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freebsd-dev/sys/i386/isa/intr_machdep.h
Peter Wemm cc66ebe2a9 Commit a partial lazy thread switch mechanism for i386. it isn't as lazy 
as it could be and can do with some more cleanup.  Currently its under
options LAZY_SWITCH.  What this does is avoid %cr3 reloads for short
context switches that do not involve another user process.  ie: we can
take an interrupt, switch to a kthread and return to the user without
explicitly flushing the tlb.  However, this isn't as exciting as it could
be, the interrupt overhead is still high and too much blocks on Giant
still.  There are some debug sysctls, for stats and for an on/off switch.

The main problem with doing this has been "what if the process that you're
running on exits while we're borrowing its address space?" - in this case
we use an IPI to give it a kick when we're about to reclaim the pmap.

Its not compiled in unless you add the LAZY_SWITCH option.  I want to fix a
few more things and get some more feedback before turning it on by default.

This is NOT a replacement for Bosko's lazy interrupt stuff.  This was more
meant for the kthread case, while his was for interrupts.  Mine helps a
little for interrupts, but his helps a lot more.

The stats are enabled with options SWTCH_OPTIM_STATS - this has been a
pseudo-option for years, I just added a bunch of stuff to it.

One non-trivial change was to select a new thread before calling
cpu_switch() in the first place.  This allows us to catch the silly
case of doing a cpu_switch() to the current process.  This happens
uncomfortably often.  This simplifies a bit of the asm code in cpu_switch
(no longer have to call choosethread() in the middle).  This has been
implemented on i386 and (thanks to jake) sparc64.  The others will come
soon.  This is actually seperate to the lazy switch stuff.

