diff options
Diffstat (limited to 'src/vat/restart.c')
| -rw-r--r-- | src/vat/restart.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/src/vat/restart.c b/src/vat/restart.c new file mode 100644 index 00000000..adeee000 --- /dev/null +++ b/src/vat/restart.c @@ -0,0 +1,246 @@ +/* + * 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 + */ + 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: + */ |