X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=kernel%2Ftaskstats.c;h=906cae771585f8fe0241375066393a25b7a40cea;hb=25f4a81ef51b7c279786f5b81fe6d89510f46d99;hp=2654886fe0586d7feb3fbd29baf31afa88f529f9;hpb=115085ea0794c0f339be8f9d25505c7f9861d824;p=mv-sheeva.git diff --git a/kernel/taskstats.c b/kernel/taskstats.c index 2654886fe05..906cae77158 100644 --- a/kernel/taskstats.c +++ b/kernel/taskstats.c @@ -69,7 +69,7 @@ enum actions { }; 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; @@ -94,7 +94,6 @@ static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp, } *skbp = skb; - *replyp = reply; return 0; } @@ -103,7 +102,7 @@ static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp, */ 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; @@ -122,7 +121,7 @@ static int send_reply(struct sk_buff *skb, pid_t pid) static void send_cpu_listeners(struct sk_buff *skb, struct listener_list *listeners) { - struct genlmsghdr *genlhdr = nlmsg_data((struct nlmsghdr *)skb->data); + 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); @@ -185,6 +184,7 @@ static int fill_pid(pid_t pid, struct task_struct *tsk, } 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 @@ -227,6 +227,8 @@ static int fill_tgid(pid_t tgid, struct task_struct *first, if (first->signal->stats) memcpy(stats, first->signal->stats, sizeof(*stats)); + else + memset(stats, 0, sizeof(*stats)); tsk = first; do { @@ -343,14 +345,36 @@ static int parse(struct nlattr *na, cpumask_t *mask) 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); @@ -371,58 +395,71 @@ static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info) 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; } +static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk) +{ + struct signal_struct *sig = tsk->signal; + struct taskstats *stats; + + if (sig->stats || thread_group_empty(tsk)) + goto ret; + + /* 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; + } + 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(struct task_struct *tsk, int group_dead) { int rc; struct listener_list *listeners; - struct taskstats *tidstats; + struct taskstats *stats; struct sk_buff *rep_skb; - void *reply; size_t size; int is_thread_group; - struct nlattr *na; if (!family_registered) return; @@ -433,7 +470,7 @@ void taskstats_exit(struct task_struct *tsk, int group_dead) 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; @@ -445,51 +482,35 @@ void taskstats_exit(struct task_struct *tsk, int group_dead) if (list_empty(&listeners->list)) return; - tidstats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL); - if (!tidstats) + rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size); + if (rc < 0) return; - rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, &reply, size); - if (rc < 0) - goto free_stats; + stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, tsk->pid); + if (!stats) + goto err; - rc = fill_pid(tsk->pid, tsk, tidstats); + rc = fill_pid(tsk->pid, tsk, stats); if (rc < 0) - goto err_skb; - - 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); - - if (!is_thread_group) - goto send; + 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, listeners); -free_stats: - kmem_cache_free(taskstats_cache, tidstats); return; - -nla_put_failure: - genlmsg_cancel(rep_skb, reply); -err_skb: +err: nlmsg_free(rep_skb); - goto free_stats; } static struct genl_ops taskstats_ops = { @@ -503,9 +524,7 @@ void __init taskstats_init_early(void) { 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));