From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: John Ogness <john.ogness@linutronix.de>
Cc: Andrea Parri <andrea.parri@amarulasolutions.com>,
Petr Mladek <pmladek@suse.com>,
Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
Peter Zijlstra <peterz@infradead.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Brendan Higgins <brendanhiggins@google.com>,
linux-kernel@vger.kernel.org,
Steven Rostedt <rostedt@goodmis.org>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
Thomas Gleixner <tglx@linutronix.de>,
Linus Torvalds <torvalds@linux-foundation.org>,
kexec@lists.infradead.org
Subject: Re: [RFC PATCH v5 1/3] printk-rb: new printk ringbuffer implementation (writer)
Date: Mon, 9 Dec 2019 18:27:56 +0900 [thread overview]
Message-ID: <20191209092756.GH88619@google.com> (raw)
In-Reply-To: <20191128015235.12940-2-john.ogness@linutronix.de>
On (19/11/28 02:58), John Ogness wrote:
> + * Sample reader code::
> + *
> + * struct printk_info info;
> + * char text_buf[32];
> + * char dict_buf[32];
> + * u64 next_seq = 0;
> + * struct printk_record r = {
> + * .info = &info,
> + * .text_buf = &text_buf[0],
> + * .dict_buf = &dict_buf[0],
> + * .text_buf_size = sizeof(text_buf),
> + * .dict_buf_size = sizeof(dict_buf),
> + * };
> + *
> + * while (prb_read_valid(&rb, next_seq, &r)) {
> + * if (info.seq != next_seq)
> + * pr_warn("lost %llu records\n", info.seq - next_seq);
> + *
> + * if (info.text_len > r.text_buf_size) {
> + * pr_warn("record %llu text truncated\n", info.seq);
> + * text_buf[sizeof(text_buf) - 1] = 0;
> + * }
> + *
> + * if (info.dict_len > r.dict_buf_size) {
> + * pr_warn("record %llu dict truncated\n", info.seq);
> + * dict_buf[sizeof(dict_buf) - 1] = 0;
> + * }
> + *
> + * pr_info("%llu: %llu: %s;%s\n", info.seq, info.ts_nsec,
> + * &text_buf[0], info.dict_len ? &dict_buf[0] : "");
> + *
> + * next_seq = info.seq + 1;
> + * }
> + */
Will this loop ever end? :)
pr_info() adds data to ringbuffer, which prb_read_valid() reads, so pr_info()
can add more data, which prb_read_valid() will read, so pr_info()...
-ss
_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec
next prev parent reply other threads:[~2019-12-09 9:28 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-28 1:52 [RFC PATCH v5 0/3] printk: new ringbuffer implementation John Ogness
2019-11-28 1:52 ` [RFC PATCH v5 1/3] printk-rb: new printk ringbuffer implementation (writer) John Ogness
2019-12-02 15:48 ` Petr Mladek
2019-12-02 15:59 ` Petr Mladek
2019-12-02 16:37 ` John Ogness
2019-12-03 1:17 ` Sergey Senozhatsky
2019-12-03 14:18 ` Steven Rostedt
2019-12-05 12:01 ` John Ogness
2019-12-03 8:54 ` Petr Mladek
2019-12-03 14:13 ` John Ogness
2019-12-03 14:36 ` Petr Mladek
2019-12-09 9:19 ` Sergey Senozhatsky
2019-12-09 7:42 ` Sergey Senozhatsky
2019-12-09 9:00 ` John Ogness
2019-12-09 9:27 ` Sergey Senozhatsky [this message]
2019-12-09 9:34 ` John Ogness
2019-12-21 14:22 ` Andrea Parri
2019-12-23 16:01 ` John Ogness
2019-11-28 1:52 ` [RFC PATCH v5 2/3] printk-rb: new printk ringbuffer implementation (reader) John Ogness
2019-12-03 12:06 ` Petr Mladek
2019-12-03 13:46 ` John Ogness
2019-12-04 12:54 ` Petr Mladek
2019-12-04 13:28 ` John Ogness
2019-12-09 8:43 ` Sergey Senozhatsky
2019-12-09 9:03 ` Sergey Senozhatsky
2019-12-09 9:09 ` John Ogness
2019-11-28 1:52 ` [RFC PATCH v5 3/3] printk-rb: add test module John Ogness
2019-12-09 8:44 ` Sergey Senozhatsky
2019-12-05 13:46 ` [RFC PATCH v5 0/3] printk: new ringbuffer implementation Prarit Bhargava
2019-12-05 14:05 ` John Ogness
2019-12-06 14:16 ` Prarit Bhargava
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=20191209092756.GH88619@google.com \
--to=sergey.senozhatsky.work@gmail.com \
--cc=andrea.parri@amarulasolutions.com \
--cc=brendanhiggins@google.com \
--cc=gregkh@linuxfoundation.org \
--cc=john.ogness@linutronix.de \
--cc=kexec@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=peterz@infradead.org \
--cc=pmladek@suse.com \
--cc=rostedt@goodmis.org \
--cc=sergey.senozhatsky@gmail.com \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox