#include <lttng/tracer.h>
#include <lttng/tp-mempool.h>
#include <ringbuffer/frontend_types.h>
+#include <ringbuffer/iterator.h>
/*
* This is LTTng's own personal way to create a system call as an external
#endif
static const struct file_operations lttng_session_fops;
+static const struct file_operations lttng_event_notifier_group_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;
return ret;
}
+void event_notifier_send_notification_work_wakeup(struct irq_work *entry)
+{
+ struct lttng_event_notifier_group *event_notifier_group =
+ container_of(entry, struct lttng_event_notifier_group,
+ wakeup_pending);
+ wake_up_interruptible(&event_notifier_group->read_wait);
+}
+
+static
+int lttng_abi_create_event_notifier_group(void)
+{
+ struct lttng_event_notifier_group *event_notifier_group;
+ struct file *event_notifier_group_file;
+ int event_notifier_group_fd, ret;
+
+ event_notifier_group = lttng_event_notifier_group_create();
+ if (!event_notifier_group)
+ return -ENOMEM;
+
+ event_notifier_group_fd = lttng_get_unused_fd();
+ if (event_notifier_group_fd < 0) {
+ ret = event_notifier_group_fd;
+ goto fd_error;
+ }
+ event_notifier_group_file = anon_inode_getfile("[lttng_event_notifier_group]",
+ <tng_event_notifier_group_fops,
+ event_notifier_group, O_RDWR);
+ if (IS_ERR(event_notifier_group_file)) {
+ ret = PTR_ERR(event_notifier_group_file);
+ goto file_error;
+ }
+
+ event_notifier_group->file = event_notifier_group_file;
+ init_waitqueue_head(&event_notifier_group->read_wait);
+ init_irq_work(&event_notifier_group->wakeup_pending,
+ event_notifier_send_notification_work_wakeup);
+ fd_install(event_notifier_group_fd, event_notifier_group_file);
+ return event_notifier_group_fd;
+
+file_error:
+ put_unused_fd(event_notifier_group_fd);
+fd_error:
+ lttng_event_notifier_group_destroy(event_notifier_group);
+ return ret;
+}
+
static
int lttng_abi_tracepoint_list(void)
{
* Returns after all previously running probes have completed
* LTTNG_KERNEL_TRACER_ABI_VERSION
* Returns the LTTng kernel tracer ABI version
+ * LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_CREATE
+ * Returns a LTTng event notifier group file descriptor
*
* The returned session will be deleted when its file descriptor is closed.
*/
case LTTNG_KERNEL_OLD_SESSION:
case LTTNG_KERNEL_SESSION:
return lttng_abi_create_session();
+ case LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_CREATE:
+ return lttng_abi_create_event_notifier_group();
case LTTNG_KERNEL_OLD_TRACER_VERSION:
{
struct lttng_kernel_tracer_version v;
#endif
};
+/*
+ * When encountering empty buffer, flush current sub-buffer if non-empty
+ * and retry (if new data available to read after flush).
+ */
+static
+ssize_t lttng_event_notifier_group_notif_read(struct file *filp, char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct lttng_event_notifier_group *event_notifier_group = filp->private_data;
+ struct channel *chan = event_notifier_group->chan;
+ struct lib_ring_buffer *buf = event_notifier_group->buf;
+ ssize_t read_count = 0, len;
+ size_t read_offset;
+
+ might_sleep();
+ if (!lttng_access_ok(VERIFY_WRITE, user_buf, count))
+ return -EFAULT;
+
+ /* Finish copy of previous record */
+ if (*ppos != 0) {
+ if (read_count < count) {
+ len = chan->iter.len_left;
+ read_offset = *ppos;
+ goto skip_get_next;
+ }
+ }
+
+ while (read_count < count) {
+ size_t copy_len, space_left;
+
+ len = lib_ring_buffer_get_next_record(chan, buf);
+len_test:
+ if (len < 0) {
+ /*
+ * Check if buffer is finalized (end of file).
