diff options
| -rw-r--r-- | fs/Makefile | 1 | ||||
| -rw-r--r-- | fs/tracefs/Makefile | 4 | ||||
| -rw-r--r-- | fs/tracefs/inode.c | 650 | ||||
| -rw-r--r-- | include/linux/tracefs.h | 45 | ||||
| -rw-r--r-- | include/uapi/linux/magic.h | 2 | ||||
| -rw-r--r-- | kernel/trace/ftrace.c | 22 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 187 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_events.c | 32 | ||||
| -rw-r--r-- | kernel/trace/trace_functions_graph.c | 7 | ||||
| -rw-r--r-- | kernel/trace/trace_kprobe.c | 10 | ||||
| -rw-r--r-- | kernel/trace/trace_probe.h | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_stat.c | 10 |
13 files changed, 832 insertions, 142 deletions
diff --git a/fs/Makefile b/fs/Makefile index a88ac4838c9e..cb92fd4c3172 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -118,6 +118,7 @@ obj-$(CONFIG_HOSTFS) += hostfs/ obj-$(CONFIG_HPPFS) += hppfs/ obj-$(CONFIG_CACHEFILES) += cachefiles/ obj-$(CONFIG_DEBUG_FS) += debugfs/ +obj-$(CONFIG_TRACING) += tracefs/ obj-$(CONFIG_OCFS2_FS) += ocfs2/ obj-$(CONFIG_BTRFS_FS) += btrfs/ obj-$(CONFIG_GFS2_FS) += gfs2/ diff --git a/fs/tracefs/Makefile b/fs/tracefs/Makefile new file mode 100644 index 000000000000..82fa35b656c4 --- /dev/null +++ b/fs/tracefs/Makefile @@ -0,0 +1,4 @@ +tracefs-objs := inode.o + +obj-$(CONFIG_TRACING) += tracefs.o + diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c new file mode 100644 index 000000000000..d92bdf3b079a --- /dev/null +++ b/fs/tracefs/inode.c @@ -0,0 +1,650 @@ +/* + * inode.c - part of tracefs, a pseudo file system for activating tracing + * + * Based on debugfs by: Greg Kroah-Hartman <greg@kroah.com> + * + * Copyright (C) 2014 Red Hat Inc, author: Steven Rostedt <srostedt@redhat.com> + * + * 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. + * + * tracefs is the file system that is used by the tracing infrastructure. + * + */ + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/mount.h> +#include <linux/kobject.h> +#include <linux/namei.h> +#include <linux/tracefs.h> +#include <linux/fsnotify.h> +#include <linux/seq_file.h> +#include <linux/parser.h> +#include <linux/magic.h> +#include <linux/slab.h> + +#define TRACEFS_DEFAULT_MODE 0700 + +static struct vfsmount *tracefs_mount; +static int tracefs_mount_count; +static bool tracefs_registered; + +static ssize_t default_read_file(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + return 0; +} + +static ssize_t default_write_file(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + return count; +} + +static const struct file_operations tracefs_file_operations = { + .read = default_read_file, + .write = default_write_file, + .open = simple_open, + .llseek = noop_llseek, +}; + +static struct tracefs_dir_ops { + int (*mkdir)(const char *name); + int (*rmdir)(const char *name); +} tracefs_ops; + +static char *get_dname(struct dentry *dentry) +{ + const char *dname; + char *name; + int len = dentry->d_name.len; + + dname = dentry->d_name.name; + name = kmalloc(len + 1, GFP_KERNEL); + if (!name) + return NULL; + memcpy(name, dname, len); + name[len] = 0; + return name; +} + +static int tracefs_syscall_mkdir(struct inode *inode, struct dentry *dentry, umode_t mode) +{ + char *name; + int ret; + + name = get_dname(dentry); + if (!name) + return -ENOMEM; + + /* + * The mkdir call can call the generic functions that create + * the files within the tracefs system. It is up to the individual + * mkdir routine to handle races. + */ + mutex_unlock(&inode->i_mutex); + ret = tracefs_ops.mkdir(name); + mutex_lock(&inode->i_mutex); + + kfree(name); + + return ret; +} + +static int tracefs_syscall_rmdir(struct inode *inode, struct dentry *dentry) +{ + char *name; + int ret; + + name = get_dname(dentry); + if (!name) + return -ENOMEM; + + /* + * The rmdir call can call the generic functions that create + * the files within the tracefs system. It is up to the individual + * rmdir routine to handle races. + * This time we need to unlock not only the parent (inode) but + * also the directory that is being deleted. + */ + mutex_unlock(&inode->i_mutex); + mutex_unlock(&dentry->d_inode->i_mutex); + + ret = tracefs_ops.rmdir(name); + + mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); + mutex_lock(&dentry->d_inode->i_mutex); + + kfree(name); + + return ret; +} + +static const struct inode_operations tracefs_dir_inode_operations = { + .lookup = simple_lookup, + .mkdir = tracefs_syscall_mkdir, + .rmdir = tracefs_syscall_rmdir, +}; + +static struct inode *tracefs_get_inode(struct super_block *sb) +{ + struct inode *inode = new_inode(sb); + if (inode) { + inode->i_ino = get_next_ino(); + inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; + } + return inode; +} + +struct tracefs_mount_opts { + kuid_t uid; + kgid_t gid; + umode_t mode; +}; + +enum { + Opt_uid, + Opt_gid, + Opt_mode, + Opt_err +}; + +static const match_table_t tokens = { + {Opt_uid, "uid=%u"}, + {Opt_gid, "gid=%u"}, + {Opt_mode, "mode=%o"}, + {Opt_err, NULL} +}; + +struct tracefs_fs_info { + struct tracefs_mount_opts mount_opts; +}; + +static int tracefs_parse_options(char *data, struct tracefs_mount_opts *opts) +{ + substring_t args[MAX_OPT_ARGS]; + int option; + int token; + kuid_t uid; + kgid_t gid; + char *p; + + opts->mode = TRACEFS_DEFAULT_MODE; + + while ((p = strsep(&data, ",")) != NULL) { + if (!*p) + continue; + + token = match_token(p, tokens, args); + switch (token) { + case Opt_uid: + if (match_int(&args[0], &option)) + return -EINVAL; + uid = make_kuid(current_user_ns(), option); + if (!uid_valid(uid)) + return -EINVAL; + opts->uid = uid; + break; + case Opt_gid: + if (match_int(&args[0], &option)) + return -EINVAL; + gid = make_kgid(current_user_ns(), option); + if (!gid_valid(gid)) + return -EINVAL; + opts->gid = gid; + break; + case Opt_mode: + if (match_octal(&args[0], &option)) + return -EINVAL; + opts->mode = option & S_IALLUGO; + break; + /* + * We might like to report bad mount options here; + * but traditionally tracefs has ignored all mount options + */ + } + } + + return 0; +} + +static int tracefs_apply_options(struct super_block *sb) +{ + struct tracefs_fs_info *fsi = sb->s_fs_info; + struct inode *inode = sb->s_root->d_inode; + struct tracefs_mount_opts *opts = &fsi->mount_opts; + + inode->i_mode &= ~S_IALLUGO; + inode->i_mode |= opts->mode; + + inode->i_uid = opts->uid; + inode->i_gid = opts->gid; + + return 0; +} + +static int tracefs_remount(struct super_block *sb, int *flags, char *data) +{ + int err; + struct tracefs_fs_info *fsi = sb->s_fs_info; + + sync_filesystem(sb); + err = tracefs_parse_options(data, &fsi->mount_opts); + if (err) + goto fail; + + tracefs_apply_options(sb); + +fail: + return err; +} + +static int tracefs_show_options(struct seq_file *m, struct dentry *root) +{ + struct tracefs_fs_info *fsi = root->d_sb->s_fs_info; + struct tracefs_mount_opts *opts = &fsi->mount_opts; + + if (!uid_eq(opts->uid, GLOBAL_ROOT_UID)) + seq_printf(m, ",uid=%u", + from_kuid_munged(&init_user_ns, opts->uid)); + if (!gid_eq(opts->gid, GLOBAL_ROOT_GID)) + seq_printf(m, ",gid=%u", + from_kgid_munged(&init_user_ns, opts->gid)); + if (opts->mode != TRACEFS_DEFAULT_MODE) + seq_printf(m, ",mode=%o", opts->mode); + + return 0; +} + +static const struct super_operations tracefs_super_operations = { + .statfs = simple_statfs, + .remount_fs = tracefs_remount, + .show_options = tracefs_show_options, +}; + +static int trace_fill_super(struct super_block *sb, void *data, int silent) +{ + static struct tree_descr trace_files[] = {{""}}; + struct tracefs_fs_info *fsi; + int err; + + save_mount_options(sb, data); + + fsi = kzalloc(sizeof(struct tracefs_fs_info), GFP_KERNEL); + sb->s_fs_info = fsi; + if (!fsi) { + err = -ENOMEM; + goto fail; + } + + err = tracefs_parse_options(data, &fsi->mount_opts); + if (err) + goto fail; + + err = simple_fill_super(sb, TRACEFS_MAGIC, trace_files); + if (err) + goto fail; + + sb->s_op = &tracefs_super_operations; + + tracefs_apply_options(sb); + + return 0; + +fail: + kfree(fsi); + sb->s_fs_info = NULL; + return err; +} + +static struct dentry *trace_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, + void *data) +{ + return mount_single(fs_type, flags, data, trace_fill_super); +} + +static struct file_system_type trace_fs_type = { + .owner = THIS_MODULE, + .name = "tracefs", + .mount = trace_mount, + .kill_sb = kill_litter_super, +}; +MODULE_ALIAS_FS("tracefs"); + +static struct dentry *start_creating(const char *name, struct dentry *parent) +{ + struct dentry *dentry; + int error; + + pr_debug("tracefs: creating file '%s'\n",name); + + error = simple_pin_fs(&trace_fs_type, &tracefs_mount, + &tracefs_mount_count); + if (error) + return ERR_PTR(error); + + /* If the parent is not specified, we create it in the root. + * We need the root dentry to do this, which is in the super + * block. A pointer to that is in the struct vfsmount that we + * have around. + */ + if (!parent) + parent = tracefs_mount->mnt_root; + + mutex_lock(&parent->d_inode->i_mutex); + dentry = lookup_one_len(name, parent, strlen(name)); + if (!IS_ERR(dentry) && dentry->d_inode) { + dput(dentry); + dentry = ERR_PTR(-EEXIST); + } + if (IS_ERR(dentry)) + mutex_unlock(&parent->d_inode->i_mutex); + return dentry; +} + +static struct dentry *failed_creating(struct dentry *dentry) +{ + mutex_unlock(&dentry->d_parent->d_inode->i_mutex); + dput(dentry); + simple_release_fs(&tracefs_mount, &tracefs_mount_count); + return NULL; +} + +static struct dentry *end_creating(struct dentry *dentry) +{ + mutex_unlock(&dentry->d_parent->d_inode->i_mutex); + return dentry; +} + +/** + * tracefs_create_file - create a file in the tracefs filesystem + * @name: a pointer to a string containing the name of the file to create. + * @mode: the permission that the file should have. + * @parent: a pointer to the parent dentry for this file. This should be a + * directory dentry if set. If this parameter is NULL, then the + * file will be created in the root of the tracefs filesystem. + * @data: a pointer to something that the caller will want to get to later + * on. The inode.i_private pointer will point to this value on + * the open() call. + * @fops: a pointer to a struct file_operations that should be used for + * this file. + * + * This is the basic "create a file" function for