freebsd-skq/sys/i386/isa/vector.s

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1993-06-12 14:58:17 +00:00
/*
* from: vector.s, 386BSD 0.1 unknown origin
1999-08-28 01:08:13 +00:00
* $FreeBSD$
*/
/*
* modified for PC98 by Kakefuda
1993-06-12 14:58:17 +00:00
*/
#include "opt_auto_eoi.h"
#include <i386/isa/icu.h>
#ifdef PC98
#include <pc98/pc98/pc98.h>
#else
#include <i386/isa/isa.h>
#endif
#define FAST_INTR_HANDLER_USES_ES 1
New interrupt code from Bruce Evans. In additional to Bruce's attached list of changes, I've made the following additional changes: 1) i386/include/ipl.h renamed to spl.h as the name conflicts with the file of the same name in i386/isa/ipl.h. 2) changed all use of *mask (i.e. netmask, biomask, ttymask, etc) to *_imask (net_imask, etc). 3) changed vestige of splnet use in if_is to splimp. 4) got rid of "impmask" completely (Bruce had gotten rid of netmask), and are now using net_imask instead. 5) dozens of minor cruft to glue in Bruce's changes. These require changes I made to config(8) as well, and thus it must be rebuilt. -DG from Bruce Evans: sio: o No diff is supplied. Remove the define of setsofttty(). I hope that is enough. *.s: o i386/isa/debug.h no longer exists. The event counters became too much trouble to maintain. All function call entry and exception entry counters can be recovered by using profiling kernel (the new profiling supports all entry points; however, it is too slow to leave enabled all the time; it also). Only BDBTRAP() from debug.h is now used. That is moved to exception.s. It might be worth preserving SHOW_BITS() and calling it from _mcount() (if enabled). o T_ASTFLT is now only set just before calling trap(). o All exception handlers set SWI_AST_MASK in cpl as soon as possible after entry and arrange for _doreti to restore it atomically with exiting. It is not possible to set it atomically with entering the kernel, so it must be checked against the user mode bits in the trap frame before committing to using it. There is no place to store the old value of cpl for syscalls or traps, so there are some complications restoring it. Profiling stuff (mostly in *.s): o Changes to kern/subr_mcount.c, gcc and gprof are not supplied yet. o All interesting labels `foo' are renamed `_foo' and all uninteresting labels `_bar' are renamed `bar'. A small change to gprof allows ignoring labels not starting with underscores. o MCOUNT_LABEL() is to provide names for counters for times spent in exception handlers. o FAKE_MCOUNT() is a version of MCOUNT() suitable for exception handlers. Its arg is the pc where the exception occurred. The new mcount() pretends that this was a call from that pc to a suitable MCOUNT_LABEL(). o MEXITCOUNT is to turn off any timer started by MCOUNT(). /usr/src/sys/i386/i386/exception.s: o The non-BDB BPTTRAP() macros were doing a sti even when interrupts were disabled when the trap occurred. The sti (fixed) sti is actually a no-op unless you have my changes to machdep.c that make the debugger trap gates interrupt gates, but fixing that would make the ifdefs messier. ddb seems to be unharmed by both interrupts always disabled and always enabled (I had the branch in the fix back to front for some time :-(). o There is no known pushal bug. o tf_err can be left as garbage for syscalls. /usr/src/sys/i386/i386/locore.s: o Fix and update BDE_DEBUGGER support. o ENTRY(btext) before initialization was dangerous. o Warm boot shot was longer than intended. /usr/src/sys/i386/i386/machdep.c: o DON'T APPLY ALL OF THIS DIFF. It's what I'm using, but may require other changes. Use the following: o Remove aston() and setsoftclock(). Maybe use the following: o No netisr.h. o Spelling fix. o Delay to read the Rebooting message. o Fix for vm system unmapping a reduced area of memory after bounds_check_with_label() reduces the size of a physical i/o for a partition boundary. A similar fix is required in kern_physio.c. o Correct use of __CONCAT. It never worked here for non- ANSI cpp's. Is it time to drop support for non-ANSI? o gdt_segs init. 0xffffffffUL is bogus because ssd_limit is not 32 bits. The replacement may have the same value :-), but is more natural. o physmem was one page too low. Confusing variable names. Don't use the following: o Better numbers of buffers. Each 8K page requires up to 16 buffer headers. On my system, this results in 5576 buffers containing [up to] 2854912 bytes of memory. The usual allocation of about 384 buffers only holds 192K of disk if you use it on an fs with a block size of 512. o gdt changes for bdb. o *TGT -> *IDT changes for bdb. o #ifdefed changes for bdb. /usr/src/sys/i386/i386/microtime.s: o Use the correct asm macros. I think asm.h was copied from Mach just for microtime and isn't used now. It certainly doesn't belong in <sys>. Various macros are also duplicated in sys/i386/boot.h and libc/i386/*.h. o Don't switch to and from the IRR; it