+ */
+ if (len == -ENODATA) {
+ /* A 0 read_count will tell about end of file */
+ goto nodata;
+ }
+ if (filp->f_flags & O_NONBLOCK) {
+ if (!read_count)
+ read_count = -EAGAIN;
+ goto nodata;
+ } else {
+ int error;
+
+ /*
+ * No data available at the moment, return what
+ * we got.
+ */
+ if (read_count)
+ goto nodata;
+
+ /*
+ * Wait for returned len to be >= 0 or -ENODATA.
+ */
+ error = wait_event_interruptible(
+ event_notifier_group->read_wait,
+ ((len = lib_ring_buffer_get_next_record(
+ chan, buf)), len != -EAGAIN));
+ CHAN_WARN_ON(chan, len == -EBUSY);
+ if (error) {
+ read_count = error;
+ goto nodata;
+ }
+ CHAN_WARN_ON(chan, len < 0 && len != -ENODATA);
+ goto len_test;
+ }
+ }
+ read_offset = buf->iter.read_offset;
+skip_get_next:
+ space_left = count - read_count;
+ if (len <= space_left) {
+ copy_len = len;
+ chan->iter.len_left = 0;
+ *ppos = 0;
+ } else {
+ copy_len = space_left;
+ chan->iter.len_left = len - copy_len;
+ *ppos = read_offset + copy_len;
+ }
+ if (__lib_ring_buffer_copy_to_user(&buf->backend, read_offset,
+ &user_buf[read_count],
+ copy_len)) {
+ /*
+ * Leave the len_left and ppos values at their current
+ * state, as we currently have a valid event to read.
+ */
+ return -EFAULT;
+ }
+ read_count += copy_len;
+ }
+ goto put_record;
+
+nodata:
+ *ppos = 0;
+ chan->iter.len_left = 0;
+
+put_record:
+ lib_ring_buffer_put_current_record(buf);
+ return read_count;
+}
+
+/*
+ * If the ring buffer is non empty (even just a partial subbuffer), return that
+ * there is data available. Perform a ring buffer flush if we encounter a
+ * non-empty ring buffer which does not have any consumeable subbuffer available.
+ */
+static
+unsigned int lttng_event_notifier_group_notif_poll(struct file *filp,
+ poll_table *wait)
+{
+ unsigned int mask = 0;
+ struct lttng_event_notifier_group *event_notifier_group = filp->private_data;
+ struct channel *chan = event_notifier_group->chan;
+ struct lib_ring_buffer *buf = event_notifier_group->buf;
+ const struct lib_ring_buffer_config *config = &chan->backend.config;
+ int finalized, disabled;
+ unsigned long consumed, offset;
+ size_t subbuffer_header_size = config->cb.subbuffer_header_size();
+
+ if (filp->f_mode & FMODE_READ) {
+ poll_wait_set_exclusive(wait);
+ poll_wait(filp, &event_notifier_group->read_wait, wait);
+
+ finalized = lib_ring_buffer_is_finalized(config, buf);
+ disabled = lib_ring_buffer_channel_is_disabled(chan);
+
+ /*
+ * lib_ring_buffer_is_finalized() contains a smp_rmb() ordering
+ * finalized load before offsets loads.
+ */
+ WARN_ON(atomic_long_read(&buf->active_readers) != 1);
+retry:
+ if (disabled)
+ return POLLERR;
+
+ offset = lib_ring_buffer_get_offset(config, buf);
+ consumed = lib_ring_buffer_get_consumed(config, buf);
+
+ /*
+ * If there is no buffer available to consume.
+ */
+ if (subbuf_trunc(offset, chan) - subbuf_trunc(consumed, chan) == 0) {
+ /*
+ * If there is a non-empty subbuffer, flush and try again.
+ */
+ if (subbuf_offset(offset, chan) > subbuffer_header_size) {
+ lib_ring_buffer_switch_remote(buf);
+ goto retry;
+ }
+
+ if (finalized)
+ return POLLHUP;
+ else {
+ /*
+ * The memory barriers
+ * __wait_event()/wake_up_interruptible() take
+ * care of "raw_spin_is_locked" memory ordering.
