From 00499bb97b4a661f328ed4bed0deed3cadbaba12 Mon Sep 17 00:00:00 2001
From: Stefan Lankes <slankes@eonerc.rwth-aachen.de>
Date: Tue, 2 Aug 2016 20:30:52 +0200
Subject: [PATCH] add IO lock to get nicer output messages

---
 hermit/kernel/syscall.c |  3 +++
 hermit/libkern/printf.c | 12 +++++++++++-
 hermit/libkern/stdio.c  | 12 +++++-------
 3 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/hermit/kernel/syscall.c b/hermit/kernel/syscall.c
index f3d74181d..1788933e7 100644
--- a/hermit/kernel/syscall.c
+++ b/hermit/kernel/syscall.c
@@ -45,6 +45,7 @@
 //TODO: don't use one big kernel lock to comminicate with all proxies
 static spinlock_t lwip_lock = SPINLOCK_INIT;
 
+extern spinlock_irqsave_t stdio_lock;
 extern int32_t isle;
 extern int32_t possible_isles;
 extern volatile int libc_sd;
@@ -191,8 +192,10 @@ ssize_t sys_write(int fd, const char* buf, size_t len)
 	{
 		spinlock_unlock(&lwip_lock);
 
+		spinlock_irqsave_lock(&stdio_lock);
 		for(i=0; i<len; i++)
 			kputchar(buf[i]);
+		spinlock_irqsave_unlock(&stdio_lock);
 
 		return len;
 	}
diff --git a/hermit/libkern/printf.c b/hermit/libkern/printf.c
index e1345b91f..a666af6cc 100644
--- a/hermit/libkern/printf.c
+++ b/hermit/libkern/printf.c
@@ -45,6 +45,7 @@
  */
 
 #include <hermit/string.h>
+#include <hermit/spinlock.h>
 
 /* HermitCore use only the 64bit version */
 #define __64BIT__
@@ -75,6 +76,8 @@ static char const hex2ascii_data[] = "0123456789abcdefghijklmnopqrstuvwxyz";
 /* Max number conversion buffer length: a u_quad_t in base 2, plus NUL byte. */
 #define MAXNBUF	(sizeof(intmax_t) * NBBY + 1)
 
+extern spinlock_irqsave_t stdio_lock;
+
 /*
  * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
  * order; return an optional length and a pointer to the last character
@@ -150,12 +153,16 @@ int kvprintf(char const *fmt, void (*func) (int, void *), void *arg, int radix,
 	if (radix < 2 || radix > 36)
 		radix = 10;
 
+	spinlock_irqsave_lock(&stdio_lock);
+
 	for (;;) {
 		padc = ' ';
 		width = 0;
 		while ((ch = (u_char) * fmt++) != '%' || stop) {
-			if (ch == '\0')
+			if (ch == '\0') {
+				spinlock_irqsave_unlock(&stdio_lock);
 				return (retval);
+			}
 			PCHAR(ch);
 		}
 		percent = fmt - 1;
@@ -449,6 +456,9 @@ int kvprintf(char const *fmt, void (*func) (int, void *), void *arg, int radix,
 			break;
 		}
 	}
+
+	spinlock_irqsave_unlock(&stdio_lock);
+
 #undef PCHAR
 }
 
diff --git a/hermit/libkern/stdio.c b/hermit/libkern/stdio.c
index dcd7ed83e..8c4eee2a4 100644
--- a/hermit/libkern/stdio.c
+++ b/hermit/libkern/stdio.c
@@ -36,9 +36,7 @@
 #include <asm/uart.h>
 
 static atomic_int32_t kmsg_counter = ATOMIC_INIT(-1);
-#ifdef CONFIG_VGA
-static spinlock_irqsave_t vga_lock = SPINLOCK_IRQSAVE_INIT;
-#endif
+spinlock_irqsave_t stdio_lock = SPINLOCK_IRQSAVE_INIT;
 
 /* Workaround for a compiler bug. gcc 5.1 seems to ignore this array, if we
    defined it as as static array. At least it is as static array not part of
@@ -72,9 +70,7 @@ int kputchar(int c)
 
 	if (is_single_kernel()) {
 #ifdef CONFIG_VGA
-		spinlock_irqsave_lock(&vga_lock);
 		vga_putchar(c);
-		spinlock_irqsave_unlock(&vga_lock);
 #else
 		uart_putchar(c);
 #endif
@@ -87,6 +83,8 @@ int kputs(const char *str)
 {
 	int pos, i, len = strlen(str);
 
+	spinlock_irqsave_lock(&stdio_lock);
+
 	for(i=0; i<len; i++) {
 		pos = atomic_int32_inc(&kmsg_counter);
 		kmessages[pos % KMSG_SIZE] = str[i];
@@ -94,13 +92,13 @@ int kputs(const char *str)
 
 	if (is_single_kernel()) {
 #ifdef CONFIG_VGA
-		spinlock_irqsave_lock(&vga_lock);
 		vga_puts(str);
-		spinlock_irqsave_unlock(&vga_lock);
 #else
 		uart_puts(str);
 #endif
 	}
 
+	spinlock_irqsave_unlock(&stdio_lock);
+
 	return len;
 }