newlib/winsup/cygwin/mcount.c

180 lines
5.4 KiB
C
Raw Normal View History

2000-02-17 20:38:33 +01:00
/*-
* Copyright (c) 1983, 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.
* 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.
*/
#if !defined(lint) && !defined(_KERNEL) && defined(LIBC_SCCS)
static char rcsid[] = "$OpenBSD: mcount.c,v 1.6 1997/07/23 21:11:27 kstailey Exp $";
#endif
/*
* This file is taken from Cygwin distribution. Please keep it in sync.
* The differences should be within __MINGW32__ guard.
*/
#ifndef __MINGW32__
#include <sys/param.h>
#endif
2000-02-17 20:38:33 +01:00
#include <sys/types.h>
#include "gmon.h"
Support profiling of multi-threaded apps. This patch set modifies Cygwin's profiling support to sample PC values of all an app's threads, not just the main thread. There is no change to how profiling is requested: just compile and link the app with "-pg" as usual. The profiling info is dumped into file gmon.out as always. A new facility enabled via the environment variable GMON_OUT_PREFIX. This facility is intended to match an undocumented Linux glibc feature. Exporting the variable with a non-empty value such as "foo" causes the profiling info to go to a file named foo.$pid instead of the default. With that, both resulting processes of a fork() can have their profiling data captured in separate files. gprof already knows how to accumulate data from multiple files if they all pertain to the same app. There is no change to the normal Cygwin execution paths if profiling is not enabled. And when it is enabled, only the one profiling thread per profiled app is doing more work than it used to. * include/sys/cygwin.h: Add CW_CYGHEAP_PROFTHR_ALL. * cygheap.cc (cygheap_profthr_all): New C-callable function that runs cygheap's threadlist handing each pthread's thread handle in turn to profthr_byhandle(). * external.cc (cygwin_internal): Add case CW_CYGHEAP_PROFTHR_ALL. * gmon.c (_mcleanup): Add support for multiple simultaneous gmon.out* files named via environment variable GMON_OUT_PREFIX. * gmon.h (struct gmonparam): Make state decl volatile. * mcount.c (_MCOUNT_DECL): Change stores into gmonparam.state to use Interlocked operations. Add #include "winsup.h", update commentary. * profil.c (profthr_byhandle): New function abstracting out the updating of profile counters based on a thread handle. (profthr_func): Update to call profthr_byhandle() to sample the main thread then call cygheap_profthr_all() indirectly through cygwin_internal(CW_CYGHEAP_PROFTHR_ALL) to sample all other threads. (profile_off): Zero targthr to indicate profiling was turned off. (profile_on): Fix handle leak on failure path. (profile_child): New callback func to restart profiling in child process after a fork if the parent was being profiled. (profile_ctl): Call pthread_atfork() to set profile_child callback. Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2016-02-20 07:58:31 +01:00
#include "winsup.h"
2000-02-17 20:38:33 +01:00
/*
* mcount is called on entry to each function compiled with the profiling
* switch set. _mcount(), which is declared in a machine-dependent way
* with _MCOUNT_DECL, does the actual work and is either inlined into a
* C routine or called by an assembly stub. In any case, this magic is
* taken care of by the MCOUNT definition in <machine/profile.h>.
*
* _mcount updates data structures that represent traversals of the
* program's call graph edges. frompc and selfpc are the return
* address and function address that represents the given call graph edge.
*
* Note: the original BSD code used the same variable (frompcindex) for
* both frompcindex and frompc. Any reasonable, modern compiler will
* perform this optimization.
*/
/* _mcount; may be static, inline, etc */
_MCOUNT_DECL (size_t, size_t);
_MCOUNT_DECL (size_t frompc, size_t selfpc)
2000-02-17 20:38:33 +01:00
{
register u_int16_t *frompcindex;
2000-02-17 20:38:33 +01:00
register struct tostruct *top, *prevtop;
register struct gmonparam *p;
register long toindex;
p = &_gmonparam;
/*
* check that we are profiling
Support profiling of multi-threaded apps. This patch set modifies Cygwin's profiling support to sample PC values of all an app's threads, not just the main thread. There is no change to how profiling is requested: just compile and link the app with "-pg" as usual. The profiling info is dumped into file gmon.out as always. A new facility enabled via the environment variable GMON_OUT_PREFIX. This facility is intended to match an undocumented Linux glibc feature. Exporting the variable with a non-empty value such as "foo" causes the profiling info to go to a file named foo.$pid instead of the default. With that, both resulting processes of a fork() can have their profiling data captured in separate files. gprof already knows how to accumulate data from multiple files if they all pertain to the same app. There is no change to the normal Cygwin execution paths if profiling is not enabled. And when it is enabled, only the one profiling thread per profiled app is doing more work than it used to. * include/sys/cygwin.h: Add CW_CYGHEAP_PROFTHR_ALL. * cygheap.cc (cygheap_profthr_all): New C-callable function that runs cygheap's threadlist handing each pthread's thread handle in turn to profthr_byhandle(). * external.cc (cygwin_internal): Add case CW_CYGHEAP_PROFTHR_ALL. * gmon.c (_mcleanup): Add support for multiple simultaneous gmon.out* files named via environment variable GMON_OUT_PREFIX. * gmon.h (struct gmonparam): Make state decl volatile. * mcount.c (_MCOUNT_DECL): Change stores into gmonparam.state to use Interlocked operations. Add #include "winsup.h", update commentary. * profil.c (profthr_byhandle): New function abstracting out the updating of profile counters based on a thread handle. (profthr_func): Update to call profthr_byhandle() to sample the main thread then call cygheap_profthr_all() indirectly through cygwin_internal(CW_CYGHEAP_PROFTHR_ALL) to sample all other threads. (profile_off): Zero targthr to indicate profiling was turned off. (profile_on): Fix handle leak on failure path. (profile_child): New callback func to restart profiling in child process after a fork if the parent was being profiled. (profile_ctl): Call pthread_atfork() to set profile_child callback. Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2016-02-20 07:58:31 +01:00
* and that we aren't recursively invoked by this thread
* or entered anew by any other thread.
