1 files changed, 91 insertions, 124 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index bb60732ade0c..8c804e24f96f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -291,7 +291,9 @@ function_stat_next(void *v, int idx)
         pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK);
 
  again:
-        rec++;
+        if (idx != 0)
+                rec++;
+
         if ((void *)rec >= (void *)&pg->records[pg->index]) {
                 pg = pg->next;
                 if (!pg)
@@ -766,7 +768,7 @@ static struct tracer_stat function_stats __initdata = {
         .stat_show      = function_stat_show
 };
 
-static void ftrace_profile_debugfs(struct dentry *d_tracer)
+static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
 {
         struct ftrace_profile_stat *stat;
         struct dentry *entry;
@@ -784,7 +786,6 @@ static void ftrace_profile_debugfs(struct dentry *d_tracer)
                          * The files created are permanent, if something happens
                          * we still do not free memory.
                          */
-                        kfree(stat);
                         WARN(1,
                              "Could not allocate stat file for cpu %d\n",
                              cpu);
@@ -811,7 +812,7 @@ static void ftrace_profile_debugfs(struct dentry *d_tracer)
 }
 
 #else /* CONFIG_FUNCTION_PROFILER */
-static void ftrace_profile_debugfs(struct dentry *d_tracer)
+static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
 {
 }
 #endif /* CONFIG_FUNCTION_PROFILER */
@@ -1015,71 +1016,35 @@ static int
 __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
 {
         unsigned long ftrace_addr;
-        unsigned long ip, fl;
+        unsigned long flag = 0UL;
 
         ftrace_addr = (unsigned long)FTRACE_ADDR;
 
-        ip = rec->ip;
-
         /*
-         * If this record is not to be traced and
-         * it is not enabled then do nothing.
+         * If this record is not to be traced or we want to disable it,
+         * then disable it.
          *
-         * If this record is not to be traced and
-         * it is enabled then disable it.
+         * If we want to enable it and filtering is off, then enable it.
          *
+         * If we want to enable it and filtering is on, enable it only if
+         * it's filtered
          */
-        if (rec->flags & FTRACE_FL_NOTRACE) {
-                if (rec->flags & FTRACE_FL_ENABLED)
-                        rec->flags &= ~FTRACE_FL_ENABLED;
-                else
-                        return 0;
-
-        } else if (ftrace_filtered && enable) {
-                /*
-                 * Filtering is on:
-                 */
-
-                fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED);
-
-                /* Record is filtered and enabled, do nothing */
-                if (fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED))
-                        return 0;
-
-                /* Record is not filtered or enabled, do nothing */
-                if (!fl)
-                        return 0;
-
-                /* Record is not filtered but enabled, disable it */
-                if (fl == FTRACE_FL_ENABLED)
-                        rec->flags &= ~FTRACE_FL_ENABLED;
-                else
-                /* Otherwise record is filtered but not enabled, enable it */
-                        rec->flags |= FTRACE_FL_ENABLED;
-        } else {
-                /* Disable or not filtered */
-
-                if (enable) {
-                        /* if record is enabled, do nothing */
-                        if (rec->flags & FTRACE_FL_ENABLED)
-                                return 0;
-
-                        rec->flags |= FTRACE_FL_ENABLED;
-
-                } else {
+        if (enable && !(rec->flags & FTRACE_FL_NOTRACE)) {
+                if (!ftrace_filtered || (rec->flags & FTRACE_FL_FILTER))
+                        flag = FTRACE_FL_ENABLED;
+        }
 
-                        /* if record is not enabled, do nothing */
-                        if (!(rec->flags & FTRACE_FL_ENABLED))
-                                return 0;
+        /* If the state of this record hasn't changed, then do nothing */
+        if ((rec->flags & FTRACE_FL_ENABLED) == flag)
+                return 0;
 
-                        rec->flags &= ~FTRACE_FL_ENABLED;
-                }
+        if (flag) {
+                rec->flags |= FTRACE_FL_ENABLED;
+                return ftrace_make_call(rec, ftrace_addr);
         }
 
-        if (rec->flags & FTRACE_FL_ENABLED)
-                return ftrace_make_call(rec, ftrace_addr);
-        else
-                return ftrace_make_nop(NULL, rec, ftrace_addr);
+        rec->flags &= ~FTRACE_FL_ENABLED;
+        return ftrace_make_nop(NULL, rec, ftrace_addr);
 }
 
 static void ftrace_replace_code(int enable)
@@ -1224,6 +1189,13 @@ static void ftrace_shutdown(int command)
                 return;
 
         ftrace_start_up--;
+        /*
+         * Just warn in case of unbalance, no need to kill ftrace, it's not
+         * critical but the ftrace_call callers may be never nopped again after
+         * further ftrace uses.
+         */
+        WARN_ON_ONCE(ftrace_start_up < 0);
+
         if (!ftrace_start_up)
                 command |= FTRACE_DISABLE_CALLS;
 