tracefs. It allows for a + * wide range of flexibility in creating a file, or a directory (if you want + * to create a directory, the tracefs_create_dir() function is + * recommended to be used instead.) + * + * This function will return a pointer to a dentry if it succeeds. This + * pointer must be passed to the tracefs_remove() function when the file is + * to be removed (no automatic cleanup happens if your module is unloaded, + * you are responsible here.) If an error occurs, %NULL will be returned. + * + * If tracefs is not enabled in the kernel, the value -%ENODEV will be + * returned. + */ +struct dentry *tracefs_create_file(const char *name, umode_t mode, + struct dentry *parent, void *data, + const struct file_operations *fops) +{ + struct dentry *dentry; + struct inode *inode; + + if (!(mode & S_IFMT)) + mode |= S_IFREG; + BUG_ON(!S_ISREG(mode)); + dentry = start_creating(name, parent); + + if (IS_ERR(dentry)) + return NULL; + + inode = tracefs_get_inode(dentry->d_sb); + if (unlikely(!inode)) + return failed_creating(dentry); + + inode->i_mode = mode; + inode->i_fop = fops ? fops : &tracefs_file_operations; + inode->i_private = data; + d_instantiate(dentry, inode); + fsnotify_create(dentry->d_parent->d_inode, dentry); + return end_creating(dentry); +} + +static struct dentry *__create_dir(const char *name, struct dentry *parent, + const struct inode_operations *ops) +{ + struct dentry *dentry = start_creating(name, parent); + struct inode *inode; + + if (IS_ERR(dentry)) + return NULL; + + inode = tracefs_get_inode(dentry->d_sb); + if (unlikely(!inode)) + return failed_creating(dentry); + + inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; + inode->i_op = ops; + inode->i_fop = &simple_dir_operations; + + /* directory inodes start off with i_nlink == 2 (for "." entry) */ + inc_nlink(inode); + d_instantiate(dentry, inode); + inc_nlink(dentry->d_parent->d_inode); + fsnotify_mkdir(dentry->d_parent->d_inode, dentry); + return end_creating(dentry); +} + +/** + * tracefs_create_dir - create a directory in the tracefs filesystem + * @name: a pointer to a string containing the name of the directory to + * create. + * @parent: a pointer to the parent dentry for this file. This should be a + * directory dentry if set. If this parameter is NULL, then the + * directory will be created in the root of the tracefs filesystem. + * + * This function creates a directory in tracefs with the given name. + * + * This function will return a pointer to a dentry if it succeeds. This + * pointer must be passed to the tracefs_remove() function when the file is + * to be removed. If an error occurs, %NULL will be returned. + * + * If tracing is not enabled in the kernel, the value -%ENODEV will be + * returned. + */ +struct dentry *tracefs_create_dir(const char *name, struct dentry *parent) +{ + return __create_dir(name, parent, &simple_dir_inode_operations); +} + +/** + * tracefs_create_instance_dir - create the tracing instances directory + * @name: The name of the instances directory to create + * @parent: The parent directory that the instances directory will exist + * @mkdir: The function to call when a mkdir is performed. + * @rmdir: The function to call when a rmdir is performed. + * + * Only one instances directory is allowed. + * + * The instances directory is special as it allows for mkdir and rmdir to + * to be done by userspace. When a mkdir or rmdir is performed, the inode + * locks are released and the methhods passed in (@mkdir and @rmdir) are + * called without locks and with the name of the directory being created + * within the instances directory. + * + * Returns the dentry of the instances directory. + */ +struct dentry *tracefs_create_instance_dir(const char *name, struct dentry *parent, + int (*mkdir)(const char *name), + int (*rmdir)(const char *name)) +{ + struct dentry *dentry; + + /* Only allow one instance of the instances directory. */ + if (WARN_ON(tracefs_ops.mkdir || tracefs_ops.rmdir)) + return NULL; + + dentry = __create_dir(name, parent, &tracefs_dir_inode_operations); + if (!dentry) + return NULL; + + tracefs_ops.mkdir = mkdir; + tracefs_ops.rmdir = rmdir; + + return dentry; +} + +static inline int tracefs_positive(struct dentry *dentry) +{ + return dentry->d_inode && !d_unhashed(dentry); +} + +static int __tracefs_remove(struct dentry *dentry, struct dentry *parent) +{ + int ret = 0; + + if (tracefs_positive(dentry)) { + if (dentry->d_inode) { + dget(dentry); + switch (dentry->d_inode->i_mode & S_IFMT) { + case S_IFDIR: + ret = simple_rmdir(parent->d_inode, dentry); + break; + default: + simple_unlink(parent->d_inode, dentry); + break; + } + if (!ret) + d_delete(dentry); + dput(dentry); + } + } + return ret; +} + +/** + * tracefs_remove - removes a file or directory from the tracefs filesystem + * @dentry: a pointer to a the dentry of the file or directory to be + * removed. + * + * This function removes a file or directory in tracefs that was previously + * created with a call to another tracefs function (like + * tracefs_create_file() or variants thereof.) + */ +void tracefs_remove(struct dentry *dentry) +{ + struct dentry *parent; + int