is guaranteed to be selected (default after ICU init and explicitly selected in isa.c too, and never changed until the old microtime clobbered it). /usr/src/sys/i386/i386/support.s: o Non-essential changes (none related to spls or profiling). o Removed slow loads of %gs again. The LDT support may require not relying on %gs, but loading it is not the way to fix it! Some places (copyin ...) forgot to load it. Loading it clobbers the user %gs. trap() still loads it after certain types of faults so that fuword() etc can rely on it without loading it explicitly. Exception handlers don't restore it. If we want to preserve the user %gs, then the fastest method is to not touch it except for context switches. Comparing with VM_MAXUSER_ADDRESS and branching takes only 2 or 4 cycles on a 486, while loading %gs takes 9 cycles and using it takes another. o Fixed a signed branch to unsigned. /usr/src/sys/i386/i386/swtch.s: o Move spl0() outside of idle loop. o Remove cli/sti from idle loop. sw1 does a cli, and in the unlikely event of an interrupt occurring and whichqs becoming zero, sw1 will just jump back to _idle. o There's no spl0() function in asm any more, so use splz(). o swtch() doesn't need to be superaligned, at least with the new mcounting. o Fixed a signed branch to unsigned. o Removed astoff(). /usr/src/sys/i386/i386/trap.c: o The decentralized extern decls were inconsistent, of course. o Fixed typo MATH_EMULTATE in comments. */ o Removed unused variables. o Old netmask is now impmask; print it instead. Perhaps we should print some of the new masks. o BTW, trap() should not print anything for normal debugger traps. /usr/src/sys/i386/include/asmacros.h: o DON'T APPLY ALL OF THIS DIFF. Just use some of the null macros as necessary. /usr/src/sys/i386/include/cpu.h: o CLKF_BASEPRI() changes since cpl == SWI_AST_MASK is now normal while the kernel is running. o Don't use var++ to set boolean variables. It fails after a mere 4G times :-) and is slower than storing a constant on [3-4]86s. /usr/src/sys/i386/include/cpufunc.h: o DON'T APPLY ALL OF THIS DIFF. You need mainly the include of <machine/ipl.h>. Unfortunately, <machine/ipl.h> is needed by almost everything for the inlines. /usr/src/sys/i386/include/ipl.h: o New file. Defines spl inlines and SWI macros and declares most variables related to hard and soft interrupt masks. /usr/src/sys/i386/isa/icu.h: o Moved definitions to <machine/ipl.h> /usr/src/sys/i386/isa/icu.s: o Software interrupts (SWIs) and delayed hardware interrupts (HWIs) are now handled uniformally, and dispatching them from splx() is more like dispatching them from _doreti. The dispatcher is essentially *(handler[ffs(ipending & ~cpl)](). o More care (not quite enough) is taken to avoid unbounded nesting of interrupts. o The interface to softclock() is changed so that a trap frame is not required. o Fast interrupt handlers are now handled more uniformally. Configuration is still too early (new handlers would require bits in <machine/ipl.h> and functions to vector.s). o splnnn() and splx() are no longer here; they are inline functions (could be macros for other compilers). splz() is the nontrivial part of the old splx(). /usr/src/sys/i386/isa/ipl.h o New file. Supposed to have only bus-dependent stuff. Perhaps the h/w masks should be declared here. /usr/src/sys/i386/isa/isa.c: o DON'T APPLY ALL OF THIS DIFF. You need only things involving *mask and *MASK and comments about them. netmask is now a pure software mask. It works like the softclock mask. /usr/src/sys/i386/isa/vector.s: o Reorganize AUTO_EOI* macros. o Option FAST_INTR_HANDLER_USERS_ES for people who don't trust fastintr handlers. o fastintr handlers need to metamorphose into ordinary interrupt handlers if their SWI bit has become set. Previously, sio had unintended latency for handling output completions and input of SLIP framing characters because this was not done. /usr/src/sys/net/netisr.h: o The machine-dependent stuff is now imported from <machine/ipl.h>. /usr/src/sys/sys/systm.h o DON'T APPLY ALL OF THIS DIFF. You need mainly the different splx() prototype. The spl*() prototypes are duplicated as inlines in <machine/ipl.h> but they need to be duplicated here in case there are no inlines. I sent systm.h and cpufunc.h to Garrett. We agree that spl0 should be replaced by splnone and not the other way around like I've done. /usr/src/sys/kern/kern_clock.c o splsoftclock() now lowers cpl so the direct call to softclock() works as intended. o softclock() interface changed to avoid passing the whole frame (some machines may need another change for profile_tick()). o profiling renamed _profiling to avoid ANSI namespace pollution. (I had to improve the mcount() interface and may as well fix it.) The GUPROF variant doesn't actually reference profiling here, but the 'U' in GUPROF should mean to select the microtimer mcount() and not change the interface.
