profile.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Routines to provide profiling of shared libraries required by the called
* executable.
*/
#include <stdio.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <synch.h>
#include <signal.h>
#include <synch.h>
#include <link.h>
#include <sys/param.h>
#include <procfs.h>
#include "msg.h"
#include "sgs.h"
#include "profile.h"
#include "_rtld.h"
static char Profile[MAXPATHLEN]; /* Profile buffer pathname */
static char *pname = 0; /* name of object to profile */
static L_hdr *Hptr; /* profile buffer header pointer */
static L_cgarc *Cptr; /* profile buffer call graph pointer */
static caddr_t Hpc, Lpc; /* Range of addresses being monitored */
static size_t Fsize; /* Size of mapped in profile buffer */
uintptr_t profcookie = 0;
/*
* When handling mutex's locally we need to mask signals. The signal
* mask is for everything except SIGWAITING.
*/
static const sigset_t iset = { ~0U, ~0U, ~0U, ~0U };
static lwp_mutex_t sharedmutex = SHAREDMUTEX;
static int
prof_mutex_init(lwp_mutex_t *mp)
{
(void) memcpy(mp, &sharedmutex, sizeof (lwp_mutex_t));
return (0);
}
static int
prof_mutex_lock(lwp_mutex_t *mp, sigset_t *oset)
{
if (oset)
(void) sigprocmask(SIG_BLOCK, &iset, oset);
(void) _lwp_mutex_lock(mp);
return (0);
}
static int
prof_mutex_unlock(mutex_t *mp, sigset_t *oset)
{
(void) _lwp_mutex_unlock(mp);
if (oset)
(void) sigprocmask(SIG_SETMASK, oset, NULL);
return (0);
}
extern char *_dgettext(const char *, const char *);
const char *
_ldprof_msg(Msg mid)
{
return (_dgettext(MSG_ORIG(MSG_SUNW_OST_SGS), MSG_ORIG(mid)));
}
/*
* Determine whether a set (of arbitrary size) is in use - used to analyze proc
* status information.
*/
static int
setisinuse(uint32_t *sp, uint_t n)
{
while (n--)
if (*sp++)
return (1);
return (0);
}
#define prisinuse(sp) \
setisinuse((uint32_t *)(sp), \
(uint_t)(sizeof (*(sp)) / sizeof (uint32_t)))
uint_t
la_version(uint_t version)
{
int fd;
ssize_t num;
pstatus_t status;
if (version < LAV_CURRENT) {
(void) fprintf(stderr, MSG_INTL(MSG_GEN_AUDITVERSION),
LAV_CURRENT, version);
return (LAV_CURRENT);
}
/*
* To reduce the potential for deadlock conditions that can arise from
* being monitored (say by truss(1)) while setting a lock in the profile
* buffer, determine if someone is monitoring us. If so silently
* disable profiling.
*/
if ((fd = open(MSG_ORIG(MSG_FMT_PROCSELF), O_RDONLY)) < 0)
return (LAV_CURRENT);
num = read(fd, &status, sizeof (status));
(void) close(fd);
if ((num != sizeof (status)) ||
prisinuse(&status.pr_sigtrace) || prisinuse(&status.pr_flttrace) ||
prisinuse(&status.pr_sysentry) || prisinuse(&status.pr_sysexit)) {
return (LAV_CURRENT);
}
/*
* We're presently not being monitored (although there's no control of
* someone attaching to us later), so retrieve the profile target name.
*/
if (dlinfo((void *)NULL, RTLD_DI_PROFILENAME, &pname) == -1)
(void) fprintf(stderr, MSG_INTL(MSG_GEN_PROFNOTSET));
return (LAV_CURRENT);
}
int
profile_open(const char *fname, Link_map *lmp)
{
size_t hsize; /* struct hdr size */
size_t psize; /* profile histogram size */
size_t csize; /* call graph array size */
size_t msize; /* size of memory being profiled */
int i, fd, fixed = 0;
caddr_t lpc;
caddr_t hpc;
caddr_t addr;
struct stat status;
int new_buffer = 0;
sigset_t mask;
int err;
Ehdr * ehdr; /* ELF header for file */
Phdr * phdr; /* program headers for file */
Dyn * dynp = 0; /* Dynamic section */
Word nsym = 0; /* no. of symtab ntries */
if (*Profile == '\0') {
const char *dir, *suf;
char *tmp;
/*
* From the basename of the specified filename generate the
* appropriate profile buffer name. The profile file is created
* if it does not already exist.
*/
if (((tmp = strrchr(fname, '/')) != 0) && (*(++tmp)))
fname = tmp;
#if defined(_ELF64)
suf = MSG_ORIG(MSG_SUF_PROFILE_64);
#else
suf = MSG_ORIG(MSG_SUF_PROFILE);
#endif
if (dlinfo((void *)NULL, RTLD_DI_PROFILEOUT, &dir) == -1)
dir = MSG_ORIG(MSG_PTH_VARTMP);
(void) snprintf(Profile, MAXPATHLEN, MSG_ORIG(MSG_FMT_PROFILE),
dir, fname, suf);
}
if ((fd = open(Profile, (O_RDWR | O_CREAT), 0666)) == -1) {
err = errno;
(void) fprintf(stderr, MSG_INTL(MSG_SYS_OPEN), Profile,
strerror(err));
return (0);
}
/*
* Now we determine the valid pc range for this object. The lpc is easy
* (lmp->l_addr), to determine the hpc we must examine the Phdrs.
*/
lpc = hpc = (caddr_t)lmp->l_addr;
/* LINTED */
ehdr = (Ehdr *)lpc;
if (ehdr->e_phnum == 0) {
(void) close(fd);
return (0);
}
if (ehdr->e_type == ET_EXEC)
fixed = 1;
/* LINTED */
phdr = (Phdr *)(ehdr->e_phoff + lpc);
for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
caddr_t _hpc;
if (phdr->p_type == PT_DYNAMIC) {
dynp = (Dyn *)phdr->p_vaddr;
if (fixed == 0) {
dynp = (Dyn *)((unsigned long)dynp +
(unsigned long)lpc);
}
continue;
}
if (phdr->p_type != PT_LOAD)
continue;
_hpc = (caddr_t)(phdr->p_vaddr + phdr->p_memsz);
if (fixed == 0) {
_hpc = (caddr_t)((unsigned long)_hpc +
(unsigned long)lpc);
}
if (_hpc > hpc)
hpc = _hpc;
}
if (lpc == hpc) {
(void) close(fd);
return (0);
}
/*
* In order to determine the number of symbols in the object scan the
* dynamic section until we find the DT_HASH entry (hash[1] == symcnt).
*/
if (dynp) {
for (; dynp->d_tag != DT_NULL; dynp++) {
unsigned int *hashp;
if (dynp->d_tag != DT_HASH)
continue;
hashp = (unsigned int *)dynp->d_un.d_ptr;
if (fixed == 0) {
hashp = (unsigned int *)((unsigned long)hashp +
(unsigned long)lpc);
}
nsym = hashp[1];
break;
}
}
/*
* Determine the (minimum) size of the buffer to allocate
*/
Lpc = lpc = (caddr_t)PRF_ROUNDWN((long)lpc, sizeof (long));
Hpc = hpc = (caddr_t)PRF_ROUNDUP((long)hpc, sizeof (long));
hsize = sizeof (L_hdr);
msize = (size_t)(hpc - lpc);
psize = (size_t)PRF_ROUNDUP((msize / PRF_BARSIZE), sizeof (long));
csize = (nsym + 1) * PRF_CGINIT * sizeof (L_cgarc);
Fsize = (hsize + psize + csize);
/*
* If the file size is zero (ie. we just created it), truncate it
* to the minimum size.
