+ nps->npcs_total_size += compressed;
+ nps->npcs_proc_count++;
+
+ }
+ return (0);
+}
+
+
+static int
+proc_pcontrol_null(__unused proc_t p, __unused void *arg)
+{
+ return(PROC_RETURNED);
+}
+
+
+/*
+ * Deal with the low on compressor pool space condition... this function
+ * gets called when we are approaching the limits of the compressor pool or
+ * we are unable to create a new swap file.
+ * Since this eventually creates a memory deadlock situtation, we need to take action to free up
+ * memory resources (both compressed and uncompressed) in order to prevent the system from hanging completely.
+ * There are 2 categories of processes to deal with. Those that have an action
+ * associated with them by the task itself and those that do not. Actionable
+ * tasks can have one of three categories specified: ones that
+ * can be killed immediately, ones that should be suspended, and ones that should
+ * be throttled. Processes that do not have an action associated with them are normally
+ * ignored unless they are utilizing such a large percentage of the compressor pool (currently 50%)
+ * that only by killing them can we hope to put the system back into a usable state.
+ */
+
+#define NO_PAGING_SPACE_DEBUG 0
+
+extern uint64_t vm_compressor_pages_compressed(void);
+
+struct timeval last_no_space_action = {0, 0};
+
+int
+no_paging_space_action()
+{
+ proc_t p;
+ struct no_paging_space nps;
+ struct timeval now;
+
+ /*
+ * Throttle how often we come through here. Once every 5 seconds should be plenty.
+ */
+ microtime(&now);
+
+ if (now.tv_sec <= last_no_space_action.tv_sec + 5)
+ return (0);
+
+ /*
+ * Examine all processes and find the biggest (biggest is based on the number of pages this
+ * task has in the compressor pool) that has been marked to have some action
+ * taken when swap space runs out... we also find the biggest that hasn't been marked for
+ * action.
+ *
+ * If the biggest non-actionable task is over the "dangerously big" threashold (currently 50% of
+ * the total number of pages held by the compressor, we go ahead and kill it since no other task
+ * can have any real effect on the situation. Otherwise, we go after the actionable process.
+ */
+ bzero(&nps, sizeof(nps));
+
+ proc_iterate(PROC_ALLPROCLIST, proc_pcontrol_null, (void *)NULL, proc_pcontrol_filter, (void *)&nps);
+
+#if NO_PAGING_SPACE_DEBUG
+ printf("low swap: npcs_proc_count = %d, npcs_total_size = %qd, npcs_max_size = %qd\n",
+ nps.npcs_proc_count, nps.npcs_total_size, nps.npcs_max_size);
+ printf("low swap: pcs_proc_count = %d, pcs_total_size = %qd, pcs_max_size = %qd\n",
+ nps.pcs_proc_count, nps.pcs_total_size, nps.pcs_max_size);
+ printf("low swap: apcs_proc_count = %d, apcs_total_size = %qd\n",
+ nps.apcs_proc_count, nps.apcs_total_size);
+#endif
+ if (nps.npcs_max_size > (vm_compressor_pages_compressed() * 50) / 100) {
+ /*
+ * for now we'll knock out any task that has more then 50% of the pages
+ * held by the compressor
+ */
+ if ((p = proc_find(nps.npcs_pid)) != PROC_NULL) {
+
+ if (nps.npcs_uniqueid == p->p_uniqueid) {
+ /*
+ * verify this is still the same process
+ * in case the proc exited and the pid got reused while
+ * we were finishing the proc_iterate and getting to this point
+ */
+ last_no_space_action = now;
+
+ printf("low swap: killing pid %d (%s)\n", p->p_pid, p->p_comm);
+ psignal(p, SIGKILL);
+
+ proc_rele(p);
+
+ return (0);
+ }
+
+ proc_rele(p);
+ }
+ }
+
+ if (nps.pcs_max_size > 0) {
+ if ((p = proc_find(nps.pcs_pid)) != PROC_NULL) {
+
+ if (nps.pcs_uniqueid == p->p_uniqueid) {
+ /*
+ * verify this is still the same process
+ * in case the proc exited and the pid got reused while
+ * we were finishing the proc_iterate and getting to this point
+ */
+ last_no_space_action = now;
+
+ proc_dopcontrol(p);
+
+ proc_rele(p);
+
+ return (1);
+ }
+
+ proc_rele(p);
+ }
+ }
+ last_no_space_action = now;
+
+ printf("low swap: unable to find any eligible processes to take action on\n");
+
+ return (0);
+}
+
+int
+proc_trace_log(__unused proc_t p, struct proc_trace_log_args *uap, __unused int *retval)
+{
+ int ret = 0;
+ proc_t target_proc = PROC_NULL;
+ pid_t target_pid = uap->pid;
+ uint64_t target_uniqueid = uap->uniqueid;
+ task_t target_task = NULL;
+
+ if (priv_check_cred(kauth_cred_get(), PRIV_PROC_TRACE_INSPECT, 0)) {
+ ret = EPERM;
+ goto out;
+ }
+ target_proc = proc_find(target_pid);
+ if (target_proc != PROC_NULL) {
+ if (target_uniqueid != proc_uniqueid(target_proc)) {
+ ret = ENOENT;
+ goto out;
+ }
+
+ target_task = proc_task(target_proc);
+ if (task_send_trace_memory(target_task, target_pid, target_uniqueid)) {
+ ret = EINVAL;
+ goto out;
+ }
+ } else
+ ret = ENOENT;
+
+out:
+ if (target_proc != PROC_NULL)
+ proc_rele(target_proc);
+ return (ret);
+}
+
+#if VM_SCAN_FOR_SHADOW_CHAIN
+extern int vm_map_shadow_max(vm_map_t map);
+int proc_shadow_max(void);
+int proc_shadow_max(void)
+{
+ int retval, max;
+ proc_t p;
+ task_t task;
+ vm_map_t map;
+
+ max = 0;
+ proc_list_lock();
+ for (p = allproc.lh_first; (p != 0); p = p->p_list.le_next) {
+ if (p->p_stat == SIDL)
+ continue;
+ task = p->task;
+ if (task == NULL) {
+ continue;
+ }
+ map = get_task_map(task);
+ if (map == NULL) {
+ continue;
+ }
+ retval = vm_map_shadow_max(map);
+ if (retval > max) {
+ max = retval;
+ }
+ }
+ proc_list_unlock();
+ return max;
+}
+#endif /* VM_SCAN_FOR_SHADOW_CHAIN */
+
+void proc_set_responsible_pid(proc_t target_proc, pid_t responsible_pid);
+void proc_set_responsible_pid(proc_t target_proc, pid_t responsible_pid)
+{
+ if (target_proc != NULL) {
+ target_proc->p_responsible_pid = responsible_pid;
+ }
+ return;
+}
+
+int
+proc_chrooted(proc_t p)
+{
+ int retval = 0;
+
+ if (p) {
+ proc_fdlock(p);
+ retval = (p->p_fd->fd_rdir != NULL) ? 1 : 0;
+ proc_fdunlock(p);
projects / apple / xnu.git / blobdiff