freebsd-dev/sys/i386/include/profile.h

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/*-
* SPDX-License-Identifier: BSD-3-Clause
*
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* Copyright (c) 1992, 1993
* 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. Neither the name of the University nor the names of its contributors
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* 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.
*
* @(#)profile.h 8.1 (Berkeley) 6/11/93
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* $FreeBSD$
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*/
#ifndef _MACHINE_PROFILE_H_
#define _MACHINE_PROFILE_H_
#ifndef _SYS_CDEFS_H_
#error this file needs sys/cdefs.h as a prerequisite
#endif
#ifdef _KERNEL
/*
* Config generates something to tell the compiler to align functions on 16
* byte boundaries. A strict alignment is good for keeping the tables small.
*/
#define FUNCTION_ALIGNMENT 16
/*
* The kernel uses assembler stubs instead of unportable inlines.
* This is mainly to save a little time when profiling is not enabled,
* which is the usual case for the kernel.
*/
#define _MCOUNT_DECL void mcount
#define MCOUNT
#ifdef GUPROF
#define MCOUNT_DECL(s)
#define MCOUNT_ENTER(s)
#define MCOUNT_EXIT(s)
#ifdef __GNUCLIKE_ASM
#define MCOUNT_OVERHEAD(label) \
__asm __volatile("pushl %0; call __mcount; popl %%ecx" \
: \
: "i" (label) \
: "ax", "dx", "cx", "memory")
#define MEXITCOUNT_OVERHEAD() \
__asm __volatile("call .mexitcount; 1:" \
: : \
: "cx", "memory")
#define MEXITCOUNT_OVERHEAD_GETLABEL(labelp) \
__asm __volatile("movl $1b,%0" : "=rm" (labelp))
#else
#error
#endif /* !__GNUCLIKE_ASM */
#else /* !GUPROF */
#define MCOUNT_DECL(s) register_t s;
#ifdef SMP
extern int mcount_lock;
#define MCOUNT_ENTER(s) { s = intr_disable(); \
while (!atomic_cmpset_acq_int(&mcount_lock, 0, 1)) \
/* nothing */ ; }
#define MCOUNT_EXIT(s) { atomic_store_rel_int(&mcount_lock, 0); \
intr_restore(s); }
#else
#define MCOUNT_ENTER(s) { s = intr_disable(); }
#define MCOUNT_EXIT(s) (intr_restore(s))
#endif
#endif /* GUPROF */
void bintr(void);
void btrap(void);
void eintr(void);
Fix recent breakages of kernel profiling, mostly on i386 (high resolution kernel profiling remains broken). memmove() was broken using ALTENTRY(). ALTENTRY() is only different from ENTRY() in the profiling case, and its use in that case was sort of backwards. The backwardness magically turned memmove() into memcpy() instead of completely breaking it. Only the high resolution parts of profiling itself were broken. Use ordinary ENTRY() for memmove(). Turn bcopy() into a tail call to memmove() to reduce complications. This gives slightly different pessimizations and profiling lossage. The pessimizations are minimized by not using a frame pointer() for bcopy(). Calls to profiling functions from exception trampolines were not relocated. This caused crashes on the first exception. Fix this using function pointers. Addresses of exception handlers in trampolines were not relocated. This caused unknown offsets in the profiling data. Relocate by abusing setidt_disp as for pmc although this is slower than necessary and requires namespace pollution. pmc seems to be missing some relocations. Stack traces and lots of other things in debuggers need similar relocations. Most user addresses were misclassified as unknown kernel addresses and then ignored. Treat all unknown addresses as user. Now only user addresses in the kernel text range are significantly misclassified (as known kernel addresses). The ibrs functions didn't preserve enough registers. This is the only recent breakage on amd64. Although these functions are written in asm, in the profiling case they call profiling functions which are mostly for the C ABI, so they only have to save call-used registers. They also have to save arg and return registers in some cases and actually save them in all cases to reduce complications. They end up saving all registers except %ecx on i386 and %r10 and %r11 on amd64. Saving these is only needed for 1 caller on each of amd64 and i386. Save them there. This is slightly simpler. Remove saving %ecx in handle_ibrs_exit on i386. Both handle_ibrs_entry and handle_ibrs_exit use %ecx, but only the latter needed to or did save it. But saving it there doesn't work for the profiling case. amd64 has more automatic saving of the most common scratch registers %rax, %rcx and %rdx (its complications for %r10 are from unusual use of %r10 by SYSCALL). Thus profiling of handle_ibrs_exit_rs() was not broken, and I didn't simplify the saving by moving the saving of these registers from it to the caller.