1994-04-02 07:00:53 +00:00
#ifdef FAST_INTR_HANDLER_USES_ES
#define ACTUALLY_PUSHED 1
#define MAYBE_MOVW_AX_ES movw %ax,%es
New interrupt code from Bruce Evans. In additional to Bruce's attached list of changes, I've made the following additional changes: 1) i386/include/ipl.h renamed to spl.h as the name conflicts with the file of the same name in i386/isa/ipl.h. 2) changed all use of *mask (i.e. netmask, biomask, ttymask, etc) to *_imask (net_imask, etc). 3) changed vestige of splnet use in if_is to splimp. 4) got rid of "impmask" completely (Bruce had gotten rid of netmask), and are now using net_imask instead. 5) dozens of minor cruft to glue in Bruce's changes. These require changes I made to config(8) as well, and thus it must be rebuilt. -DG from Bruce Evans: sio: o No diff is supplied. Remove the define of setsofttty(). I hope that is enough. *.s: o i386/isa/debug.h no longer exists. The event counters became too much trouble to maintain. All function call entry and exception entry counters can be recovered by using profiling kernel (the new profiling supports all entry points; however, it is too slow to leave enabled all the time; it also). Only BDBTRAP() from debug.h is now used. That is moved to exception.s. It might be worth preserving SHOW_BITS() and calling it from _mcount() (if enabled). o T_ASTFLT is now only set just before calling trap(). o All exception handlers set SWI_AST_MASK in cpl as soon as possible after entry and arrange for _doreti to restore it atomically with exiting. It is not possible to set it atomically with entering the kernel, so it must be checked against the user mode bits in the trap frame before committing to using it. There is no place to store the old value of cpl for syscalls or traps, so there are some complications restoring it. Profiling stuff (mostly in *.s): o Changes to kern/subr_mcount.c, gcc and gprof are not supplied yet. o All interesting labels `foo' are renamed `_foo' and all uninteresting labels `_bar' are renamed `bar'. A small change to gprof allows ignoring labels not starting with underscores. o MCOUNT_LABEL() is to provide names for counters for times spent in exception handlers. o FAKE_MCOUNT() is a version of MCOUNT() suitable for exception handlers. Its arg is the pc where the exception occurred. The new mcount() pretends that this was a call from that pc to a suitable MCOUNT_LABEL(). o MEXITCOUNT is to turn off any timer started by MCOUNT(). /usr/src/sys/i386/i386/exception.s: o The non-BDB BPTTRAP() macros were doing a sti even when interrupts were disabled when the trap occurred. The sti (fixed) sti is actually a no-op unless you have my changes to machdep.c that make the debugger trap gates interrupt gates, but fixing that would make the ifdefs messier. ddb seems to be unharmed by both interrupts always disabled and always enabled (I had the branch in the fix back to front for some time :-(). o There is no known pushal bug. o tf_err can be left as garbage for syscalls. /usr/src/sys/i386/i386/locore.s: o Fix and update BDE_DEBUGGER support. o ENTRY(btext) before initialization was dangerous. o Warm boot shot was longer than intended. /usr/src/sys/i386/i386/machdep.c: o DON'T APPLY ALL OF THIS DIFF. It's what I'm using, but may require other changes. Use the following: o Remove aston() and setsoftclock(). Maybe use the following: o No netisr.h. o Spelling fix. o Delay to read the Rebooting message. o Fix for vm system unmapping a reduced area of memory after bounds_check_with_label() reduces the size of a physical i/o for a partition boundary. A similar fix is required in kern_physio.c. o Correct use of __CONCAT. It never worked here for non- ANSI cpp's. Is it time to drop support for non-ANSI? o gdt_segs init. 0xffffffffUL is bogus because ssd_limit is not 32 bits. The replacement may have the same value :-), but is more natural. o physmem was one page too low. Confusing variable names. Don't use the following: o Better numbers of buffers. Each 8K page requires up to 16 buffer headers. On my system, this results in 5576 buffers containing [up to] 2854912 bytes of memory. The usual allocation of about 384 buffers only holds 192K of disk if you use it on an fs with a block size of 512. o gdt changes for bdb. o *TGT -> *IDT changes for bdb. o #ifdefed changes for bdb. /usr/src/sys/i386/i386/microtime.s: o Use the correct asm macros. I think asm.h was copied from Mach just for microtime and isn't used now. It certainly doesn't belong in <sys>. Various macros are also duplicated in sys/i386/boot.h and libc/i386/*.h. o Don't switch to and from the IRR; it is guaranteed to be selected (default after ICU init and explicitly selected in isa.c too, and never changed until the old microtime clobbered