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-rw-r--r--sysdeps/posix/sprofil.c357
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+/* Copyright (C) 2001 Free Software Foundation, Inc.
+ Contributed by David Mosberger-Tang <davidm@hpl.hp.com>.
+
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include <assert.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/time.h>
+#include <sys/profil.h>
+
+#ifndef SIGPROF
+# include <sysdeps/generic/sprofil.c>
+#else
+
+#include <libc-internal.h>
+
+struct region
+ {
+ size_t offset;
+ size_t nsamples;
+ unsigned int scale;
+ union
+ {
+ void *vp;
+ unsigned short *us;
+ unsigned int *ui;
+ }
+ sample;
+ size_t start;
+ size_t end;
+ };
+
+struct prof_info
+ {
+ unsigned int num_regions;
+ struct region *region;
+ struct region *last, *overflow;
+ struct itimerval saved_timer;
+ struct sigaction saved_action;
+ };
+
+static unsigned int overflow_counter;
+
+static struct region default_overflow_region =
+ {
+ offset: 0,
+ nsamples: 1,
+ scale: 2,
+ sample: { &overflow_counter },
+ start: 0,
+ end: ~(size_t) 0
+ };
+
+static struct prof_info prof_info;
+
+static inline unsigned long int
+pc_to_index (size_t pc, size_t offset, unsigned int scale, int prof_uint)
+{
+ size_t i = (pc - offset) / (prof_uint ? sizeof (int) : sizeof (short));
+
+ if (sizeof (unsigned long long int) > sizeof (size_t))
+ return (unsigned long long int) i * scale / 65536;
+ else
+ return i / 65536 * scale + i % 65536 * scale / 65536;
+}
+
+static inline size_t
+index_to_pc (unsigned long int n, size_t offset, unsigned int scale,
+ int prof_uint)
+{
+ size_t pc, bin_size = (prof_uint ? sizeof (int) : sizeof (short));
+
+ if (sizeof (unsigned long long int) > sizeof (size_t))
+ pc = offset + (unsigned long long int) n * bin_size * 65536ull / scale;
+ else
+ pc = (offset + n * bin_size / scale * 65536
+ + n * bin_size % scale * 65536 / scale);
+
+ if (pc_to_index (pc, offset, scale, prof_uint) < n)
+ /* Adjust for rounding error. */
+ ++pc;
+
+ assert (pc_to_index (pc - 1, offset, scale, prof_uint) < n
+ && pc_to_index (pc, offset, scale, prof_uint) >= n);
+
+ return pc;
+}
+
+static inline void
+profil_count (void *pcp, int prof_uint)
+{
+ struct region *region, *r = prof_info.last;
+ size_t lo, hi, mid, pc = (unsigned long int) pcp;
+ unsigned long int i;
+
+ /* Fast path: pc is in same region as before. */
+ if (pc >= r->start && pc < r->end)
+ region = r;
+ else
+ {
+ /* Slow path: do a binary search for the right region. */
+ lo = 0; hi = prof_info.num_regions - 1;
+ while (lo <= hi)
+ {
+ mid = (lo + hi) / 2;
+
+ r = prof_info.region + mid;
+ if (pc >= r->start && pc < r->end)
+ {
+ prof_info.last = r;
+ region = r;
+ break;
+ }
+
+ if (pc < r->start)
+ hi = mid - 1;
+ else
+ lo = mid + 1;
+ }
+
+ /* No matching region: increment overflow count. There is no point
+ in updating the cache here, as it won't hit anyhow. */
+ region = prof_info.overflow;
+ }
+
+ i = pc_to_index (pc, region->offset, region->scale, prof_uint);
+ if (i < r->nsamples)
+ {
+ if (prof_uint)
+ {
+ if (r->sample.ui[i] < (unsigned int) ~0)
+ ++r->sample.ui[i];
+ }
+ else
+ {
+ if (r->sample.us[i] < (unsigned short) ~0)
+ ++r->sample.us[i];
+ }
+ }
+ else
+ {
+ if (prof_uint)
+ ++prof_info.overflow->sample.ui[0];
+ else
+ ++prof_info.overflow->sample.us[0];
+ }
+}
+
+static inline void
+profil_count_ushort (void *pcp)
+{
+ profil_count (pcp, 0);
+}
+
+static inline void
+profil_count_uint (void *pcp)
+{
+ profil_count (pcp, 1);
+}
+
+/* Get the machine-dependent definition of `profil_counter', the signal
+ handler for SIGPROF. It calls `profil_count' (above) with the PC of the
+ interrupted code. */
+#define profil_counter profil_counter_ushort
+#define profil_count(pc) profil_count (pc, 0)
+#include "profil-counter.h"
+
+#undef profil_counter
+#undef profil_count
+
+#define profil_counter profil_counter_uint
+#define profil_count(pc) profil_count (pc, 1)
+#include "profil-counter.h"
+
+static int
