X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=ltt-debugfs-abi.c;h=81afdbdbae28f13459fc84f9e3ed7dbe97137945;hb=1ec65de1d61ef4d4c6de6f9b2186167c9de1984e;hp=7fb7339205d5c99ff413d081ec50549606a526c6;hpb=1c25284c690cd38b71789c4024089d28de21caea;p=lttng-modules.git diff --git a/ltt-debugfs-abi.c b/ltt-debugfs-abi.c index 7fb73392..81afdbdb 100644 --- a/ltt-debugfs-abi.c +++ b/ltt-debugfs-abi.c @@ -20,6 +20,8 @@ * - Takes an instrumentation source as parameter * - e.g. tracepoints, dynamic_probes... * - Takes instrumentation source specific arguments. + * + * Dual LGPL v2.1/GPL v2 license. */ #include @@ -28,9 +30,12 @@ #include #include #include -#include +#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 @@ -41,8 +46,19 @@ static struct dentry *lttng_dentry; 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; +/* + * Teardown management: opened file descriptors keep a refcount on the module, + * so it can only exit when all file descriptors are closed. + */ + +enum channel_type { + PER_CPU_CHANNEL, + METADATA_CHANNEL, +}; + static int lttng_abi_create_session(void) { @@ -76,6 +92,101 @@ fd_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_VPID: + return lttng_add_vpid_to_ctx(ctx); + case LTTNG_KERNEL_CONTEXT_TID: + return lttng_add_tid_to_ctx(ctx); + case LTTNG_KERNEL_CONTEXT_VTID: + return lttng_add_vtid_to_ctx(ctx); + case LTTNG_KERNEL_CONTEXT_PPID: + return lttng_add_ppid_to_ctx(ctx); + case LTTNG_KERNEL_CONTEXT_VPPID: + return lttng_add_vppid_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 * @@ -84,8 +195,14 @@ fd_error: * @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 + * LTTNG_KERNEL_WAIT_QUIESCENT + * Returns after all previously running probes have completed * * The returned session will be deleted when its file descriptor is closed. */ @@ -93,27 +210,84 @@ static 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(); + case LTTNG_KERNEL_WAIT_QUIESCENT: + synchronize_trace(); + return 0; + case LTTNG_KERNEL_CALIBRATE: + { + struct lttng_kernel_calibrate __user *ucalibrate = + (struct lttng_kernel_calibrate __user *) arg; + struct lttng_kernel_calibrate calibrate; + int ret; + + if (copy_from_user(&calibrate, ucalibrate, sizeof(calibrate))) + return -EFAULT; + ret = lttng_calibrate(&calibrate); + if (copy_to_user(ucalibrate, &calibrate, sizeof(calibrate))) + return -EFAULT; + return ret; + } default: return -ENOIOCTLCMD; } } static const struct file_operations lttng_fops = { + .owner = THIS_MODULE, .unlocked_ioctl = lttng_ioctl, #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; + + /* + * 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) { + goto create_error; + } + return; + +create_error: + WARN_ON(1); + return; /* not allowed to return error */ +} + +static int lttng_abi_create_channel(struct file *session_file, - struct lttng_channel __user *uchan_param) + struct lttng_kernel_channel __user *uchan_param, + enum channel_type channel_type) { struct ltt_session *session = session_file->private_data; + const struct file_operations *fops = NULL; + const char *transport_name; struct ltt_channel *chan; struct file *chan_file; - struct lttng_channel chan_param; + struct lttng_kernel_channel chan_param; int chan_fd; int ret = 0; @@ -124,31 +298,69 @@ int lttng_abi_create_channel(struct file *session_file, ret = chan_fd; goto fd_error; } + switch (channel_type) { + case PER_CPU_CHANNEL: + fops = <tng_channel_fops; + break; + case METADATA_CHANNEL: + fops = <tng_metadata_fops; + break; + } + chan_file = anon_inode_getfile("[lttng_channel]", - <tng_channel_fops, + fops, NULL, O_RDWR); if (IS_ERR(chan_file)) { ret = PTR_ERR(chan_file); goto file_error; } + switch (channel_type) { + case PER_CPU_CHANNEL: + if (chan_param.output == LTTNG_KERNEL_SPLICE) { + transport_name = chan_param.overwrite ? + "relay-overwrite" : "relay-discard"; + } else