it). /usr/src/sys/i386/i386/support.s: o Non-essential changes (none related to spls or profiling). o Removed slow loads of %gs again. The LDT support may require not relying on %gs, but loading it is not the way to fix it! Some places (copyin ...) forgot to load it. Loading it clobbers the user %gs. trap() still loads it after certain types of faults so that fuword() etc can rely on it without loading it explicitly. Exception handlers don't restore it. If we want to preserve the user %gs, then the fastest method is to not touch it except for context switches. Comparing with VM_MAXUSER_ADDRESS and branching takes only 2 or 4 cycles on a 486, while loading %gs takes 9 cycles and using it takes another. o Fixed a signed branch to unsigned. /usr/src/sys/i386/i386/swtch.s: o Move spl0() outside of idle loop. o Remove cli/sti from idle loop. sw1 does a cli, and in the unlikely event of an interrupt occurring and whichqs becoming zero, sw1 will just jump back to _idle. o There's no spl0() function in asm any more, so use splz(). o swtch() doesn't need to be superaligned, at least with the new mcounting. o Fixed a signed branch to unsigned. o Removed astoff(). /usr/src/sys/i386/i386/trap.c: o The decentralized extern decls were inconsistent, of course. o Fixed typo MATH_EMULTATE in comments. */ o Removed unused variables. o Old netmask is now impmask; print it instead. Perhaps we should print some of the new masks. o BTW, trap() should not print anything for normal debugger traps. /usr/src/sys/i386/include/asmacros.h: o DON'T APPLY ALL OF THIS DIFF. Just use some of the null macros as necessary. /usr/src/sys/i386/include/cpu.h: o CLKF_BASEPRI() changes since cpl == SWI_AST_MASK is now normal while the kernel is running. o Don't use var++ to set boolean variables. It fails after a mere 4G times :-) and is slower than storing a constant on [3-4]86s. /usr/src/sys/i386/include/cpufunc.h: o DON'T APPLY ALL OF THIS DIFF. You need mainly the include of <machine/ipl.h>. Unfortunately, <machine/ipl.h> is needed by almost everything for the inlines. /usr/src/sys/i386/include/ipl.h: o New file. Defines spl inlines and SWI macros and declares most variables related to hard and soft interrupt masks. /usr/src/sys/i386/isa/icu.h: o Moved definitions to <machine/ipl.h> /usr/src/sys/i386/isa/icu.s: o Software interrupts (SWIs) and delayed hardware interrupts (HWIs) are now handled uniformally, and dispatching them from splx() is more like dispatching them from _doreti. The dispatcher is essentially *(handler[ffs(ipending & ~cpl)](). o More care (not quite enough) is taken to avoid unbounded nesting of interrupts. o The interface to softclock() is changed so that a trap frame is not required. o Fast interrupt handlers are now handled more uniformally. Configuration is still too early (new handlers would require bits in <machine/ipl.h> and functions to vector.s). o splnnn() and splx() are no longer here; they are inline functions (could be macros for other compilers). splz() is the nontrivial part of the old splx(). /usr/src/sys/i386/isa/ipl.h o New file. Supposed to have only bus-dependent stuff. Perhaps the h/w masks should be declared here. /usr/src/sys/i386/isa/isa.c: o DON'T APPLY ALL OF THIS DIFF. You need only things involving *mask and *MASK and comments about them. netmask is now a pure software mask. It works like the softclock mask. /usr/src/sys/i386/isa/vector.s: o Reorganize AUTO_EOI* macros. o Option FAST_INTR_HANDLER_USERS_ES for people who don't trust fastintr handlers. o fastintr handlers need to metamorphose into ordinary interrupt handlers if their SWI bit has become set. Previously, sio had unintended latency for handling output completions and input of SLIP framing characters because this was not done. /usr/src/sys/net/netisr.h: o The machine-dependent stuff is now imported from <machine/ipl.h>. /usr/src/sys/sys/systm.h o DON'T APPLY ALL OF THIS DIFF. You need mainly the different splx() prototype. The spl*() prototypes are duplicated as inlines in <machine/ipl.h> but they need to be duplicated here in case there are no inlines. I sent systm.h and cpufunc.h to Garrett. We agree that spl0 should be replaced by splnone and not the other way around like I've done. /usr/src/sys/kern/kern_clock.c o splsoftclock() now lowers cpl so the direct call to softclock() works as intended. o softclock() interface changed to avoid passing the whole frame (some machines may need another change for profile_tick()). o profiling renamed _profiling to avoid ANSI namespace pollution. (I had to improve the mcount() interface and may as well fix it.) The GUPROF variant doesn't actually reference profiling here, but the 'U' in GUPROF should mean to select the microtimer mcount() and not change the interface.