+insert (int i, unsigned long int start, unsigned long int end, struct prof *p,
+ int prof_uint)
+{
+ struct region *r;
+ size_t to_copy;
+
+ if (start >= end)
+ return 0; /* don't bother with empty regions */
+
+ if (prof_info.num_regions == 0)
+ r = malloc (sizeof (*r));
+ else
+ r = realloc (prof_info.region, (prof_info.num_regions + 1) * sizeof (*r));
+ if (r == NULL)
+ return -1;
+
+ to_copy = prof_info.num_regions - i;
+ if (to_copy > 0)
+ memmove (r + i + 1, r + i, to_copy * sizeof (*r));
+
+ r[i].offset = p->pr_off;
+ r[i].nsamples = p->pr_size / (prof_uint ? sizeof (int) : sizeof (short));
+ r[i].scale = p->pr_scale;
+ r[i].sample.vp = p->pr_base;
+ r[i].start = start;
+ r[i].end = end;
+
+ prof_info.region = r;
+ ++prof_info.num_regions;
+
+ if (p->pr_off == 0 && p->pr_scale == 2)
+ prof_info.overflow = r;
+
+ return 0;
+}
+
+/* Add a new profiling region. If the new region overlaps with
+ existing ones, this may add multiple subregions so that the final
+ data structure is free of overlaps. The absence of overlaps makes
+ it possible to use a binary search in profil_count(). Note that
+ this function depends on new regions being presented in DECREASING
+ ORDER of starting address. */
+
+static int
+add_region (struct prof *p, int prof_uint)
+{
+ unsigned long int nsamples;
+ size_t start, end;
+ int i;
+
+ if (p->pr_scale < 2)
+ return 0;
+
+ nsamples = p->pr_size / (prof_uint ? sizeof (int) : sizeof (short));
+
+ start = p->pr_off;
+ end = index_to_pc (nsamples, p->pr_off, p->pr_scale, prof_uint);
+
+ /* Merge with existing regions. */
+ for (i = 0; i < prof_info.num_regions; ++i)
+ {
+ if (start < prof_info.region[i].start)
+ {
+ if (end < prof_info.region[i].start)
+ break;
+ else if (insert (i, start, prof_info.region[i].start, p, prof_uint)
+ < 0)
+ return -1;
+ }
+ start = prof_info.region[i].end;
+ }
+ return insert (i, start, end, p, prof_uint);
+}
+
+static int
+pcmp (const void *left, const void *right)
+{
+ struct prof *l = *(struct prof **) left;
+ struct prof *r = *(struct prof **) right;
+
+ if (l->pr_off < r->pr_off)
+ return 1;
+ else if (l->pr_off > r->pr_off)
+ return -1;
+ return 0;
+}
+
+int
+__sprofil (struct prof *profp, int profcnt, struct timeval *tvp,
+ unsigned int flags)
+{
+ struct prof *p[profcnt];
+ struct itimerval timer;
+ struct sigaction act;
+ int i;
+
+ if (tvp != NULL)
+ {
+ /* Return profiling period. */
+ unsigned long int t = 1000000 / __profile_frequency ();
+ tvp->tv_sec = t / 1000000;
+ tvp->tv_usec = t % 1000000;
+ }
+
+ if (prof_info.num_regions > 0)
+ {
+ /* Disable profiling. */
+ if (__setitimer (ITIMER_PROF, &prof_info.saved_timer, NULL) < 0)
+ return -1;
+
+ if (__sigaction (SIGPROF, &prof_info.saved_action, NULL) < 0)
+ return -1;
+
+ free (prof_info.region);
+ return 0;
+ }
+
+ prof_info.num_regions = 0;
+ prof_info.region = NULL;
+ prof_info.overflow = &default_overflow_region;
+
+ for (i = 0; i < profcnt; ++i)
+ p[i] = profp + i;
+
+ /* Sort in order of decreasing starting address: */
+ qsort (p, profcnt, sizeof (p[0]), pcmp);
+
+ /* Add regions in order of decreasing starting address: */
+ for (i = 0; i < profcnt; ++i)
+ if (add_region (p[i], (flags & PROF_UINT) != 0) < 0)
+ {
+ if (prof_info.region)
+ free (prof_info.region);
+ prof_info.num_regions = 0;
+ prof_info.region = NULL;
+ return -1;
+ }
+
+ if (prof_info.num_regions == 0)
+ return 0;
+
+ prof_info.last = prof_info.region;
+
+ /* Install SIGPROF handler. */
+ if (flags & PROF_UINT)
+ act.sa_handler = (sighandler_t) &profil_counter_uint;
+ else
+ act.sa_handler = (sighandler_t) &profil_counter_ushort;
+ act.sa_flags = SA_RESTART;
+ sigfillset (&act.sa_mask);
+ if (__sigaction (SIGPROF, &act, &prof_info.saved_action) < 0)
+ return -1;
+
+ /* Setup profiling timer. */
+ timer.it_value.tv_sec = 0;
+ timer.it_value.tv_usec = 1;
+ timer.it_interval = timer.it_value;
+ return __setitimer (ITIMER_PROF, &timer, &prof_info.saved_timer);
+}
+
+weak_alias (__sprofil, sprofil)
+
+#endif /* SIGPROF */
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