ret; + + if (IS_ERR_OR_NULL(dentry)) + return; + + parent = dentry->d_parent; + if (!parent || !parent->d_inode) + return; + + mutex_lock(&parent->d_inode->i_mutex); + ret = __tracefs_remove(dentry, parent); + mutex_unlock(&parent->d_inode->i_mutex); + if (!ret) + simple_release_fs(&tracefs_mount, &tracefs_mount_count); +} + +/** + * tracefs_remove_recursive - recursively removes a directory + * @dentry: a pointer to a the dentry of the directory to be removed. + * + * This function recursively removes a directory tree in tracefs that + * was previously created with a call to another tracefs function + * (like tracefs_create_file() or variants thereof.) + */ +void tracefs_remove_recursive(struct dentry *dentry) +{ + struct dentry *child, *parent; + + if (IS_ERR_OR_NULL(dentry)) + return; + + parent = dentry->d_parent; + if (!parent || !parent->d_inode) + return; + + parent = dentry; + down: + mutex_lock(&parent->d_inode->i_mutex); + loop: + /* + * The parent->d_subdirs is protected by the d_lock. Outside that + * lock, the child can be unlinked and set to be freed which can + * use the d_u.d_child as the rcu head and corrupt this list. + */ + spin_lock(&parent->d_lock); + list_for_each_entry(child, &parent->d_subdirs, d_child) { + if (!tracefs_positive(child)) + continue; + + /* perhaps simple_empty(child) makes more sense */ + if (!list_empty(&child->d_subdirs)) { + spin_unlock(&parent->d_lock); + mutex_unlock(&parent->d_inode->i_mutex); + parent = child; + goto down; + } + + spin_unlock(&parent->d_lock); + + if (!__tracefs_remove(child, parent)) + simple_release_fs(&tracefs_mount, &tracefs_mount_count); + + /* + * The parent->d_lock protects agaist child from unlinking + * from d_subdirs. When releasing the parent->d_lock we can + * no longer trust that the next pointer is valid. + * Restart the loop. We'll skip this one with the + * tracefs_positive() check. + */ + goto loop; + } + spin_unlock(&parent->d_lock); + + mutex_unlock(&parent->d_inode->i_mutex); + child = parent; + parent = parent->d_parent; + mutex_lock(&parent->d_inode->i_mutex); + + if (child != dentry) + /* go up */ + goto loop; + + if (!__tracefs_remove(child, parent)) + simple_release_fs(&tracefs_mount, &tracefs_mount_count); + mutex_unlock(&parent->d_inode->i_mutex); +} + +/** + * tracefs_initialized - Tells whether tracefs has been registered + */ +bool tracefs_initialized(void) +{ + return tracefs_registered; +} + +static struct kobject *trace_kobj; + +static int __init tracefs_init(void) +{ + int retval; + + trace_kobj = kobject_create_and_add("tracing", kernel_kobj); + if (!trace_kobj) + return -EINVAL; + + retval = register_filesystem(&trace_fs_type); + if (!retval) + tracefs_registered = true; + + return retval; +} +core_initcall(tracefs_init); diff --git a/include/linux/tracefs.h b/include/linux/tracefs.h new file mode 100644 index 000000000000..5b727a17beee --- /dev/null +++ b/include/linux/tracefs.h @@ -0,0 +1,45 @@ +/* + * tracefs.h - a pseudo file system for activating tracing + * + * Based on debugfs by: 2004 Greg Kroah-Hartman <greg@kroah.com> + * + * Copyright (C) 2014 Red Hat Inc, author: Steven Rostedt <srostedt@redhat.com> + * + * 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. + * + * tracefs is the file system that is used by the tracing infrastructure. + * + */ + +#ifndef _TRACEFS_H_ +#define _TRACEFS_H_ + +#include <linux/fs.h> +#include <linux/seq_file.h> + +#include <linux/types.h> + +struct file_operations; + +#ifdef CONFIG_TRACING + +struct dentry *tracefs_create_file(const char *name, umode_t mode, + struct dentry *parent, void *data, + const struct file_operations *fops); + +struct dentry *tracefs_create_dir(const char *name, struct dentry *parent); + +void tracefs_remove(struct dentry *dentry); +void tracefs_remove_recursive(struct dentry *dentry); + +struct dentry *tracefs_create_instance_dir(const char *name, struct dentry *parent, + int (*mkdir)(const char *name), + int (*rmdir)(const char *name)); + +bool tracefs_initialized(void); + +#endif /* CONFIG_TRACING */ + +#endif diff --git a/include/uapi/linux/magic.h b/include/uapi/linux/magic.h index 7d664ea85ebd..7b1425a6b370 100644 --- a/include/uapi/linux/magic.h +++ b/include/uapi/linux/magic.h @@ -58,6 +58,8 @@ #define STACK_END_MAGIC 0x57AC6E9D +#define TRACEFS_MAGIC 0x74726163 + #define V9FS_MAGIC 0x01021997 #define BDEVFS_MAGIC 0x62646576 diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 4f228024055b..5a2e0b53af30 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -18,7 +18,7 @@ #include <linux/kallsyms.h> #include <linux/seq_file.h> #include <linux/suspend.h> -#include <linux/debugfs.h> +#include <linux/tracefs.h> #include <linux/hardirq.h> #include <linux/kthread.h> #include <linux/uaccess.h> @@ -1008,7 +1008,7 @@ static struct tracer_stat function_stats __initdata = { .stat_show = function_stat_show }; -static __init void ftrace_profile_debugfs(struct dentry *d_tracer) +static __init void ftrace_profile_tracefs(struct dentry *d_tracer) { struct ftrace_profile_stat *stat; struct dentry *entry; @@ -1044,15 +1044,15 @@ static __init void ftrace_profile_debugfs(struct dentry *d_tracer) } } - entry = debugfs_create_file("function_profile_enabled", 0644, + entry = tracefs_create_file("function_profile_enabled", 0644, d_tracer, NULL, &ftrace_profile_fops); if (!entry) - pr_warning("Could not create debugfs " + pr_warning("Could not create tracefs " "'function_profile_enabled' entry\n"); } #else /* CONFIG_FUNCTION_PROFILER */ -static __init void ftrace_profile_debugfs(struct dentry *d_tracer) +static __init void ftrace_profile_tracefs(struct dentry *d_tracer) { } #endif /* CONFIG_FUNCTION_PROFILER */ @@ -4712,7 +4712,7 @@ void ftrace_destroy_filter_files(struct ftrace_ops *ops) mutex_unlock(&ftrace_lock); } -static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) +static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { trace_create_file("available_filter_functions", 0444, @@ -5020,7 +5020,7 @@ static int __init ftrace_nodyn_init(void) } core_initcall(ftrace_nodyn_init); -static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; } +static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; } static inline void ftrace_startup_enable(int command) { } static inline void ftrace_startup_all(int command) { } /* Keep as macros so we do not need to define the commands */ @@ -5473,7 +5473,7 @@ static const struct file_operations ftrace_pid_fops = { .release = ftrace_pid_release, }; -static __init int ftrace_init_debugfs(void) +static __init int ftrace_init_tracefs(void) { struct dentry *d_tracer; @@ -5481,16 +5481,16 @@ static __init int ftrace_init_debugfs(void) if (IS_ERR(d_tracer)) return 0; - ftrace_init_dyn_debugfs(d_tracer); + ftrace_init_dyn_tracefs(d_tracer); trace_create_file("set_ftrace_pid", 0644, d_tracer, NULL, &ftrace_pid_fops); - ftrace_profile_debugfs(d_tracer); + ftrace_profile_tracefs(d_tracer); return 0; } -fs_initcall(ftrace_init_debugfs); +fs_initcall(ftrace_init_tracefs); /** * ftrace_kill - kill ftrace diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 62c6506d663f..bcfa2add6dda 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -20,6 +20,7 @@ #include <linux/notifier.h> #include <linux/irqflags.h> #include <linux/debugfs.h> +#include <linux/tracefs.h> #include <linux/pagemap.h> #include <linux/hardirq.h> #include <linux/linkage.h> @@ -31,6 +32,7 @@ #include <linux/splice.h> #include <linux/kdebug.h> #include <linux/string.h> +#include <linux/mount.h> #include <linux/rwsem.h> #include <linux/slab.h> #include <linux/ctype.h> @@ -4105,9 +4107,24 @@ static void tracing_set_nop(struct trace_array *tr) tr->current_trace = &nop_trace; } -static int tracing_set_tracer(struct trace_array *tr, const char *buf) +static void update_tracer_options(struct trace_array *tr, struct tracer *t) { static struct trace_option_dentry *topts; + + /* Only enable if the directory has been created already. */ + if (!tr->dir) + return; + + /* Currently, only the top instance has options */ + if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) + return; + + destroy_trace_option_files(topts); + topts = create_trace_option_files(tr, t); +} + +static int tracing_set_tracer(struct trace_array *tr, const char *buf) +{ struct tracer *t; #ifdef CONFIG_TRACER_MAX_TRACE bool had_max_tr; @@ -4172,11 +4189,7 @@ static int tracing_set_tracer(struct trace_array *tr, const char *buf) free_snapshot(tr); } #endif - /* Currently, only the top instance has options */ - if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { - destroy_trace_option_files(topts); - topts = create_trace_option_files(tr, t); - } + update_tracer_options(tr, t); #ifdef CONFIG_TRACER_MAX_TRACE if (t->use_max_tr && !had_max_tr) { @@ -5817,6 +5830,14 @@ static inline __init int register_snapshot_cmd(void) { return 0; } static struct dentry *tracing_get_dentry(struct trace_array *tr) { + if (WARN_ON(!tr->dir)) + return ERR_PTR(-ENODEV); + + /* Top directory uses NULL as the parent */ + if (tr->flags & TRACE_ARRAY_FL_GLOBAL) + return NULL; + + /* All sub buffers have a descriptor */ return tr->dir; } @@ -5831,10 +5852,10 @@ static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) if (IS_ERR(d_tracer)) return NULL; - tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); + tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); WARN_ONCE(!tr->percpu_dir, - "Could not create debugfs directory 'per_cpu/%d'\n", cpu); + "Could not create tracefs directory 'per_cpu/%d'\n", cpu); return tr->percpu_dir; } @@ -5851,7 +5872,7 @@ trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, } static void -tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) +tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) { struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); struct dentry *d_cpu; @@ -5861,9 +5882,9 @@ tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) return; snprintf(cpu_dir, 30, "cpu%ld", cpu); - d_cpu = debugfs_create_dir(cpu_dir, d_percpu); + d_cpu = tracefs_create_dir(cpu_dir, d_percpu); if (!d_cpu) { - pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); + pr_warning("Could not create tracefs '%s' entry\n", cpu_dir); return; } @@ -6015,9 +6036,9 @@ struct dentry *trace_create_file(const char *name, { struct dentry *ret; - ret = debugfs_create_file(name, mode, parent, data, fops); + ret = tracefs_create_file(name, mode, parent, data, fops); if (!ret) - pr_warning("Could not create debugfs '%s' entry\n", name); + pr_warning("Could not create tracefs '%s' entry\n", name); return ret; } @@ -6034,9 +6055,9 @@ static struct dentry *trace_options_init_dentry(struct trace_array *tr) if (IS_ERR(d_tracer)) return NULL; - tr->options = debugfs_create_dir("options", d_tracer); + tr->options = tracefs_create_dir("options", d_tracer); if (!tr->options) { - pr_warning("Could not create debugfs directory 'options'\n"); + pr_warning("Could not create tracefs directory 'options'\n"); return NULL; } @@ -6105,7 +6126,7 @@ destroy_trace_option_files(struct trace_option_dentry *topts) return; for (cnt = 0; topts[cnt].opt; cnt++) - debugfs_remove(topts[cnt].entry); + tracefs_remove(topts[cnt].entry); kfree(topts); } @@ -6194,7 +6215,7 @@ static const struct file_operations rb_simple_fops = { struct dentry *trace_instance_dir; static void -init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); +init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); static int allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) @@ -6271,7 +6292,7 @@ static void free_trace_buffers(struct trace_array *tr) #endif } -static int new_instance_create(const char *name) +static int instance_mkdir(const char *name) { struct trace_array *tr; int ret; @@ -6310,17 +6331,17 @@ static int new_instance_create(const char *name) if (allocate_trace_buffers(tr, trace_buf_size) < 0) goto out_free_tr; - tr->dir = debugfs_create_dir(name, trace_instance_dir); + tr->dir = tracefs_create_dir(name, trace_instance_dir); if (!tr->dir) goto out_free_tr; ret = event_trace_add_tracer(tr->dir, tr); if (ret) { - debugfs_remove_recursive(tr->dir); + tracefs_remove_recursive(tr->dir); goto out_free_tr; } - init_tracer_debugfs(tr, tr->dir); + init_tracer_tracefs(tr, tr->dir); list_add(&tr->list, &ftrace_trace_arrays); @@ -6341,7 +6362,7 @@ static int new_instance_create(const char *name) } -static int instance_delete(const char *name) +static int instance_rmdir(const char *name) { struct trace_array *tr; int found = 0; @@ -6382,82 +6403,17 @@ static int instance_delete(const char *name) return ret; } -static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) -{ - struct dentry *parent; - int ret; - - /* Paranoid: Make sure the parent is the "instances" directory */ - parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias); - if (WARN_ON_ONCE(parent != trace_instance_dir)) - return -ENOENT; - - /* - * The inode mutex is locked, but debugfs_create_dir() will also - * take the mutex. As the instances directory can not be destroyed - * or changed in any other way, it is safe to unlock it, and - * let the dentry try. If two users try to make the same dir at - * the same time, then the new_instance_create() will determine the - * winner. - */ - mutex_unlock(&inode->i_mutex); - - ret = new_instance_create(dentry->d_iname); - - mutex_lock(&inode->i_mutex); - - return ret; -} - -static int instance_rmdir(struct inode *inode, struct dentry *dentry) -{ - struct dentry *parent; - int ret; - - /* Paranoid: Make sure the parent is the "instances" directory */ - parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias); - if (WARN_ON_ONCE(parent != trace_instance_dir)) - return -ENOENT; - - /* The caller did a dget() on dentry */ - mutex_unlock(&dentry->d_inode->i_mutex); - - /* - * The inode mutex is locked, but debugfs_create_dir() will also - * take the mutex. As the instances directory can not be destroyed - * or changed in any other way, it is safe to unlock it, and - * let the dentry try. If two users try to make the same dir at - * the same time, then the instance_delete() will determine the - * winner. - */ - mutex_unlock(&inode->i_mutex); - - ret = instance_delete(dentry->d_iname); - - mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); - mutex_lock(&dentry->d_inode->i_mutex); - - return ret; -} - -static const struct inode_operations instance_dir_inode_operations = { - .lookup = simple_lookup, - .mkdir = instance_mkdir, - .rmdir = instance_rmdir, -}; - static __init void create_trace_instances(struct dentry *d_tracer) { - trace_instance_dir = debugfs_create_dir("instances", d_tracer); + trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, + instance_mkdir, + instance_rmdir); if (WARN_ON(!trace_instance_dir)) return; - - /* Hijack the dir inode operations, to allow mkdir */ - trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; } static void -init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) +init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) { int cpu; @@ -6511,10 +6467,32 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) #endif for_each_tracing_cpu(cpu) - tracing_init_debugfs_percpu(tr, cpu); + tracing_init_tracefs_percpu(tr, cpu); } +static struct vfsmount *trace_automount(void *ingore) +{ + struct vfsmount *mnt; + struct file_system_type *type; + + /* + * To maintain backward compatibility for tools that mount + * debugfs to get to the tracing facility, tracefs is automatically + * mounted to the debugfs/tracing