1994-04-02 07:00:53 +00:00
#define MAYBE_POPL_ES popl %es
#define MAYBE_PUSHL_ES pushl %es
#else
/*
* We can usually skip loading %es for fastintr handlers. %es should
* only be used for string instructions, and fastintr handlers shouldn't
* do anything slow enough to justify using a string instruction.
*/
#define ACTUALLY_PUSHED 0
#define MAYBE_MOVW_AX_ES
#define MAYBE_POPL_ES
#define MAYBE_PUSHL_ES
1993-06-12 14:58:17 +00:00
#endif
.data
ALIGN_DATA
/*
* Interrupt counters and names for export to vmstat(8) and friends.
*
* XXX this doesn't really belong here; everything except the labels
* for the endpointers is almost machine-independent.
*/
.globl intrcnt, eintrcnt
intrcnt:
.space INTRCNT_COUNT * 4
eintrcnt:
.globl intrnames, eintrnames
intrnames:
.space INTRCNT_COUNT * 16
eintrnames:
.text
1993-06-12 14:58:17 +00:00
/*
* Macros for interrupt interrupt entry, call to handler, and exit.
*
* XXX - the interrupt frame is set up to look like a trap frame. This is
* usually a waste of time. The only interrupt handlers that want a frame
* are the clock handler (it wants a clock frame), the npx handler (it's
* easier to do right all in assembler). The interrupt return routine
* needs a trap frame for rare AST's (it could easily convert the frame).
* The direct costs of setting up a trap frame are two pushl's (error
* code and trap number), an addl to get rid of these, and pushing and
* popping the call-saved regs %esi, %edi and %ebp twice, The indirect
* costs are making the driver interface nonuniform so unpending of
* interrupts is more complicated and slower (call_driver(unit) would
* be easier than ensuring an interrupt frame for all handlers. Finally,
* there are some struct copies in the npx handler and maybe in the clock
* handler that could be avoided by working more with pointers to frames
* instead of frames.
*
* XXX - should we do a cld on every system entry to avoid the requirement
* for scattered cld's?
*
* Coding notes for *.s:
*
* If possible, avoid operations that involve an operand size override.
* Word-sized operations might be smaller, but the operand size override
* makes them slower on on 486's and no faster on 386's unless perhaps
* the instruction pipeline is depleted. E.g.,
*
* Use movl to seg regs instead of the equivalent but more descriptive
* movw - gas generates an irelevant (slower) operand size override.
*
* Use movl to ordinary regs in preference to movw and especially
* in preference to movz[bw]l. Use unsigned (long) variables with the
* top bits clear instead of unsigned short variables to provide more
* opportunities for movl.
*
* If possible, use byte-sized operations. They are smaller and no slower.
*
* Use (%reg) instead of 0(%reg) - gas generates larger code for the latter.
*
* If the interrupt frame is made more flexible, INTR can push %eax first
* and decide the ipending case with less overhead, e.g., by avoiding
* loading segregs.
*/
#ifdef APIC_IO
#include "i386/isa/apic_vector.s"
#else
#include "i386/isa/icu_vector.s"
#endif /* APIC_IO */