From: Tormod Volden <debian.tormod@gmail.com>
Date: Sun, 19 Apr 2015 16:43:44 +0000 (+0200)
Subject: dragon-nx32: Don't stuff uarea on switch to self
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=d893233e9dbda5a8ff6ca92a387b75c29a711a79;p=FUZIX.git

dragon-nx32: Don't stuff uarea on switch to self

A little bit of optimization. More can be done on
the amount being copied over.

Signed-off-by: Tormod Volden <debian.tormod@gmail.com>
---

diff --git a/Kernel/platform-dragon-nx32/tricks.s b/Kernel/platform-dragon-nx32/tricks.s
index d0a109d5..85baf85a 100644
--- a/Kernel/platform-dragon-nx32/tricks.s
+++ b/Kernel/platform-dragon-nx32/tricks.s
@@ -91,6 +91,11 @@ _switchin:
 	; get process table - must be in already from switchout
 	; jsr map_kernel
 	lda P_TAB__P_PAGE_OFFSET+1,x		; LSB of 16-bit page no
+
+	; if we are switching to the same process
+	cmpa U_DATA__U_PAGE+1
+	beq nostash
+
 	jsr map_process_a
 	
 	; fetch uarea from process memory
@@ -106,6 +111,7 @@ stashb	ldd ,x++
 	; get back kernel page so that we see process table
 	jsr map_kernel
 
+nostash:
 	;puls x
 	ldx _swapstack
         ; check u_data->u_ptab matches what we wanted