From: Alan Cox <alan@linux.intel.com>
Date: Sat, 18 Aug 2018 19:34:16 +0000 (+0100)
Subject: tty: note an optimization area
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=f8164c5c83b0b16c2841d0dd8b8f0e54480014a0;p=FUZIX.git

tty: note an optimization area
---

diff --git a/Kernel/tty.c b/Kernel/tty.c
index eba4444f..1116c4b1 100644
--- a/Kernel/tty.c
+++ b/Kernel/tty.c
@@ -123,6 +123,15 @@ int tty_write(uint8_t minor, uint8_t rawflag, uint8_t flag)
 			if (psleep_flags_io(&t->flag, flag))
 				return udata.u_done;
 		}
+		/* We could optimize this significantly by 
+		   a) looping here if not sleeping rather than repeating all
+		   the checks except for STOP/DISCARD
+		   b) possibly batching for the case where tty never blocks
+		   if we have a way to report that. We could then batch except
+		   for conversions and also fast path in vt for 'normal char
+		   next char normal'
+		   c) look at hint/batching for ugetc into a local work buffer
+		*/
 		if (!(t->flag & TTYF_DISCARD)) {
 			if (udata.u_sysio)
 				c = *udata.u_base;