* - Takes an instrumentation source as parameter
* - e.g. tracepoints, dynamic_probes...
* - Takes instrumentation source specific arguments.
+ *
+ * Dual LGPL v2.1/GPL v2 license.
*/
+#include <linux/module.h>
#include <linux/debugfs.h>
+#include <linux/anon_inodes.h>
+#include <linux/file.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */
+#include "wrapper/ringbuffer/vfs.h"
+#include "wrapper/poll.h"
+#include "ltt-debugfs-abi.h"
#include "ltt-events.h"
+#include "ltt-tracer.h"
/*
* This is LTTng's own personal way to create a system call as an external
static const struct file_operations lttng_fops;
static const struct file_operations lttng_session_fops;
static const struct file_operations lttng_channel_fops;
+static const struct file_operations lttng_metadata_fops;
static const struct file_operations lttng_event_fops;
-/*
- * LTTng DebugFS ABI structures.
- */
-
-struct lttng_channel {
- int overwrite; /* 1: overwrite, 0: discard */
- u64 subbuf_size;
- u64 num_subbuf;
- unsigned int switch_timer_interval;
- unsigned int read_timer_interval;
-};
-
-struct lttng_event {
- enum instrum_type itype;
- char name[];
+enum channel_type {
+ PER_CPU_CHANNEL,
+ METADATA_CHANNEL,
};
static
int lttng_abi_create_session(void)
{
struct ltt_session *session;
- struct file *session_filp;
- int session_fd;
+ struct file *session_file;
+ int session_fd, ret;
session = ltt_session_create();
if (!session)
return -ENOMEM;
- session_fd = get_unused_fd_flags(O_RDWR);
+ session_fd = get_unused_fd();
if (session_fd < 0) {
ret = session_fd;
goto fd_error;
}
- session_filp = anon_inode_getfile("[lttng_session]",
+ session_file = anon_inode_getfile("[lttng_session]",
<tng_session_fops,
session, O_RDWR);
- if (IS_ERR(session_filp)) {
- ret = PTR_ERR(session_filp);
+ if (IS_ERR(session_file)) {
+ ret = PTR_ERR(session_file);
goto file_error;
}
- session->file = session_filp;
- fd_install(session_fd, session_filp);
+ session->file = session_file;
+ fd_install(session_fd, session_file);
return session_fd;
file_error:
return ret;
}
+static
+int lttng_abi_tracepoint_list(void)
+{
+ struct file *tracepoint_list_file;
+ int file_fd, ret;
+
+ file_fd = get_unused_fd();
+ if (file_fd < 0) {
+ ret = file_fd;
+ goto fd_error;
+ }
+
+ tracepoint_list_file = anon_inode_getfile("[lttng_session]",
+ <tng_tracepoint_list_fops,
+ NULL, O_RDWR);
+ if (IS_ERR(tracepoint_list_file)) {
+ ret = PTR_ERR(tracepoint_list_file);
+ goto file_error;
+ }
+ ret = lttng_tracepoint_list_fops.open(NULL, tracepoint_list_file);
+ if (ret < 0)
+ goto open_error;
+ fd_install(file_fd, tracepoint_list_file);
+ if (file_fd < 0) {
+ ret = file_fd;
+ goto fd_error;
+ }
+ return file_fd;
+
+open_error:
+ fput(tracepoint_list_file);
+file_error:
+ put_unused_fd(file_fd);
+fd_error:
+ return ret;
+}
+
+static
+long lttng_abi_tracer_version(struct file *file,
+ struct lttng_kernel_tracer_version __user *uversion_param)
+{
+ struct lttng_kernel_tracer_version v;
+
+ v.version = LTTNG_VERSION;
+ v.patchlevel = LTTNG_PATCHLEVEL;
+ v.sublevel = LTTNG_SUBLEVEL;
+
+ if (copy_to_user(uversion_param, &v, sizeof(v)))
+ return -EFAULT;
+ return 0;
+}
+
+static
+long lttng_abi_add_context(struct file *file,
+ struct lttng_kernel_context __user *ucontext_param,
+ struct lttng_ctx **ctx, struct ltt_session *session)
+{
+ struct lttng_kernel_context context_param;
+
+ if (session->been_active)
+ return -EPERM;
+
+ if (copy_from_user(&context_param, ucontext_param, sizeof(context_param)))
+ return -EFAULT;
+
+ switch (context_param.ctx) {
+ case LTTNG_KERNEL_CONTEXT_PID:
+ return lttng_add_pid_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_PRIO:
+ return lttng_add_prio_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_NICE:
+ return lttng_add_nice_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_PERF_COUNTER:
+ context_param.u.perf_counter.name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ return lttng_add_perf_counter_to_ctx(context_param.u.perf_counter.type,
+ context_param.u.perf_counter.config,
+ context_param.u.perf_counter.name,
+ ctx);
+ case LTTNG_KERNEL_CONTEXT_COMM:
+ return lttng_add_comm_to_ctx(ctx);
+ default:
+ return -EINVAL;
+ }
+}
+
/**
* lttng_ioctl - lttng syscall through ioctl
*
- * @filp: the file
+ * @file: the file
* @cmd: the command
* @arg: command arg
*
* This ioctl implements lttng commands:
- * LTTNG_SESSION
+ * LTTNG_KERNEL_SESSION
* Returns a LTTng trace session file descriptor
+ * LTTNG_KERNEL_TRACER_VERSION
+ * Returns the LTTng kernel tracer version
+ * LTTNG_KERNEL_TRACEPOINT_LIST
+ * Returns a file descriptor listing available tracepoints
*
* The returned session will be deleted when its file descriptor is closed.
