+ *
+ * Copyright (C) Shailabh Nagar, IBM Corp. 2005
+ * Based on work by Matt Helsley, Nguyen Anh Quynh and Guillaume Thouvenin
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/cn_stats.h>
+#include <asm/atomic.h>
+
+#define CN_STATS_NOCPU (-1)
+#define CN_STATS_NOACK 0
+#define CN_STATS_MSG_SIZE (sizeof(struct cn_msg) + sizeof(struct cnstats))
+
+static atomic_t cnstats_num_listeners = ATOMIC_INIT(0);
+static struct cb_id cnstats_id = { CN_IDX_STATS, CN_VAL_STATS };
+/* cnstats_counts is used as the sequence number of the netlink message */
+static DEFINE_PER_CPU(__u32, cnstats_counts) = { 0 };
+
+void cnstats_init_msg(struct cn_msg *msg, int seq, int ack)
+{
+ memset(msg, 0, CN_STATS_MSG_SIZE);
+ msg->seq = seq;
+ msg->ack = ack;
+ memcpy(&msg->id, &cnstats_id, sizeof(msg->id));
+ msg->len = sizeof(struct cnstats);
+}
+
+/*
+ * Accumalate one task's statistics
+ *
+ */
+static inline void cnstats_add_tsk_data(struct cnstats_data *d, struct task_struct *tsk)
+{
+ uint64_t tmp;
+
+ d->pid = tsk->pid;
+ d->tgid = tsk->tgid;
+
+ /* zero XXX_total,non-zero XXX_count implies XXX stat overflowed */
+#ifdef CONFIG_SCHEDSTATS
+ d->cpu_count += tsk->sched_info.pcnt;
+ tmp = d->cpu_run_total + jiffies_to_usecs(tsk->sched_info.cpu_time)*1000;
+ d->cpu_run_total = (tmp < d->cpu_run_total)? 0:tmp;
+ tmp = d->cpu_delay_total + jiffies_to_usecs(tsk->sched_info.run_delay)*1000;
+ d->cpu_delay_total = (tmp < d->cpu_delay_total)? 0:tmp;
+#else
+ /* Non-zero XXX_total,zero XXX_count implies XXX stat unavailable */
+ d->cpu_count = 0;
+ d->cpu_run_total = d->cpu_delay_total = CNSTATS_NOCPUSTATS;
+#endif
+ spin_lock(&tsk->delays.lock);
+ tmp = d->blkio_delay_total + tsk->delays.blkio_delay;
+ d->blkio_delay_total = (tmp < d->blkio_delay_total)? 0:tmp;
+ tmp = d->swapin_delay_total + tsk->delays.swapin_delay;
+ d->swapin_delay_total = (tmp < d->swapin_delay_total)? 0:tmp;
+ d->blkio_count += tsk->delays.blkio_count;
+ d->swapin_count += tsk->delays.swapin_count;
+ spin_unlock(&tsk->delays.lock);
+}
+
+/*
+ * Send acknowledgement (error)
+ *
+ */
+static void cnstats_send_ack(int err, int rcvd_seq, int rcvd_ack)
+{
+ __u8 buffer[CN_STATS_MSG_SIZE];
+ struct cn_msg *msg = (struct cn_msg *)buffer;
+ struct cnstats *c = (struct cnstats *)msg->data;
+
+ cnstats_init_msg(msg, rcvd_seq, rcvd_ack+1);
+ c->version = CNSTATS_DATA_VERSION;
+ c->outtype = CNSTATS_DATA_NONE;
+
+ /* Following allows other functions to continue returning -ve errors */
+ c->data.ack.err = abs(err);
+
+ cn_netlink_send(msg, CN_IDX_STATS, GFP_KERNEL);
+}
+
+/*
+ * Send one pid's stats
+ *
+ */
+static int cnstats_send_pid(pid_t pid, int seq, int ack)
+{
+ __u8 buffer[CN_STATS_MSG_SIZE];
+ struct cn_msg *msg = (struct cn_msg *)buffer;
+ struct cnstats *c = (struct cnstats *)msg->data;
+ struct cnstats_data *d = (struct cnstats_data *)&c->data.stats;
+ struct task_struct *tsk;
+
+ cnstats_init_msg(msg, seq, ack);
+ c->version = CNSTATS_DATA_VERSION;
+ c->outtype = CNSTATS_DATA_PID;
+
+ read_lock(&tasklist_lock);
+ tsk = find_task_by_pid(pid);
+ if (!tsk) {
+ read_unlock(&tasklist_lock);
+ return -ESRCH;
+ }
+ get_task_struct(tsk);
+ read_unlock(&tasklist_lock);
+
+ cnstats_add_tsk_data(d, tsk);
+ put_task_struct(tsk);
+
