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authorUlrich Drepper <drepper@redhat.com>2002-11-26 22:50:54 +0000
committerUlrich Drepper <drepper@redhat.com>2002-11-26 22:50:54 +0000
commit76a50749f7af5935ba3739e815aa6a16ae4440d1 (patch)
treec16eac47f220f03fea74d80ef0a4e774809e94b7 /nptl/sockperf.c
parent6938e63f714b15c377d8cbf8e97b6f15b0e1b692 (diff)
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Initial revision cvs/initial
2002-11-26  Ulrich Drepper  <drepper@redhat.com>
	* allocatestack.c (queue_stack): Don't remove stack from list here.
	Do it in the caller.  Correct condition to prematurely terminate
	loop to free stacks.
	(__deallocate_stack): Remove stack from list here.
2002-11-26  Ulrich Drepper  <drepper@redhat.com>
	* Makefile (tests): Add tst-stack1.
	* tst-stack1.c: New file.
	* allocatestack.c (allocate_stack): Initialize the TCB on a user
	provided stack.
	* pthread_attr_getstack.c: Return bottom of the thread area.
2002-11-25  Ulrich Drepper  <drepper@redhat.com>
	* Makefile (libpthread-routines): Add pt-allocrtsig and
	pthread_kill_other_threads.
	* pt-allocrtsig.c: New file.
	* pthread_kill_other_threads.c: New file.
	* sysdeps/unix/sysv/linux/allocrtsig.c: Add additional aliases for
	all three functions.
	* sysdeps/unix/sysv/linux/Makefile (sysdep_routines): Remove
	allocrtsig.
	* sysdeps/unix/sysv/linux/Versions (libc:GLIBC_PRIVATE): Export
	__libc_current_sigrtmin_private, __libc_current_sigrtmax_private,
	and __libc_allocate_rtsig_private.
	* Versions (libpthread): Export pthread_kill_other_threads_np,
	__libc_current_sigrtmin, and __libc_current_sigrtmax.
2002-11-24  Ulrich Drepper  <drepper@redhat.com>

	* allocatestack.c (allocate_stack): stackaddr in attribute points to
	the end of the stack.  Adjust computations.
	When mprotect call fails dequeue stack and free it.
	* pthread_attr_setstack.c: Store top of the stack in stackaddr
	attribute.
	* pthread_getattr_np.c: Likewise.

	* descr.h (IS_DETACHED): Add some more parenthesis to prevent
	surprises.

2002-11-23  Ulrich Drepper  <drepper@redhat.com>

	* sysdeps/pthread/pthread.h (pthread_self): __THROW must come before
	attribute definitions.  Patch by Luca Barbieri <ldb@ldb.ods.org>.

2002-11-22  Ulrich Drepper  <drepper@redhat.com>

	* pthread_getspecific.c: Optimize access to first 2nd-level array.
	* pthread_setspecific.c: Likewise.

2002-11-21  Ulrich Drepper  <drepper@redhat.com>

	* sysdeps/unix/sysv/linux/i386/createthread.c: Remove CLONE_ flags
	definitions.  Get them from the official place.
	* sysdeps/unix/sysv/linux/i386/fork.c: Likewise.

	* sysdeps/unix/sysv/linux/i386/createthread.c: Update CLONE_* flags.
	Use new CLONE_ flags in clone() calls.

	* sysdeps/unix/sysv/linux/fork.c: Use ARCH_FORK to actually fork.
	* sysdeps/unix/sysv/linux/i386/fork.c: New file.

	* Versions: Add pthread_* functions for libc.
	* forward.c: New file.

	* sysdeps/pthread/Makefile (libpthread-sysdeps_routines): Add
	errno-loc.
	* herrno.c: New file.
	* res.c: New file.