*/
(void) fstat(fd, &status);
if (status.st_size == 0) {
if (ftruncate(fd, Fsize) == -1) {
err = errno;
(void) fprintf(stderr, MSG_INTL(MSG_SYS_FTRUNC),
Profile, strerror(err));
(void) close(fd);
return (0);
}
new_buffer++;
} else
Fsize = status.st_size;
/*
* Map the file in.
*/
if ((addr = (caddr_t)mmap(0, Fsize, (PROT_READ | PROT_WRITE),
MAP_SHARED, fd, 0)) == (char *)-1) {
err = errno;
(void) fprintf(stderr, MSG_INTL(MSG_SYS_MMAP), Profile,
strerror(err));
(void) close(fd);
return (0);
}
(void) close(fd);
/*
* Initialize the remaining elements of the header. All pc addresses
* that are recorded are relative to zero thus allowing the recorded
* entries to be correlated with the symbols in the original file,
* and to compensate for any differences in where the file is mapped.
* If the high pc address has been initialized from a previous run,
* and the new entry is different from the original then a new library
* must have been installed. In this case bale out.
*/
/* LINTED */
Hptr = (L_hdr *)addr;
if (new_buffer)
(void) prof_mutex_init((lwp_mutex_t *)&Hptr->hd_mutex);
(void) prof_mutex_lock((mutex_t *)&Hptr->hd_mutex, &mask);
if (Hptr->hd_hpc) {
if (Hptr->hd_hpc != (caddr_t)(hpc - lpc)) {
(void) fprintf(stderr, MSG_INTL(MSG_GEN_PROFSZCHG),
Profile);
(void) prof_mutex_unlock((mutex_t *)&Hptr->
hd_mutex, &mask);
(void) munmap((caddr_t)Hptr, Fsize);
return (0);
}
} else {
/*
* Initialize the header information as we must have just
* created the output file.
*/
Hptr->hd_magic = (unsigned int)PRF_MAGIC;
#if defined(_ELF64)
Hptr->hd_version = (unsigned int)PRF_VERSION_64;
#else
Hptr->hd_version = (unsigned int)PRF_VERSION;
#endif
Hptr->hd_hpc = (caddr_t)(hpc - lpc);
/* LINTED */
Hptr->hd_psize = (unsigned int)psize;
/* LINTED */
Hptr->hd_fsize = (unsigned int)Fsize;
Hptr->hd_ncndx = nsym;
Hptr->hd_lcndx = (nsym + 1) * PRF_CGINIT;
}
(void) prof_mutex_unlock((mutex_t *)&Hptr->hd_mutex, &mask);
/* LINTED */
Cptr = (L_cgarc *)(addr + hsize + psize);
/*
* Turn on profiling
*/
/* LINTED */
profil((unsigned short *)(addr + hsize),
psize, (unsigned long)lpc, (unsigned int) PRF_SCALE);
return (1);
}
uint_t
/* ARGSUSED1 */
la_objopen(Link_map *lmp, Lmid_t lmid, uintptr_t *cookie)
{
char *objname;
/*
* This would only occur if the getenv() in la_version() failed.
* at this point there is nothing for us to do.
*/
if (pname == 0)
return (0);
/*
* Just grab the 'basename' of the object current object for
* comparing against the 'profiled object name'
*/
if (((objname = strrchr(lmp->l_name, '/')) == 0) ||
(*(++objname) == 0))
objname = lmp->l_name;
/*
* Is this the object we are going to profile. If not
* just set the 'BINDFROM' flag for this object.
*/
if ((strcmp(pname, objname) != 0) &&
(strcmp(pname, lmp->l_name) != 0))
return (LA_FLG_BINDFROM);
/*
* Don't even try to profile an object that does not have
* auditing enabled on it's link-map. This catches 'ld.so.1'.