directory. + */ + type = get_fs_type("tracefs"); + if (!type) + return NULL; + mnt = vfs_kern_mount(type, 0, "tracefs", NULL); + put_filesystem(type); + if (IS_ERR(mnt)) + return NULL; + mntget(mnt); + + return mnt; +} + /** * tracing_init_dentry - initialize top level trace array * @@ -6526,23 +6504,30 @@ struct dentry *tracing_init_dentry(void) { struct trace_array *tr = &global_trace; + /* The top level trace array uses NULL as parent */ if (tr->dir) - return tr->dir; + return NULL; if (WARN_ON(!debugfs_initialized())) return ERR_PTR(-ENODEV); - tr->dir = debugfs_create_dir("tracing", NULL); - + /* + * As there may still be users that expect the tracing + * files to exist in debugfs/tracing, we must automount + * the tracefs file system there, so older tools still + * work with the newer kerenl. + */ + tr->dir = debugfs_create_automount("tracing", NULL, + trace_automount, NULL); if (!tr->dir) { pr_warn_once("Could not create debugfs directory 'tracing'\n"); return ERR_PTR(-ENOMEM); } - return tr->dir; + return NULL; } -static __init int tracer_init_debugfs(void) +static __init int tracer_init_tracefs(void) { struct dentry *d_tracer; @@ -6552,7 +6537,7 @@ static __init int tracer_init_debugfs(void) if (IS_ERR(d_tracer)) return 0; - init_tracer_debugfs(&global_trace, d_tracer); + init_tracer_tracefs(&global_trace, d_tracer); trace_create_file("tracing_thresh", 0644, d_tracer, &global_trace, &tracing_thresh_fops); @@ -6575,6 +6560,10 @@ static __init int tracer_init_debugfs(void) create_trace_options_dir(&global_trace); + /* If the tracer was started via cmdline, create options for it here */ + if (global_trace.current_trace != &nop_trace) + update_tracer_options(&global_trace, global_trace.current_trace); + return 0; } @@ -6910,5 +6899,5 @@ __init static int clear_boot_tracer(void) return 0; } -fs_initcall(tracer_init_debugfs); +fs_initcall(tracer_init_tracefs); late_initcall(clear_boot_tracer); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index dd8205a35760..d951deddec89 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -334,7 +334,7 @@ struct tracer_flags { /** - * struct tracer - a specific tracer and its callbacks to interact with debugfs + * struct tracer - a specific tracer and its callbacks to interact with tracefs * @name: the name chosen to select it on the available_tracers file * @init: called when one switches to this tracer (echo name > current_tracer) * @reset: called when one switches to another tracer diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index db54dda10ccc..0d2e47370ee7 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -13,7 +13,7 @@ #include <linux/workqueue.h> #include <linux/spinlock.h> #include <linux/kthread.h> -#include <linux/debugfs.h> +#include <linux/tracefs.h> #include <linux/uaccess.h> #include <linux/module.h> #include <linux/ctype.h> @@ -480,7 +480,7 @@ static void remove_subsystem(struct ftrace_subsystem_dir *dir) return; if (!--dir->nr_events) { - debugfs_remove_recursive(dir->entry); + tracefs_remove_recursive(dir->entry); list_del(&dir->list); __put_system_dir(dir); } @@ -499,7 +499,7 @@ static void remove_event_file_dir(struct ftrace_event_file *file) } spin_unlock(&dir->d_lock); - debugfs_remove_recursive(dir); + tracefs_remove_recursive(dir); } list_del(&file->list); @@ -1526,7 +1526,7 @@ event_subsystem_dir(struct trace_array *tr, const char *name, } else __get_system(system); - dir->entry = debugfs_create_dir(name, parent); + dir->entry = tracefs_create_dir(name, parent); if (!dir->entry) { pr_warn("Failed to create system directory %s\n", name); __put_system(system); @@ -1539,12 +1539,12 @@ event_subsystem_dir(struct trace_array *tr, const char *name, dir->subsystem = system; file->system = dir; - entry = debugfs_create_file("filter", 0644, dir->entry, dir, + entry = tracefs_create_file("filter", 0644, dir->entry, dir, &ftrace_subsystem_filter_fops); if (!entry) { kfree(system->filter); system->filter = NULL; - pr_warn("Could not create debugfs '%s/filter' entry\n", name); + pr_warn("Could not create tracefs '%s/filter' entry\n", name); } trace_create_file("enable", 0644, dir->entry, dir, @@ -1585,9 +1585,9 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file) d_events = parent; name = ftrace_event_name(call); - file->dir = debugfs_create_dir(name, d_events); + file->dir = tracefs_create_dir(name, d_events); if (!file->dir) { - pr_warn("Could not create debugfs '%s' directory\n", name); + pr_warn("Could not create tracefs '%s' directory\n", name); return -1; } @@ -2228,7 +2228,7 @@ static inline int register_event_cmds(void) { return 0; } /* * The top level array has already had its ftrace_event_file * descriptors created in order to allow for early events to - * be recorded. This function is called after the debugfs has been + * be recorded. This function is called after the tracefs has been * initialized, and we now have to create the files associated * to the events. */ @@ -2311,16 +2311,16 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr) struct dentry *d_events; struct dentry *entry; - entry = debugfs_create_file("set_event", 0644, parent, + entry = tracefs_create_file("set_event", 