+ */
+ if (raw_spin_is_locked(&buf->raw_tick_nohz_spinlock))
+ goto retry;
+ else
+ return 0;
+ }
+ } else {
+ if (subbuf_trunc(offset, chan) - subbuf_trunc(consumed, chan)
+ >= chan->backend.buf_size)
+ return POLLPRI | POLLRDBAND;
+ else
+ return POLLIN | POLLRDNORM;
+ }
+ }
+
+ return mask;
+}
+
+/**
+ * lttng_event_notifier_group_notif_open - event_notifier ring buffer open file operation
+ * @inode: opened inode
+ * @file: opened file
+ *
+ * Open implementation. Makes sure only one open instance of a buffer is
+ * done at a given moment.
+ */
+static int lttng_event_notifier_group_notif_open(struct inode *inode, struct file *file)
+{
+ struct lttng_event_notifier_group *event_notifier_group = inode->i_private;
+ struct lib_ring_buffer *buf = event_notifier_group->buf;
+
+ file->private_data = event_notifier_group;
+ return lib_ring_buffer_open(inode, file, buf);
+}
+
+/**
+ * lttng_event_notifier_group_notif_release - event_notifier ring buffer release file operation
+ * @inode: opened inode
+ * @file: opened file
+ *
+ * Release implementation.
+ */
+static int lttng_event_notifier_group_notif_release(struct inode *inode, struct file *file)
+{
+ struct lttng_event_notifier_group *event_notifier_group = file->private_data;
+ struct lib_ring_buffer *buf = event_notifier_group->buf;
+ int ret;
+
+ ret = lib_ring_buffer_release(inode, file, buf);
+ if (ret)
+ return ret;
+ fput(event_notifier_group->file);
+ return 0;
+}
+
+static const struct file_operations lttng_event_notifier_group_notif_fops = {
+ .owner = THIS_MODULE,
+ .open = lttng_event_notifier_group_notif_open,
+ .release = lttng_event_notifier_group_notif_release,
+ .read = lttng_event_notifier_group_notif_read,
+ .poll = lttng_event_notifier_group_notif_poll,
+};
+
/**
* lttng_metadata_ring_buffer_poll - LTTng ring buffer poll file operation
* @filp: the file
static
int lttng_abi_create_stream_fd(struct file *channel_file, void *stream_priv,
- const struct file_operations *fops)
+ const struct file_operations *fops, const char *name)
{
int stream_fd, ret;
struct file *stream_file;
ret = stream_fd;
goto fd_error;
}
- stream_file = anon_inode_getfile("[lttng_stream]", fops,
- stream_priv, O_RDWR);
+ stream_file = anon_inode_getfile(name, fops, stream_priv, O_RDWR);
if (IS_ERR(stream_file)) {
ret = PTR_ERR(stream_file);
goto file_error;
stream_priv = buf;
ret = lttng_abi_create_stream_fd(channel_file, stream_priv,
- <tng_stream_ring_buffer_file_operations);
+ <tng_stream_ring_buffer_file_operations,
+ "[lttng_stream]");
if (ret < 0)
goto fd_error;
}
ret = lttng_abi_create_stream_fd(channel_file, stream_priv,
- <tng_metadata_ring_buffer_file_operations);
+ <tng_metadata_ring_buffer_file_operations,
+ "[lttng_metadata_stream]");
if (ret < 0)
goto fd_error;
return ret;
}
+static
+int lttng_abi_open_event_notifier_group_stream(struct file *notif_file)
+{
+ struct lttng_event_notifier_group *event_notifier_group = notif_file->private_data;
+ struct channel *chan = event_notifier_group->chan;
+ struct lib_ring_buffer *buf;
+ int ret;
+ void *stream_priv;
+
+ buf = event_notifier_group->ops->buffer_read_open(chan);
+ if (!buf)
+ return -ENOENT;
+
+ /* The event_notifier notification fd holds a reference on the event_notifier group */
+ if (!atomic_long_add_unless(¬if_file->f_count, 1, LONG_MAX)) {
+ ret = -EOVERFLOW;
+ goto refcount_error;
+ }
+ event_notifier_group->buf = buf;
+ stream_priv = event_notifier_group;
+ ret = lttng_abi_create_stream_fd(notif_file, stream_priv,
+ <tng_event_notifier_group_notif_fops,
+ "[lttng_event_notifier_stream]");
+ if (ret < 0)
+ goto fd_error;
+
+ return ret;
+
+fd_error:
+ atomic_long_dec(¬if_file->f_count);
+refcount_error:
+ event_notifier_group->ops->buffer_read_close(buf);
+ return ret;
+}
+
static
int lttng_abi_validate_event_param(struct lttng_kernel_event *event_param)
{
goto event_error;
if (event_param->instrumentation == LTTNG_KERNEL_TRACEPOINT
|| event_param->instrumentation == LTTNG_KERNEL_SYSCALL) {
- struct lttng_enabler *enabler;
+ struct lttng_event_enabler *event_enabler;
if (strutils_is_star_glob_pattern(event_param->name)) {
/*
* If the event name is a star globbing pattern,
* we create the special star globbing enabler.
