mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: John Ogness <john.ogness@linutronix.de>
To: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	linux-kernel@vger.kernel.org,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: [PATCH printk v5 2/8] console: Use BIT() macros for @flags values
Date: Mon,  9 Jan 2023 11:13:54 +0106	[thread overview]
Message-ID: <20230109100800.1085541-3-john.ogness@linutronix.de> (raw)
In-Reply-To: <20230109100800.1085541-1-john.ogness@linutronix.de>

From: Thomas Gleixner <tglx@linutronix.de>

Rather than manually calculating powers of 2, use the BIT() macros.
Also take this opportunatity to cleanup and restructure the value
comments into proper kerneldoc comments.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
---
 include/linux/console.h | 46 ++++++++++++++++++++++++++++++++---------
 1 file changed, 36 insertions(+), 10 deletions(-)

diff --git a/include/linux/console.h b/include/linux/console.h
index 9cea254b34b8..ed804dd7c2e8 100644
--- a/include/linux/console.h
+++ b/include/linux/console.h
@@ -15,6 +15,7 @@
 #define _LINUX_CONSOLE_H_ 1
 
 #include <linux/atomic.h>
+#include <linux/bits.h>
 #include <linux/rculist.h>
 #include <linux/types.h>
 
@@ -125,18 +126,43 @@ static inline int con_debug_leave(void)
 /*
  * The interface for a console, or any other device that wants to capture
  * console messages (printer driver?)
- *
- * If a console driver is marked CON_BOOT then it will be auto-unregistered
- * when the first real console is registered.  This is for early-printk drivers.
  */
 
-#define CON_PRINTBUFFER	(1)
-#define CON_CONSDEV	(2) /* Preferred console, /dev/console */
-#define CON_ENABLED	(4)
-#define CON_BOOT	(8)
-#define CON_ANYTIME	(16) /* Safe to call when cpu is offline */
-#define CON_BRL		(32) /* Used for a braille device */
-#define CON_EXTENDED	(64) /* Use the extended output format a la /dev/kmsg */
+/**
+ * cons_flags - General console flags
+ * @CON_PRINTBUFFER:	Used by newly registered consoles to avoid duplicate
+ *			output of messages that were already shown by boot
+ *			consoles or read by userspace via syslog() syscall.
+ * @CON_CONSDEV:	Indicates that the console driver is backing
+ *			/dev/console.
+ * @CON_ENABLED:	Indicates if a console is allowed to print records. If
+ *			false, the console also will not advance to later
+ *			records.
+ * @CON_BOOT:		Marks the console driver as early console driver which
+ *			is used during boot before the real driver becomes
+ *			available. It will be automatically unregistered
+ *			when the real console driver is registered unless
+ *			"keep_bootcon" parameter is used.
+ * @CON_ANYTIME:	A misnomed historical flag which tells the core code
+ *			that the legacy @console::write callback can be invoked
+ *			on a CPU which is marked OFFLINE. That is misleading as
+ *			it suggests that there is no contextual limit for
+ *			invoking the callback. The original motivation was
+ *			readiness of the per-CPU areas.
+ * @CON_BRL:		Indicates a braille device which is exempt from
+ *			receiving the printk spam for obvious reasons.
+ * @CON_EXTENDED:	The console supports the extended output format of
+ *			/dev/kmesg which requires a larger output buffer.
+ */
+enum cons_flags {
+	CON_PRINTBUFFER		= BIT(0),
+	CON_CONSDEV		= BIT(1),
+	CON_ENABLED		= BIT(2),
+	CON_BOOT		= BIT(3),
+	CON_ANYTIME		= BIT(4),
+	CON_BRL			= BIT(5),
+	CON_EXTENDED		= BIT(6),
+};
 
 struct console {
 	char	name[16];
-- 
2.30.2


  parent reply	other threads:[~2023-01-09 10:09 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-09 10:07 [PATCH printk v5 0/8] printk: cleanup buffer handling John Ogness
2023-01-09 10:07 ` [PATCH printk v5 1/8] printk: move size limit macros into internal.h John Ogness
2023-01-09 10:07 ` John Ogness [this message]
2023-01-09 10:07 ` [PATCH printk v5 3/8] console: Document struct console John Ogness
2023-01-09 10:07 ` [PATCH printk v5 4/8] printk: introduce struct printk_buffers John Ogness
2023-01-09 10:07 ` [PATCH printk v5 5/8] printk: introduce printk_get_next_message() and printk_message John Ogness
2023-01-09 10:07 ` [PATCH printk v5 6/8] printk: introduce console_prepend_dropped() for dropped messages John Ogness
2023-01-09 14:12   ` Petr Mladek
2023-01-09 10:07 ` [PATCH printk v5 7/8] printk: use printk_buffers for devkmsg John Ogness
2023-01-09 14:23   ` Petr Mladek
2023-01-09 10:08 ` [PATCH printk v5 8/8] printk: adjust string limit macros John Ogness
2023-01-09 15:10 ` [PATCH printk v5 0/8] printk: cleanup buffer handling Petr Mladek
2023-01-11 15:36   ` Petr Mladek

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=20230109100800.1085541-3-john.ogness@linutronix.de \
    --to=john.ogness@linutronix.de \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pmladek@suse.com \
    --cc=rostedt@goodmis.org \
    --cc=senozhatsky@chromium.org \
    --cc=tglx@linutronix.de \
    /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

all inboxes | Powered by JetHome®