diff options
Diffstat (limited to 'runtime/transport/utt.c')
| -rw-r--r-- | runtime/transport/utt.c | 404 |
1 files changed, 0 insertions, 404 deletions
diff --git a/runtime/transport/utt.c b/runtime/transport/utt.c deleted file mode 100644 index 2dd303a5..00000000 --- a/runtime/transport/utt.c +++ /dev/null @@ -1,404 +0,0 @@ -/* -*- linux-c -*- - * - * This is a modified version of the proposed utt interface. If that - * interface makes it into the kernel, this file can go away. - * - * Copyright (C) 2006 Jens Axboe <axboe@suse.de> - * - * Moved to utt.c by Tom Zanussi, 2006 - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * 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. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - * - */ -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/percpu.h> -#include <linux/init.h> -#include <linux/debugfs.h> -#include <linux/mm.h> -#include "utt.h" - -static int utt_overwrite_flag = 0; - -/* - * utt_switch_subbuf - switch to a new sub-buffer - * - * Most of this function is deadcopy of relay_switch_subbuf. - */ -static size_t utt_switch_subbuf(struct utt_trace *utt, struct rchan_buf *buf, - size_t length) -{ - char *old, *new; - size_t old_subbuf, new_subbuf; - - if (unlikely(buf == NULL)) - return 0; - - if (unlikely(length > buf->chan->subbuf_size)) - goto toobig; - - if (buf->offset != buf->chan->subbuf_size + 1) { - buf->prev_padding = buf->chan->subbuf_size - buf->offset; - old_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; - buf->padding[old_subbuf] = buf->prev_padding; - buf->subbufs_produced++; - buf->dentry->d_inode->i_size += buf->chan->subbuf_size - - buf->padding[old_subbuf]; - smp_mb(); - if (waitqueue_active(&buf->read_wait)) - /* - * Calling wake_up_interruptible() and __mod_timer() - * from here will deadlock if we happen to be logging - * from the scheduler and timer (trying to re-grab - * rq->lock/timer->base->lock), so just set a flag. - */ - atomic_set(&utt->wakeup, 1); - } - - old = buf->data; - new_subbuf = buf->subbufs_produced % buf->chan->n_subbufs; - new = (char*)buf->start + new_subbuf * buf->chan->subbuf_size; - buf->offset = 0; - if (!buf->chan->cb->subbuf_start(buf, new, old, buf->prev_padding)) { - buf->offset = buf->chan->subbuf_size + 1; - return 0; - } - buf->data = new; - buf->padding[new_subbuf] = 0; - - if (unlikely(length + buf->offset > buf->chan->subbuf_size)) - goto toobig; - - return length; - -toobig: - buf->chan->last_toobig = length; - return 0; -} - -static void __utt_wakeup_readers(struct rchan_buf *buf) -{ - if (buf && waitqueue_active(&buf->read_wait) && - buf->subbufs_produced != buf->subbufs_consumed) - wake_up_interruptible(&buf->read_wait); -} - -static void __utt_wakeup_timer(unsigned long val) -{ - struct utt_trace *utt = (struct utt_trace *)val; - int i; - - if (atomic_read(&utt->wakeup)) { - atomic_set(&utt->wakeup, 0); - if (utt->is_global) - __utt_wakeup_readers(utt->rchan->buf[0]); - else - for_each_possible_cpu(i) - __utt_wakeup_readers(utt->rchan->buf[i]); - } - - mod_timer(&utt->timer, jiffies + UTT_TIMER_INTERVAL); -} - -static void __utt_timer_init(struct utt_trace * utt) -{ - atomic_set(&utt->wakeup, 0); - init_timer(&utt->timer); - utt->timer.expires = jiffies + UTT_TIMER_INTERVAL; - utt->timer.function = __utt_wakeup_timer; - utt->timer.data = (unsigned long)utt; - add_timer(&utt->timer); -} - -static void utt_set_overwrite(int overwrite) -{ - utt_overwrite_flag = overwrite; -} - -static void utt_remove_root(struct utt_trace *utt) -{ - if (utt->utt_tree_root) { - if (!