*/
- enabler = lttng_enabler_create(LTTNG_ENABLER_STAR_GLOB,
+ event_enabler = lttng_event_enabler_create(LTTNG_ENABLER_FORMAT_STAR_GLOB,
event_param, channel);
} else {
- enabler = lttng_enabler_create(LTTNG_ENABLER_NAME,
+ event_enabler = lttng_event_enabler_create(LTTNG_ENABLER_FORMAT_NAME,
event_param, channel);
}
- priv = enabler;
+ priv = event_enabler;
} else {
struct lttng_event *event;
return ret;
}
+static
+long lttng_event_notifier_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct lttng_event_notifier *event_notifier;
+ struct lttng_event_notifier_enabler *event_notifier_enabler;
+ enum lttng_event_type *evtype = file->private_data;
+
+ switch (cmd) {
+ case LTTNG_KERNEL_ENABLE:
+ switch (*evtype) {
+ case LTTNG_TYPE_EVENT:
+ event_notifier = file->private_data;
+ return lttng_event_notifier_enable(event_notifier);
+ case LTTNG_TYPE_ENABLER:
+ event_notifier_enabler = file->private_data;
+ return lttng_event_notifier_enabler_enable(event_notifier_enabler);
+ default:
+ WARN_ON_ONCE(1);
+ return -ENOSYS;
+ }
+ case LTTNG_KERNEL_DISABLE:
+ switch (*evtype) {
+ case LTTNG_TYPE_EVENT:
+ event_notifier = file->private_data;
+ return lttng_event_notifier_disable(event_notifier);
+ case LTTNG_TYPE_ENABLER:
+ event_notifier_enabler = file->private_data;
+ return lttng_event_notifier_enabler_disable(event_notifier_enabler);
+ default:
+ WARN_ON_ONCE(1);
+ return -ENOSYS;
+ }
+ case LTTNG_KERNEL_FILTER:
+ switch (*evtype) {
+ case LTTNG_TYPE_EVENT:
+ return -EINVAL;
+ case LTTNG_TYPE_ENABLER:
+ event_notifier_enabler = file->private_data;
+ return lttng_event_notifier_enabler_attach_bytecode(event_notifier_enabler,
+ (struct lttng_kernel_filter_bytecode __user *) arg);
+ default:
+ WARN_ON_ONCE(1);
+ return -ENOSYS;
+ }
+ case LTTNG_KERNEL_ADD_CALLSITE:
+ switch (*evtype) {
+ case LTTNG_TYPE_EVENT:
+ event_notifier = file->private_data;
+ return lttng_event_notifier_add_callsite(event_notifier,
+ (struct lttng_kernel_event_callsite __user *) arg);
+ case LTTNG_TYPE_ENABLER:
+ return -EINVAL;
+ default:
+ WARN_ON_ONCE(1);
+ return -ENOSYS;
+ }
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+static
+int lttng_event_notifier_release(struct inode *inode, struct file *file)
+{
+ struct lttng_event_notifier *event_notifier;
+ struct lttng_event_notifier_enabler *event_notifier_enabler;
+ enum lttng_event_type *evtype = file->private_data;
+
+ if (!evtype)
+ return 0;
+
+ switch (*evtype) {
+ case LTTNG_TYPE_EVENT:
+ event_notifier = file->private_data;
+ if (event_notifier)
+ fput(event_notifier->group->file);
+ break;
+ case LTTNG_TYPE_ENABLER:
+ event_notifier_enabler = file->private_data;
+ if (event_notifier_enabler)
