linux-kernel - [PATCH 1/3] printk: Remove used-once early

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Date:	Thu, 30 Oct 2014 11:11:52 -0700
From:	Joe Perches <joe@...ches.com>
To:	Chris Metcalf <cmetcalf@...era.com>,
	Andrew Morton <akpm@...ux-foundation.org>
Cc:	linux-kernel@...r.kernel.org
Subject: [PATCH 1/3] printk: Remove used-once early_vprintk

Eliminate the unlikely possibility of message interleaving
for early_printk/early_vprintk use.

early_vprintk can be done via the %pV extension so remove
this unnecessary function and change early_printk to have
the equivalent vprintk code.

All uses of early_printk already end with a newline so also
remove the unnecessary newline from the early_printk function.

Signed-off-by: Joe Perches <joe@...ches.com>
---
 arch/tile/kernel/early_printk.c | 19 +++++++++++++------
 include/linux/printk.h          |  1 -
 kernel/printk/printk.c          | 19 ++++++++-----------
 3 files changed, 21 insertions(+), 18 deletions(-)

diff --git a/arch/tile/kernel/early_printk.c b/arch/tile/kernel/early_printk.c
index b608e00..aefb2c0 100644
--- a/arch/tile/kernel/early_printk.c
+++ b/arch/tile/kernel/early_printk.c
@@ -43,13 +43,20 @@ static struct console early_hv_console = {
 
 void early_panic(const char *fmt, ...)
 {
-	va_list ap;
+	struct va_format vaf;
+	va_list args;
+
 	arch_local_irq_disable_all();
-	va_start(ap, fmt);
-	early_printk("Kernel panic - not syncing: ");
-	early_vprintk(fmt, ap);
-	early_printk("\n");
-	va_end(ap);
+
+	va_start(args, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	early_printk("Kernel panic - not syncing: %pV", &vaf);
+
+	va_end(args);
+
 	dump_stack();
 	hv_halt();
 }
diff --git a/include/linux/printk.h b/include/linux/printk.h
index d78125f..3dd489f 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -118,7 +118,6 @@ int no_printk(const char *fmt, ...)
 #ifdef CONFIG_EARLY_PRINTK
 extern asmlinkage __printf(1, 2)
 void early_printk(const char *fmt, ...);
-void early_vprintk(const char *fmt, va_list ap);
 #else
 static inline __printf(1, 2) __cold
 void early_printk(const char *s, ...) { }
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index ced2b84..4815c98 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -1881,23 +1881,20 @@ static size_t cont_print_text(char *text, size_t size) { return 0; }
 #ifdef CONFIG_EARLY_PRINTK
 struct console *early_console;
 
-void early_vprintk(const char *fmt, va_list ap)
-{
-	if (early_console) {
-		char buf[512];
-		int n = vscnprintf(buf, sizeof(buf), fmt, ap);
-
-		early_console->write(early_console, buf, n);
-	}
-}
-
 asmlinkage __visible void early_printk(const char *fmt, ...)
 {
 	va_list ap;
+	char buf[512];
+	int n;
+
+	if (!early_console)
+		return;
 
 	va_start(ap, fmt);
-	early_vprintk(fmt, ap);
+	n = vscnprintf(buf, sizeof(buf), fmt, ap);
 	va_end(ap);
+
+	early_console->write(early_console, buf, n);
 }
 #endif
 
-- 
2.1.2

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