2000-02-17 20:38:33 +01:00
*/
Support profiling of multi-threaded apps. This patch set modifies Cygwin's profiling support to sample PC values of all an app's threads, not just the main thread. There is no change to how profiling is requested: just compile and link the app with "-pg" as usual. The profiling info is dumped into file gmon.out as always. A new facility enabled via the environment variable GMON_OUT_PREFIX. This facility is intended to match an undocumented Linux glibc feature. Exporting the variable with a non-empty value such as "foo" causes the profiling info to go to a file named foo.$pid instead of the default. With that, both resulting processes of a fork() can have their profiling data captured in separate files. gprof already knows how to accumulate data from multiple files if they all pertain to the same app. There is no change to the normal Cygwin execution paths if profiling is not enabled. And when it is enabled, only the one profiling thread per profiled app is doing more work than it used to. * include/sys/cygwin.h: Add CW_CYGHEAP_PROFTHR_ALL. * cygheap.cc (cygheap_profthr_all): New C-callable function that runs cygheap's threadlist handing each pthread's thread handle in turn to profthr_byhandle(). * external.cc (cygwin_internal): Add case CW_CYGHEAP_PROFTHR_ALL. * gmon.c (_mcleanup): Add support for multiple simultaneous gmon.out* files named via environment variable GMON_OUT_PREFIX. * gmon.h (struct gmonparam): Make state decl volatile. * mcount.c (_MCOUNT_DECL): Change stores into gmonparam.state to use Interlocked operations. Add #include "winsup.h", update commentary. * profil.c (profthr_byhandle): New function abstracting out the updating of profile counters based on a thread handle. (profthr_func): Update to call profthr_byhandle() to sample the main thread then call cygheap_profthr_all() indirectly through cygwin_internal(CW_CYGHEAP_PROFTHR_ALL) to sample all other threads. (profile_off): Zero targthr to indicate profiling was turned off. (profile_on): Fix handle leak on failure path. (profile_child): New callback func to restart profiling in child process after a fork if the parent was being profiled. (profile_ctl): Call pthread_atfork() to set profile_child callback. Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2016-02-20 07:58:31 +01:00
if (InterlockedCompareExchange (
&p->state, GMON_PROF_BUSY, GMON_PROF_ON) != GMON_PROF_ON)
2000-02-17 20:38:33 +01:00
return;
/*
* check that frompcindex is a reasonable pc value.
* for example: signal catchers get called from the stack,
* not from text space. too bad.
*/
frompc -= p->lowpc;
if (frompc > p->textsize)
goto done;
#if (HASHFRACTION & (HASHFRACTION - 1)) == 0
if (p->hashfraction == HASHFRACTION)
frompcindex =
&p->froms[frompc / (HASHFRACTION * sizeof(*p->froms))];
else
#endif
frompcindex =
&p->froms[frompc / (p->hashfraction * sizeof(*p->froms))];
toindex = *frompcindex;
if (toindex == 0) {
/*
* first time traversing this arc
*/
toindex = ++p->tos[0].link;
if (toindex >= p->tolimit)
/* halt further profiling */
goto overflow;
*frompcindex = toindex;
top = &p->tos[toindex];
top->selfpc = selfpc;
top->count = 1;
top->link = 0;
goto done;
}
top = &p->tos[toindex];
if (top->selfpc == selfpc) {
/*
* arc at front of chain; usual case.
*/
top->count++;
goto done;
}
/*
* have to go looking down chain for it.
* top points to what we are looking at,
* prevtop points to previous top.
* we know it is not at the head of the chain.
*/
for (; /* goto done */; ) {
if (top->link == 0) {
/*
* top is end of the chain and none of the chain
* had top->selfpc == selfpc.
* so we allocate a new tostruct
* and link it to the head of the chain.
*/
toindex = ++p->tos[0].link;
if (toindex >= p->tolimit)
goto overflow;
top = &p->tos[toindex];
top->selfpc = selfpc;
top->count = 1;
top->link = *frompcindex;
*frompcindex = toindex;
goto done;
}
/*
* otherwise, check the next arc on the chain.