2018-06-02 04:25:09 +00:00
#if 0
void end_exceptions(void);
void start_exceptions(void);
#else
#include <machine/pmc_mdep.h> /* XXX */
#endif
void user(void);
Fix recent breakages of kernel profiling, mostly on i386 (high resolution kernel profiling remains broken). memmove() was broken using ALTENTRY(). ALTENTRY() is only different from ENTRY() in the profiling case, and its use in that case was sort of backwards. The backwardness magically turned memmove() into memcpy() instead of completely breaking it. Only the high resolution parts of profiling itself were broken. Use ordinary ENTRY() for memmove(). Turn bcopy() into a tail call to memmove() to reduce complications. This gives slightly different pessimizations and profiling lossage. The pessimizations are minimized by not using a frame pointer() for bcopy(). Calls to profiling functions from exception trampolines were not relocated. This caused crashes on the first exception. Fix this using function pointers. Addresses of exception handlers in trampolines were not relocated. This caused unknown offsets in the profiling data. Relocate by abusing setidt_disp as for pmc although this is slower than necessary and requires namespace pollution. pmc seems to be missing some relocations. Stack traces and lots of other things in debuggers need similar relocations. Most user addresses were misclassified as unknown kernel addresses and then ignored. Treat all unknown addresses as user. Now only user addresses in the kernel text range are significantly misclassified (as known kernel addresses). The ibrs functions didn't preserve enough registers. This is the only recent breakage on amd64. Although these functions are written in asm, in the profiling case they call profiling functions which are mostly for the C ABI, so they only have to save call-used registers. They also have to save arg and return registers in some cases and actually save them in all cases to reduce complications. They end up saving all registers except %ecx on i386 and %r10 and %r11 on amd64. Saving these is only needed for 1 caller on each of amd64 and i386. Save them there. This is slightly simpler. Remove saving %ecx in handle_ibrs_exit on i386. Both handle_ibrs_entry and handle_ibrs_exit use %ecx, but only the latter needed to or did save it. But saving it there doesn't work for the profiling case. amd64 has more automatic saving of the most common scratch registers %rax, %rcx and %rdx (its complications for %r10 are from unusual use of %r10 by SYSCALL). Thus profiling of handle_ibrs_exit_rs() was not broken, and I didn't simplify the saving by moving the saving of these registers from it to the caller.
2018-06-02 04:25:09 +00:00
#include <machine/md_var.h> /* XXX for setidt_disp */
#define MCOUNT_DETRAMP(pc) do { \
if ((pc) >= (uintfptr_t)start_exceptions + setidt_disp && \
(pc) < (uintfptr_t)end_exceptions + setidt_disp) \
(pc) -= setidt_disp; \
} while (0)
#define MCOUNT_FROMPC_INTR(pc) \
((pc >= (uintfptr_t)btrap && pc < (uintfptr_t)eintr) ? \
((pc >= (uintfptr_t)bintr) ? (uintfptr_t)bintr : \
(uintfptr_t)btrap) : ~0U)
Fix recent breakages of kernel profiling, mostly on i386 (high resolution kernel profiling remains broken). memmove() was broken using ALTENTRY(). ALTENTRY() is only different from ENTRY() in the profiling case, and its use in that case was sort of backwards. The backwardness magically turned memmove() into memcpy() instead of completely breaking it. Only the high resolution parts of profiling itself were broken. Use ordinary ENTRY() for memmove(). Turn bcopy() into a tail call to memmove() to reduce complications. This gives slightly different pessimizations and profiling lossage. The pessimizations are minimized by not using a frame pointer() for bcopy(). Calls to profiling functions from exception trampolines were not relocated. This caused crashes on the first exception. Fix this using function pointers. Addresses of exception handlers in trampolines were not relocated. This caused unknown offsets in the profiling data. Relocate by abusing setidt_disp as for pmc although this is slower than necessary and requires namespace pollution. pmc seems to be missing some relocations. Stack traces and lots of other things in debuggers need similar relocations. Most user addresses were misclassified as unknown kernel addresses and then ignored. Treat all unknown addresses as user. Now only user addresses in the kernel text range are significantly misclassified (as known kernel addresses). The ibrs functions didn't preserve enough registers. This is the only recent breakage on amd64. Although these functions are written in asm, in the profiling case they call profiling functions which are mostly for the C ABI, so they only have to save call-used registers. They also have to save arg and return registers in some cases and actually save them in all cases to reduce complications. They end up saving all registers except %ecx on i386 and %r10 and %r11 on amd64. Saving these is only needed for 1 caller on each of amd64 and i386. Save them there. This is slightly simpler. Remove saving %ecx in handle_ibrs_exit on i386. Both handle_ibrs_entry and handle_ibrs_exit use %ecx, but only the latter needed to or did save it. But saving it there doesn't work for the profiling case. amd64 has more automatic saving of the most common scratch registers %rax, %rcx and %rdx (its complications for %r10 are from unusual use of %r10 by SYSCALL). Thus profiling of handle_ibrs_exit_rs() was not broken, and I didn't simplify the saving by moving the saving of these registers from it to the caller.
