[PATCH v5 0/5] ch: handle events from cloud-hypervisor
changes from v4->v5: * Incase of invalid events, exit VirCHEventHandler * Open eventmonitor fifo (Reader end) in virCHMonitorNew itself. This way, we can clean exit incase open fails for some reason. changes from v3->v4: * Don't abort; instead kill the VM and exit * use g_clear_pointer along with g_free * Fix possible memory leak changes from v2->v3: * Remove patch 'utils: Implement virFileIsNamedPipe' as it is no more needed. * Remove the eventmonitorpath only if it exists * Added domain name as a prefix to logs from ch_events.c. This will make debugging easier. * Simplified event parsing logic by reserving a byte for null char. changes from v1->v2: * Rebase on latest master * Use /* */ for comments * Remove fifo file if already exists * Address other comments from Praveen Paladugu cloud-hypervisor raises various events, including VM lifecylce operations such as boot, shutdown, pause, resume, etc. Libvirt will now read these events and take the necessary actions, such as correctly updating the domain state. A FIFO file is passed to `--event-monitor` option of cloud-hypervisor. Libvirt creates a new thread that acts as the reader of the fifo file and continuously monitors for new events. Currently, shutdown events are handled by updating the domain state appropriately. Purna Pavan Chandra Aekkaladevi (5): ch: pass --event-monitor option to cloud-hypervisor ch: start a new thread for handling ch events ch: events: Read and parse cloud-hypervisor events ch: events: facilitate lifecycle events handling NEWS: Mention event handling support in ch driver NEWS.rst | 7 + po/POTFILES | 1 + src/ch/ch_events.c | 312 ++++++++++++++++++++++++++++++++++++++++++++ src/ch/ch_events.h | 54 ++++++++ src/ch/ch_monitor.c | 76 ++++++++++- src/ch/ch_monitor.h | 12 ++ src/ch/meson.build | 2 + 7 files changed, 458 insertions(+), 6 deletions(-) create mode 100644 src/ch/ch_events.c create mode 100644 src/ch/ch_events.h -- 2.34.1
The `--event-monitor` option in cloud-hypervisor outputs events to a specified file. This file can then be used to monitor VM lifecycle, other vmm events and trigger appropriate actions. Signed-off-by: Purna Pavan Chandra Aekkaladevi <paekkaladevi@linux.microsoft.com> Co-authored-by: Vineeth Pillai <viremana@linux.microsoft.com> --- src/ch/ch_monitor.c | 20 ++++++++++++++++---- src/ch/ch_monitor.h | 2 ++ 2 files changed, 18 insertions(+), 4 deletions(-) diff --git a/src/ch/ch_monitor.c b/src/ch/ch_monitor.c index d3f969e01a..a72ee40aa1 100644 --- a/src/ch/ch_monitor.c +++ b/src/ch/ch_monitor.c @@ -541,7 +541,6 @@ virCHMonitorNew(virDomainObj *vm, virCHDriverConfig *cfg, int logfile) { g_autoptr(virCHMonitor) mon = NULL; g_autoptr(virCommand) cmd = NULL; - const char *socketdir = cfg->stateDir; int socket_fd = 0; if (virCHMonitorInitialize() < 0) @@ -557,11 +556,13 @@ virCHMonitorNew(virDomainObj *vm, virCHDriverConfig *cfg, int logfile) } /* prepare to launch Cloud-Hypervisor socket */ - mon->socketpath = g_strdup_printf("%s/%s-socket", socketdir, vm->def->name); - if (g_mkdir_with_parents(socketdir, 0777) < 0) { + mon->socketpath = g_strdup_printf("%s/%s-socket", cfg->stateDir, vm->def->name); + mon->eventmonitorpath = g_strdup_printf("%s/%s-event-monitor", + cfg->stateDir, vm->def->name); + if (g_mkdir_with_parents(cfg->stateDir, 0777) < 0) { virReportSystemError(errno, _("Cannot create socket directory '%1$s'"), - socketdir); + cfg->stateDir); return NULL; } @@ -589,6 +590,9 @@ virCHMonitorNew(virDomainObj *vm, virCHDriverConfig *cfg, int logfile) virCommandAddArgFormat(cmd, "fd=%d", socket_fd); virCommandPassFD(cmd, socket_fd, VIR_COMMAND_PASS_FD_CLOSE_PARENT); + virCommandAddArg(cmd, "--event-monitor"); + virCommandAddArgFormat(cmd, "path=%s", mon->eventmonitorpath); + /* launch Cloud-Hypervisor socket */ if (virCommandRunAsync(cmd, &mon->pid) < 0) return NULL; @@ -634,6 +638,14 @@ void virCHMonitorClose(virCHMonitor *mon) g_clear_pointer(&mon->socketpath, g_free); } + if (mon->eventmonitorpath) { + if (virFileRemove(mon->eventmonitorpath, -1, -1) < 0) { + VIR_WARN("Unable to remove CH event monitor file '%s'", + mon->eventmonitorpath); + } + g_clear_pointer(&mon->eventmonitorpath, g_free); + } + virObjectUnref(mon); } diff --git a/src/ch/ch_monitor.h b/src/ch/ch_monitor.h index ca23301723..67dc54f9f4 100644 --- a/src/ch/ch_monitor.h +++ b/src/ch/ch_monitor.h @@ -96,6 +96,8 @@ struct _virCHMonitor { char *socketpath; + char *eventmonitorpath; + pid_t pid; virDomainObj *vm; -- 2.34.1