*/
prevtop = top;
top = &p->tos[top->link];
if (top->selfpc == selfpc) {
/*
* there it is.
* increment its count
* move it to the head of the chain.
*/
top->count++;
toindex = prevtop->link;
prevtop->link = top->link;
top->link = *frompcindex;
*frompcindex = toindex;
goto done;
}
}
done:
Support profiling of multi-threaded apps. This patch set modifies Cygwin's profiling support to sample PC values of all an app's threads, not just the main thread. There is no change to how profiling is requested: just compile and link the app with "-pg" as usual. The profiling info is dumped into file gmon.out as always. A new facility enabled via the environment variable GMON_OUT_PREFIX. This facility is intended to match an undocumented Linux glibc feature. Exporting the variable with a non-empty value such as "foo" causes the profiling info to go to a file named foo.$pid instead of the default. With that, both resulting processes of a fork() can have their profiling data captured in separate files. gprof already knows how to accumulate data from multiple files if they all pertain to the same app. There is no change to the normal Cygwin execution paths if profiling is not enabled. And when it is enabled, only the one profiling thread per profiled app is doing more work than it used to. * include/sys/cygwin.h: Add CW_CYGHEAP_PROFTHR_ALL. * cygheap.cc (cygheap_profthr_all): New C-callable function that runs cygheap's threadlist handing each pthread's thread handle in turn to profthr_byhandle(). * external.cc (cygwin_internal): Add case CW_CYGHEAP_PROFTHR_ALL. * gmon.c (_mcleanup): Add support for multiple simultaneous gmon.out* files named via environment variable GMON_OUT_PREFIX. * gmon.h (struct gmonparam): Make state decl volatile. * mcount.c (_MCOUNT_DECL): Change stores into gmonparam.state to use Interlocked operations. Add #include "winsup.h", update commentary. * profil.c (profthr_byhandle): New function abstracting out the updating of profile counters based on a thread handle. (profthr_func): Update to call profthr_byhandle() to sample the main thread then call cygheap_profthr_all() indirectly through cygwin_internal(CW_CYGHEAP_PROFTHR_ALL) to sample all other threads. (profile_off): Zero targthr to indicate profiling was turned off. (profile_on): Fix handle leak on failure path. (profile_child): New callback func to restart profiling in child process after a fork if the parent was being profiled. (profile_ctl): Call pthread_atfork() to set profile_child callback. Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2016-02-20 07:58:31 +01:00
InterlockedExchange (&p->state, GMON_PROF_ON);
2000-02-17 20:38:33 +01:00
return;
overflow:
Support profiling of multi-threaded apps. This patch set modifies Cygwin's profiling support to sample PC values of all an app's threads, not just the main thread. There is no change to how profiling is requested: just compile and link the app with "-pg" as usual. The profiling info is dumped into file gmon.out as always. A new facility enabled via the environment variable GMON_OUT_PREFIX. This facility is intended to match an undocumented Linux glibc feature. Exporting the variable with a non-empty value such as "foo" causes the profiling info to go to a file named foo.$pid instead of the default. With that, both resulting processes of a fork() can have their profiling data captured in separate files. gprof already knows how to accumulate data from multiple files if they all pertain to the same app. There is no change to the normal Cygwin execution paths if profiling is not enabled. And when it is enabled, only the one profiling thread per profiled app is doing more work than it used to. * include/sys/cygwin.h: Add CW_CYGHEAP_PROFTHR_ALL. * cygheap.cc (cygheap_profthr_all): New C-callable function that runs cygheap's threadlist handing each pthread's thread handle in turn to profthr_byhandle(). * external.cc (cygwin_internal): Add case CW_CYGHEAP_PROFTHR_ALL. * gmon.c (_mcleanup): Add support for multiple simultaneous gmon.out* files named via environment variable GMON_OUT_PREFIX. * gmon.h (struct gmonparam): Make state decl volatile. * mcount.c (_MCOUNT_DECL): Change stores into gmonparam.state to use Interlocked operations. Add #include "winsup.h", update commentary. * profil.c (profthr_byhandle): New function abstracting out the updating of profile counters based on a thread handle. (profthr_func): Update to call profthr_byhandle() to sample the main thread then call cygheap_profthr_all() indirectly through cygwin_internal(CW_CYGHEAP_PROFTHR_ALL) to sample all other threads. (profile_off): Zero targthr to indicate profiling was turned off. (profile_on): Fix handle leak on failure path. (profile_child): New callback func to restart profiling in child process after a fork if the parent was being profiled. (profile_ctl): Call pthread_atfork() to set profile_child callback. Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
2016-02-20 07:58:31 +01:00
InterlockedExchange (&p->state, GMON_PROF_ERROR);
2000-02-17 20:38:33 +01:00
return;
}
/*
* Actual definition of mcount function. Defined in <machine/profile.h>,
* which is included by <sys/gmon.h>
*/
MCOUNT