[src/trunk]: src/sys/arch/amd64/amd64 Comments.

[uebayasi <uebayasi%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/cc77c4f0810d
branches:  trunk
changeset: 334030:cc77c4f0810d
user:      uebayasi <uebayasi%NetBSD.org@localhost>
date:      Thu Nov 27 04:48:39 2014 +0000

description:
Comments.

diffstat:

 sys/arch/amd64/amd64/spl.S |  14 ++++++++------
 1 files changed, 8 insertions(+), 6 deletions(-)

diffs (59 lines):

diff -r b23931457772 -r cc77c4f0810d sys/arch/amd64/amd64/spl.S
--- a/sys/arch/amd64/amd64/spl.S        Thu Nov 27 04:41:55 2014 +0000
+++ b/sys/arch/amd64/amd64/spl.S        Thu Nov 27 04:48:39 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: spl.S,v 1.28 2014/01/12 20:31:50 joerg Exp $   */
+/*     $NetBSD: spl.S,v 1.29 2014/11/27 04:48:39 uebayasi Exp $        */
 
 /*
  * Copyright (c) 2003 Wasabi Systems, Inc.
@@ -115,7 +115,7 @@
        xchgq   %r15,CPUVAR(CURLWP)     /* must be globally visible */
        popq    %r15                    /* unwind switchframe */
        addq    $(5 * 8),%rsp
-       jmp     *%r13                   /* back to splx/doreti */
+       jmp     *%r13                   /* back to Xspllower/Xdoreti */
 END(Xsoftintr)
 
 /*
@@ -130,7 +130,7 @@
        incl    CPUVAR(MTX_COUNT)       /* re-adjust after mi_switch */
        movl    $0, L_CTXSWTCH(%rax)    /* %rax from cpu_switchto */
        cli
-       jmp     *%r13                   /* back to splx/doreti */
+       jmp     *%r13                   /* back to Xspllower/Xdoreti */
 END(softintr_ret)
 
 /*
@@ -155,7 +155,7 @@
        xorq    %rdi, %rdi
        call    _C_LABEL(kpreempt)
        cli
-       jmp     *%r13
+       jmp     *%r13                   /* back to Xspllower */
 END(Xpreemptrecurse)
 
 /*
@@ -171,11 +171,11 @@
        movq    TF_RIP(%rsp), %rdi
        call    _C_LABEL(kpreempt)              # from kernel
        cli
-       jmp     *%r13
+       jmp     *%r13                   /* back to Xdoreti */
 1:
        call    _C_LABEL(preempt)               # from user
        cli
-       jmp     *%r13
+       jmp     *%r13                   /* back to Xdoreti */
 END(Xpreemptresume)
 
 /*
@@ -303,6 +303,8 @@
 END(Xspllower)
 
 /*
+ * void Xdoreti(void);
+ * 
  * Handle return from interrupt after device handler finishes.
  *
  * Important registers: