt[i + 1] == 'x' ||
>> +			    fmt[i + 1] == 'B') {
>>  				/* just kernel pointers */
>>  				params[fmt_cnt] = args[fmt_cnt];
>>  				fmt_cnt++;
> 
> Why only bpf_seq_printf(), what about bpf_trace_printk()?

The use case we are looking at needs bpf_seq_printf(). Let me also add it to
bpf_trace_printk(). 

Thanks,
Song

  reply	other threads:[~2020-06-23 17:19 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-23  7:07 [PATCH bpf-next 0/3] bpf: introduce bpf_get_task_stack_trace() Song Liu
2020-06-23  7:08 ` [PATCH bpf-next 1/3] bpf: introduce helper bpf_get_task_stack_trace() Song Liu
2020-06-23 15:19   ` Alexei Starovoitov
2020-06-23 16:59     ` Song Liu
2020-06-23 17:40       ` Song Liu
2020-06-23 18:41       ` Andrii Nakryiko
2020-06-23 15:22   ` Daniel Borkmann
2020-06-23 17:19     ` Song Liu
2020-06-23 18:45   ` Andrii Nakryiko
2020-06-23 22:53     ` Song Liu
2020-06-23  7:08 ` [PATCH bpf-next 2/3] bpf: allow %pB in bpf_seq_printf() Song Liu
2020-06-23 15:29   ` Daniel Borkmann
2020-06-23 17:19     ` Song Liu [this message]
2020-06-23  7:08 ` [PATCH bpf-next 3/3] selftests/bpf: add bpf_iter test with bpf_get_task_stack_trace() Song Liu
2020-06-23 18:57   ` Yonghong Song
2020-06-23 22:07     ` Song Liu
2020-06-23 22:27       ` Yonghong Song
2020-06-24 20:37         ` Song Liu
2020-06-25  5:29           ` Yonghong Song

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=823792EE-E55E-439D-AA13-C8C6B7EDD00B@fb.com \
    --to=songliubraving@fb.com \
    --cc=Kernel-team@fb.com \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=john.fastabend@gmail.com \
    --cc=kpsingh@chromium.org \
    --cc=netdev@vger.kernel.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.