	* Makefile (libpthread-routines): Remove sem_post, sem_wait,
	sem_trywait, and sem_timedwait.  Add herrno and res.
	* sem_init.c: Don't initialize lock and waiters members.
	* sem_open.c: Likewise.
	* sem_post.c: Removed.
	* sem_wait.c: Removed.
	* sem_trywait.c: Removed.
	* sem_timedwait.c: Removed.
	* sysdeps/unix/sysv/linux/i386/i486/lowlevelsem.S: Complete rewrite.
	Includes full implementations of sem_post, sem_wait, sem_trywait,
	and sem_timedwait.
	* sysdeps/unix/sysv/linux/i386/lowlevelsem.h (lll_sem_post): Adjust
	for new implementation.
	* sysdeps/unix/sysv/linux/internaltypes.h (struct sem): Remove lock
	and waiters fields.

	* tst-sem3.c: Improve error message.
	* tst-signal3.c: Likewise.

	* init.c (__pthread_initialize_minimal): Use set_tid_address syscall
	to tell the kernel about the termination futex and to initialize tid
	member.  Don't initialize main_thread.
	* descr.h (struct pthread): Remove main_thread member.
	* cancelllation.c (__do_cancel): Remove code handling main thread.
	The main thread is not special anymore.

	* allocatestack.c (__reclaim_stacks): Mark stacks as unused.  Add
	size of the stacks to stack_cache_actsize.

	* pt-readv.c: Add missing "defined".
	* pt-sigwait.c: Likewise.
	* pt-writev.c: Likewise.

2002-11-09  Ulrich Drepper  <drepper@redhat.com>

	* Versions: Export __connect from libpthread.
	Patch by Luca Barbieri <ldb@ldb.ods.org>.

	* Makefile (libpthread-routines): Add pt-raise.
	* sysdeps/unix/sysv/linux/raise.c: New file.
	* sysdeps/unix/sysv/linux/pt-raise.c: New file.
	* sysdeps/generic/pt-raise.c: New file.

	* pthread_cond_init.c: Initialize all data elements of the condvar
	structure.  Patch by Luca Barbieri <ldb@ldb.ods.org>.

	* pthread_attr_init.c: Actually implement 2.0 compatibility version.
	* pthread_create.c: Likewise.

	* Makefile (tests): Add tst-key1, tst-key2, tst-key3.
	* tst-key1.c: New file.
	* tst-key2.c: New file.
	* tst-key3.c: New file.

	* Versions: Export pthread_detach for version GLIBC_2.0.
	Reported by Saurabh Desai <sdesai@austin.ibm.com>.

2002-11-08  Ulrich Drepper  <drepper@redhat.com>

	* pthread_key_create.c: Terminate search after an unused key was found.
	Patch by Luca Barbieri <ldb@ldb.ods.org>.

	* sysdeps/unix/sysv/linux/i386/pthread_once.S: Return zero.
	Patch by Luca Barbieri <ldb@ldb.ods.org>.

2002-10-10  Ulrich Drepper  <drepper@redhat.com>

	* sysdeps/unix/sysv/linux/i386/i486/lowlevelsem.S: Use slow generic
	dynamic lookup for errno in PIC.

	* allocatestack.c (get_cached_stack): Rearrange code slightly to
	release the stack lock as soon as possible.
	Call _dl_allocate_tls_init for TCB from the cache to re-initialize
	the static TLS block.
	(allocate_stack): Call _dl_allocate_tls_init for user-provided stack.

	* cancellation.c: Renamed from cancelation.c.
	* Makefile: Adjust accordingly.
	* pthreadP.h (CANCELLATION_P): Renamed from CANCELATION_P.
	* cleanup_defer.c: Use CANCELLATION_P.
	* pthread_testcancel.c: Likewise.
	* descr.h: Fix spelling in comments.
	* init.c: Likewise.
	* pthread_getattr_np.c: Likewise.
	* pthread_getschedparam.c: Likewise.
	* pthread_setschedparam.c: Likewise.
	* Versions: Likewise.

	* pt-pselect.c: New file.
	* Makefile (libpthread-routines): Add pt-pselect.
	* Versions: Add pselect.

	* tst-cancel4.c: New file.
	* Makefile (tests): Add tst-cancel4.