2018-06-02 04:25:09 +00:00
#define MCOUNT_USERPC ((uintfptr_t)user)
#else /* !_KERNEL */
#define FUNCTION_ALIGNMENT 4
#define _MCOUNT_DECL static __inline void _mcount
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#ifdef __GNUCLIKE_ASM
#define MCOUNT \
void \
mcount() \
{ \
uintfptr_t selfpc, frompc, ecx; \
/* \
* In gcc 4.2, ecx might be used in the caller as the arg \
* pointer if the stack realignment option is set (-mstackrealign) \
* or if the caller has the force_align_arg_pointer attribute \
* (stack realignment is ALWAYS on for main). Preserve ecx \
* here. \
*/ \
__asm("" : "=c" (ecx)); \
/* \
* Find the return address for mcount, \
* and the return address for mcount's caller. \
* \
* selfpc = pc pushed by call to mcount \
*/ \
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__asm("movl 4(%%ebp),%0" : "=r" (selfpc)); \
/* \
* frompc = pc pushed by call to mcount's caller. \
* The caller's stack frame has already been built, so %ebp is \
* the caller's frame pointer. The caller's raddr is in the \
* caller's frame following the caller's caller's frame pointer.\
*/ \
__asm("movl (%%ebp),%0" : "=r" (frompc)); \
frompc = ((uintfptr_t *)frompc)[1]; \
_mcount(frompc, selfpc); \
__asm("" : : "c" (ecx)); \
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}
#else /* !__GNUCLIKE_ASM */
#define MCOUNT
#endif /* __GNUCLIKE_ASM */
typedef u_int uintfptr_t;
#endif /* _KERNEL */
/*
* An unsigned integral type that can hold non-negative difference between
* function pointers.
*/
typedef u_int fptrdiff_t;
#ifdef _KERNEL
Improved non-statistical (GUPROF) profiling: - use a more accurate and more efficient method of compensating for overheads. The old method counted too much time against leaf functions. - normally use the Pentium timestamp counter if available. On Pentiums, the times are now accurate to within a couple of cpu clock cycles per function call in the (unlikely) event that there are no cache misses in or caused by the profiling code. - optionally use an arbitrary Pentium event counter if available. - optionally regress to using the i8254 counter. - scaled the i8254 counter by a factor of 128. Now the i8254 counters overflow slightly faster than the TSC counters for a 150MHz Pentium :-) (after about 16 seconds). This is to avoid fractional overheads. files.i386: permon.c temporarily has to be classified as a profiling-routine because a couple of functions in it may be called from profiling code. options.i386: - I586_CTR_GUPROF is currently unused (oops). - I586_PMC_GUPROF should be something like 0x70000 to enable (but not use unless prof_machdep.c is changed) support for Pentium event counters. 7 is a control mode and the counter number 0 is somewhere in the 0000 bits (see perfmon.h for the encoding). profile.h: - added declarations. - cleaned up separation of user mode declarations. prof_machdep.c: Mostly clock-select changes. The default clock can be changed by editing kmem. There should be a sysctl for this. subr_prof.c: - added copyright. - calibrate overheads for the new method. - documented new method. - fixed races and and machine dependencies in start/stop code. mcount.c: Use the new overhead compensation method. gmon.h: - changed GPROF4 counter type from unsigned to int. Oops, this should be machine-dependent and/or int32_t. - reorganized overhead counters. Submitted by: Pentium event counter changes mostly by wollman
1996-10-17 19:32:31 +00:00
2002-03-20 05:48:58 +00:00
void mcount(uintfptr_t frompc, uintfptr_t selfpc);
Improved non-statistical (GUPROF) profiling: - use a more accurate and more efficient method of compensating for overheads. The old method counted too much time against leaf functions. - normally use the Pentium timestamp counter if available. On Pentiums, the times are now accurate to within a couple of cpu clock cycles per function call in the (unlikely) event that there are no cache misses in or caused by the profiling code. - optionally use an arbitrary Pentium event counter if available. - optionally regress to using the i8254 counter. - scaled the i8254 counter by a factor of 128. Now the i8254 counters overflow slightly faster than the TSC counters for a 150MHz Pentium :-) (after about 16 seconds). This is to avoid fractional overheads. files.i386: permon.c temporarily has to be classified as a profiling-routine because a couple of functions in it may be called from profiling code. options.i386: - I586_CTR_GUPROF is currently unused (oops). - I586_PMC_GUPROF should be something like 0x70000 to enable (but not use unless prof_machdep.c is changed) support for Pentium event counters. 7 is a control mode and the counter number 0 is somewhere in the 0000 bits (see perfmon.h for the encoding). profile.h: - added declarations. - cleaned up separation of user mode declarations. prof_machdep.c: Mostly clock-select changes. The default clock can be changed by editing kmem. There should be a sysctl for this. subr_prof.c: - added copyright. - calibrate overheads for the new method. - documented new method. - fixed races and and machine dependencies in start/stop code. mcount.c: Use the new overhead compensation method. gmon.h: - changed GPROF4 counter type from unsigned to int. Oops, this should be machine-dependent and/or int32_t. - reorganized overhead counters. Submitted by: Pentium event counter changes mostly by wollman