*/
static
-long lttng_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
switch (cmd) {
- case LTTNG_SESSION:
+ case LTTNG_KERNEL_SESSION:
return lttng_abi_create_session();
+ case LTTNG_KERNEL_TRACER_VERSION:
+ return lttng_abi_tracer_version(file,
+ (struct lttng_kernel_tracer_version __user *) arg);
+ case LTTNG_KERNEL_TRACEPOINT_LIST:
+ return lttng_abi_tracepoint_list();
default:
return -ENOIOCTLCMD;
}
#ifdef CONFIG_COMPAT
.compat_ioctl = lttng_ioctl,
#endif
+};
+
+/*
+ * We tolerate no failure in this function (if one happens, we print a dmesg
+ * error, but cannot return any error, because the channel information is
+ * invariant.
+ */
+static
+void lttng_metadata_create_events(struct file *channel_file)
+{
+ struct ltt_channel *channel = channel_file->private_data;
+ static struct lttng_kernel_event metadata_params = {
+ .instrumentation = LTTNG_KERNEL_TRACEPOINT,
+ .name = "lttng_metadata",
+ };
+ struct ltt_event *event;
+ int ret;
+
+ /*
+ * We tolerate no failure path after event creation. It will stay
+ * invariant for the rest of the session.
+ */
+ event = ltt_event_create(channel, &metadata_params, NULL);
+ if (!event) {
+ ret = -EINVAL;
+ goto create_error;
+ }
+ return;
+
+create_error:
+ WARN_ON(1);
+ return; /* not allowed to return error */
}
-int lttng_abi_create_channel(struct file *session_filp,
- struct lttng_channel __user *uchan_param)
+static
+int lttng_abi_create_channel(struct file *session_file,
+ struct lttng_kernel_channel __user *uchan_param,
+ enum channel_type channel_type)
{
- struct ltt_session *session = session_filp->private_data;
+ struct ltt_session *session = session_file->private_data;
+ const struct file_operations *fops;
+ const char *transport_name;
struct ltt_channel *chan;
- struct file *chan_filp;
- struct lttng_channel chan_param;
+ struct file *chan_file;
+ struct lttng_kernel_channel chan_param;
int chan_fd;
int ret = 0;
if (copy_from_user(&chan_param, uchan_param, sizeof(chan_param)))
return -EFAULT;
- chan_fd = get_unused_fd_flags(O_RDWR);
+ chan_fd = get_unused_fd();
if (chan_fd < 0) {
ret = chan_fd;
goto fd_error;
}
- chan_filp = anon_inode_getfile("[lttng_channel]",
+ chan_file = anon_inode_getfile("[lttng_channel]",
<tng_channel_fops,
NULL, O_RDWR);
- if (IS_ERR(chan_filp)) {
- ret = PTR_ERR(chan_filp);
+ if (IS_ERR(chan_file)) {
+ ret = PTR_ERR(chan_file);
goto file_error;
}
+ switch (channel_type) {
+ case PER_CPU_CHANNEL:
+ transport_name = chan_param.overwrite ?
+ "relay-overwrite" : "relay-discard";
+ fops = <tng_channel_fops;
+ break;
+ case METADATA_CHANNEL:
+ transport_name = "relay-metadata";
+ fops = <tng_metadata_fops;
+ break;
+ default:
+ transport_name = "<unknown>";
+ break;
+ }
/*
* We tolerate no failure path after channel creation. It will stay
* invariant for the rest of the session.
