static DEFINE_PER_CPU(__u32, taskstats_seqnum) = { 0 };
static int family_registered;
-kmem_cache_t *taskstats_cache;
+struct kmem_cache *taskstats_cache;
static struct genl_family family = {
.id = GENL_ID_GENERATE,
};
static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp,
- void **replyp, size_t size)
+ size_t size)
{
struct sk_buff *skb;
void *reply;
/*
* If new attributes are added, please revisit this allocation
*/
- size = nlmsg_total_size(genlmsg_total_size(size));
- skb = nlmsg_new(size, GFP_KERNEL);
+ skb = genlmsg_new(size, GFP_KERNEL);
if (!skb)
return -ENOMEM;
int seq = get_cpu_var(taskstats_seqnum)++;
put_cpu_var(taskstats_seqnum);
- reply = genlmsg_put(skb, 0, seq,
- family.id, 0, 0,
- cmd, family.version);
+ reply = genlmsg_put(skb, 0, seq, &family, 0, cmd);
} else
- reply = genlmsg_put(skb, info->snd_pid, info->snd_seq,
- family.id, 0, 0,
- cmd, family.version);
+ reply = genlmsg_put_reply(skb, info, &family, 0, cmd);
if (reply == NULL) {
nlmsg_free(skb);
return -EINVAL;
}
*skbp = skb;
- *replyp = reply;
return 0;
}
*/
static int send_reply(struct sk_buff *skb, pid_t pid)
{
- struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data);
+ struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb));
void *reply = genlmsg_data(genlhdr);
int rc;
/*
* Send taskstats data in @skb to listeners registered for @cpu's exit data
*/
-static void send_cpu_listeners(struct sk_buff *skb, unsigned int cpu)
+static void send_cpu_listeners(struct sk_buff *skb,
+ struct listener_list *listeners)
{
- struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data);
- struct listener_list *listeners;
+ struct genlmsghdr *genlhdr = nlmsg_data(nlmsg_hdr(skb));
struct listener *s, *tmp;
struct sk_buff *skb_next, *skb_cur = skb;
void *reply = genlmsg_data(genlhdr);
}
rc = 0;
- listeners = &per_cpu(listener_array, cpu);
down_read(&listeners->sem);
list_for_each_entry(s, &listeners->list, list) {
skb_next = NULL;
} else
get_task_struct(tsk);
+ memset(stats, 0, sizeof(*stats));
/*
* Each accounting subsystem adds calls to its functions to
* fill in relevant parts of struct taskstsats as follows
if (first->signal->stats)
memcpy(stats, first->signal->stats, sizeof(*stats));
+ else
+ memset(stats, 0, sizeof(*stats));
tsk = first;
do {
return ret;
}
+static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid)
+{
+ struct nlattr *na, *ret;
+ int aggr;
+
+ aggr = (type == TASKSTATS_TYPE_PID)
+ ? TASKSTATS_TYPE_AGGR_PID
+ : TASKSTATS_TYPE_AGGR_TGID;
+
+ na = nla_nest_start(skb, aggr);
+ if (!na)
+ goto err;
+ if (nla_put(skb, type, sizeof(pid), &pid) < 0)
+ goto err;
+ ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats));
+ if (!ret)
+ goto err;
+ nla_nest_end(skb, na);
+
+ return nla_data(ret);
+err:
+ return NULL;
+}
+
static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
{
int rc = 0;
struct sk_buff *rep_skb;
- struct taskstats stats;
- void *reply;
+ struct taskstats *stats;
size_t size;
- struct nlattr *na;
cpumask_t mask;
rc = parse(info->attrs[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK], &mask);
size = nla_total_size(sizeof(u32)) +
nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
- memset(&stats, 0, sizeof(stats));
- rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, &reply, size);
+ rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
if (rc < 0)
return rc;
+ rc = -EINVAL;
if (info->attrs[TASKSTATS_CMD_ATTR_PID]) {
u32 pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]);
- rc = fill_pid(pid, NULL, &stats);
- if (rc < 0)
+ stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid);
+ if (!stats)
goto err;
- na = nla_nest_start(rep_skb, TASKSTATS_TYPE_AGGR_PID);
- NLA_PUT_U32(rep_skb, TASKSTATS_TYPE_PID, pid);
- NLA_PUT_TYPE(rep_skb, struct taskstats, TASKSTATS_TYPE_STATS,
- stats);
+ rc = fill_pid(pid, NULL, stats);
+ if (rc < 0)
+ goto err;
} else if (info->attrs[TASKSTATS_CMD_ATTR_TGID]) {
u32 tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]);
- rc = fill_tgid(tgid, NULL, &stats);
- if (rc < 0)
+ stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid);
+ if (!stats)
goto err;
- na = nla_nest_start(rep_skb, TASKSTATS_TYPE_AGGR_TGID);
- NLA_PUT_U32(rep_skb, TASKSTATS_TYPE_TGID, tgid);
- NLA_PUT_TYPE(rep_skb, struct taskstats, TASKSTATS_TYPE_STATS,
- stats);
- } else {
- rc = -EINVAL;
+ rc = fill_tgid(tgid, NULL, stats);
+ if (rc < 0)
+ goto err;
+ } else
goto err;
- }
-
- nla_nest_end(rep_skb, na);
return send_reply(rep_skb, info->snd_pid);
-
-nla_put_failure:
- rc = genlmsg_cancel(rep_skb, reply);
err:
nlmsg_free(rep_skb);
return rc;
}
-void taskstats_exit_alloc(struct taskstats **ptidstats, unsigned int *mycpu)
+static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk)
{
- struct listener_list *listeners;
- struct taskstats *tmp;
- /*
- * This is the cpu on which the task is exiting currently and will
- * be the one for which the exit event is sent, even if the cpu
- * on which this function is running changes later.