2002-10-09  Ulrich Drepper  <drepper@redhat.com>

	* pthread_mutex_lock.c: Always record lock ownership.
	* pthread_mutex_timedlock.c: Likewise.
	* pthread_mutex_trylock.c: Likewise.

	* pt-readv.c: New file.
	* pt-writev.c: New file.
	* pt-creat.c: New file.
	* pt-msgrcv.c: New file.
	* pt-msgsnd.c: New file.
	* pt-poll.c: New file.
	* pt-select.c: New file.
	* pt-sigpause.c: New file.
	* pt-sigsuspend.c: New file.
	* pt-sigwait.c: New file.
	* pt-sigwaitinfo.c: New file.
	* pt-waitid.c: New file.
	* Makefile (libpthread-routines): Add pt-readv, pt-writev, pt-creat,
	pt-msgrcv, pt-msgsnd, pt-poll, pt-select, pt-sigpause, pt-sigsuspend,
	pt-sigwait, pt-sigwaitinfo, and pt-waitid.
	* Versions: Add all the new functions.

	* tst-exit1.c: New file.
	* Makefile (tests): Add tst-exit1.

	* sem_timedwait.c: Minor optimization for more optimal fastpath.

2002-10-08  Ulrich Drepper  <drepper@redhat.com>

	* pt-fcntl.c: Only enable asynchronous cancellation for F_SETLKW.

	* pthread_join.c: Enable asynchronous cancellation around lll_wait_tid
	call.  pthread_join is an official cancellation point.
	* pthread_timedjoin.c: Likewise.

	* pthread_cond_wait.c: Revert order in which internal lock are dropped
	and the condvar's mutex are retrieved.
	* pthread_cond_timedwait.c: Likewise.
	Reported by dice@saros.East.Sun.COM.

2002-10-07  Ulrich Drepper  <drepper@redhat.com>

	* pthreadP.h: Cut out all type definitions and move them...
	* sysdeps/unix/sysv/linux/internaltypes.h: ...here.  New file.
	* pthreadP.h: Include <internaltypes.h>.

	* sysdeps/unix/sysv/linux/i386/lowlevelsem.h (lll_sem_post): Little
	performance tweaks.

	* sem_trywait.c: Shuffle #includes around to get right order.
	* sem_timedwait.c: Likewise.
	* sem_post.c: Likewise.
	* sem_wait.c: Likewise.

	* nptl 0.3 released.

	* Makefile (tests): Add tst-signal3.
	* tst-signal3.c: New file.

2002-10-05  Ulrich Drepper  <drepper@redhat.com>

	* sysdeps/unix/sysv/linux/i386/lowlevelsem.h: Tell the compiler that
	the asms modify the sem object.
	(__lll_sem_timedwait): Now takes struct sem* as first parameter.

	* sysdeps/unix/sysv/linux/i386/bits/semaphore.h (sem_t): Don't expose
	the actual members.
	* pthreadP.h (struct sem): New type.  Actual semaphore type.
	* semaphoreP.h: Include pthreadP.h.
	* sem_getvalue.c: Adjust to sem_t change.
	* sem_init.c: Likewise.
	* sem_open.c: Likewise.
	* sem_post.c: Likewise.
	* sem_timedwait.c: Likewise.
	* sem_trywait.c: Likewise.
	* sem_wait.c: Likewise.

2002-10-04  Ulrich Drepper  <drepper@redhat.com>

	* Makefile (tests): Add tst-basic2, tst-exec1, tst-exec3, tst-exec3.
	* tst-basic2.c: New file.
	* tst-exec1.c: New file.
	* tst-exec2.c: New file.
	* tst-exec3.c: New file.

	* tst-fork1.c: Remove extra */.