@@ -1367,7 +1339,6 @@ struct ftrace_iterator {
         unsigned                flags;
         unsigned char           buffer[FTRACE_BUFF_MAX+1];
         unsigned                buffer_idx;
-        unsigned                filtered;
 };
 
 static void *
@@ -1410,28 +1381,33 @@ static void *t_hash_start(struct seq_file *m, loff_t *pos)
 {
         struct ftrace_iterator *iter = m->private;
         void *p = NULL;
+        loff_t l;
+
+        if (!(iter->flags & FTRACE_ITER_HASH))
+                *pos = 0;
 
         iter->flags |= FTRACE_ITER_HASH;
 
-        return t_hash_next(m, p, pos);
+        iter->hidx = 0;
+        for (l = 0; l <= *pos; ) {
+                p = t_hash_next(m, p, &l);
+                if (!p)
+                        break;
+        }
+        return p;
 }
 
 static int t_hash_show(struct seq_file *m, void *v)
 {
         struct ftrace_func_probe *rec;
         struct hlist_node *hnd = v;
-        char str[KSYM_SYMBOL_LEN];
 
         rec = hlist_entry(hnd, struct ftrace_func_probe, node);
 
         if (rec->ops->print)
                 return rec->ops->print(m, rec->ip, rec->ops, rec->data);
 
-        kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
-        seq_printf(m, "%s:", str);
-
-        kallsyms_lookup((unsigned long)rec->ops->func, NULL, NULL, NULL, str);
-        seq_printf(m, "%s", str);
+        seq_printf(m, "%pf:%pf", (void *)rec->ip, (void *)rec->ops->func);
 
         if (rec->data)
                 seq_printf(m, ":%p", rec->data);
@@ -1460,8 +1436,6 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
                         iter->pg = iter->pg->next;
                         iter->idx = 0;
                         goto retry;
-                } else {
-                        iter->idx = -1;
                 }
         } else {
                 rec = &iter->pg->records[iter->idx++];
@@ -1490,6 +1464,7 @@ static void *t_start(struct seq_file *m, loff_t *pos)
 {
         struct ftrace_iterator *iter = m->private;
         void *p = NULL;
+        loff_t l;
 
         mutex_lock(&ftrace_lock);
         /*
@@ -1501,23 +1476,21 @@ static void *t_start(struct seq_file *m, loff_t *pos)
                 if (*pos > 0)
                         return t_hash_start(m, pos);
                 iter->flags |= FTRACE_ITER_PRINTALL;
-                (*pos)++;
                 return iter;
         }
 
         if (iter->flags & FTRACE_ITER_HASH)
                 return t_hash_start(m, pos);
 
-        if (*pos > 0) {
-                if (iter->idx < 0)
-                        return p;
-                (*pos)--;
-                iter->idx--;
+        iter->pg = ftrace_pages_start;
+        iter->idx = 0;
+        for (l = 0; l <= *pos; ) {
+                p = t_next(m, p, &l);
+                if (!p)
+                        break;
         }
 
-        p = t_next(m, p, pos);
-
-        if (!p)
+        if (!p && iter->flags & FTRACE_ITER_FILTER)
                 return t_hash_start(m, pos);
 
         return p;
@@ -1532,7 +1505,6 @@ static int t_show(struct seq_file *m, void *v)
 {
         struct ftrace_iterator *iter = m->private;
         struct dyn_ftrace *rec = v;
-        char str[KSYM_SYMBOL_LEN];
 
         if (iter->flags & FTRACE_ITER_HASH)
                 return t_hash_show(m, v);
@@ -1545,9 +1517,7 @@ static int t_show(struct seq_file *m, void *v)
         if (!rec)
                 return 0;
 
-        kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
-
-        seq_printf(m, "%s\n", str);
+        seq_printf(m, "%pf\n", (void *)rec->ip);
 
         return 0;
 }
@@ -1586,17 +1556,6 @@ ftrace_avail_open(struct inode *inode, struct file *file)
         return ret;
 }
 
-int ftrace_avail_release(struct inode *inode, struct file *file)
-{
-        struct seq_file *m = (struct seq_file *)file->private_data;
-        struct ftrace_iterator *iter = m->private;
-
-        seq_release(inode, file);
-        kfree(iter);
-
-        return 0;
-}
-
 static int
 ftrace_failures_open(struct inode *inode, struct file *file)
 {
@@ -1647,7 +1606,7 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
 
         mutex_lock(&ftrace_regex_lock);
         if ((file->f_mode & FMODE_WRITE) &&
-            !(file->f_flags & O_APPEND))
+            (file->f_flags & O_TRUNC))
                 ftrace_filter_reset(enable);
 
         if (file->f_mode & FMODE_READ) {
@@ -2263,7 +2222,11 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
         read++;
         cnt--;
 
-        if (!(iter->flags & ~FTRACE_ITER_CONT)) {
+        /*
+         * If the parser haven't finished with the last write,
+         * continue reading the user input without skipping spaces.
+         */
+        if (!(iter->flags & FTRACE_ITER_CONT)) {
                 /* skip white space */
                 while (cnt && isspace(ch)) {
                         ret = get_user(ch, ubuf++);
@@ -2273,8 +2236,9 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
                         cnt--;
                 }
 