*/
- chan = ltt_channel_create(session, chan_param->overwrite, NULL,
- chan_param->subbuf_size,
- chan_param->num_subbuf,
- chan_param->switch_timer_interval,
- chan_param->read_timer_interval);
+ chan = ltt_channel_create(session, transport_name, NULL,
+ chan_param.subbuf_size,
+ chan_param.num_subbuf,
+ chan_param.switch_timer_interval,
+ chan_param.read_timer_interval);
if (!chan) {
- ret = -ENOMEM;
+ ret = -EINVAL;
goto chan_error;
}
- channel->file = chan_filp;
- chan_filp->private_data = chan;
- fd_install(chan_fd, chan_filp);
+ chan->file = chan_file;
+ chan_file->private_data = chan;
+ fd_install(chan_fd, chan_file);
+ if (channel_type == METADATA_CHANNEL) {
+ session->metadata = chan;
+ lttng_metadata_create_events(chan_file);
+ }
+
/* The channel created holds a reference on the session */
- atomic_inc(&session_filp->f_count);
+ atomic_long_inc(&session_file->f_count);
return chan_fd;
chan_error:
- fput(chan_filp);
+ fput(chan_file);
file_error:
put_unused_fd(chan_fd);
fd_error:
/**
* lttng_session_ioctl - lttng session fd ioctl
*
- * @filp: the file
+ * @file: the file
* @cmd: the command
* @arg: command arg
*
* This ioctl implements lttng commands:
- * LTTNG_CHANNEL
+ * LTTNG_KERNEL_CHANNEL
* Returns a LTTng channel file descriptor
+ * LTTNG_KERNEL_SESSION_START
+ * Starts tracing session
+ * LTTNG_KERNEL_SESSION_STOP
+ * Stops tracing session
+ * LTTNG_KERNEL_METADATA
+ * Returns a LTTng metadata file descriptor
*
* The returned channel will be deleted when its file descriptor is closed.
*/
static
-long lttng_session_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
+ struct ltt_session *session = file->private_data;
+
switch (cmd) {
- case LTTNG_CHANNEL:
- return lttng_abi_create_channel(filp, (struct lttng_channel __user *)arg);
+ case LTTNG_KERNEL_CHANNEL:
+ return lttng_abi_create_channel(file,
+ (struct lttng_kernel_channel __user *) arg,
+ PER_CPU_CHANNEL);
+ case LTTNG_KERNEL_SESSION_START:
+ return ltt_session_start(session);
+ case LTTNG_KERNEL_SESSION_STOP:
+ return ltt_session_stop(session);
+ case LTTNG_KERNEL_METADATA:
+ return lttng_abi_create_channel(file,
+ (struct lttng_kernel_channel __user *) arg,
+ METADATA_CHANNEL);
default:
return -ENOIOCTLCMD;
}
int lttng_session_release(struct inode *inode, struct file *file)
{
struct ltt_session *session = file->private_data;
- return ltt_session_destroy(session);
+
+ if (session)
+ ltt_session_destroy(session);
+ return 0;
}
static const struct file_operations lttng_session_fops = {
#ifdef CONFIG_COMPAT
.compat_ioctl = lttng_session_ioctl,
#endif
-}
+};
static
-int lttng_abi_open_stream(struct file *channel_filp)
+int lttng_abi_open_stream(struct file *channel_file)
{
- struct ltt_channel *channel = channel_filp->private_data;
+ struct ltt_channel *channel = channel_file->private_data;
struct lib_ring_buffer *buf;
int stream_fd, ret;
+ struct file *stream_file;
- buf = ltt_buffer_read_open(channel->chan);
+ buf = channel->ops->buffer_read_open(channel->chan);
if (!buf)
return -ENOENT;
- stream_fd = get_unused_fd_flags(O_RDWR);
+ stream_fd = get_unused_fd();
if (stream_fd < 0) {
ret = stream_fd;
goto fd_error;
}
- stream_filp = anon_inode_getfile("[lttng_stream]",
+ stream_file = anon_inode_getfile("[lttng_stream]",
&lib_ring_buffer_file_operations,
buf, O_RDWR);
- if (IS_ERR(stream_filp)) {
- ret = PTR_ERR(stream_filp);
+ if (IS_ERR(stream_file)) {
+ ret = PTR_ERR(stream_file);
goto file_error;
}
- fd_install(stream_fd, stream_filp);
- /* The stream holds a reference on the channel */
- atomic_inc(&channel_filp->f_count);
+ /*
+ * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
+ * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
+ * file descriptor, so we set FMODE_PREAD here.
