2 * Copyright (c) 1997 Bruce Evans.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * $FreeBSD: src/sys/i386/isa/ipl_funcs.c,v 1.32.2.5 2002/12/17 18:04:02 sam Exp $
27 * $DragonFly: src/sys/i386/isa/Attic/ipl_funcs.c,v 1.2 2003/06/17 04:28:37 dillon Exp $
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/sysctl.h>
34 #include <machine/ipl.h>
35 #include <machine/globals.h>
36 #include <i386/isa/intr_machdep.h>
39 * Bits in the ipending bitmap variable must be set atomically because
40 * ipending may be manipulated by interrupts or other cpu's without holding
43 * Note: setbits uses a locked or, making simple cases MP safe.
45 #define DO_SETBITS(name, var, bits) \
48 atomic_set_int(var, bits); \
51 DO_SETBITS(setdelayed, &ipending, loadandclear(&idelayed))
53 DO_SETBITS(setsoftcamnet,&ipending, SWI_CAMNET_PENDING)
54 DO_SETBITS(setsoftcambio,&ipending, SWI_CAMBIO_PENDING)
55 DO_SETBITS(setsoftclock, &ipending, SWI_CLOCK_PENDING)
56 DO_SETBITS(setsoftnet, &ipending, SWI_NET_PENDING)
57 DO_SETBITS(setsofttty, &ipending, SWI_TTY_PENDING)
58 DO_SETBITS(setsoftvm, &ipending, SWI_VM_PENDING)
59 DO_SETBITS(setsofttq, &ipending, SWI_TQ_PENDING)
60 DO_SETBITS(setsoftcrypto,&ipending, SWI_CRYPTO_PENDING)
62 DO_SETBITS(schedsoftcamnet, &idelayed, SWI_CAMNET_PENDING)
63 DO_SETBITS(schedsoftcambio, &idelayed, SWI_CAMBIO_PENDING)
64 DO_SETBITS(schedsoftnet, &idelayed, SWI_NET_PENDING)
65 DO_SETBITS(schedsofttty, &idelayed, SWI_TTY_PENDING)
66 DO_SETBITS(schedsoftvm, &idelayed, SWI_VM_PENDING)
67 DO_SETBITS(schedsofttq, &idelayed, SWI_TQ_PENDING)
70 softclockpending(void)
72 return (ipending & SWI_CLOCK_PENDING);
76 * Support for SPL assertions.
79 #ifdef INVARIANT_SUPPORT
81 #define SPLASSERT_IGNORE 0
82 #define SPLASSERT_LOG 1
83 #define SPLASSERT_PANIC 2
85 static int splassertmode = SPLASSERT_LOG;
86 SYSCTL_INT(_kern, OID_AUTO, splassertmode, CTLFLAG_RW,
87 &splassertmode, 0, "Set the mode of SPLASSERT");
88 TUNABLE_INT("kern.splassertmode", &splassertmode);
91 splassertfail(char *str, const char *msg, char *name, int level)
93 switch (splassertmode) {
94 case SPLASSERT_IGNORE:
97 printf(str, msg, name, level);
100 case SPLASSERT_PANIC:
101 panic(str, msg, name, level);
106 #define GENSPLASSERT(NAME, MODIFIER) \
108 NAME##assert(const char *msg) \
110 if ((cpl & (MODIFIER)) != (MODIFIER)) \
111 splassertfail("%s: not %s, cpl == %#x", \
112 msg, __XSTRING(NAME) + 3, cpl); \
115 #define GENSPLASSERT(NAME, MODIFIER)
118 /************************************************************************
120 ************************************************************************
122 * Implement splXXX(), spl0(), splx(), and splq(). splXXX() disables a
123 * set of interrupts (e.g. splbio() disables interrupts relating to
124 * device I/O) and returns the previous interrupt mask. splx() restores
125 * the previous interrupt mask, spl0() is a special case which enables
126 * all interrupts and is typically used inside i386/i386 swtch.s and
127 * fork_trampoline. splq() is a generic version of splXXX().
