summaryrefslogtreecommitdiffstats
path: root/src/vppinfra/clib.h
diff options
context:
space:
mode:
authorSirshak Das <sirshak.das@arm.com>2018-10-03 22:53:51 +0000
committerDamjan Marion <dmarion@me.com>2018-10-19 07:10:47 +0000
commit2f6d7bb93c157b874efb79a2d1583a4c368bf89a (patch)
tree05dc2867c598cbb8d711f074b4b0eb62dd464f41 /src/vppinfra/clib.h
parentbf3443b0f852f5a4c551d12f926defbd047f2161 (diff)
vppinfra: add atomic macros for __sync builtins
This is first part of addition of atomic macros with only macros for __sync builtins. - Based on earlier patch by Damjan (https://gerrit.fd.io/r/#/c/10729/) Additionally - clib_atomic_release macro added and used in the absence of any memory barrier. - clib_atomic_bool_cmp_and_swap added Change-Id: Ie4e48c1e184a652018d1d0d87c4be80ddd180a3b Original-patch-by: Damjan Marion <damarion@cisco.com> Signed-off-by: Sirshak Das <sirshak.das@arm.com> Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com> Reviewed-by: Ola Liljedahl <ola.liljedahl@arm.com> Reviewed-by: Steve Capper <steve.capper@arm.com>
Diffstat (limited to 'src/vppinfra/clib.h')
-rw-r--r--src/vppinfra/clib.h1
1 files changed, 1 insertions, 0 deletions
diff --git a/src/vppinfra/clib.h b/src/vppinfra/clib.h
index a6f88245d79..95dadd9c09d 100644
--- a/src/vppinfra/clib.h
+++ b/src/vppinfra/clib.h
@@ -46,6 +46,7 @@
#endif
#include <vppinfra/types.h>
+#include <vppinfra/atomics.h>
/* Global DEBUG flag. Setting this to 1 or 0 turns off
ASSERT (see vppinfra/error.h) & other debugging code. */
#n193'>193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 
/*
 * Copyright (c) 2015 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <stdio.h>
#include <time.h>
#include <sys/types.h>
#include <signal.h>
#include <sys/stat.h>
#include <unistd.h>

#include <vppinfra/clib.h>
#include <vppinfra/vec.h>
#include <vppinfra/hash.h>
#include <svm/svmdb.h>
#include <vppinfra/format.h>
#include <vppinfra/error.h>
#include <vppinfra/time.h>
#include <vppinfra/macros.h>

int
restart_main_fn (unformat_input_t * i)
{
  int verbose = 0;
  int old_pid;
  int wait;
  u8 *chroot_path = 0;
  svmdb_client_t *svmdb_client;
  volatile pid_t *pidp;
  struct stat statb;
  ino_t old_inode;
  int sleeps;
  svmdb_map_args_t _ma, *ma = &_ma;

  struct timespec _req, *req = &_req;
  struct timespec _rem, *rem = &_rem;

  if (geteuid ())
    clib_error ("vpp_restart: must be root...");

  while (unformat_check_input (i) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat (i, "verbose") || unformat (i, "v"))
	verbose = 1;
      else if (unformat (i, "chroot %s", &chroot_path))
	;
      else
	{
	  clib_error ("unknown input `%U'", format_unformat_error, i);
	  return 1;
	}
    }

  /*
   * Step 1: look up the current VPP pid in the shared-memory database
   */
  clib_memset (ma, 0, sizeof (*ma));
  ma->root_path = (char *) chroot_path;

  svmdb_client = svmdb_map (ma);

  pidp = svmdb_local_get_variable_reference (svmdb_client,
					     SVMDB_NAMESPACE_VEC, "vpp_pid");
  if (pidp == 0)
    {
      clib_error ("'vpp_pid' svm variable not found, vpp has never run?");
      return 2;
    }