+ */
+ stream_file->f_mode |= FMODE_PREAD;
+ fd_install(stream_fd, stream_file);
+ /*
+ * The stream holds a reference to the channel within the generic ring
+ * buffer library, so no need to hold a refcount on the channel and
+ * session files here.
+ */
return stream_fd;
file_error:
put_unused_fd(stream_fd);
fd_error:
- ltt_buffer_read_close(buf);
+ channel->ops->buffer_read_close(buf);
return ret;
}
static
-int lttng_abi_create_event(struct file *channel_filp,
- struct lttng_event __user *uevent_param)
+int lttng_abi_create_event(struct file *channel_file,
+ struct lttng_kernel_event __user *uevent_param)
{
- struct ltt_channel *channel = channel_filp->private_data;
+ struct ltt_channel *channel = channel_file->private_data;
struct ltt_event *event;
- char *event_name;
- struct lttng_event event_param;
+ struct lttng_kernel_event event_param;
int event_fd, ret;
+ struct file *event_file;
if (copy_from_user(&event_param, uevent_param, sizeof(event_param)))
return -EFAULT;
- event_name = kmalloc(PATH_MAX, GFP_KERNEL);
- if (!event_name)
- return -ENOMEM;
- if (strncpy_from_user(event_name, &uevent_param->name, PATH_MAX)) {
- ret = -EFAULT;
- goto name_error;
+ event_param.name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ switch (event_param.instrumentation) {
+ case LTTNG_KERNEL_KPROBE:
+ event_param.u.kprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ break;
+ case LTTNG_KERNEL_FUNCTION:
+ event_param.u.ftrace.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ break;
+ default:
+ break;
}
- event_name[PATH_MAX - 1] = '\0';
- event_fd = get_unused_fd_flags(O_RDWR);
+ event_fd = get_unused_fd();
if (event_fd < 0) {
ret = event_fd;
goto fd_error;
}
- event_filp = anon_inode_getfile("[lttng_event]",
- <tng_event_fops, /* TODO: filter */
+ event_file = anon_inode_getfile("[lttng_event]",
+ <tng_event_fops,
NULL, O_RDWR);
- if (IS_ERR(event_filp)) {
- ret = PTR_ERR(event_filp);
+ if (IS_ERR(event_file)) {
+ ret = PTR_ERR(event_file);
goto file_error;
}
/*
* We tolerate no failure path after event creation. It will stay
* invariant for the rest of the session.
*/
- event = ltt_event_create(channel, event_param->itype, event_name, NULL);
+ event = ltt_event_create(channel, &event_param, NULL);
if (!event) {
+ ret = -EINVAL;
goto event_error;
- ret = -EEXIST;
}
- event_filp->private_data = event;
- fd_install(event_fd, event_filp);
+ event_file->private_data = event;
+ fd_install(event_fd, event_file);
/* The event holds a reference on the channel */
- atomic_inc(&channel_filp->f_count);
- kfree(event_name);
+ atomic_long_inc(&channel_file->f_count);
return event_fd;
event_error:
- fput(event_filp);
+ fput(event_file);
file_error:
put_unused_fd(event_fd);
fd_error:
-name_error:
- kfree(event_name);
return ret;
}
/**
* lttng_channel_ioctl - lttng syscall through ioctl
*
- * @filp: the file
+ * @file: the file
* @cmd: the command
* @arg: command arg
*
* This ioctl implements lttng commands:
- * LTTNG_STREAM
+ * LTTNG_KERNEL_STREAM
* Returns an event stream file descriptor or failure.
* (typically, one event stream records events from one CPU)
- * LTTNG_EVENT
+ * LTTNG_KERNEL_EVENT
* Returns an event file descriptor or failure.
+ * LTTNG_KERNEL_CONTEXT
+ * Prepend a context field to each event in the channel
+ *
+ * Channel and event file descriptors also hold a reference on the session.
+ */
+static
+long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct ltt_channel *channel = file->private_data;
+
+ switch (cmd) {
+ case LTTNG_KERNEL_STREAM:
+ return lttng_abi_open_stream(file);
+ case LTTNG_KERNEL_EVENT:
+ return lttng_abi_create_event(file, (struct lttng_kernel_event __user *) arg);
+ case LTTNG_KERNEL_CONTEXT:
+ return lttng_abi_add_context(file,
+ (struct lttng_kernel_context __user *) arg,
+ &channel->ctx, channel->session);
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+/**
+ * lttng_metadata_ioctl - lttng syscall through ioctl
+ *
+ * @file: the file
+ * @cmd: the command
+ * @arg: command arg
+ *
+ * This ioctl implements lttng commands:
+ * LTTNG_KERNEL_STREAM
+ * Returns an event stream file descriptor or failure.