*/
if (LIST((Rt_map *)lmp)->lm_flags & LML_FLG_NOAUDIT)
return (LA_FLG_BINDFROM);
if (profile_open(pname, lmp) == 0)
return (0);
profcookie = *cookie;
return (LA_FLG_BINDFROM | LA_FLG_BINDTO);
}
uint_t
la_objclose(uintptr_t *cookie)
{
if (*cookie != profcookie)
return (0);
profcookie = 0;
/*
* Turn profil() off.
*/
profil(0, 0, 0, 0);
(void) munmap((caddr_t)Hptr, Fsize);
return (0);
}
static int
remap_profile(int fd)
{
caddr_t addr;
size_t l_fsize;
l_fsize = Hptr->hd_fsize;
if ((addr = (caddr_t)mmap(0, l_fsize, (PROT_READ | PROT_WRITE),
MAP_SHARED, fd, 0)) == (char *)-1) {
int err = errno;
(void) fprintf(stderr, MSG_INTL(MSG_SYS_MMAP), Profile,
strerror(err));
return (0);
}
(void) munmap((caddr_t)Hptr, Fsize);
Fsize = l_fsize;
/* LINTED */
Hptr = (L_hdr*) addr;
/* LINTED */
Cptr = (L_cgarc *)(addr + sizeof (L_hdr) + Hptr->hd_psize);
return (1);
}
/*
* Update a call graph arc entry. This routine can be called three ways;
* o On initialization from one of the bndr() functions.
* In this case the `to' address is known, and may be used to
* initialize the call graph entry if this function has not
* been entered before.
* o On initial relocation (ie. LD_BIND_NOW). In this case the `to'
* address is known but the `from' isn't. The call graph entry
* is initialized to hold this dummy `to' address, but will be
* re-initialized later when a function is first called.
* o From an initialized plt entry. When profiling, the plt entries
* are filled in with the calling functions symbol index and
* the plt_cg_elf interface function. This interface function
* calls here to determine the `to' functions address, and in so
* doing increments the call count.
*/
uintptr_t
plt_cg_interp(uint_t ndx, caddr_t from, caddr_t to)
{
L_cgarc * cptr, cbucket;
sigset_t mask;
/*
* If the from address is outside of the address range being profiled,
* simply assign it to the `outside' address.
*/
if (from != PRF_UNKNOWN) {
if ((from > Hpc) || (from < Lpc))
from = PRF_OUTADDR;
else
from = (caddr_t)(from - Lpc);
}
(void) prof_mutex_lock((mutex_t *)&Hptr->hd_mutex, &mask);
/*
* Has the buffer grown since last we looked at it (another processes
* could have grown it...).
*/
/* LINTED */
if (Hptr->hd_fsize != (unsigned int)Fsize) {
int fd;
fd = open(Profile, O_RDWR, 0);
if (remap_profile(fd) == 0) {
(void) prof_mutex_unlock((mutex_t *)&Hptr->hd_mutex,
&mask);
exit(1);
}
(void) close(fd);
}
cptr = &Cptr[ndx];
if (cptr->cg_to == 0) {
/*
* If this is the first time this function has been called we
* got here from one of the binders or an initial relocation
* (ie. LD_BIND_NOW). In this case the `to' address is
* provided. Initialize this functions call graph entry with
* the functions address (retained as a relative offset).
* If we know where the function call originated from
* initialize the count field.
*/
cptr->cg_to = (caddr_t)(to - Lpc);
cptr->cg_from = from;
if (from != PRF_UNKNOWN)
cptr->cg_count = 1;
} else {
/*
* If a function has been called from a previous run, but we
* don't know where we came from (ie. LD_BIND_NOW), then later
* calls through the plt will be able to obtain the required
* functions address, thus there is no need to proceed further.
*/
if (from != PRF_UNKNOWN) {
/*
* If the from addresses match simply bump the count.
* If not scan the link list to find a match for this
* `from' address. If one doesn't exit create a new
* entry and link it in.
*/
while ((cptr->cg_from != from) &&
(cptr->cg_from != PRF_UNKNOWN)) {
if (cptr->cg_next != 0)
cptr = &Cptr[cptr->cg_next];
else {
to = cptr->cg_to;
cptr->cg_next = Hptr->hd_ncndx++;
cptr = &Cptr[cptr->cg_next];
/*
* If we've run out of file, extend it.
*/
if (Hptr->hd_ncndx == Hptr->hd_lcndx) {
caddr_t addr;
int fd;
/* LINTED */
Hptr->hd_fsize += (unsigned int)
PRF_CGNUMB *
sizeof (L_cgarc);
fd = open(Profile, O_RDWR, 0);
if (ftruncate(fd,
Hptr->hd_fsize) == -1) {
int err = errno;
(void) fprintf(stderr,
MSG_INTL(
MSG_SYS_FTRUNC),
Profile,
strerror(err));
(void) close(fd);
cptr = &cbucket;
}
/*
* Since the buffer will be
* remapped, we need to be
* prepared to adjust cptr.
*/
addr = (caddr_t)((Addr)cptr -
(Addr)Cptr);
if (remap_profile(fd) == 0) {
(void) prof_mutex_unlock(
(mutex_t *)&Hptr->
hd_mutex, &mask);
exit(1);
}
cptr = (L_cgarc *)((Addr)addr +
(Addr)Cptr);
(void) close(fd);
Hptr->hd_lcndx += PRF_CGNUMB;
}
cptr->cg_from = from;
cptr->cg_to = to;
}
}
/*
* If we're updating an entry from an unknown call
* address initialize this element, otherwise
* increment the call count.
*/
if (cptr->cg_from == PRF_UNKNOWN) {
cptr->cg_from = from;
cptr->cg_count = 1;
} else
cptr->cg_count++;
}
}
/*
* Return the real address of the function.
*/
(void) prof_mutex_unlock((mutex_t *)&Hptr->hd_mutex, &mask);
return ((uintptr_t)((Addr)cptr->cg_to + (Addr)Lpc));
}
/* ARGSUSED2 */
#if defined(__sparcv9)
uintptr_t
la_sparcv9_pltenter(Elf64_Sym *symp, uint_t symndx, uintptr_t *refcookie,
uintptr_t *defcookie, La_sparcv9_regs *regset, uint_t *sbflags,
const char *sym_name)
#elif defined(__sparc)
uintptr_t
la_sparcv8_pltenter(Elf32_Sym *symp, uint_t symndx, uintptr_t *refcookie,
uintptr_t *defcookie, La_sparcv8_regs *regset, uint_t *sbflags)
#elif defined(__amd64)
uintptr_t
la_amd64_pltenter(Elf64_Sym *symp, uint_t symndx, uintptr_t *refcookie,
uintptr_t *defcookie, La_amd64_regs *regset, uint_t *sbflags,
const char *sym_name)
#elif defined(__i386)
uintptr_t
la_i86_pltenter(Elf32_Sym *symp, uint_t symndx, uintptr_t *refcookie,
uintptr_t *defcookie, La_i86_regs *regset, uint_t *sbflags)
#else
#error unexpected architecture!
#endif
{
caddr_t from;
/*
* profiling has been disabled.
*/
if (profcookie == 0)
return (symp->st_value);
#if defined(__sparc) || defined(__sparcv9)
/*
* The callers return address is currently stored in O7 (which
* will become I7 when the window shift occurs).
*/
from = (caddr_t)regset->lr_rego7;
#elif defined(__amd64)
/*
* The callers return address is on the top of the stack for amd64
*/
from = *(caddr_t *)(regset->lr_rsp);
#elif defined(__i386)
/*
* The callers return address is on the top of the stack for i386
*/
from = *(caddr_t *)(regset->lr_esp);
#else
#error unexpected architecture!
#endif
return (plt_cg_interp(symndx, (caddr_t)from, (caddr_t)symp->st_value));
}