Use a FIFO(named pipe) for --event-monitor option in CH. Introduce a new thread, `virCHEventHandlerLoop`, to continuously monitor and handle events from cloud-hypervisor. Signed-off-by: Purna Pavan Chandra Aekkaladevi <paekkaladevi@linux.microsoft.com> Co-authored-by: Vineeth Pillai <viremana@linux.microsoft.com> --- src/ch/ch_events.c | 78 +++++++++++++++++++++++++++++++++++++++++++++ src/ch/ch_events.h | 26 +++++++++++++++ src/ch/ch_monitor.c | 60 +++++++++++++++++++++++++++++++--- src/ch/ch_monitor.h | 4 +++ src/ch/meson.build | 2 ++ 5 files changed, 166 insertions(+), 4 deletions(-) create mode 100644 src/ch/ch_events.c create mode 100644 src/ch/ch_events.h diff --git a/src/ch/ch_events.c b/src/ch/ch_events.c new file mode 100644 index 0000000000..b6bbce2db0 --- /dev/null +++ b/src/ch/ch_events.c @@ -0,0 +1,78 @@ +/* + * Copyright Microsoft Corp. 2024 + * + * ch_events.c: Handle Cloud-Hypervisor events + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library. If not, see + * <http://www.gnu.org/licenses/>. + */ + +#include <config.h> + +#include <fcntl.h> + +#include "ch_domain.h" +#include "ch_events.h" +#include "ch_process.h" +#include "virfile.h" +#include "virlog.h" + +VIR_LOG_INIT("ch.ch_events"); + + +static void virCHEventHandlerLoop(void *data) +{ + virCHMonitor *mon = data; + virDomainObj *vm = NULL; + + /* Obtain a vm reference */ + vm = virObjectRef(mon->vm); + + VIR_DEBUG("%s: Event handler loop thread starting", vm->def->name); + + while (g_atomic_int_get(&mon->event_handler_stop) == 0) { + VIR_DEBUG("%s: Reading events from event monitor file", vm->def->name); + /* Read and process events here */ + } + + virObjectUnref(vm); + VIR_DEBUG("%s: Event handler loop thread exiting", vm->def->name); + return; +} + +int virCHStartEventHandler(virCHMonitor *mon) +{ + g_autofree char *name = NULL; + name = g_strdup_printf("ch-evt-%d", mon->pid); + + virObjectRef(mon); + if (virThreadCreateFull(&mon->event_handler_thread, + false, + virCHEventHandlerLoop, + name, + false, + mon) < 0) { + virObjectUnref(mon); + return -1; + } + virObjectUnref(mon); + + g_atomic_int_set(&mon->event_handler_stop, 0); + return 0; +} + +void virCHStopEventHandler(virCHMonitor *mon) +{ + g_atomic_int_set(&mon->event_handler_stop, 1); +} diff --git a/src/ch/ch_events.h b/src/ch/ch_events.h new file mode 100644 index 0000000000..4c8a48231d --- /dev/null +++ b/src/ch/ch_events.h @@ -0,0 +1,26 @@ +/* + * Copyright Microsoft Corp. 2024 + * + * ch_events.h: header file for handling Cloud-Hypervisor events + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library. If not, see + * <http://www.gnu.org/licenses/>. + */ + +#pragma once + +#include "ch_monitor.h" + +int virCHStartEventHandler(virCHMonitor *mon); +void virCHStopEventHandler(virCHMonitor *mon); diff --git a/src/ch/ch_monitor.c b/src/ch/ch_monitor.c index a72ee40aa1..bedcde2dde 100644 --- a/src/ch/ch_monitor.c +++ b/src/ch/ch_monitor.c @@ -20,12 +20,14 @@ #include <config.h> +#include <fcntl.h> #include <stdio.h> #include <unistd.h> #include <curl/curl.h> #include "datatypes.h" #include "ch_conf.h" +#include "ch_events.h" #include "ch_interface.h" #include "ch_monitor.h" #include "domain_interface.h" @@ -542,6 +544,7 @@ virCHMonitorNew(virDomainObj *vm, virCHDriverConfig *cfg, int logfile) g_autoptr(virCHMonitor) mon = NULL; g_autoptr(virCommand) cmd = NULL; int socket_fd = 0; + int event_monitor_fd; if (virCHMonitorInitialize() < 0) return NULL; @@ -549,6 +552,9 @@ virCHMonitorNew(virDomainObj *vm, virCHDriverConfig *cfg, int logfile) if (!