	* nptl 0.2 released.  The API for IA-32 is complete.
Diffstat (limited to 'nptl/sockperf.c')
-rw-r--r--nptl/sockperf.c594
1 files changed, 594 insertions, 0 deletions
diff --git a/nptl/sockperf.c b/nptl/sockperf.c
new file mode 100644
index 0000000000..d29a6ee26a
--- /dev/null
+++ b/nptl/sockperf.c
@@ -0,0 +1,594 @@
+#define _GNU_SOURCE
+#include <argp.h>
+#include <complex.h>
+#include <errno.h>
+#include <error.h>
+#include <fcntl.h>
+#include <gd.h>
+#include <inttypes.h>
+#include <pthread.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/param.h>
+#include <sys/poll.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+
+#define size_x 320
+#define size_y 240
+
+
+#define PATH "/tmp/s.sockperf"
+
+
+struct thread_param
+{
+  unsigned int from;
+  unsigned int to;
+  unsigned int nserv;
+};
+
+struct coord
+{
+  unsigned int x;
+  unsigned int y;
+  complex double z;
+};
+
+
+/* We use 64bit values for the times.  */
+typedef unsigned long long int hp_timing_t;
+
+
+static unsigned int nclients = 2;
+static unsigned int nservers = 2;
+
+static bool timing;
+static int points;
+
+
+static complex double top_left = -0.7 + 0.2i;
+static complex double bottom_right = -0.5 - 0.0i;
+
+
+static int colors[256];
+static gdImagePtr image;
+static pthread_mutex_t image_lock;
+
+static int sock;
+
+
+static void *
+client (void *arg)
+{
+  struct thread_param *param = arg;
+  unsigned int cnt;
+  unsigned int nserv = param->nserv;
+  int clisock[nserv];
+  struct pollfd servpoll[nserv];
+  struct sockaddr_un servaddr;
+  socklen_t servlen;
+  struct coord c;
+
+  bool new_coord (void)
+    {
+      if (cnt >= param->to)
+	return false;
+
+      unsigned int row = cnt / size_x;
+      unsigned int col = cnt % size_x;
+
+      c.x = col;
+      c.y = row;
+      c.z = (top_left
+	     + ((col
+		 * (creal (bottom_right) - creal (top_left))) / size_x)
+	     + (_Complex_I * (row * (cimag (bottom_right) - cimag (top_left)))
+		/ size_y));
+
+      ++cnt;
+
+      return true;
+    }
+
+
+  for (cnt = 0; cnt < nserv; ++cnt)
+    {
+      servpoll[cnt].fd = socket (AF_UNIX, SOCK_STREAM, 0);
+      if (clisock < 0)
+	{
+	  puts ("cannot create socket in client");
+	  return NULL;
+	}
+
+      memset (&servaddr, '\0', sizeof (servaddr));
+      servaddr.sun_family = AF_UNIX;
+      strncpy (servaddr.sun_path, PATH, sizeof (servaddr.sun_path));
+      servlen = offsetof (struct sockaddr_un, sun_path) + strlen (PATH) + 1;
+
+
+      int err;
+      while (1)
+	{
+	  err = TEMP_FAILURE_RETRY (connect (servpoll[cnt].fd, &servaddr,
+					     servlen));
+	  if (err != -1 || errno != ECONNREFUSED)
+	    break;
+
+	  pthread_yield ();
+	}
+
+      if (err == -1)
+	{
+	  printf ("cannot connect: %m (%d)\n", errno);
+	  exit (1);
+	}
+
+      servpoll[cnt].events = POLLOUT;
+      servpoll[cnt].revents = 0;
+    }
+
+  cnt = param->from;
+
+  new_coord ();
+  bool z_valid = true;
+
+  while (1)
+    {
+      int i;
+      int n = poll (servpoll, nserv, -1);
+      if (n == -1)
+	{
+	  puts ("poll returned error");
+	  break;
+	}
+
+      bool cont = false;
+      for (i = 0; i < nserv && n > 0; ++i)
+	if (servpoll[i].revents != 0)
