kernel: Optimize console & logging

* Modified draw loops to use `fbdev_get_index()` less often.
* Created `cons_fast_putch()`, then used it to implement `cons_putch()`
  and `cons_putstr()`. This way, when printing an entire string, the
  lock acquire/release and cursor hide/show will only happen once,
  instead of once per character.
* Modified `syslog_write()` to use `cons_putstr()`.

Signed-off-by: Quinn Stephens <quinn@osmora.org>
Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 9 insertions, 5 deletions

diff --git a/sys/kern/kern_syslog.c b/sys/kern/kern_syslog.c
index 665734d..656362e 100644
--- a/sys/kern/kern_syslog.c
+++ b/sys/kern/kern_syslog.c
@@ -46,15 +46,19 @@ static struct spinlock lock = {0};
 static void
 syslog_write(const char *s, size_t len)
 {
-    const char *p = s;
+    const char *p;
+    size_t l;
 
-    while (len--) {
-        cons_putch(&g_root_scr, *p);
-        if (SERIAL_DEBUG) {
+    if (SERIAL_DEBUG) {
+        p = s;
+        l = len;
+        while (l--) {
             serial_putc(*p);
+            ++p;
         }
-        ++p;
     }
+
+    cons_putstr(&g_root_scr, s, len);
 }
 
 /*