+ return cn_netlink_send(msg, CN_IDX_STATS, GFP_KERNEL);
+}
+
+/*
+ * Send one tgid's stats (sum of appropriate per-pid stats)
+ *
+ */
+static int cnstats_send_tgid(pid_t tgid, int seq, int ack)
+{
+ __u8 buffer[CN_STATS_MSG_SIZE];
+ struct cn_msg *msg = (struct cn_msg *)buffer;;
+ struct cnstats *c = (struct cnstats *)msg->data;
+ struct cnstats_data *d = (struct cnstats_data *)&c->data.stats;
+ struct task_struct *first, *tsk;
+
+ cnstats_init_msg(msg, seq, ack);
+ c->version = CNSTATS_DATA_VERSION;
+ c->outtype = CNSTATS_DATA_TGID;
+
+ read_lock(&tasklist_lock);
+ first = tsk = find_task_by_pid(tgid);
+ if (!first) {
+ read_unlock(&tasklist_lock);
+ return -ESRCH;
+ }
+ do
+ cnstats_add_tsk_data(d, tsk);
+ while_each_thread(first, tsk);
+ read_unlock(&tasklist_lock);
+
+ d->pid = -1;
+ d->tgid = tgid;
+
+ return cn_netlink_send(msg, CN_IDX_STATS, GFP_KERNEL);
+}
+
+/***
+ * cnstats_ctl - handle command sent via CN_IDX_STATS connector
+ * @data: command
+ */
+static void cnstats_ctl(void *data)
+{
+ struct cn_msg *msg = data;
+ struct cnstats_cmd *cmd;
+ int err = 0;
+
+ if (msg->len != sizeof(*cmd))
+ return;
+
+ cmd = (struct cnstats_cmd *)msg->data;
+ switch (cmd->intype) {
+ case CNSTATS_CMD_LISTEN:
+ atomic_inc(&cnstats_num_listeners);
+ break;
+
+ case CNSTATS_CMD_IGNORE:
+ atomic_dec(&cnstats_num_listeners);
+ break;
+
+ case CNSTATS_CMD_STATS_PID:
+ if (atomic_read(&cnstats_num_listeners) < 1)
+ return;
+ err = cnstats_send_pid(cmd->param.pid, msg->seq, msg->ack+1);
+ if (!err)
+ return;
+ break;
+
+ case CNSTATS_CMD_STATS_TGID:
+ if (atomic_read(&cnstats_num_listeners) < 1)
+ return;
+ err = cnstats_send_tgid(cmd->param.pid, msg->seq, msg->ack+1);
+ if (!err)
+ return;
+ break;
+
+ default:
+ err = -EINVAL;
+ break;
+ }
+ cnstats_send_ack(err, msg->seq, msg->ack);
+}
+
+/***
+ * cnstats_exit_connector - send task's statistics to userspace when it exits
+ * @tsk: exiting task
+ */
+void cnstats_exit_connector(struct task_struct *tsk)
+{
+ int seq;
+ __u8 buffer[CN_STATS_MSG_SIZE];
+ struct cn_msg *msg = (struct cn_msg *)buffer;
+ struct cnstats *c = (struct cnstats *)msg->data;
+ struct cnstats_data *d = (struct cnstats_data *)&c->data.stats;
+
+ if (atomic_read(&cnstats_num_listeners) < 1)
+ return;
+
+ seq = get_cpu_var(cnstats_counts)++;
+ put_cpu_var(cnstats_counts);
+
+ cnstats_init_msg(msg, seq, CN_STATS_NOACK);
+ c->version = CNSTATS_DATA_VERSION;
+ c->outtype = CNSTATS_DATA_EXIT;
+ cnstats_add_tsk_data(d, tsk);
+
+ cn_netlink_send(msg, CN_IDX_STATS, GFP_KERNEL);
+}
+
+static int __init cnstats_init(void)
+{
+ int err;
+
+ if ((err = cn_add_callback(&cnstats_id, "cn_stats", &cnstats_ctl))) {
+ printk(KERN_WARNING "cn_stats failed to register\n");
+ return err;
+ }
+ return 0;
+}
+
+module_init(cnstats_init);
Index: linux-2.6.15-rc7/kernel/exit.c
===================================================================
--- linux-2.6.15-rc7.orig/kernel/exit.c
+++ linux-2.6.15-rc7/kernel/exit.c
@@ -29,6 +29,7 @@
#include <linux/syscalls.h>
#include <linux/signal.h>
#include <linux/cn_proc.h>
+#include <linux/cn_stats.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
@@ -865,6 +866,7 @@ fastcall NORET_TYPE void do_exit(long co
tsk->exit_code = code;
proc_exit_connector(tsk);
+ cnstats_exit_connector(tsk);