+	  {
+	    if (servpoll[i].revents == POLLIN)
+	      {
+		unsigned int vals[3];
+		if (TEMP_FAILURE_RETRY (read (servpoll[i].fd, &vals,
+					      sizeof (vals)))
+		    != sizeof (vals))
+		  {
+		    puts ("read error in client");
+		    return NULL;
+		  }
+
+		pthread_mutex_lock (&image_lock);
+
+		gdImageSetPixel (image, vals[0], vals[1], vals[2]);
+		++points;
+
+		pthread_mutex_unlock (&image_lock);
+
+		servpoll[i].events = POLLOUT;
+	      }
+	    else
+	      {
+		if (servpoll[i].revents != POLLOUT)
+		  printf ("revents: %hd != POLLOUT ???\n",
+			  servpoll[i].revents);
+
+		if (z_valid)
+		  {
+		    if (TEMP_FAILURE_RETRY (write (servpoll[i].fd, &c,
+						   sizeof (c))) != sizeof (c))
+		      {
+			puts ("write error in client");
+			return NULL;
+		      }
+		    cont = true;
+		    servpoll[i].events = POLLIN;
+
+		    z_valid = new_coord ();
+		    if (! z_valid)
+		      /* No more to do.  Clear the event fields.  */
+		      for (i = 0; i < nserv; ++i)
+			if (servpoll[i].events == POLLOUT)
+			  servpoll[i].events = servpoll[i].revents = 0;
+		  }
+		else
+		  servpoll[i].events = servpoll[i].revents = 0;
+	      }
+
+	    --n;
+	  }
+	else if (servpoll[i].events != 0)
+	  cont = true;
+
+      if (! cont && ! z_valid)
+	break;
+    }
+
+  c.x = 0xffffffff;
+  c.y = 0xffffffff;
+  for (cnt = 0; cnt < nserv; ++cnt)
+    {
+      TEMP_FAILURE_RETRY (write (servpoll[cnt].fd, &c, sizeof (c)));
+      close (servpoll[cnt].fd);
+    }
+
+  return NULL;
+}
+
+
+static void *
+server (void *arg)
+{
+  struct sockaddr_un cliaddr;
+  socklen_t clilen;
+  int clisock = TEMP_FAILURE_RETRY (accept (sock, &cliaddr, &clilen));
+
+  if (clisock == -1)
+    {
+      puts ("accept failed");
+      return NULL;
+    }
+
+  while (1)
+    {
+      struct coord c;
+
+      if (TEMP_FAILURE_RETRY (read (clisock, &c, sizeof (c))) != sizeof (c))
+	{
+	  printf ("server read failed: %m (%d)\n", errno);
+	  break;
+	}
+
+      if (c.x == 0xffffffff && c.y == 0xffffffff)
+	break;
+
+      unsigned int rnds = 0;
+      complex double z = c.z;
+      while (cabs (z) < 4.0)
+	{
+	  z = z * z - 1;
+	  if (++rnds == 255)
+	    break;
+	}
+
+      unsigned int vals[3] = { c.x, c.y, rnds };
+      if (TEMP_FAILURE_RETRY (write (clisock, vals, sizeof (vals)))
+	  != sizeof (vals))
+	{
+	  puts ("server write error");
+	  return NULL;
+	}
+    }
+
+  close (clisock);
+
+  return NULL;
+}
+
+
+static const char *outfilename = "test.png";
+
+
+static const struct argp_option options[] =
+  {
+    { "clients", 'c', "NUMBER", 0, "Number of client threads" },
+    { "servers", 's', "NUMBER", 0, "Number of server threads per client" },
+    { "timing", 'T', NULL, 0,
+      "Measure time from startup to the last thread finishing" },
+    { NULL, 0, NULL, 0, NULL }
+  };
+
+/* Prototype for option handler.  */
+static error_t parse_opt (int key, char *arg, struct argp_state *state);
+
+/* Data structure to communicate with argp functions.  */
+static struct argp argp =
+{
+  options, parse_opt
+};
+
+
+int
+main (int argc, char *argv[])
+{
+  int cnt;
+  FILE *outfile;
+  struct sockaddr_un servaddr;
+  socklen_t servlen;