(mon = virObjectLockableNew(virCHMonitorClass))) return NULL; + /* avoid VIR_FORCE_CLOSE()-ing garbage fd value in virCHMonitorClose */ + mon->eventmonitorfd = -1; + if (!vm->def) { virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("VM is not defined")); @@ -557,8 +563,6 @@ virCHMonitorNew(virDomainObj *vm, virCHDriverConfig *cfg, int logfile) /* prepare to launch Cloud-Hypervisor socket */ mon->socketpath = g_strdup_printf("%s/%s-socket", cfg->stateDir, vm->def->name); - mon->eventmonitorpath = g_strdup_printf("%s/%s-event-monitor", - cfg->stateDir, vm->def->name); if (g_mkdir_with_parents(cfg->stateDir, 0777) < 0) { virReportSystemError(errno, _("Cannot create socket directory '%1$s'"), @@ -573,6 +577,27 @@ virCHMonitorNew(virDomainObj *vm, virCHDriverConfig *cfg, int logfile) return NULL; } + /* Event monitor file to listen for VM state changes */ + mon->eventmonitorpath = g_strdup_printf("%s/%s-event-monitor-fifo", + cfg->stateDir, vm->def->name); + if (virFileExists(mon->eventmonitorpath)) { + VIR_WARN("Monitor file (%s) already exists, trying to delete!", + mon->eventmonitorpath); + if (virFileRemove(mon->eventmonitorpath, -1, -1) < 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Failed to remove the file: %1$s"), + mon->eventmonitorpath); + return NULL; + } + } + + if (mkfifo(mon->eventmonitorpath, S_IWUSR | S_IRUSR) < 0 && + errno != EEXIST) { + virReportSystemError(errno, "%s", + _("Cannot create monitor FIFO")); + return NULL; + } + cmd = virCommandNew(vm->def->emulator); virCommandSetOutputFD(cmd, &logfile); virCommandSetErrorFD(cmd, &logfile); @@ -597,12 +622,35 @@ virCHMonitorNew(virDomainObj *vm, virCHDriverConfig *cfg, int logfile) if (virCommandRunAsync(cmd, &mon->pid) < 0) return NULL; - /* get a curl handle */ - mon->handle = curl_easy_init(); + /* open the reader end of fifo before start Event Handler */ + while ((event_monitor_fd = open(mon->eventmonitorpath, O_RDONLY)) < 0) { + if (errno == EINTR) { + /* 100 milli seconds */ + g_usleep(100000); + continue; + } + /* Any other error should be a BUG(kernel/libc/libvirtd) + * (ENOMEM can happen on exceeding per-user limits) + */ + VIR_ERROR(_("%1$s: Failed to open the event monitor FIFO(%2$s) read end!"), + vm->def->name, mon->eventmonitorpath); + /* CH process(Writer) is blocked at this point as EventHandler(Reader) + * fails to open the FIFO. + */ + return NULL; + } + mon->eventmonitorfd = event_monitor_fd; + VIR_DEBUG("%s: Opened the event monitor FIFO(%s)", vm->def->name, mon->eventmonitorpath); /* now has its own reference */ mon->vm = virObjectRef(vm); + if (virCHStartEventHandler(mon) < 0) + return NULL; + + /* get a curl handle */ + mon->handle = curl_easy_init(); + return g_steal_pointer(&mon); } @@ -638,6 +686,10 @@ void virCHMonitorClose(virCHMonitor *mon) g_clear_pointer(&mon->socketpath, g_free); } + virCHStopEventHandler(mon); + if (mon->eventmonitorfd >= 0) { + VIR_FORCE_CLOSE(mon->eventmonitorfd); + } if (mon->eventmonitorpath) { if (virFileRemove(mon->eventmonitorpath, -1, -1) < 0) { VIR_WARN("Unable to remove CH event monitor file '%s'", diff --git a/src/ch/ch_monitor.h b/src/ch/ch_monitor.h index 67dc54f9f4..b9092f22b8 100644 --- a/src/ch/ch_monitor.h +++ b/src/ch/ch_monitor.h @@ -97,6 +97,10 @@ struct _virCHMonitor { char *socketpath; char *eventmonitorpath; + int eventmonitorfd; + + virThread event_handler_thread; + int event_handler_stop; pid_t pid; diff --git a/src/ch/meson.build b/src/ch/meson.build index ca1291c158..0b4a5aeb49 100644 --- a/src/ch/meson.build +++ b/src/ch/meson.build @@ -7,6 +7,8 @@ ch_driver_sources = [ 'ch_domain.h', 'ch_driver.c', 'ch_driver.h', + 'ch_events.c', + 'ch_events.h', 'ch_interface.c', 'ch_interface.h', 'ch_monitor.c', -- 2.34.1
Implement `chReadProcessEvents` and `chProcessEvents` to read events from event monitor FIFO file and parse them accordingly. Signed-off-by: Purna Pavan Chandra Aekkaladevi <paekkaladevi@linux.microsoft.com> Co-authored-by: Vineeth Pillai <viremana@linux.microsoft.com> --- po/POTFILES | 1 + src/ch/ch_events.c | 141 +++++++++++++++++++++++++++++++++++++++++++- src/ch/ch_events.h | 2 + src/ch/ch_monitor.h | 6 ++ 4 files changed, 147 insertions(+), 3 deletions(-) diff --git a/po/POTFILES b/po/POTFILES index 484b34c3df..d4b3de781b 100644 --- a/po/POTFILES +++ b/po/POTFILES @@ -22,6 +22,7 @@ src/bhyve/bhyve_process.c src/ch/ch_conf.c src/ch/ch_domain.c src/ch/ch_driver.c +src/ch/ch_events.c src/ch/ch_hostdev.c src/ch/ch_interface.c src/ch/ch_monitor.c diff --git a/src/ch/ch_events.c b/src/ch/ch_events.c index b6bbce2db0..c5c703ded7 100644 --- a/src/ch/ch_events.c +++ b/src/ch/ch_events.c @@ -20,8 +20,6 @@ #include <config.h> -#include <fcntl.h> - #include "ch_domain.h" #include "ch_events.h" #include "ch_process.h" @@ -31,6 +29,137 @@ VIR_LOG_INIT("ch.ch_events"); +/** + * virCHProcessEvents: + * @mon: the CH monitor object + * + * Parse the events from the event buffer and process them + * Example event: + * { + * "timestamp": { + * "secs": 0, + * "nanos": 29228206 + * }, + * "source": "vm", + * "event": "booted", + * "properties": null + * } + * + * Returns: 0 on success, -1 on failure + */ +static int virCHProcessEvents(virCHMonitor *mon) +{ + virDomainObj *vm = mon->vm; + char *buf = mon->event_buffer.buffer; + ssize_t sz = mon->event_buffer.buf_fill_sz; + virJSONValue *obj = NULL; + int blocks = 0; + size_t i = 0; + char *json_start; + ssize_t start_index = -1; + ssize_t end_index = -1; + char tmp; + + while (i < sz) { + if (buf[i] == '{') { + blocks++; + if (blocks == 1) + start_index = i; + } else if (buf[i] == '}' && blocks > 0) { + blocks--; + if (blocks == 0) { + /* valid json document */ + end_index = i; + + /* temporarily null terminate the JSON doc */ + tmp = buf[end_index + 1]; + buf[end_index + 1] = '\0'; + json_start = buf + start_index; + + if ((obj = virJSONValueFromString(json_start))) { + /* Process the event string (obj) here */ + virJSONValueFree(obj); + } else { + VIR_ERROR(_("%1$s: Invalid JSON event doc: %2$s"), + vm->def->name, json_start); + return -1; + } + + /* replace the original character */ + buf[end_index + 1] = tmp; + start_index = -1; + } + } + + i++; + } + + if (start_index == -1) { + /* We have processed all the JSON docs in the buffer */ + mon->event_buffer.buf_fill_sz = 0; + } else if (start_index > 0) { + /* We have an incomplete JSON doc at the end of the buffer + * Move it to the start of the buffer + */ + mon->event_buffer.buf_fill_sz = sz - start_index; + memmove(buf, buf+start_index, mon->event_buffer.buf_fill_sz); + } + + return 0; +} + +static int virCHReadProcessEvents(virCHMonitor *mon) +{ + /* Event json string must always terminate with null char. + * So, reserve one byte for '\0' at the end. + */ + size_t max_sz = CH_EVENT_BUFFER_SZ - 1; + char *buf = mon->event_buffer.buffer; + virDomainObj *vm = mon->vm; + bool incomplete = false; + size_t sz = 0; + int event_monitor_fd = mon->eventmonitorfd; + + memset(buf, 0, max_sz); + do { + ssize_t ret; + + ret = read(event_monitor_fd, buf + sz, max_sz - sz); + if (ret == 0 || (ret < 0 && errno == EINTR)) { + g_usleep(G_USEC_PER_SEC); + continue; + } else if (ret < 0) { + /* We should never reach here. read(2) says possible errors + * are EINTR, EAGAIN, EBADF, EFAULT, EINVAL, EIO, EISDIR + * We handle EINTR gracefully. There is some serious issue + * if we encounter any of the other errors(either in our code + * or in the system). + */ + VIR_ERROR(_("%1$s: Failed to read ch events!: %2$s"), + vm->def->name, g_strerror(errno)); + return -1; + } + + sz += ret; + mon->event_buffer.buf_fill_sz = sz; + + if (virCHProcessEvents(mon) < 0) { + VIR_ERROR(_("%1$s: Failed to parse and process events"), + vm->def->name); + return -1; + } + + if (mon->event_buffer.buf_fill_sz != 0) + incomplete = true; + else + incomplete = false; + sz = mon->event_buffer.buf_fill_sz; + + } while (virDomainObjIsActive(vm) && (sz < max_sz) && incomplete); + + return 0; +} + static void virCHEventHandlerLoop(void *data) { virCHMonitor *mon = data; @@ -41,11 +170,17 @@ static void virCHEventHandlerLoop(void *data) VIR_DEBUG("%s: Event handler loop thread starting", vm->def->name); + mon->event_buffer.buffer = g_malloc_n(sizeof(char), CH_EVENT_BUFFER_SZ); + mon->event_buffer.buf_fill_sz = 0; + while (g_atomic_int_get(&mon->event_handler_stop) == 0) { VIR_DEBUG("%s: Reading events from event monitor file", vm->def->name); - /* Read and process events here */ + if (virCHReadProcessEvents(mon) < 0) { + virCHStopEventHandler(mon); + } } + g_clear_pointer(&mon->event_buffer.buffer, g_free); virObjectUnref(vm); VIR_DEBUG("%s: Event handler loop thread exiting", vm->def->name); return; diff --git a/src/ch/ch_events.h b/src/ch/ch_events.h index 4c8a48231d..2e9cdf03bb 100644 --- a/src/ch/ch_events.h +++ b/src/ch/ch_events.h @@ -22,5 +22,7 @@ #include "ch_monitor.h" +#define CH_EVENT_BUFFER_SZ PIPE_BUF + int virCHStartEventHandler(virCHMonitor *mon); void virCHStopEventHandler(virCHMonitor *mon); diff --git a/src/ch/ch_monitor.h b/src/ch/ch_monitor.h index b9092f22b8..185de0dbfd 100644 --- a/src/ch/ch_monitor.h +++ b/src/ch/ch_monitor.h @@ -101,6 +101,12 @@ struct _virCHMonitor { virThread event_handler_thread; int event_handler_stop; + struct { + /* Buffer to hold the data read from pipe */ + char *buffer; + /* Size of the data read from pipe into buffer */ + size_t buf_fill_sz; + } event_buffer; pid_t pid; -- 2.34.1
On 1/17/25 18:11, Purna Pavan Chandra Aekkaladevi wrote:
Implement `chReadProcessEvents` and `chProcessEvents` to read events from event monitor FIFO file and parse them accordingly.
Signed-off-by: Purna Pavan Chandra Aekkaladevi <paekkaladevi@linux.microsoft.com> Co-authored-by: Vineeth Pillai <viremana@linux.microsoft.com> --- po/POTFILES | 1 + src/ch/ch_events.c | 141 +++++++++++++++++++++++++++++++++++++++++++- src/ch/ch_events.h | 2 + src/ch/ch_monitor.h | 6 ++ 4 files changed, 147 insertions(+), 3 deletions(-)
diff --git a/po/POTFILES b/po/POTFILES index 484b34c3df..d4b3de781b 100644 --- a/po/POTFILES +++ b/po/POTFILES @@ -22,6 +22,7 @@ src/bhyve/bhyve_process.c src/ch/ch_conf.c src/ch/ch_domain.c src/ch/ch_driver.c +src/ch/ch_events.c src/ch/ch_hostdev.c src/ch/ch_interface.c src/ch/ch_monitor.c diff --git a/src/ch/ch_events.c b/src/ch/ch_events.c index b6bbce2db0..c5c703ded7 100644 --- a/src/ch/ch_events.c +++ b/src/ch/ch_events.c @@ -20,8 +20,6 @@
#include <config.h>
-#include <fcntl.h> -
This include was added in the previous patch, only to be removed here :-)
#include "ch_domain.h" #include "ch_events.h" #include "ch_process.h" @@ -31,6 +29,137 @@ VIR_LOG_INIT("ch.ch_events");
+/** + * virCHProcessEvents: + * @mon: the CH monitor object + * + * Parse the events from the event buffer and process them + * Example event: + * { + * "timestamp": { + * "secs": 0, + * "nanos": 29228206 + * }, + * "source": "vm", + * "event": "booted", + * "properties": null + * } + * + * Returns: 0 on success, -1 on failure + */ +static int virCHProcessEvents(virCHMonitor *mon) +{ + virDomainObj *vm = mon->vm; + char *buf = mon->event_buffer.buffer; + ssize_t sz = mon->event_buffer.buf_fill_sz; + virJSONValue *obj = NULL; + int blocks = 0; + size_t i = 0; + char *json_start; + ssize_t start_index = -1; + ssize_t end_index = -1; + char tmp; + + while (i < sz) { + if (buf[i] == '{') { + blocks++; + if (blocks == 1) + start_index = i; + } else if (buf[i] == '}' && blocks > 0) { + blocks--; + if (blocks == 0) { + /* valid json document */ + end_index = i; + + /* temporarily null terminate the JSON doc */ + tmp = buf[end_index + 1]; + buf[end_index + 1] = '\0'; + json_start = buf + start_index; + + if ((obj = virJSONValueFromString(json_start))) { + /* Process the event string (obj) here */ + virJSONValueFree(obj); + } else { + VIR_ERROR(_("%1$s: Invalid JSON event doc: %2$s"), + vm->def->name, json_start); + return -1; + } + + /* replace the original character */ + buf[end_index + 1] = tmp; + start_index = -1; + } + } + + i++; + } + + if (start_index == -1) { + /* We have processed all the JSON docs in the buffer */ + mon->event_buffer.buf_fill_sz = 0; + } else if (start_index > 0) { + /* We have an incomplete JSON doc at the end of the buffer + * Move it to the start of the buffer + */ + mon->event_buffer.buf_fill_sz = sz - start_index; + memmove(buf, buf+start_index, mon->event_buffer.buf_fill_sz); + } + + return 0; +} + +static int virCHReadProcessEvents(virCHMonitor *mon) +{ + /* Event json string must always terminate with null char. + * So, reserve one byte for '\0' at the end. + */ + size_t max_sz = CH_EVENT_BUFFER_SZ - 1; + char *buf = mon->event_buffer.buffer; + virDomainObj *vm = mon->vm; + bool incomplete = false; + size_t sz = 0; + int event_monitor_fd = mon->eventmonitorfd; + + memset(buf, 0, max_sz); + do { + ssize_t ret; + + ret = read(event_monitor_fd, buf + sz, max_sz - sz); + if (ret == 0 || (ret < 0 && errno == EINTR)) { + g_usleep(G_USEC_PER_SEC); + continue; + } else if (ret < 0) { + /* We should never reach here. read(2) says possible errors + * are EINTR, EAGAIN, EBADF, EFAULT, EINVAL, EIO, EISDIR + * We handle EINTR gracefully. There is some serious issue + * if we encounter any of the other errors(either in our code + * or in the system). + */ + VIR_ERROR(_("%1$s: Failed to read ch events!: %2$s"), + vm->def->name, g_strerror(errno)); + return -1; + } + + sz += ret; + mon->event_buffer.buf_fill_sz = sz; + + if (virCHProcessEvents(mon) < 0) { + VIR_ERROR(_("%1$s: Failed to parse and process events"), + vm->def->name); + return -1; + } + + if (mon->event_buffer.buf_fill_sz != 0) + incomplete = true; + else + incomplete = false; + sz = mon->event_buffer.buf_fill_sz; + + } while (virDomainObjIsActive(vm) && (sz < max_sz) && incomplete); + + return 0; +} + static void virCHEventHandlerLoop(void *data) { virCHMonitor *mon = data; @@ -41,11 +170,17 @@ static void virCHEventHandlerLoop(void *data)
VIR_DEBUG("%s: Event handler loop thread starting", vm->def->name);
+ mon->event_buffer.buffer = g_malloc_n(sizeof(char), CH_EVENT_BUFFER_SZ);
Or g_new0(char, CH_EVENT_BUFFER_SZ); Michal
Implement `virCHProcessEvent` that maps event string to corresponding event type and take appropriate actions. As part of this, handle the shutdown event by correctly updating the domain state. This change also facilitates the handling of other VM lifecycle events, such as booting, rebooting, pause, resume, etc. Signed-off-by: Purna Pavan Chandra Aekkaladevi <paekkaladevi@linux.microsoft.com> --- src/ch/ch_events.c | 101 ++++++++++++++++++++++++++++++++++++++++++++- src/ch/ch_events.h | 26 ++++++++++++ 2 files changed, 126 insertions(+), 1 deletion(-) diff --git a/src/ch/ch_events.c b/src/ch/ch_events.c index c5c703ded7..685ddeaa31 100644 --- a/src/ch/ch_events.c +++ b/src/ch/ch_events.c @@ -28,6 +28,101 @@ VIR_LOG_INIT("ch.ch_events"); +VIR_ENUM_IMPL(virCHEvent, + VIR_CH_EVENT_LAST, + "vmm:starting", + "vmm:shutdown", + "vm:booting", + "vm:booted", + "vm:rebooting", + "vm:rebooted", + "vm:shutdown", + "vm:deleted", + "vm:pausing", + "vm:paused", + "vm:resuming", + "vm:resumed", + "vm:snapshotting", + "vm:snapshotted", + "vm:restoring", + "vm:restored", +); + +static int virCHEventStopProcess(virDomainObj *vm, + virDomainShutoffReason reason) +{ + virCHDriver *driver = ((virCHDomainObjPrivate *)vm->privateData)->driver; + + virObjectLock(vm); + if (virDomainObjBeginJob(vm, VIR_JOB_MODIFY)) + return -1; + virCHProcessStop(driver, vm, reason); + virDomainObjEndJob(vm); + virObjectUnlock(vm); + + return 0; +} + +static int virCHProcessEvent(virCHMonitor *mon, + virJSONValue *eventJSON) +{ + const char *event; + const char *source; + virCHEvent ev; + g_autofree char *timestamp = NULL; + g_autofree char *full_event = NULL; + virDomainObj *vm = mon->vm; + int ret = 0; + + if (virJSONValueObjectHasKey(eventJSON, "source") == 0) { + VIR_WARN("%s: Invalid JSON from monitor, no source key", vm->def->name); + return -1; + } + if (virJSONValueObjectHasKey(eventJSON, "event") == 0) { + VIR_WARN("%s: Invalid JSON from monitor, no event key", vm->def->name); + return -1; + } + source = virJSONValueObjectGetString(eventJSON, "source"); + event = virJSONValueObjectGetString(eventJSON, "event"); + full_event = g_strdup_printf("%s:%s", source, event); + ev = virCHEventTypeFromString(full_event); + VIR_DEBUG("%s: Source: %s, Event: %s, ev: %d", vm->def->name, source, event, ev); + + switch (ev) { + case VIR_CH_EVENT_VMM_STARTING: + case VIR_CH_EVENT_VM_BOOTING: + case VIR_CH_EVENT_VM_BOOTED: + case VIR_CH_EVENT_VM_REBOOTING: + case VIR_CH_EVENT_VM_REBOOTED: + case VIR_CH_EVENT_VM_PAUSING: + case VIR_CH_EVENT_VM_PAUSED: + case VIR_CH_EVENT_VM_RESUMING: + case VIR_CH_EVENT_VM_RESUMED: + case VIR_CH_EVENT_VM_SNAPSHOTTING: + case VIR_CH_EVENT_VM_SNAPSHOTTED: + case VIR_CH_EVENT_VM_RESTORING: + case VIR_CH_EVENT_VM_RESTORED: + case VIR_CH_EVENT_VM_DELETED: + break; + case VIR_CH_EVENT_VMM_SHUTDOWN: + if (virCHEventStopProcess(vm, VIR_DOMAIN_SHUTOFF_SHUTDOWN)) { + VIR_WARN("Failed to mark the VM(%s) as SHUTDOWN!", + vm->def->name); + ret = -1; + } + break; + case VIR_CH_EVENT_VM_SHUTDOWN: + virObjectLock(vm); + virDomainObjSetState(vm, VIR_DOMAIN_SHUTOFF, VIR_DOMAIN_SHUTOFF_SHUTDOWN); + virObjectUnlock(vm); + break; + case VIR_CH_EVENT_LAST: + default: + VIR_WARN("%s: Unknown event: %s", vm->def->name, full_event); + } + + return ret; +} /** * virCHProcessEvents: @@ -77,7 +172,11 @@ static int virCHProcessEvents(virCHMonitor *mon) json_start = buf + start_index; if ((obj = virJSONValueFromString(json_start))) { - /* Process the event string (obj) here */ + if (virCHProcessEvent(mon, obj) < 0) { + VIR_ERROR(_("%1$s: Failed to process JSON event doc: %2$s"), + vm->def->name, json_start); + return -1; + } virJSONValueFree(obj); } else { VIR_ERROR(_("%1$s: Invalid JSON event doc: %2$s"), diff --git a/src/ch/ch_events.h b/src/ch/ch_events.h index 2e9cdf03bb..3b360628f7 100644 --- a/src/ch/ch_events.h +++ b/src/ch/ch_events.h @@ -24,5 +24,31 @@ #define CH_EVENT_BUFFER_SZ PIPE_BUF +typedef enum { + /* source: vmm */ + VIR_CH_EVENT_VMM_STARTING = 0, + VIR_CH_EVENT_VMM_SHUTDOWN, + + /* source: vm */ + VIR_CH_EVENT_VM_BOOTING, + VIR_CH_EVENT_VM_BOOTED, + VIR_CH_EVENT_VM_REBOOTING, + VIR_CH_EVENT_VM_REBOOTED, + VIR_CH_EVENT_VM_SHUTDOWN, + VIR_CH_EVENT_VM_DELETED, + VIR_CH_EVENT_VM_PAUSING, + VIR_CH_EVENT_VM_PAUSED, + VIR_CH_EVENT_VM_RESUMING, + VIR_CH_EVENT_VM_RESUMED, + VIR_CH_EVENT_VM_SNAPSHOTTING, + VIR_CH_EVENT_VM_SNAPSHOTTED, + VIR_CH_EVENT_VM_RESTORING, + VIR_CH_EVENT_VM_RESTORED, + + VIR_CH_EVENT_LAST +} virCHEvent; + +VIR_ENUM_DECL(virCHEvent); + int virCHStartEventHandler(virCHMonitor *mon); void virCHStopEventHandler(virCHMonitor *mon); -- 2.34.1
Signed-off-by: Purna Pavan Chandra <paekkaladevi@linux.microsoft.com> Signed-off-by: Purna Pavan Chandra Aekkaladevi <paekkaladevi@linux.microsoft.com> --- NEWS.rst | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/NEWS.rst b/NEWS.rst index de8317be7b..c26dc3adb1 100644 --- a/NEWS.rst +++ b/NEWS.rst @@ -17,6 +17,13 @@ v11.1.0 (unreleased) * **New features** + * ch: Support handling events from cloud-hypervisor + + The ch driver now supports handling events from the cloud-hypervisor. + Events include VM lifecyle operations such as shutdown, pause, resume, + etc. Libvirt will now read these events and take actions such as + updating domain state, etc. + * **Improvements** * **Bug fixes** -- 2.34.1
LGTM! Praveen On 1/17/2025 11:11 AM, Purna Pavan Chandra Aekkaladevi wrote:
changes from v4->v5: * Incase of invalid events, exit VirCHEventHandler * Open eventmonitor fifo (Reader end) in virCHMonitorNew itself. This way, we can clean exit incase open fails for some reason.