if (chan_param.output == LTTNG_KERNEL_MMAP) { + transport_name = chan_param.overwrite ? + "relay-overwrite-mmap" : "relay-discard-mmap"; + } else { + return -EINVAL; + } + break; + case METADATA_CHANNEL: + if (chan_param.output == LTTNG_KERNEL_SPLICE) + transport_name = "relay-metadata"; + else if (chan_param.output == LTTNG_KERNEL_MMAP) + transport_name = "relay-metadata-mmap"; + else + return -EINVAL; + break; + default: + transport_name = ""; + 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 = 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; } 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_file->f_count); + atomic_long_inc(&session_file->f_count); return chan_fd; @@ -168,8 +380,14 @@ fd_error: * @arg: command arg * * This ioctl implements lttng commands: - * LTTNG_CHANNEL + * LTTNG_KERNEL_CHANNEL * Returns a LTTng channel file descriptor + * LTTNG_KERNEL_ENABLE + * Enables tracing for a session (weak enable) + * LTTNG_KERNEL_DISABLE + * Disables tracing for a session (strong disable) + * LTTNG_KERNEL_METADATA + * Returns a LTTng metadata file descriptor * * The returned channel will be deleted when its file descriptor is closed. */ @@ -179,12 +397,20 @@ 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(file, (struct lttng_channel __user *)arg); - case LTTNG_SESSION_START: - return ltt_session_start(session); - case LTTNG_SESSION_STOP: - return ltt_session_stop(session); + case LTTNG_KERNEL_CHANNEL: + return lttng_abi_create_channel(file, + (struct lttng_kernel_channel __user *) arg, + PER_CPU_CHANNEL); + case LTTNG_KERNEL_SESSION_START: + case LTTNG_KERNEL_ENABLE: + return ltt_session_enable(session); + case LTTNG_KERNEL_SESSION_STOP: + case LTTNG_KERNEL_DISABLE: + return ltt_session_disable(session); + case LTTNG_KERNEL_METADATA: + return lttng_abi_create_channel(file, + (struct lttng_kernel_channel __user *) arg, + METADATA_CHANNEL); default: return -ENOIOCTLCMD; } @@ -202,11 +428,14 @@ static int lttng_session_release(struct inode *inode, struct file *file) { struct ltt_session *session = file->private_data; - ltt_session_destroy(session); + + if (session) + ltt_session_destroy(session); return 0; } static const struct file_operations lttng_session_fops = { + .owner = THIS_MODULE, .release = lttng_session_release, .unlocked_ioctl = lttng_session_ioctl, #ifdef CONFIG_COMPAT @@ -238,9 +467,18 @@ int lttng_abi_open_stream(struct file *channel_file) ret = PTR_ERR(stream_file); goto file_error; } + /* + * 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 on the channel */ - atomic_inc(&channel_file->f_count); + /* + * 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: @@ -252,52 +490,65 @@ fd_error: static int lttng_abi_create_event(struct file *channel_file, - struct lttng_event __user *uevent_param) + struct lttng_kernel_event __user *uevent_param) { 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_name[PATH_MAX - 1] = '\0'; - event_fd = get_unused_fd(); - if (event_fd < 0) { - ret = event_fd; - goto fd_error; - } - event_file = anon_inode_getfile("[lttng_event]", - <tng_event_fops, - NULL, O_RDWR); - if (IS_ERR(event_file)) { - ret = PTR_ERR(event_file); - goto file_error; + event_param.name[LTTNG_SYM_NAME_LEN - 1] = '\0'; + switch (event_param.instrumentation) { + case LTTNG_KERNEL_KRETPROBE: + event_param.u.kretprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0'; + break; + 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; } - /* - * We tolerate no failure path after event creation. It will stay - * invariant for the rest of the session. - */ - event = ltt_event_create(channel, event_name, event_param.itype, - NULL, NULL); /* TODO non-null probe */ - if (!event) { - goto event_error; - ret = -EEXIST; + switch (event_param.instrumentation) { + default: + event_fd = get_unused_fd(); + if (event_fd < 0) { + ret = event_fd; + goto