  /* Spin for up to 10 seconds for vpp to start */
  for (wait = 0; wait < 1000; wait++)
    {
      req->tv_sec = 0;
      req->tv_nsec = 10000 * 1000;	/* 10 ms */
      while (nanosleep (req, rem) < 0)
	*req = *rem;

      if (*pidp)
	goto found2;
    }

  clib_error ("VPP not runnning...");
  return 3;

found2:

  old_pid = *pidp;

  /*
   * Step 2: sanity check the pid we discovered
   */
  if (verbose)
    fformat (stdout, "Sanity check current vpp pid %d\n", old_pid);

  if (kill (old_pid, 0) < 0)
    {
      svmdb_unmap (svmdb_client);
      clib_error ("vpp current pid %d not running...", old_pid);
      return 2;
    }

  if (verbose)
    fformat (stdout, "Sanity check vpp pid %d OK\n", old_pid);

  /*
   * Step 3: figure out the current vpp <--> client shared-VM file
   * inode number
   */
  if (stat ("/dev/shm/vpe-api", &statb) < 0)
    {
      clib_unix_error ("stat fail");
      return 4;
    }

  old_inode = statb.st_ino;

  if (verbose)
    fformat (stdout, "Old inode %u\n", old_inode);

  /* Note: restart wipes out the shared VM database */
  svmdb_unmap (svmdb_client);

  /*
   * Step 4: send SIGTERM to vpp.
   * systemd et al. will restart vpp after wiping out the shared-VM
   * database and (crucially) the shared API messaging segment
   */

  if (kill (old_pid, SIGTERM) < 0)
    {
      clib_unix_error ("SIGTERM fail");
      return 3;
    }

  sleeps = 0;

  /*
   * Step 5: wait up to 15 seconds for a new incarnation of
   * the shared-VM API segment to appear.
   */
  for (wait = 0; wait < 150; wait++)
    {
      if ((stat ("/dev/shm/vpe-api", &statb) < 0)
	  || statb.st_ino == old_inode)
	{
	  req->tv_sec = 0;
	  req->tv_nsec = 100000 * 1000;	/* 100 ms */
	  while (nanosleep (req, rem) < 0)
	    *req = *rem;
	  sleeps++;
	}
      else
	goto new_inode;
    }

  clib_error ("Timeout waiting for new inode to appear...");
  return 5;

new_inode:
  if (verbose && sleeps > 0)
    fformat (stdout, "Inode sleeps %d\n", sleeps);

  if (verbose)
    fformat (stdout, "New inode %u\n", statb.st_ino);

  /*
   * Step 6: remap the SVM database
   */
  svmdb_client = svmdb_map (ma);

  pidp = svmdb_local_get_variable_reference (svmdb_client,
					     SVMDB_NAMESPACE_VEC, "vpp_pid");
  if (pidp == 0)
    {
      clib_error ("post_restart: 'vpp_pid' svm variable not found,"
		  "vpp did not restart?");
      return 2;
    }

  sleeps = 0;

  /*
   * Step 7: wait for vpp to publish its new PID
   */

  /* Spin for up to 15 seconds */
  for (wait = 0; wait < 150; wait++)
    {
      if (*pidp && (*pidp != old_pid))
	goto restarted;
      req->tv_sec = 0;
      req->tv_nsec = 100000 * 1000;	/* 100 ms */
      while (nanosleep (req, rem) < 0)
	*req = *rem;
      sleeps++;
    }

  clib_error ("Timeout waiting for vpp to publish pid after restart...");
  return 4;

restarted:

  /* Done... */

  if (verbose && sleeps)
    fformat (stdout, "pid sleeps %d\n", sleeps);

  if (verbose)
    fformat (stdout, "New PID %d... Restarted...\n", *pidp);

  svmdb_unmap (svmdb_client);
  return 0;
}

int
main (int argc, char **argv)
{
  unformat_input_t i;
  int ret;

  clib_mem_init (0, 64ULL << 20);

  unformat_init_command_line (&i, argv);
  ret = restart_main_fn (&i);
  unformat_free (&i);
  return ret;
}

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */