-----Original Message----- From: John Ferlan [mailto:jferlan@redhat.com] Sent: Thursday, October 11, 2018 4:58 AM To: Wang, Huaqiang <huaqiang.wang@intel.com>; libvir-list@redhat.com Cc: Feng, Shaohe <shaohe.feng@intel.com>; Niu, Bing <bing.niu@intel.com>; Ding, Jian-feng <jian-feng.ding@intel.com>; Zang, Rui <rui.zang@intel.com> Subject: Re: [libvirt] [PATCHv5 14/19] Util: Add function for checking if monitor is running
On 10/9/18 6:30 AM, Wang Huaqiang wrote:
Check monitor status by checking the PIDs are in file 'task' or not.
Signed-off-by: Wang Huaqiang <huaqiang.wang@intel.com> --- src/libvirt_private.syms | 1 + src/util/virresctrl.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++- src/util/virresctrl.h | 4 +++ 3 files changed, 88 insertions(+), 1 deletion(-)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 4b22ed4..c90e48a 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -2686,6 +2686,7 @@ virResctrlMonitorDeterminePath; virResctrlMonitorGetCacheLevel; virResctrlMonitorGetCacheOccupancy; virResctrlMonitorGetID; +virResctrlMonitorIsRunning; virResctrlMonitorNew; virResctrlMonitorRemove; virResctrlMonitorSetCacheLevel; diff --git a/src/util/virresctrl.c b/src/util/virresctrl.c index 41e8d48..67dfbb8 100644 --- a/src/util/virresctrl.c +++ b/src/util/virresctrl.c @@ -364,6 +364,9 @@ struct _virResctrlMonitor { char *path; /* Boolean flag for default monitor */ bool default_monitor; + /* Tracking the tasks' PID associated with this monitor */ + pid_t *pids; + size_t npids; /* The cache 'level', special for cache monitor */ unsigned int cache_level; }; @@ -425,6 +428,7 @@ virResctrlMonitorDispose(void *obj) virObjectUnref(monitor->alloc); VIR_FREE(monitor->id); VIR_FREE(monitor->path); + VIR_FREE(monitor->pids); }
@@ -2491,7 +2495,13 @@ int virResctrlMonitorAddPID(virResctrlMonitorPtr monitor, pid_t pid) { - return virResctrlAddPID(monitor->path, pid); + if (virResctrlAddPID(monitor->path, pid) < 0) + return -1; + + if (VIR_APPEND_ELEMENT(monitor->pids, monitor->npids, pid) < 0) + return -1; + + return 0; }
@@ -2762,3 +2772,75 @@ virResctrlMonitorSetDefault(virResctrlMonitorPtr monitor) { monitor->default_monitor = true; } + + +static int +virResctrlPIDCompare(const void *pida, const void *pidb) { + return *(pid_t*)pida - *(pid_t*)pidb; } + + +bool +virResctrlMonitorIsRunning(virResctrlMonitorPtr monitor) { + char *pidstr = NULL; + char **spids = NULL; + size_t nspids = 0; + pid_t *pids = NULL; + size_t npids = 0; + size_t i = 0; + int rv = -1; + bool ret = false; + + if (!monitor->path) + return false; + + if (monitor->npids == 0) + return false; + + rv = virFileReadValueString(&pidstr, "%s/tasks", monitor->path); + if (rv == -2) + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Task file '%s/tasks' does not exist"), + monitor->path); + if (rv < 0) + goto cleanup; + + /* no PID in task file */ + if (!*pidstr) + goto cleanup; + + spids = virStringSplitCount(pidstr, "\n", 0, &nspids); + if (nspids != monitor->npids) + return false;
This will cause a leak... "goto cleanup;"
My bad. Will be corrected.
+ + for (i = 0; i < nspids; i++) { + unsigned int val = 0; + pid_t pid = 0; + + if (virStrToLong_uip(spids[i], NULL, 0, &val) < 0) + goto cleanup; + + pid = (pid_t)val; + + if (VIR_APPEND_ELEMENT(pids, npids, pid) < 0) + goto cleanup; + } + + qsort(pids, npids, sizeof(pid_t), virResctrlPIDCompare); + qsort(monitor->pids, monitor->npids, sizeof(pid_t), + virResctrlPIDCompare); + + for (i = 0; i < monitor->npids; i++) { + if (monitor->pids[i] != pids[i]) + goto cleanup; + } + + ret = true; + cleanup:
NB: Any place where you get here without an error message, but w/ ret = false may cause "issues" for the caller especially since some of the ways to get here w/ @false do set an error message.
Got. Will add some comments for each return and each 'goto cleanup', and will refine the error message.
John
Thanks for review. Huaqiang
+ virStringListFree(spids); + VIR_FREE(pids); + VIR_FREE(pidstr); + + return ret; +} diff --git a/src/util/virresctrl.h b/src/util/virresctrl.h index 371df8a..c5794cb 100644 --- a/src/util/virresctrl.h +++ b/src/util/virresctrl.h @@ -230,4 +230,8 @@ virResctrlMonitorGetCacheOccupancy(virResctrlMonitorPtr monitor, unsigned int **bankcaches); void virResctrlMonitorSetDefault(virResctrlMonitorPtr monitor); + +bool +virResctrlMonitorIsRunning(virResctrlMonitorPtr monitor); + #endif /* __VIR_RESCTRL_H__ */