+ fput(event_notifier_enabler->group->file);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ break;
+ }
+
+ return 0;
+}
+
+static const struct file_operations lttng_event_notifier_fops = {
+ .owner = THIS_MODULE,
+ .release = lttng_event_notifier_release,
+ .unlocked_ioctl = lttng_event_notifier_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = lttng_event_notifier_ioctl,
+#endif
+};
+
+static
+int lttng_abi_create_event_notifier(struct file *event_notifier_group_file,
+ struct lttng_kernel_event_notifier *event_notifier_param)
+{
+ struct lttng_event_notifier_group *event_notifier_group =
+ event_notifier_group_file->private_data;
+ int event_notifier_fd, ret;
+ struct file *event_notifier_file;
+ void *priv;
+
+ switch (event_notifier_param->event.instrumentation) {
+ case LTTNG_KERNEL_TRACEPOINT:
+ case LTTNG_KERNEL_UPROBE:
+ break;
+ case LTTNG_KERNEL_KPROBE:
+ event_notifier_param->event.u.kprobe.symbol_name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
+ break;
+ case LTTNG_KERNEL_KRETPROBE:
+ /* Placing an event notifier on kretprobe is not supported. */
+ case LTTNG_KERNEL_FUNCTION:
+ case LTTNG_KERNEL_NOOP:
+ case LTTNG_KERNEL_SYSCALL:
+ default:
+ ret = -EINVAL;
+ goto inval_instr;
+ }
+
+ event_notifier_param->event.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
+
+ event_notifier_fd = lttng_get_unused_fd();
+ if (event_notifier_fd < 0) {
+ ret = event_notifier_fd;
+ goto fd_error;
+ }
+
+ event_notifier_file = anon_inode_getfile("[lttng_event_notifier]",
+ <tng_event_notifier_fops,
+ NULL, O_RDWR);
+ if (IS_ERR(event_notifier_file)) {
+ ret = PTR_ERR(event_notifier_file);
+ goto file_error;
+ }
+
+ /* The event notifier holds a reference on the event notifier group. */
+ if (!atomic_long_add_unless(&event_notifier_group_file->f_count, 1, LONG_MAX)) {
+ ret = -EOVERFLOW;
+ goto refcount_error;
+ }
+
+ if (event_notifier_param->event.instrumentation == LTTNG_KERNEL_TRACEPOINT
+ || event_notifier_param->event.instrumentation == LTTNG_KERNEL_SYSCALL) {
+ struct lttng_event_notifier_enabler *enabler;
+
+ if (strutils_is_star_glob_pattern(event_notifier_param->event.name)) {
+ /*
+ * If the event name is a star globbing pattern,
+ * we create the special star globbing enabler.
+ */
+ enabler = lttng_event_notifier_enabler_create(
+ event_notifier_group,
+ LTTNG_ENABLER_FORMAT_STAR_GLOB,
+ event_notifier_param);
+ } else {
+ enabler = lttng_event_notifier_enabler_create(
+ event_notifier_group,
+ LTTNG_ENABLER_FORMAT_NAME,
+ event_notifier_param);
+ }
+ priv = enabler;
+ } else {
+ struct lttng_event_notifier *event_notifier;
+
+ /*
+ * We tolerate no failure path after event notifier creation.
+ * It will stay invariant for the rest of the session.