*
- * The returned session will be deleted when its file descriptor is closed.
* Channel and event file descriptors also hold a reference on the session.
*/
static
-long lttng_channel_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
switch (cmd) {
- case LTTNG_STREAM:
- return lttng_abi_open_stream(filp);
- case LTTNG_EVENT:
- return lttng_abi_create_event(filp, (struct lttng_event __user *)arg);
+ case LTTNG_KERNEL_STREAM:
+ return lttng_abi_open_stream(file);
default:
return -ENOIOCTLCMD;
}
/**
* lttng_channel_poll - lttng stream addition/removal monitoring
*
- * @filp: the file
+ * @file: the file
* @wait: poll table
*/
-unsigned int lttng_channel_poll(struct file *filp, poll_table *wait)
+unsigned int lttng_channel_poll(struct file *file, poll_table *wait)
{
- struct ltt_channel *channel = filp->private_data;
+ struct ltt_channel *channel = file->private_data;
unsigned int mask = 0;
- if (filp->f_mode & FMODE_READ) {
+ if (file->f_mode & FMODE_READ) {
poll_wait_set_exclusive(wait);
- poll_wait(filp, &channel->notify_wait, wait);
+ poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan),
+ wait);
- /* TODO: identify when the channel is being finalized. */
- if (finalized)
+ if (channel->ops->is_disabled(channel->chan))
+ return POLLERR;
+ if (channel->ops->is_finalized(channel->chan))
return POLLHUP;
else
return POLLIN | POLLRDNORM;
int lttng_channel_release(struct inode *inode, struct file *file)
{
struct ltt_channel *channel = file->private_data;
- fput(channel->session->file);
+
+ if (channel)
+ fput(channel->session->file);
return 0;
}
#ifdef CONFIG_COMPAT
.compat_ioctl = lttng_channel_ioctl,
#endif
+};
+
+static const struct file_operations lttng_metadata_fops = {
+ .release = lttng_channel_release,
+ .unlocked_ioctl = lttng_metadata_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = lttng_metadata_ioctl,
+#endif
+};
+
+/**
+ * lttng_event_ioctl - lttng syscall through ioctl
+ *
+ * @file: the file
+ * @cmd: the command
+ * @arg: command arg
+ *
+ * This ioctl implements lttng commands:
+ * LTTNG_KERNEL_STREAM
+ * Returns an event stream file descriptor or failure.
+ * (typically, one event stream records events from one CPU)
+ * LTTNG_KERNEL_EVENT
+ * Returns an event file descriptor or failure.
+ * LTTNG_KERNEL_CONTEXT
+ * Prepend a context field to each record of this event
+ */
+static
+long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct ltt_event *event = file->private_data;
+
+ switch (cmd) {
+ case LTTNG_KERNEL_CONTEXT:
+ return lttng_abi_add_context(file,
+ (struct lttng_kernel_context __user *) arg,
+ &event->ctx, event->chan->session);
+ default:
+ return -ENOIOCTLCMD;
+ }
}
static
int lttng_event_release(struct inode *inode, struct file *file)
{
struct ltt_event *event = file->private_data;
- fput(event->chan->file);
+
+ if (event)
+ fput(event->chan->file);
return 0;
}
+/* TODO: filter control ioctl */
static const struct file_operations lttng_event_fops = {
.release = lttng_event_release,
-}
+ .unlocked_ioctl = lttng_event_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = lttng_event_ioctl,
+#endif
+};
-static int __init ltt_debugfs_abi_init(void)
+int __init ltt_debugfs_abi_init(void)
{
int ret = 0;
- lttng_dentry = debugfs_create_file("lttng", NULL);
- if (IS_ERR(lttng_dentry) || !lttng_dentry)
+ wrapper_vmalloc_sync_all();
+ lttng_dentry = debugfs_create_file("lttng", S_IWUSR, NULL, NULL,
+ <tng_fops);
+ if (IS_ERR(lttng_dentry) || !lttng_dentry) {
printk(KERN_ERR "Error creating LTTng control file\n");
ret = -ENOMEM;
goto error;
return ret;
}
-static void __exit ltt_debugfs_abi_exit(void)
+void __exit ltt_debugfs_abi_exit(void)
{
- debugfs_remote(lttng_dentry);
+ debugfs_remove(lttng_dentry);
}
projects / lttng-modules.git / blobdiff