changes from v3->v4: * Don't abort; instead kill the VM and exit * use g_clear_pointer along with g_free * Fix possible memory leak
changes from v2->v3: * Remove patch 'utils: Implement virFileIsNamedPipe' as it is no more needed. * Remove the eventmonitorpath only if it exists * Added domain name as a prefix to logs from ch_events.c. This will make debugging easier. * Simplified event parsing logic by reserving a byte for null char.
changes from v1->v2:
* Rebase on latest master * Use /* */ for comments * Remove fifo file if already exists * Address other comments from Praveen Paladugu
cloud-hypervisor raises various events, including VM lifecylce operations such as boot, shutdown, pause, resume, etc. Libvirt will now read these events and take the necessary actions, such as correctly updating the domain state. A FIFO file is passed to `--event-monitor` option of cloud-hypervisor. Libvirt creates a new thread that acts as the reader of the fifo file and continuously monitors for new events. Currently, shutdown events are handled by updating the domain state appropriately.
Purna Pavan Chandra Aekkaladevi (5): ch: pass --event-monitor option to cloud-hypervisor ch: start a new thread for handling ch events ch: events: Read and parse cloud-hypervisor events ch: events: facilitate lifecycle events handling NEWS: Mention event handling support in ch driver
NEWS.rst | 7 + po/POTFILES | 1 + src/ch/ch_events.c | 312 ++++++++++++++++++++++++++++++++++++++++++++ src/ch/ch_events.h | 54 ++++++++ src/ch/ch_monitor.c | 76 ++++++++++- src/ch/ch_monitor.h | 12 ++ src/ch/meson.build | 2 + 7 files changed, 458 insertions(+), 6 deletions(-) create mode 100644 src/ch/ch_events.c create mode 100644 src/ch/ch_events.h
-- Regards, Praveen K Paladugu
On 1/17/25 18:11, Purna Pavan Chandra Aekkaladevi wrote:
changes from v4->v5: * Incase of invalid events, exit VirCHEventHandler * Open eventmonitor fifo (Reader end) in virCHMonitorNew itself. This way, we can clean exit incase open fails for some reason.
changes from v3->v4: * Don't abort; instead kill the VM and exit * use g_clear_pointer along with g_free * Fix possible memory leak
changes from v2->v3: * Remove patch 'utils: Implement virFileIsNamedPipe' as it is no more needed. * Remove the eventmonitorpath only if it exists * Added domain name as a prefix to logs from ch_events.c. This will make debugging easier. * Simplified event parsing logic by reserving a byte for null char.
changes from v1->v2:
* Rebase on latest master * Use /* */ for comments * Remove fifo file if already exists * Address other comments from Praveen Paladugu
cloud-hypervisor raises various events, including VM lifecylce operations such as boot, shutdown, pause, resume, etc. Libvirt will now read these events and take the necessary actions, such as correctly updating the domain state. A FIFO file is passed to `--event-monitor` option of cloud-hypervisor. Libvirt creates a new thread that acts as the reader of the fifo file and continuously monitors for new events. Currently, shutdown events are handled by updating the domain state appropriately.
Purna Pavan Chandra Aekkaladevi (5): ch: pass --event-monitor option to cloud-hypervisor ch: start a new thread for handling ch events ch: events: Read and parse cloud-hypervisor events ch: events: facilitate lifecycle events handling NEWS: Mention event handling support in ch driver
NEWS.rst | 7 + po/POTFILES | 1 + src/ch/ch_events.c | 312 ++++++++++++++++++++++++++++++++++++++++++++ src/ch/ch_events.h | 54 ++++++++ src/ch/ch_monitor.c | 76 ++++++++++- src/ch/ch_monitor.h | 12 ++ src/ch/meson.build | 2 + 7 files changed, 458 insertions(+), 6 deletions(-) create mode 100644 src/ch/ch_events.c create mode 100644 src/ch/ch_events.h
Fixed small formatting issues and merged. Kudos for not forgetting NEWS.rst! Reviewed-by: Michal Privoznik <mprivozn@redhat.com> Michal
participants (3)
-
Michal Prívozník -
Praveen K Paladugu -
Purna Pavan Chandra Aekkaladevi