linux-kernel - [PATCH printk v8 18/35] printk: Add @flags argument for console_is

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Message-Id: <20240820063001.36405-19-john.ogness@linutronix.de>
Date: Tue, 20 Aug 2024 08:35:44 +0206
From: John Ogness <john.ogness@...utronix.de>
To: Petr Mladek <pmladek@...e.com>
Cc: Sergey Senozhatsky <senozhatsky@...omium.org>,
	Steven Rostedt <rostedt@...dmis.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	linux-kernel@...r.kernel.org
Subject: [PATCH printk v8 18/35] printk: Add @flags argument for console_is_usable()

The caller of console_is_usable() usually needs @console->flags
for its own checks. Rather than having console_is_usable() read
its own copy, make the caller pass in the @flags. This also
ensures that the caller saw the same @flags value.

Signed-off-by: John Ogness <john.ogness@...utronix.de>
Reviewed-by: Petr Mladek <pmladek@...e.com>
---
 kernel/printk/internal.h | 8 ++------
 kernel/printk/printk.c   | 5 +++--
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/kernel/printk/internal.h b/kernel/printk/internal.h
index 448a5fcd5228..fe8d84d78f1c 100644
--- a/kernel/printk/internal.h
+++ b/kernel/printk/internal.h
@@ -89,13 +89,9 @@ void nbcon_free(struct console *con);
  * records. Note that this function does not consider the current context,
  * which can also play a role in deciding if @con can be used to print
  * records.
- *
- * Requires the console_srcu_read_lock.
  */
-static inline bool console_is_usable(struct console *con)
+static inline bool console_is_usable(struct console *con, short flags)
 {
-	short flags = console_srcu_read_flags(con);
-
 	if (!(flags & CON_ENABLED))
 		return false;
 
@@ -141,7 +137,7 @@ static inline void nbcon_seq_force(struct console *con, u64 seq) { }
 static inline bool nbcon_alloc(struct console *con) { return false; }
 static inline void nbcon_free(struct console *con) { }
 
-static inline bool console_is_usable(struct console *con) { return false; }
+static inline bool console_is_usable(struct console *con, short flags) { return false; }
 
 #endif /* CONFIG_PRINTK */
 
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index b9c8fff9a493..ffb56c2150b0 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -3012,9 +3012,10 @@ static bool console_flush_all(bool do_cond_resched, u64 *next_seq, bool *handove
 
 		cookie = console_srcu_read_lock();
 		for_each_console_srcu(con) {
+			short flags = console_srcu_read_flags(con);
 			bool progress;
 
-			if (!console_is_usable(con))
+			if (!console_is_usable(con, flags))
 				continue;
 			any_usable = true;
 
@@ -3925,7 +3926,7 @@ static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progre
 			 * that they make forward progress, so only increment
 			 * @diff for usable consoles.
 			 */
-			if (!console_is_usable(c))
+			if (!console_is_usable(c, flags))
 				continue;
 
 			if (flags & CON_NBCON) {
-- 
2.39.2