+ */
+ event_notifier = lttng_event_notifier_create(NULL,
+ event_notifier_param->event.token, event_notifier_group,
+ event_notifier_param, NULL,
+ event_notifier_param->event.instrumentation);
+ WARN_ON_ONCE(!event_notifier);
+ if (IS_ERR(event_notifier)) {
+ ret = PTR_ERR(event_notifier);
+ goto event_notifier_error;
+ }
+ priv = event_notifier;
+ }
+ event_notifier_file->private_data = priv;
+ fd_install(event_notifier_fd, event_notifier_file);
+ return event_notifier_fd;
+
+event_notifier_error:
+ atomic_long_dec(&event_notifier_group_file->f_count);
+refcount_error:
+ fput(event_notifier_file);
+file_error:
+ put_unused_fd(event_notifier_fd);
+fd_error:
+inval_instr:
+ return ret;
+}
+
+static
+long lttng_event_notifier_group_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ switch (cmd) {
+ case LTTNG_KERNEL_EVENT_NOTIFIER_GROUP_NOTIFICATION_FD:
+ {
+ return lttng_abi_open_event_notifier_group_stream(file);
+ }
+ case LTTNG_KERNEL_EVENT_NOTIFIER_CREATE:
+ {
+ struct lttng_kernel_event_notifier uevent_notifier_param;
+
+ if (copy_from_user(&uevent_notifier_param,
+ (struct lttng_kernel_event_notifier __user *) arg,
+ sizeof(uevent_notifier_param)))
+ return -EFAULT;
+ return lttng_abi_create_event_notifier(file, &uevent_notifier_param);
+ }
+ default:
+ return -ENOIOCTLCMD;
+ }
+ return 0;
+}
+
+static
+int lttng_event_notifier_group_release(struct inode *inode, struct file *file)
+{
+ struct lttng_event_notifier_group *event_notifier_group =
+ file->private_data;
+
+ if (event_notifier_group)
+ lttng_event_notifier_group_destroy(event_notifier_group);
+ return 0;
+}
+
+static const struct file_operations lttng_event_notifier_group_fops = {
+ .owner = THIS_MODULE,
+ .release = lttng_event_notifier_group_release,
+ .unlocked_ioctl = lttng_event_notifier_group_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = lttng_event_notifier_group_ioctl,
+#endif
+};
+
/**
* lttng_channel_ioctl - lttng syscall through ioctl
*
long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct lttng_event *event;
- struct lttng_enabler *enabler;
+ struct lttng_event_enabler *event_enabler;
enum lttng_event_type *evtype = file->private_data;
switch (cmd) {
event = file->private_data;
return lttng_event_enable(event);
case LTTNG_TYPE_ENABLER:
- enabler = file->private_data;
- return lttng_enabler_enable(enabler);
+ event_enabler = file->private_data;
+ return lttng_event_enabler_enable(event_enabler);
default:
WARN_ON_ONCE(1);
return -ENOSYS;
event = file->private_data;
return lttng_event_disable(event);
case LTTNG_TYPE_ENABLER:
- enabler = file->private_data;
- return lttng_enabler_disable(enabler);
+ event_enabler = file->private_data;
+ return lttng_event_enabler_disable(event_enabler);
default:
WARN_ON_ONCE(1);
return -ENOSYS;
return -EINVAL;
case LTTNG_TYPE_ENABLER:
{
- enabler = file->private_data;
- return lttng_enabler_attach_bytecode(enabler,
+ event_enabler = file->private_data;
+ return lttng_event_enabler_attach_bytecode(event_enabler,
(struct lttng_kernel_filter_bytecode __user *) arg);
}
default:
int lttng_event_release(struct inode *inode, struct file *file)
{
struct lttng_event *event;
- struct lttng_enabler *enabler;
+ struct lttng_event_enabler *event_enabler;
enum lttng_event_type *evtype = file->private_data;
if (!evtype)
fput(event->chan->file);
break;
case LTTNG_TYPE_ENABLER:
- enabler = file->private_data;
- if (enabler)
- fput(enabler->chan->file);
+ event_enabler = file->private_data;
+ if (event_enabler)
+ fput(event_enabler->chan->file);
break;
default:
WARN_ON_ONCE(1);