Glanced at by:  jake, jhb
2003-04-02 23:53:30 +00:00

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/*-
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _I386_ISA_INTR_MACHDEP_H_
#define _I386_ISA_INTR_MACHDEP_H_
/*
* Low level interrupt code.
*/
#ifdef _KERNEL
#if defined(SMP) || defined(APIC_IO)
/*
* XXX FIXME: rethink location for all IPI vectors.
*/
/*
APIC TPR priority vector levels:
0xff (255) +-------------+
| | 15 (IPIs: Xspuriousint)
0xf0 (240) +-------------+
| | 14
0xe0 (224) +-------------+
| | 13
0xd0 (208) +-------------+
| | 12
0xc0 (192) +-------------+
| | 11
0xb0 (176) +-------------+
| | 10 (IPIs: Xcpustop)
0xa0 (160) +-------------+
| | 9 (IPIs: Xinvltlb)
0x90 (144) +-------------+
| | 8 (linux/BSD syscall, IGNORE FAST HW INTS)
0x80 (128) +-------------+
| | 7 (FAST_INTR 16-23)
0x70 (112) +-------------+
| | 6 (FAST_INTR 0-15)
0x60 (96) +-------------+
| | 5 (IGNORE HW INTS)
0x50 (80) +-------------+
| | 4 (2nd IO APIC)
0x40 (64) +------+------+
| | | 3 (upper APIC hardware INTs: PCI)
0x30 (48) +------+------+
| | 2 (start of hardware INTs: ISA)
0x20 (32) +-------------+
| | 1 (exceptions, traps, etc.)
0x10 (16) +-------------+
| | 0 (exceptions, traps, etc.)
0x00 (0) +-------------+
*/
/* IDT vector base for regular (aka. slow) and fast interrupts */
#define TPR_SLOW_INTS 0x20
#define TPR_FAST_INTS 0x60
/* XXX note that the AST interrupt is at 0x50 */
/* blocking values for local APIC Task Priority Register */
#define TPR_BLOCK_HWI 0x4f /* hardware INTs */
#define TPR_IGNORE_HWI 0x5f /* ignore INTs */
#define TPR_BLOCK_FHWI 0x7f /* hardware FAST INTs */
#define TPR_IGNORE_FHWI 0x8f /* ignore FAST INTs */
#define TPR_BLOCK_XINVLTLB 0x9f /* */
#define TPR_BLOCK_XCPUSTOP 0xaf /* */
#define TPR_BLOCK_ALL 0xff /* all INTs */
#ifdef TEST_TEST1
/* put a 'fake' HWI in top of APIC prio 0x3x, 32 + 31 = 63 = 0x3f */
#define XTEST1_OFFSET (ICU_OFFSET + 31)
#endif /** TEST_TEST1 */
/* TLB shootdowns */
#define XINVLTLB_OFFSET (ICU_OFFSET + 112) /* 0x90 */
#define XINVLPG_OFFSET (ICU_OFFSET + 113) /* 0x91 */
#define XINVLRNG_OFFSET (ICU_OFFSET + 114) /* 0x92 */
/* inter-cpu clock handling */
#define XHARDCLOCK_OFFSET (ICU_OFFSET + 120) /* 0x98 */
#define XSTATCLOCK_OFFSET (ICU_OFFSET + 121) /* 0x99 */
/* inter-CPU rendezvous */
#define XRENDEZVOUS_OFFSET (ICU_OFFSET + 122) /* 0x9A */
/* lazy pmap release */
#define XLAZYPMAP_OFFSET (ICU_OFFSET + 123) /* 0x9B */
/* IPI to generate an additional software trap at the target CPU */
/* XXX in the middle of the interrupt range, overlapping IRQ48 */
#define XCPUAST_OFFSET (ICU_OFFSET + 48) /* 0x50 */
/* IPI to signal CPUs to stop and wait for another CPU to restart them */
#define XCPUSTOP_OFFSET (ICU_OFFSET + 128) /* 0xA0 */
/*
* Note: this vector MUST be xxxx1111, 32 + 223 = 255 = 0xff:
*/
#define XSPURIOUSINT_OFFSET (ICU_OFFSET + 223)
#endif /* SMP || APIC_IO */
#ifdef LOCORE
/*
* Protects the IO APIC, 8259 PIC, imen, and apic_imen
*/
#define ICU_LOCK MTX_LOCK_SPIN(icu_lock, 0)
#define ICU_UNLOCK MTX_UNLOCK_SPIN(icu_lock)
#else /* LOCORE */
/*
* Type of the first (asm) part of an interrupt handler.
*/
typedef void inthand_t(u_int cs, u_int ef, u_int esp, u_int ss);
typedef void unpendhand_t(void);
#define IDTVEC(name) __CONCAT(X,name)
extern u_long *intr_countp[]; /* pointers into intrcnt[] */
extern driver_intr_t *intr_handler[]; /* C entry points of intr handlers */
extern struct ithd *ithds[];