1996-10-17 19:32:31 +00:00
#else /* !_KERNEL */
Improved non-statistical (GUPROF) profiling: - use a more accurate and more efficient method of compensating for overheads. The old method counted too much time against leaf functions. - normally use the Pentium timestamp counter if available. On Pentiums, the times are now accurate to within a couple of cpu clock cycles per function call in the (unlikely) event that there are no cache misses in or caused by the profiling code. - optionally use an arbitrary Pentium event counter if available. - optionally regress to using the i8254 counter. - scaled the i8254 counter by a factor of 128. Now the i8254 counters overflow slightly faster than the TSC counters for a 150MHz Pentium :-) (after about 16 seconds). This is to avoid fractional overheads. files.i386: permon.c temporarily has to be classified as a profiling-routine because a couple of functions in it may be called from profiling code. options.i386: - I586_CTR_GUPROF is currently unused (oops). - I586_PMC_GUPROF should be something like 0x70000 to enable (but not use unless prof_machdep.c is changed) support for Pentium event counters. 7 is a control mode and the counter number 0 is somewhere in the 0000 bits (see perfmon.h for the encoding). profile.h: - added declarations. - cleaned up separation of user mode declarations. prof_machdep.c: Mostly clock-select changes. The default clock can be changed by editing kmem. There should be a sysctl for this. subr_prof.c: - added copyright. - calibrate overheads for the new method. - documented new method. - fixed races and and machine dependencies in start/stop code. mcount.c: Use the new overhead compensation method. gmon.h: - changed GPROF4 counter type from unsigned to int. Oops, this should be machine-dependent and/or int32_t. - reorganized overhead counters. Submitted by: Pentium event counter changes mostly by wollman
1996-10-17 19:32:31 +00:00
#include <sys/cdefs.h>
__BEGIN_DECLS
#ifdef __GNUCLIKE_ASM
2002-03-20 05:48:58 +00:00
void mcount(void) __asm(".mcount");
#endif
Improved non-statistical (GUPROF) profiling: - use a more accurate and more efficient method of compensating for overheads. The old method counted too much time against leaf functions. - normally use the Pentium timestamp counter if available. On Pentiums, the times are now accurate to within a couple of cpu clock cycles per function call in the (unlikely) event that there are no cache misses in or caused by the profiling code. - optionally use an arbitrary Pentium event counter if available. - optionally regress to using the i8254 counter. - scaled the i8254 counter by a factor of 128. Now the i8254 counters overflow slightly faster than the TSC counters for a 150MHz Pentium :-) (after about 16 seconds). This is to avoid fractional overheads. files.i386: permon.c temporarily has to be classified as a profiling-routine because a couple of functions in it may be called from profiling code. options.i386: - I586_CTR_GUPROF is currently unused (oops). - I586_PMC_GUPROF should be something like 0x70000 to enable (but not use unless prof_machdep.c is changed) support for Pentium event counters. 7 is a control mode and the counter number 0 is somewhere in the 0000 bits (see perfmon.h for the encoding). profile.h: - added declarations. - cleaned up separation of user mode declarations. prof_machdep.c: Mostly clock-select changes. The default clock can be changed by editing kmem. There should be a sysctl for this. subr_prof.c: - added copyright. - calibrate overheads for the new method. - documented new method. - fixed races and and machine dependencies in start/stop code. mcount.c: Use the new overhead compensation method. gmon.h: - changed GPROF4 counter type from unsigned to int. Oops, this should be machine-dependent and/or int32_t. - reorganized overhead counters. Submitted by: Pentium event counter changes mostly by wollman
1996-10-17 19:32:31 +00:00
__END_DECLS
#endif /* _KERNEL */
#endif /* !_MACHINE_PROFILE_H_ */