- */
- *mycpu = raw_smp_processor_id();
+ struct signal_struct *sig = tsk->signal;
+ struct taskstats *stats;
- *ptidstats = NULL;
- tmp = kmem_cache_zalloc(taskstats_cache, SLAB_KERNEL);
- if (!tmp)
- return;
+ if (sig->stats || thread_group_empty(tsk))
+ goto ret;
- listeners = &per_cpu(listener_array, *mycpu);
- down_read(&listeners->sem);
- if (!list_empty(&listeners->list)) {
- *ptidstats = tmp;
- tmp = NULL;
+ /* No problem if kmem_cache_zalloc() fails */
+ stats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
+
+ spin_lock_irq(&tsk->sighand->siglock);
+ if (!sig->stats) {
+ sig->stats = stats;
+ stats = NULL;
}
- up_read(&listeners->sem);
- kfree(tmp);
+ spin_unlock_irq(&tsk->sighand->siglock);
+
+ if (stats)
+ kmem_cache_free(taskstats_cache, stats);
+ret:
+ return sig->stats;
}
/* Send pid data out on exit */
-void taskstats_exit_send(struct task_struct *tsk, struct taskstats *tidstats,
- int group_dead, unsigned int mycpu)
+void taskstats_exit(struct task_struct *tsk, int group_dead)
{
int rc;
+ struct listener_list *listeners;
+ struct taskstats *stats;
struct sk_buff *rep_skb;
- void *reply;
size_t size;
int is_thread_group;
- struct nlattr *na;
if (!family_registered)
return;
size = nla_total_size(sizeof(u32)) +
nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
- is_thread_group = (tsk->signal->stats != NULL);
+ is_thread_group = !!taskstats_tgid_alloc(tsk);
if (is_thread_group) {
/* PID + STATS + TGID + STATS */
size = 2 * size;
fill_tgid_exit(tsk);
}
- if (!tidstats)
+ listeners = &__raw_get_cpu_var(listener_array);
+ if (list_empty(&listeners->list))
return;
- rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, &reply, size);
- if (rc < 0)
- goto ret;
-
- rc = fill_pid(tsk->pid, tsk, tidstats);
+ rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size);
if (rc < 0)
- goto err_skb;
+ return;
- na = nla_nest_start(rep_skb, TASKSTATS_TYPE_AGGR_PID);
- NLA_PUT_U32(rep_skb, TASKSTATS_TYPE_PID, (u32)tsk->pid);
- NLA_PUT_TYPE(rep_skb, struct taskstats, TASKSTATS_TYPE_STATS,
- *tidstats);
- nla_nest_end(rep_skb, na);
+ stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, tsk->pid);
+ if (!stats)
+ goto err;
- if (!is_thread_group)
- goto send;
+ rc = fill_pid(tsk->pid, tsk, stats);
+ if (rc < 0)
+ goto err;
/*
* Doesn't matter if tsk is the leader or the last group member leaving
*/
- if (!group_dead)
+ if (!is_thread_group || !group_dead)
goto send;
- na = nla_nest_start(rep_skb, TASKSTATS_TYPE_AGGR_TGID);
- NLA_PUT_U32(rep_skb, TASKSTATS_TYPE_TGID, (u32)tsk->tgid);
- /* No locking needed for tsk->signal->stats since group is dead */
- NLA_PUT_TYPE(rep_skb, struct taskstats, TASKSTATS_TYPE_STATS,
- *tsk->signal->stats);
- nla_nest_end(rep_skb, na);
+ stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tsk->tgid);
+ if (!stats)
+ goto err;
+
+ memcpy(stats, tsk->signal->stats, sizeof(*stats));
send:
- send_cpu_listeners(rep_skb, mycpu);
+ send_cpu_listeners(rep_skb, listeners);
return;
-
-nla_put_failure:
- genlmsg_cancel(rep_skb, reply);
-err_skb:
+err:
nlmsg_free(rep_skb);
-ret:
- return;
}
static struct genl_ops taskstats_ops = {
{
unsigned int i;
- taskstats_cache = kmem_cache_create("taskstats_cache",
- sizeof(struct taskstats),
- 0, SLAB_PANIC, NULL, NULL);
+ taskstats_cache = KMEM_CACHE(taskstats, SLAB_PANIC);
for_each_possible_cpu(i) {
INIT_LIST_HEAD(&(per_cpu(listener_array, i).list));
init_rwsem(&(per_cpu(listener_array, i).sem));
git.samba.org / sfrench / cifs-2.6.git / blobdiff