[libvirt] [PATCH v2 1/2] Add virProcessGetPids to get all tasks of a process

This function gets all the PIDs listed in /proc/PID/task. This will be needed at least to move all qmeu-nbd tasks to the container cgroup. --- src/libvirt_private.syms | 1 + src/util/virprocess.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ src/util/virprocess.h | 2 ++ 3 files changed, 50 insertions(+) diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 6a95fb9..780cfbb 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -1986,6 +1986,7 @@ virProcessAbort; virProcessExitWithStatus; virProcessGetAffinity; virProcessGetNamespaces; +virProcessGetPids; virProcessGetStartTime; virProcessKill; virProcessKillPainfully; diff --git a/src/util/virprocess.c b/src/util/virprocess.c index 7a79970..ce5e106 100644 --- a/src/util/virprocess.c +++ b/src/util/virprocess.c @@ -608,6 +608,53 @@ int virProcessGetAffinity(pid_t pid ATTRIBUTE_UNUSED, #endif /* HAVE_SCHED_GETAFFINITY */ +int virProcessGetPids(pid_t pid, size_t *npids, pid_t **pids) +{ + int ret = -1; + char *taskPath = NULL; + DIR *dir = NULL; + int value; + struct dirent *ent; + + *npids = 0; + *pids = NULL; + + if (virAsprintf(&taskPath, "/proc/%llu/task", + (unsigned long long)pid) < 0) + goto cleanup; + + if (!(dir = opendir(taskPath))) + goto cleanup; + + while ((value = virDirRead(dir, &ent, taskPath)) > 0) { + pid_t tmp_pid; + + /* Skip . and .. */ + if (STRPREFIX(ent->d_name, ".")) + continue; + + if (virStrToLong_i(ent->d_name, NULL, 10, &tmp_pid) < 0) + goto cleanup; + + if (VIR_APPEND_ELEMENT(*pids, *npids, tmp_pid) < 0) + goto cleanup; + } + + if (value < 0) + goto cleanup; + + ret = 0; + + cleanup: + if (!dir) + closedir(dir); + VIR_FREE(taskPath); + if (ret < 0) + VIR_FREE(*pids); + return ret; +} + + int virProcessGetNamespaces(pid_t pid, size_t *nfdlist, int **fdlist) diff --git a/src/util/virprocess.h b/src/util/virprocess.h index c812882..86a633d 100644 --- a/src/util/virprocess.h +++ b/src/util/virprocess.h @@ -62,6 +62,8 @@ int virProcessGetAffinity(pid_t pid, virBitmapPtr *map, int maxcpu); +int virProcessGetPids(pid_t pid, size_t *npids, pid_t **pids); + int virProcessGetStartTime(pid_t pid, unsigned long long *timestamp); -- 2.1.4