+  int remaining;
+
+  /* Parse and process arguments.  */
+  argp_parse (&argp, argc, argv, 0, &remaining, NULL);
+
+
+  pthread_t servth[nservers * nclients];
+  pthread_t clntth[nclients];
+  struct thread_param clntparam[nclients];
+
+
+  image = gdImageCreate (size_x, size_y);
+  if (image == NULL)
+    {
+      puts ("gdImageCreate failed");
+      return 1;
+    }
+
+  for (cnt = 0; cnt < 255; ++cnt)
+    colors[cnt] = gdImageColorAllocate (image, 256 - cnt, 256 - cnt,
+					256 - cnt);
+  /* Black.  */
+  colors[cnt] = gdImageColorAllocate (image, 0, 0, 0);
+
+
+  sock = socket (AF_UNIX, SOCK_STREAM, 0);
+  if (sock < 0)
+    error (EXIT_FAILURE, errno, "cannot create socket");
+
+  memset (&servaddr, '\0', sizeof (servaddr));
+  servaddr.sun_family = AF_UNIX;
+  strncpy (servaddr.sun_path, PATH, sizeof (servaddr.sun_path));
+  servlen = offsetof (struct sockaddr_un, sun_path) + strlen (PATH) + 1;
+
+  if (bind (sock, &servaddr, servlen) == -1)
+    error (EXIT_FAILURE, errno, "bind failed");
+
+  listen (sock, SOMAXCONN);
+
+  pthread_mutex_init (&image_lock, NULL);
+
+
+  struct sigaction sa;
+  sa.sa_handler = SIG_IGN;
+  sigemptyset (&sa.sa_mask);
+  sa.sa_flags = 0;
+
+  clockid_t cl;
+  struct timespec start_time;
+  if (timing)
+    {
+      if (clock_getcpuclockid (0, &cl) != 0
+	  || clock_gettime (cl, &start_time) != 0)
+	timing = false;
+    }
+
+  /* Start the servers.  */
+  for (cnt = 0; cnt < nservers * nclients; ++cnt)
+    {
+      if (pthread_create (&servth[cnt], NULL, server, NULL) != 0)
+	{
+	  puts ("pthread_create for server failed");
+	  exit (1);
+	}
+    }
+
+  for (cnt = 0; cnt < nclients; ++cnt)
+    {
+      clntparam[cnt].from = cnt * (size_x * size_y) / nclients;
+      clntparam[cnt].to = MIN ((cnt + 1) * (size_x * size_y) / nclients,
+			       size_x * size_y);
+      clntparam[cnt].nserv = nservers;
+
+      if (pthread_create (&clntth[cnt], NULL, client, &clntparam[cnt]) != 0)
+	{
+	  puts ("pthread_create for client failed");
+	  exit (1);
+	}
+    }
+
+
+  /* Wait for the clients.  */
+  for (cnt = 0; cnt < nclients; ++cnt)
+    if (pthread_join (clntth[cnt], NULL) != 0)
+      {
+	puts ("client pthread_join failed");
+	exit (1);
+      }
+
+  /* Wait for the servers.  */
+  for (cnt = 0; cnt < nclients * nservers; ++cnt)
+    if (pthread_join (servth[cnt], NULL) != 0)
+      {
+	puts ("server pthread_join failed");
+	exit (1);
+      }
+
+
+  if (timing)
+    {
+      struct timespec end_time;
+
+      if (clock_gettime (cl, &end_time) == 0)
+	{
+	  end_time.tv_sec -= start_time.tv_sec;
+	  end_time.tv_nsec -= start_time.tv_nsec;
+	  if (end_time.tv_nsec < 0)
+	    {
+	      end_time.tv_nsec += 1000000000;
+	      --end_time.tv_sec;
+	    }
+
+	  printf ("\nRuntime: %lu.%09lu seconds\n%d points computed\n",
+		  (unsigned long int) end_time.tv_sec,
+		  (unsigned long int) end_time.tv_nsec,
+		  points);
+	}
+    }
+
+
+  outfile = fopen (outfilename, "w");
+  if (outfile == NULL)
+    error (EXIT_FAILURE, errno, "cannot open output file '%s'", outfilename);
+
+  gdImagePng (image, outfile);
+
+  fclose (outfile);
+
+  unlink (PATH);
+
+  return 0;
+}
+
+