+                /* only spaces were written */
                 if (isspace(ch)) {
-                        file->f_pos += read;
+                        *ppos += read;
                         ret = read;
                         goto out;
                 }
@@ -2297,19 +2261,18 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
         }
 
         if (isspace(ch)) {
-                iter->filtered++;
                 iter->buffer[iter->buffer_idx] = 0;
                 ret = ftrace_process_regex(iter->buffer,
                                            iter->buffer_idx, enable);
                 if (ret)
                         goto out;
                 iter->buffer_idx = 0;
-        } else
+        } else {
                 iter->flags |= FTRACE_ITER_CONT;
+                iter->buffer[iter->buffer_idx++] = ch;
+        }
 
-
-        file->f_pos += read;
-
+        *ppos += read;
         ret = read;
  out:
         mutex_unlock(&ftrace_regex_lock);
@@ -2428,7 +2391,6 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
                 iter = file->private_data;
 
         if (iter->buffer_idx) {
-                iter->filtered++;
                 iter->buffer[iter->buffer_idx] = 0;
                 ftrace_match_records(iter->buffer, iter->buffer_idx, enable);
         }
@@ -2459,14 +2421,14 @@ static const struct file_operations ftrace_avail_fops = {
         .open = ftrace_avail_open,
         .read = seq_read,
         .llseek = seq_lseek,
-        .release = ftrace_avail_release,
+        .release = seq_release_private,
 };
 
 static const struct file_operations ftrace_failures_fops = {
         .open = ftrace_failures_open,
         .read = seq_read,
         .llseek = seq_lseek,
-        .release = ftrace_avail_release,
+        .release = seq_release_private,
 };
 
 static const struct file_operations ftrace_filter_fops = {
@@ -2493,32 +2455,31 @@ int ftrace_graph_count;
 unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
 
 static void *
-g_next(struct seq_file *m, void *v, loff_t *pos)
+__g_next(struct seq_file *m, loff_t *pos)
 {
         unsigned long *array = m->private;
-        int index = *pos;
-
-        (*pos)++;
 
-        if (index >= ftrace_graph_count)
+        if (*pos >= ftrace_graph_count)
                 return NULL;
+        return &array[*pos];
+}
 
-        return &array[index];
+static void *
+g_next(struct seq_file *m, void *v, loff_t *pos)
+{
+        (*pos)++;
+        return __g_next(m, pos);
 }
 
 static void *g_start(struct seq_file *m, loff_t *pos)
 {
-        void *p = NULL;
-
         mutex_lock(&graph_lock);
 
         /* Nothing, tell g_show to print all functions are enabled */
         if (!ftrace_graph_count && !*pos)
                 return (void *)1;
 
-        p = g_next(m, p, pos);
-
-        return p;
+        return __g_next(m, pos);
 }
 
 static void g_stop(struct seq_file *m, void *p)
@@ -2529,7 +2490,6 @@ static void g_stop(struct seq_file *m, void *p)
 static int g_show(struct seq_file *m, void *v)
 {
         unsigned long *ptr = v;
-        char str[KSYM_SYMBOL_LEN];
 
         if (!ptr)
                 return 0;
@@ -2539,9 +2499,7 @@ static int g_show(struct seq_file *m, void *v)
                 return 0;
         }
 
-        kallsyms_lookup(*ptr, NULL, NULL, NULL, str);
-
-        seq_printf(m, "%s\n", str);
+        seq_printf(m, "%pf\n", v);
 
         return 0;
 }
@@ -2563,7 +2521,7 @@ ftrace_graph_open(struct inode *inode, struct file *file)
 
         mutex_lock(&graph_lock);
         if ((file->f_mode & FMODE_WRITE) &&
-            !(file->f_flags & O_APPEND)) {
+            (file->f_flags & O_TRUNC)) {
                 ftrace_graph_count = 0;
                 memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs));
         }
@@ -2582,6 +2540,14 @@ ftrace_graph_open(struct inode *inode, struct file *file)
 }
 
 static int
+ftrace_graph_release(struct inode *inode, struct file *file)
+{
+        if (file->f_mode & FMODE_READ)
+                seq_release(inode, file);
+        return 0;
+}
+
+static int
 ftrace_set_func(unsigned long *array, int *idx, char *buffer)
 {
         struct dyn_ftrace *rec;
@@ -2710,9 +2676,10 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
 }
 
 static const struct file_operations ftrace_graph_fops = {
-        .open = ftrace_graph_open,
-        .read = seq_read,
-        .write = ftrace_graph_write,
+        .open           = ftrace_graph_open,
+        .read           = seq_read,
+        .write          = ftrace_graph_write,
+        .release        = ftrace_graph_release,
 };
 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 
@@ -3145,10 +3112,10 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
 
         ret  = proc_dointvec(table, write, file, buffer, lenp, ppos);
 
-        if (ret || !write || (last_ftrace_enabled == ftrace_enabled))
+        if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
                 goto out;
 
-        last_ftrace_enabled = ftrace_enabled;
+        last_ftrace_enabled = !!ftrace_enabled;
 
         if (ftrace_enabled) {