fd_error; + } + event_file = anon_inode_getfile("[lttng_event]", + <tng_event_fops, + NULL, O_RDWR); + 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, NULL); + if (!event) { + ret = -EINVAL; + goto event_error; + } + event_file->private_data = event; + fd_install(event_fd, event_file); + /* The event holds a reference on the channel */ + atomic_long_inc(&channel_file->f_count); + break; + case LTTNG_KERNEL_SYSCALLS: + ret = lttng_syscalls_register(channel, NULL); + if (ret) + goto fd_error; + event_fd = 0; + break; } - event_file->private_data = event; - fd_install(event_fd, event_file); - /* The event holds a reference on the channel */ - atomic_inc(&channel_file->f_count); - kfree(event_name); return event_fd; event_error: @@ -305,8 +556,6 @@ event_error: file_error: put_unused_fd(event_fd); fd_error: -name_error: - kfree(event_name); return ret; } @@ -318,30 +567,67 @@ name_error: * @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 + * LTTNG_KERNEL_ENABLE + * Enable recording for events in this channel (weak enable) + * LTTNG_KERNEL_DISABLE + * Disable recording for events in this channel (strong disable) * - * 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 *file, unsigned int cmd, unsigned long arg) { + struct ltt_channel *channel = file->private_data; + switch (cmd) { - case LTTNG_STREAM: + 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); + case LTTNG_KERNEL_ENABLE: + return ltt_channel_enable(channel); + case LTTNG_KERNEL_DISABLE: + return ltt_channel_disable(channel); + 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. + * + * Channel and event file descriptors also hold a reference on the session. + */ +static +long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + switch (cmd) { + case LTTNG_KERNEL_STREAM: return lttng_abi_open_stream(file); - case LTTNG_EVENT: - return lttng_abi_create_event(file, (struct lttng_event __user *)arg); default: return -ENOIOCTLCMD; } } -/* TODO: poll */ -#if 0 /** * lttng_channel_poll - lttng stream addition/removal monitoring * @@ -355,58 +641,111 @@ unsigned int lttng_channel_poll(struct file *file, poll_table *wait) if (file->f_mode & FMODE_READ) { poll_wait_set_exclusive(wait); - poll_wait(file, &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 + if (channel->ops->buffer_has_read_closed_stream(channel->chan)) return POLLIN | POLLRDNORM; + return 0; } return mask; } -#endif //0 static 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; } static const struct file_operations lttng_channel_fops = { + .owner = THIS_MODULE, .release = lttng_channel_release, -/* TODO */ -#if 0 .poll = lttng_channel_poll, -#endif //0 .unlocked_ioctl = lttng_channel_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = lttng_channel_ioctl, #endif }; +static const struct file_operations lttng_metadata_fops = { + .owner = THIS_MODULE, + .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_CONTEXT + * Prepend a context field to each record of this event + * LTTNG_KERNEL_ENABLE + * Enable recording for this event (weak enable) + * LTTNG_KERNEL_DISABLE + * Disable recording for this event (strong disable) + */ +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); + case LTTNG_KERNEL_ENABLE: + return ltt_event_enable(event); + case LTTNG_KERNEL_DISABLE: + return ltt_event_disable(event); + 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 = { + .owner = THIS_MODULE, .release = lttng_event_release, + .unlocked_ioctl = lttng_event_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = lttng_event_ioctl, +#endif }; int __init ltt_debugfs_abi_init(void) { int ret = 0; + wrapper_vmalloc_sync_all(); lttng_dentry = debugfs_create_file("lttng", S_IWUSR, NULL, NULL, - <tng_session_fops); + <tng_fops); if (IS_ERR(lttng_dentry) || !lttng_dentry) { printk(KERN_ERR "Error creating LTTng control file\n"); ret = -ENOMEM;