d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Added some (temporary) macros for debugging.

Browse Source 
New strategy for handling the TPR (Task Priority Register).
Test code to sync CPUs.
This commit is contained in:
Steve Passe 1997-07-06 23:50:12 +00:00
parent 69f0a823b2
commit 586f21e1cc
1 changed files with 91 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

92
sys/i386/i386/mplock.s
View File

@ -6,7 +6,7 @@
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
* ----------------------------------------------------------------------------
*
* $Id: mplock.s,v 1.3 1997/05/29 05:11:10 peter Exp $
* $Id: mplock.s,v 1.2 1997/07/06 23:20:04 smp Exp smp $
*
* Functions for locking between CPUs in a SMP system.
*
@ -21,6 +21,23 @@
*
*/
/*
* these are all temps for debugging CPUSTOP code
* they will (hopefully) go away soon...
*/
#define MARK_HITS
#define ADJUST_TPR
#define ADJUST_IPL_NOT
#define REALLY_STI
#ifdef MARK_HITS
#define MARK_HIT(X) \
movl _cpuid, %eax ; \
movl $X, _lhits(,%eax,4)
#else
#define MARK_HIT(X)
#endif /* MARK_HITS */
#include "opt_ddb.h"
#include "assym.s" /* system definitions */
#include <machine/specialreg.h> /* x86 special registers */
@ -56,9 +73,15 @@ NON_GPROF_ENTRY(MPgetlock)
jne 3f /* ...do not collect $200 */
#if defined(TEST_LOPRIO)
/* 1st acquire, claim LOW PRIO (ie, ALL INTerrupts) */
#ifdef ADJUST_TPR
movl 20(%esp), %eax /* saved copy */
andl $0xffffff00, %eax /* clear task priority field */
movl %eax, 20(%esp) /* 're-save' it */
#else
movl lapic_tpr, %eax /* Task Priority Register */
andl $0xffffff00, %eax /* clear task priority field */
movl %eax, lapic_tpr /* set it */
#endif /** ADJUST_TPR */
#endif /** TEST_LOPRIO */
ret
3: cmpl $0xffffffff, (%edx) /* Wait for it to become free */
@ -127,10 +150,48 @@ NON_GPROF_ENTRY(MPrellock)
* void get_mplock()
* -----------------
* All registers preserved
*
* Stack (after call to _MPgetlock):
*
* &mp_lock 4(%esp)
* edx 8(%esp)
* ecx 12(%esp)
* EFLAGS 16(%esp)
* local APIC TPR 20(%esp)
* OR
* ipl 20(%esp)
* eax 24(%esp)
*/
NON_GPROF_ENTRY(get_mplock)
pushl %eax
MARK_HIT(1)
#ifdef ADJUST_TPR
movl lapic_tpr, %eax /* get current TPR */
pushl %eax /* save current TPR */
pushfl /* save current EFLAGS */
btl $9, (%esp) /* test EI bit */
jc 1f /* INTs currently enabled */
andl $0xffffff00, %eax /* clear task priority field */
orl $0x50, %eax /* only allow IPIs
movl %eax, lapic_tpr /* set it */
#endif /* ADJUST_TPR */
#ifdef ADJUST_IPL
call _splhigh /* block all INTs EXCEPT IPIs */
pushl %eax /* save ipl */
pushfl /* save current EFLAGS */
btl $9, (%esp) /* test EI bit */
jc 1f /* INTs currently enabled */
#endif /* ADJUST_IPL */
#ifdef REALLY_STI
sti /* allow IPI (and only IPI) INTS */
#endif /* REALLY_STI */
1:
pushl %ecx
pushl %edx
pushl $_mp_lock
@ -138,6 +199,21 @@ NON_GPROF_ENTRY(get_mplock)
add $4, %esp
popl %edx
popl %ecx
MARK_HIT(0)
#ifdef ADJUST_TPR
popfl /* restore original EFLAGS */
popl %eax /* get original/modified TPR value */
movl %eax, lapic_tpr /* restore TPR */
#endif /* ADJUST_TPR */
#ifdef ADJUST_IPL
popfl /* restore original EFLAGS */
call _splx /* restore original ipl */
add $4, %esp
#endif /* ADJUST_IPL */
popl %eax
ret
@ -165,6 +241,9 @@ NON_GPROF_ENTRY(try_mplock)
NON_GPROF_ENTRY(rel_mplock)
pushl %eax
MARK_HIT(128)
pushl %ecx
pushl %edx
pushl $_mp_lock
@ -172,6 +251,9 @@ NON_GPROF_ENTRY(rel_mplock)
add $4, %esp
popl %edx
popl %ecx
MARK_HIT(0)
popl %eax
ret
@ -181,3 +263,11 @@ NON_GPROF_ENTRY(rel_mplock)
.align 2 /* mp_lock SHALL be aligned on i386 */
_mp_lock: .long 0
#ifdef MARK_HITS
.globl _lhits
_lhits:
.long 0
.long 0
.long 0
.long 0
#endif /* MARK_HITS */