extern void *intr_unit[]; /* cookies to pass to intr handlers */
extern struct mtx icu_lock;
inthand_t
IDTVEC(fastintr0), IDTVEC(fastintr1),
IDTVEC(fastintr2), IDTVEC(fastintr3),
IDTVEC(fastintr4), IDTVEC(fastintr5),
IDTVEC(fastintr6), IDTVEC(fastintr7),
IDTVEC(fastintr8), IDTVEC(fastintr9),
IDTVEC(fastintr10), IDTVEC(fastintr11),
IDTVEC(fastintr12), IDTVEC(fastintr13),
IDTVEC(fastintr14), IDTVEC(fastintr15);
inthand_t
IDTVEC(intr0), IDTVEC(intr1), IDTVEC(intr2), IDTVEC(intr3),
IDTVEC(intr4), IDTVEC(intr5), IDTVEC(intr6), IDTVEC(intr7),
IDTVEC(intr8), IDTVEC(intr9), IDTVEC(intr10), IDTVEC(intr11),
IDTVEC(intr12), IDTVEC(intr13), IDTVEC(intr14), IDTVEC(intr15);
unpendhand_t
IDTVEC(fastunpend0), IDTVEC(fastunpend1), IDTVEC(fastunpend2),
IDTVEC(fastunpend3), IDTVEC(fastunpend4), IDTVEC(fastunpend5),
IDTVEC(fastunpend6), IDTVEC(fastunpend7), IDTVEC(fastunpend8),
IDTVEC(fastunpend9), IDTVEC(fastunpend10), IDTVEC(fastunpend11),
IDTVEC(fastunpend12), IDTVEC(fastunpend13), IDTVEC(fastunpend14),
IDTVEC(fastunpend15), IDTVEC(fastunpend16), IDTVEC(fastunpend17),
IDTVEC(fastunpend18), IDTVEC(fastunpend19), IDTVEC(fastunpend20),
IDTVEC(fastunpend21), IDTVEC(fastunpend22), IDTVEC(fastunpend23),
IDTVEC(fastunpend24), IDTVEC(fastunpend25), IDTVEC(fastunpend26),
IDTVEC(fastunpend27), IDTVEC(fastunpend28), IDTVEC(fastunpend29),
IDTVEC(fastunpend30), IDTVEC(fastunpend31);
#if defined(SMP) || defined(APIC_IO)
inthand_t
IDTVEC(fastintr16), IDTVEC(fastintr17),
IDTVEC(fastintr18), IDTVEC(fastintr19),
IDTVEC(fastintr20), IDTVEC(fastintr21),
IDTVEC(fastintr22), IDTVEC(fastintr23),
IDTVEC(fastintr24), IDTVEC(fastintr25),
IDTVEC(fastintr26), IDTVEC(fastintr27),
IDTVEC(fastintr28), IDTVEC(fastintr29),
IDTVEC(fastintr30), IDTVEC(fastintr31);
inthand_t
IDTVEC(intr16), IDTVEC(intr17), IDTVEC(intr18), IDTVEC(intr19),
IDTVEC(intr20), IDTVEC(intr21), IDTVEC(intr22), IDTVEC(intr23),
IDTVEC(intr24), IDTVEC(intr25), IDTVEC(intr26), IDTVEC(intr27),
IDTVEC(intr28), IDTVEC(intr29), IDTVEC(intr30), IDTVEC(intr31);
inthand_t
Xinvltlb, /* TLB shootdowns - global */
Xinvlpg, /* TLB shootdowns - 1 page */
Xinvlrng, /* TLB shootdowns - page range */
Xhardclock, /* Forward hardclock() */
Xstatclock, /* Forward statclock() */
Xcpuast, /* Additional software trap on other cpu */
Xcpustop, /* CPU stops & waits for another CPU to restart it */
Xspuriousint, /* handle APIC "spurious INTs" */
Xrendezvous, /* handle CPU rendezvous */
Xlazypmap; /* handle lazy pmap release */
#ifdef TEST_TEST1
inthand_t
Xtest1; /* 'fake' HWI at top of APIC prio 0x3x, 32+31 = 0x3f */
#endif /** TEST_TEST1 */
#endif /* SMP || APIC_IO */
#ifdef APIC_IO
/*
* This is to accommodate "mixed-mode" programming for
* motherboards that don't connect the 8254 to the IO APIC.
*/
#define AUTO_EOI_1 1
#endif
#define NR_INTRNAMES (1 + ICU_LEN + 2 * ICU_LEN)
void isa_defaultirq(void);
int isa_nmi(int cd);
int icu_setup(int intr, driver_intr_t *func, void *arg, int flags);
int icu_unset(int intr, driver_intr_t *handler);
void icu_reinit(void);
/*
* WARNING: These are internal functions and not to be used by device drivers!
* They are subject to change without notice.
*/
int inthand_add(const char *name, int irq, driver_intr_t handler, void *arg,
enum intr_type flags, void **cookiep);
int inthand_remove(void *cookie);
void sched_ithd(void *dummy);
void call_fast_unpend(int irq);
#endif /* LOCORE */
#endif /* _KERNEL */
#endif /* !_I386_ISA_INTR_MACHDEP_H_ */
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