+/* Handle program arguments.  */
+static error_t
+parse_opt (int key, char *arg, struct argp_state *state)
+{
+  switch (key)
+    {
+    case 'c':
+      nclients = strtoul (arg, NULL, 0);
+      break;
+
+    case 's':
+      nservers = strtoul (arg, NULL, 0);
+      break;
+
+    case 'T':
+      timing = true;
+      break;
+
+    default:
+      return ARGP_ERR_UNKNOWN;
+    }
+
+  return 0;
+}
+
+
+static hp_timing_t
+get_clockfreq (void)
+{
+  /* We read the information from the /proc filesystem.  It contains at
+     least one line like
+	cpu MHz         : 497.840237
+     or also
+	cpu MHz         : 497.841
+     We search for this line and convert the number in an integer.  */
+  static hp_timing_t result;
+  int fd;
+
+  /* If this function was called before, we know the result.  */
+  if (result != 0)
+    return result;
+
+  fd = open ("/proc/cpuinfo", O_RDONLY);
+  if (__builtin_expect (fd != -1, 1))
+    {
+      /* XXX AFAIK the /proc filesystem can generate "files" only up
+         to a size of 4096 bytes.  */
+      char buf[4096];
+      ssize_t n;
+
+      n = read (fd, buf, sizeof buf);
+      if (__builtin_expect (n, 1) > 0)
+	{
+	  char *mhz = memmem (buf, n, "cpu MHz", 7);
+
+	  if (__builtin_expect (mhz != NULL, 1))
+	    {
+	      char *endp = buf + n;
+	      int seen_decpoint = 0;
+	      int ndigits = 0;
+
+	      /* Search for the beginning of the string.  */
+	      while (mhz < endp && (*mhz < '0' || *mhz > '9') && *mhz != '\n')
+		++mhz;
+
+	      while (mhz < endp && *mhz != '\n')
+		{
+		  if (*mhz >= '0' && *mhz <= '9')
+		    {
+		      result *= 10;
+		      result += *mhz - '0';
+		      if (seen_decpoint)
+			++ndigits;
+		    }
+		  else if (*mhz == '.')
+		    seen_decpoint = 1;
+
+		  ++mhz;
+		}
+
+	      /* Compensate for missing digits at the end.  */
+	      while (ndigits++ < 6)
+		result *= 10;
+	    }
+	}
+
+      close (fd);
+    }
+
+  return result;
+}
+
+
+int
+clock_getcpuclockid (pid_t pid, clockid_t *clock_id)
+{
+  /* We don't allow any process ID but our own.  */
+  if (pid != 0 && pid != getpid ())
+    return EPERM;
+
+#ifdef CLOCK_PROCESS_CPUTIME_ID
+  /* Store the number.  */
+  *clock_id = CLOCK_PROCESS_CPUTIME_ID;
+
+  return 0;
+#else
+  /* We don't have a timer for that.  */
+  return ENOENT;
+#endif
+}
+
+
+#define HP_TIMING_NOW(Var)	__asm__ __volatile__ ("rdtsc" : "=A" (Var))
+
+/* Get current value of CLOCK and store it in TP.  */
+int
+clock_gettime (clockid_t clock_id, struct timespec *tp)
+{
+  int retval = -1;
+
+  switch (clock_id)
+    {
+    case CLOCK_PROCESS_CPUTIME_ID:
+      {
+
+	static hp_timing_t freq;
+	hp_timing_t tsc;
+
+	/* Get the current counter.  */
+	HP_TIMING_NOW (tsc);
+
+	if (freq == 0)
+	  {
+	    freq = get_clockfreq ();
+	    if (freq == 0)
+	      return EINVAL;
+	  }
+
+	/* Compute the seconds.  */
+	tp->tv_sec = tsc / freq;
+
+	/* And the nanoseconds.  This computation should be stable until
+	   we get machines with about 16GHz frequency.  */
+	tp->tv_nsec = ((tsc % freq) * UINT64_C (1000000000)) / freq;
+
+	retval = 0;
+      }
+    break;
+
+    default:
+      errno = EINVAL;
+      break;
+    }
+
+  return retval;
+}