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- Add support for blocking and releasing threads to i386 cpu_switch(). This

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is required for per-cpu scheduler lock support.

Obtained from:	attilio
Tested by:	current@ many users
Approved by:	re
This commit is contained in:
Jeff Roberson 2007-07-17 22:34:14 +00:00
parent ab1438fb95
commit 56a114967b
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=171480
2 changed files with 30 additions and 3 deletions
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1
sys/i386/i386/genassym.c
View File

@ -81,6 +81,7 @@ ASSYM(PM_ACTIVE, offsetof(struct pmap, pm_active));
ASSYM(P_SFLAG, offsetof(struct proc, p_sflag));
ASSYM(TD_FLAGS, offsetof(struct thread, td_flags));
ASSYM(TD_LOCK, offsetof(struct thread, td_lock));
ASSYM(TD_PCB, offsetof(struct thread, td_pcb));
ASSYM(TD_PROC, offsetof(struct thread, td_proc));
ASSYM(TD_MD, offsetof(struct thread, td_md));

32
sys/i386/i386/swtch.s
View File

@ -33,11 +33,28 @@
*/
#include "opt_npx.h"
#include "opt_sched.h"
#include <machine/asmacros.h>
#include "assym.s"
#if defined(SMP) && defined(SCHED_ULE)
#define SETOP xchgl
#define BLOCK_SPIN(reg) \
movl $blocked_lock,%eax ; \
100: ; \
lock ; \
cmpxchgl %eax,TD_LOCK(reg) ; \
jne 101f ; \
pause ; \
jmp 100b ; \
101:
#else
#define SETOP movl
#define BLOCK_SPIN(reg)
#endif
/*****************************************************************************/
/* Scheduling */
/*****************************************************************************/
@ -91,6 +108,7 @@ ENTRY(cpu_throw)
* 0(%esp) = ret
* 4(%esp) = oldtd
* 8(%esp) = newtd
* 12(%esp) = newlock
*/
ENTRY(cpu_switch)
@ -145,13 +163,14 @@ ENTRY(cpu_switch)
#endif
/* Save is done. Now fire up new thread. Leave old vmspace. */
movl 4(%esp),%edi
movl 8(%esp),%ecx /* New thread */
movl 12(%esp),%esi /* New lock */
#ifdef INVARIANTS
testl %ecx,%ecx /* no thread? */
jz badsw3 /* no, panic */
#endif
movl TD_PCB(%ecx),%edx
movl PCPU(CPUID), %esi
/* switch address space */
movl PCB_CR3(%edx),%eax
@ -160,11 +179,14 @@ ENTRY(cpu_switch)
#else
cmpl %eax,IdlePTD /* Kernel address space? */
#endif
je sw1
je sw0
movl %cr3,%ebx /* The same address space? */
cmpl %ebx,%eax
je sw1
je sw0
movl %eax,%cr3 /* new address space */
movl %esi,%eax
movl PCPU(CPUID),%esi
SETOP %eax,TD_LOCK(%edi) /* Switchout td_lock */
/* Release bit from old pmap->pm_active */
movl PCPU(CURPMAP), %ebx
@ -182,8 +204,12 @@ ENTRY(cpu_switch)
lock
#endif
btsl %esi, PM_ACTIVE(%ebx) /* set new */
jmp sw1
sw0:
SETOP %esi,TD_LOCK(%edi) /* Switchout td_lock */
sw1:
BLOCK_SPIN(%ecx)
/*
* At this point, we've switched address spaces and are ready
* to load up the rest of the next context.