_stp_lock_transport_dir()) { - errk("Unable to lock transport directory.\n"); - return; - } - if (simple_empty(utt->utt_tree_root)) - debugfs_remove(utt->utt_tree_root); - _stp_unlock_transport_dir(); - utt->utt_tree_root = NULL; - } -} - -static void utt_remove_tree(struct utt_trace *utt) -{ - if (utt == NULL || utt->dir == NULL) - return; - debugfs_remove(utt->dir); - utt_remove_root(utt); -} - -static struct dentry *utt_create_tree(struct utt_trace *utt, const char *root, const char *name) -{ - struct dentry *dir = NULL; - - if (root == NULL || name == NULL) - return NULL; - - if (!utt->utt_tree_root) { - utt->utt_tree_root = _stp_get_root_dir(); - if (!utt->utt_tree_root) - goto err; - } - - dir = debugfs_create_dir(name, utt->utt_tree_root); - if (!dir) - utt_remove_root(utt); -err: - return dir; -} - -static void utt_trace_cleanup(struct utt_trace *utt) -{ - if (utt == NULL) - return; - if (utt->rchan) - relay_close(utt->rchan); - if (utt->dropped_file) - debugfs_remove(utt->dropped_file); - utt_remove_tree(utt); - _stp_kfree(utt); -} - -static int utt_trace_remove(struct utt_trace *utt) -{ - if (utt->trace_state == Utt_trace_setup || - utt->trace_state == Utt_trace_stopped) - utt_trace_cleanup(utt); - - return 0; -} - -static int utt_dropped_open(struct inode *inode, struct file *filp) -{ -#ifdef STAPCONF_INODE_PRIVATE - filp->private_data = inode->i_private; -#else - filp->private_data = inode->u.generic_ip; -#endif - return 0; -} - -static ssize_t utt_dropped_read(struct file *filp, char __user *buffer, - size_t count, loff_t *ppos) -{ - struct utt_trace *utt = filp->private_data; - char buf[16]; - - snprintf(buf, sizeof(buf), "%u\n", atomic_read(&utt->dropped)); - - return simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf)); -} - -static struct file_operations utt_dropped_fops = { - .owner = THIS_MODULE, - .open = utt_dropped_open, - .read = utt_dropped_read, -}; - -/* - * Keep track of how many times we encountered a full subbuffer, to aid - * the user space app in telling how many lost events there were. - */ -static int utt_subbuf_start_callback(struct rchan_buf *buf, void *subbuf, - void *prev_subbuf, size_t prev_padding) -{ - struct utt_trace *utt; - - if (utt_overwrite_flag || !relay_buf_full(buf)) - return 1; - - utt = buf->chan->private_data; - atomic_inc(&utt->dropped); - return 0; -} - -static int utt_remove_buf_file_callback(struct dentry *dentry) -{ - debugfs_remove(dentry); - return 0; -} - -static struct dentry *utt_create_buf_file_callback(const char *filename, - struct dentry *parent, - int mode, - struct rchan_buf *buf, - int *is_global) -{ - struct dentry *file = debugfs_create_file(filename, mode, parent, buf, - &relay_file_operations); - if (file) { - file->d_inode->i_uid = _stp_uid; - file->d_inode->i_gid = _stp_gid; - } - return file; -} - -static struct dentry *utt_create_global_buf_file_callback(const char *filename, - struct dentry *parent, - int mode, - struct rchan_buf *buf, - int *is_global) -{ - struct dentry *file; - *is_global = 1; - file = debugfs_create_file(filename, mode, parent, buf, - &relay_file_operations); - if (file) { - file->d_inode->i_uid = _stp_uid; - file->d_inode->i_gid = _stp_gid; - } - return file; -} - -static struct rchan_callbacks utt_relay_callbacks = { - .subbuf_start = utt_subbuf_start_callback, - .create_buf_file = utt_create_buf_file_callback, - .remove_buf_file = utt_remove_buf_file_callback, -}; - -static struct rchan_callbacks utt_relay_callbacks_global = { - .subbuf_start = utt_subbuf_start_callback, - .create_buf_file = utt_create_global_buf_file_callback, - .remove_buf_file = utt_remove_buf_file_callback, -}; - -/* - * Setup everything required to start tracing - */ -static struct utt_trace *utt_trace_setup(struct utt_trace_setup *utts) -{ - struct utt_trace *utt = NULL; - struct dentry *dir = NULL; - int ret = -EINVAL; - u64 npages; - struct sysinfo si; - - if (!utts->buf_size || !utts->buf_nr) - goto err; - - ret = -ENOMEM; - utt = _stp_kzalloc(sizeof(*utt)); - if (!utt) - goto err; - - ret = -ENOENT; - dir = utt_create_tree(utt, utts->root, utts->name); - if (!dir) - goto err; - utt->dir = dir; - atomic_set(&utt->dropped, 0); - - ret = -EIO; - utt->dropped_file = debugfs_create_file("dropped", 0444, dir, utt, &utt_dropped_fops); - if (!utt->dropped_file) - goto err; - - npages = utts->buf_size * utts->buf_nr; - if (!utts->is_global) - npages *= num_possible_cpus(); - npages >>= PAGE_SHIFT; - si_meminfo(&si); -#define MB(i) (unsigned long)((i) >> (20 - PAGE_SHIFT)) - if (npages > (si.freeram + si.bufferram)) { - errk("Not enough free+buffered memory(%luMB) for log buffer(%luMB)\n", - MB(si.freeram + si.bufferram), - MB(npages)); - ret = -ENOMEM; - goto err; - } else if (npages > si.freeram) { - /* exceeds freeram, but below freeram+bufferram */ - printk(KERN_WARNING - "log buffer size exceeds free memory(%luMB)\n", - MB(si.freeram)); - } - -#if (RELAYFS_CHANNEL_VERSION >= 7) - if (utts->is_global) - utt->rchan = relay_open("trace", dir, utts->buf_size, utts->buf_nr, - &utt_relay_callbacks_global, NULL); - else - utt->rchan = relay_open("trace", dir, utts->buf_size, utts->buf_nr, - &utt_relay_callbacks, NULL); -#else - if (utts->is_global) - utt->rchan = relay_open("trace", dir, utts->buf_size, utts->buf_nr, &utt_relay_callbacks_global); - else - utt->rchan = relay_open("trace", dir, utts->buf_size, utts->buf_nr, &utt_relay_callbacks); -#endif - - if (!utt->rchan) - goto err; - utt->rchan->private_data = utt; - - utt->is_global = utts->is_global; - - utt->trace_state = Utt_trace_setup; - - utts->err = 0; - return utt; -err: - if (utt) { - if (utt->dropped_file) - debugfs_remove(utt->dropped_file); - if (utt->rchan) - relay_close(utt->rchan); - _stp_kfree(utt); - } - if (dir) - utt_remove_tree(utt); - utts->err = ret; - return NULL; -} - -static int utt_trace_startstop(struct utt_trace *utt, int start, - unsigned int *trace_seq) -{ - int ret; - - /* - * For starting a trace, we can transition from a setup or stopped - * trace. For stopping a trace, the state must be running - */ - ret = -EINVAL; - if (start) { - if (utt->trace_state == Utt_trace_setup || - utt->trace_state == Utt_trace_stopped) { - if (trace_seq) - (*trace_seq)++; - __utt_timer_init(utt); - smp_mb(); - utt->trace_state = Utt_trace_running; - ret = 0; - } - } else { - if (utt->trace_state == Utt_trace_running) { - utt->trace_state = Utt_trace_stopped; - del_timer_sync(&utt->timer); - relay_flush(utt->rchan); - ret = 0; - } - } - - return ret; -} |