0644, parent, tr, &ftrace_set_event_fops); if (!entry) { - pr_warn("Could not create debugfs 'set_event' entry\n"); + pr_warn("Could not create tracefs 'set_event' entry\n"); return -ENOMEM; } - d_events = debugfs_create_dir("events", parent); + d_events = tracefs_create_dir("events", parent); if (!d_events) { - pr_warn("Could not create debugfs 'events' directory\n"); + pr_warn("Could not create tracefs 'events' directory\n"); return -ENOMEM; } @@ -2412,7 +2412,7 @@ int event_trace_del_tracer(struct trace_array *tr) down_write(&trace_event_sem); __trace_remove_event_dirs(tr); - debugfs_remove_recursive(tr->event_dir); + tracefs_remove_recursive(tr->event_dir); up_write(&trace_event_sem); tr->event_dir = NULL; @@ -2534,10 +2534,10 @@ static __init int event_trace_init(void) if (IS_ERR(d_tracer)) return 0; - entry = debugfs_create_file("available_events", 0444, d_tracer, + entry = tracefs_create_file("available_events", 0444, d_tracer, tr, &ftrace_avail_fops); if (!entry) - pr_warn("Could not create debugfs 'available_events' entry\n"); + pr_warn("Could not create tracefs 'available_events' entry\n"); if (trace_define_common_fields()) pr_warn("tracing: Failed to allocate common fields"); diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 2d25ad1526bb..9cfea4c6d314 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -6,7 +6,6 @@ * is Copyright (c) Steven Rostedt <srostedt@redhat.com> * */ -#include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/ftrace.h> #include <linux/slab.h> @@ -151,7 +150,7 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, * The curr_ret_stack is initialized to -1 and get increased * in this function. So it can be less than -1 only if it was * filtered out via ftrace_graph_notrace_addr() which can be - * set from set_graph_notrace file in debugfs by user. + * set from set_graph_notrace file in tracefs by user. */ if (current->curr_ret_stack < -1) return -EBUSY; @@ -1432,7 +1431,7 @@ static const struct file_operations graph_depth_fops = { .llseek = generic_file_llseek, }; -static __init int init_graph_debugfs(void) +static __init int init_graph_tracefs(void) { struct dentry *d_tracer; @@ -1445,7 +1444,7 @@ static __init int init_graph_debugfs(void) return 0; } -fs_initcall(init_graph_debugfs); +fs_initcall(init_graph_tracefs); static __init int init_graph_trace(void) { diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index d73f565b4e06..ed998fbf09ce 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1310,7 +1310,7 @@ static int unregister_kprobe_event(struct trace_kprobe *tk) return ret; } -/* Make a debugfs interface for controlling probe points */ +/* Make a tracefs interface for controlling probe points */ static __init int init_kprobe_trace(void) { struct dentry *d_tracer; @@ -1323,20 +1323,20 @@ static __init int init_kprobe_trace(void) if (IS_ERR(d_tracer)) return 0; - entry = debugfs_create_file("kprobe_events", 0644, d_tracer, + entry = tracefs_create_file("kprobe_events", 0644, d_tracer, NULL, &kprobe_events_ops); /* Event list interface */ if (!entry) - pr_warning("Could not create debugfs " + pr_warning("Could not create tracefs " "'kprobe_events' entry\n"); /* Profile interface */ - entry = debugfs_create_file("kprobe_profile", 0444, d_tracer, + entry = tracefs_create_file("kprobe_profile", 0444, d_tracer, NULL, &kprobe_profile_ops); if (!entry) - pr_warning("Could not create debugfs " + pr_warning("Could not create tracefs " "'kprobe_profile' entry\n"); return 0; } diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 4f815fbce16d..19aff635841a 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -25,7 +25,7 @@ #include <linux/seq_file.h> #include <linux/slab.h> #include <linux/smp.h> -#include <linux/debugfs.h> +#include <linux/tracefs.h> #include <linux/types.h> #include <linux/string.h> #include <linux/ctype.h> diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c index 75e19e86c954..6cf935316769 100644 --- a/kernel/trace/trace_stat.c +++ b/kernel/trace/trace_stat.c @@ -12,7 +12,7 @@ #include <linux/list.h> #include <linux/slab.h> #include <linux/rbtree.h> -#include <linux/debugfs.h> +#include <linux/tracefs.h> #include "trace_stat.h" #include "trace.h" @@ -65,7 +65,7 @@ static void reset_stat_session(struct stat_session *session) static void destroy_session(struct stat_session *session) { - debugfs_remove(session->file); + tracefs_remove(session->file); __reset_stat_session(session); mutex_destroy(&session->stat_mutex); kfree(session); @@ -279,9 +279,9 @@ static int tracing_stat_init(void) if (IS_ERR(d_tracing)) return 0; - stat_dir = debugfs_create_dir("trace_stat", d_tracing); + stat_dir = tracefs_create_dir("trace_stat", d_tracing); if (!stat_dir) - pr_warning("Could not create debugfs " + pr_warning("Could not create tracefs " "'trace_stat' entry\n"); return 0; } @@ -291,7 +291,7 @@ static int init_stat_file(struct stat_session *session) if (!stat_dir && tracing_stat_init()) return -ENODEV; - session->file = debugfs_create_file(session->ts->name, 0644, + session->file = tracefs_create_file(session->ts->name, 0644, stat_dir, session, &tracing_stat_fops); if (!session->file) |