129 * The SPL routines mess around with the 'cpl' global, which masks
130 * interrupts. Interrupts are not *actually* masked. What happens is
131 * that if an interrupt masked by the cpl occurs, the appropriate bit
132 * in 'ipending' is set and the interrupt is defered. When we clear
133 * bits in the cpl we must check to see if any ipending interrupts have
134 * been unmasked and issue the synchronously, which is what the splz()
137 * Because the cpl is often saved and restored in a nested fashion, cpl
138 * modifications are only allowed in the SMP case when the MP lock is held
139 * to prevent multiple processes from tripping over each other's masks.
140 * The cpl is saved when you do a context switch (mi_switch()) and restored
141 * when your process gets cpu again.
143 * An interrupt routine is allowed to modify the cpl as long as it restores
144 * it prior to returning (thus the interrupted mainline code doesn't notice
145 * anything amiss). For the SMP case, the interrupt routine must hold
146 * the MP lock for any cpl manipulation.
148 * Likewise, due to the deterministic nature of cpl modifications, we do
149 * NOT need to use locked instructions to modify it.
154 #define GENSPL(NAME, OP, MODIFIER, PC) \
155 GENSPLASSERT(NAME, MODIFIER) \
156 unsigned NAME(void) \
182 splq(intrmask_t mask)
184 intrmask_t tmp = cpl;
191 #include <machine/smp.h>
192 #include <machine/smptests.h>
197 * Mostly the same as the non-SMP case now, but it didn't used to be
201 #define GENSPL(NAME, OP, MODIFIER, PC) \
202 GENSPLASSERT(NAME, MODIFIER) \
203 unsigned NAME(void) \
214 * spl0() - unmask all interrupts
216 * The MP lock must be held on entry
217 * This routine may only be called from mainline code.
222 KASSERT(inside_intr == 0, ("spl0: called from interrupt"));
229 * splx() - restore previous interrupt mask
231 * The MP lock must be held on entry
238 if (inside_intr == 0 && (ipending & ~cpl) != 0)
244 * splq() - blocks specified interrupts
246 * The MP lock must be held on entry
249 splq(intrmask_t mask)
251 intrmask_t tmp = cpl;
258 /* Finally, generate the actual spl*() functions */
260 /* NAME: OP: MODIFIER: PC: */
261 GENSPL(splbio, |=, bio_imask, 2)
262 GENSPL(splcam, |=, cam_imask, 7)
263 GENSPL(splclock, =, HWI_MASK | SWI_MASK, 3)
264 GENSPL(splhigh, =, HWI_MASK | SWI_MASK, 4)
265 GENSPL(splimp, |=, net_imask, 5)
266 GENSPL(splnet, |=, SWI_NET_MASK, 6)
267 GENSPL(splsoftcam, |=, SWI_CAMBIO_MASK | SWI_CAMNET_MASK, 8)
268 GENSPL(splsoftcambio, |=, SWI_CAMBIO_MASK, 9)
269 GENSPL(splsoftcamnet, |=, SWI_CAMNET_MASK, 10)
270 GENSPL(splsoftclock, =, SWI_CLOCK_MASK, 11)
271 GENSPL(splsofttty, |=, SWI_TTY_MASK, 12)
272 GENSPL(splsoftvm, |=, SWI_VM_MASK, 16)
273 GENSPL(splsofttq, |=, SWI_TQ_MASK, 17)
274 GENSPL(splstatclock, |=, stat_imask, 13)
275 GENSPL(spltty, |=, tty_imask, 14)
276 GENSPL(splvm, |=, net_imask | bio_imask | cam_imask, 15)
277 GENSPL(splcrypto, |=, net_imask | SWI_NET_MASK | SWI_CRYPTO_MASK,16)