tracing: Have trace buffer point back to trace_array

[firefly-linux-kernel-4.4.55.git] / kernel / trace / trace.c

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 801d72b84a2a1927b966d6ed555d9d0c1acecde6..b7f5471ae51898f0f409a3124a6a0faf0c4075f7 100644 (file)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -826,9 +826,12 @@ int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
        if (isspace(ch)) {
                parser->buffer[parser->idx] = 0;
                parser->cont = false;
-       } else {
+       } else if (parser->idx < parser->size - 1) {
                parser->cont = true;
                parser->buffer[parser->idx++] = ch;
+       } else {
+               ret = -EINVAL;
+               goto out;
        }
 
        *ppos += read;
@@ -2853,9 +2856,9 @@ static const struct seq_operations tracer_seq_ops = {
 };
 
 static struct trace_iterator *
-__tracing_open(struct trace_array *tr, struct trace_cpu *tc,
-              struct inode *inode, struct file *file, bool snapshot)
+__tracing_open(struct inode *inode, struct file *file, bool snapshot)
 {
+       struct trace_array *tr = inode->i_private;
        struct trace_iterator *iter;
        int cpu;
 
@@ -2896,8 +2899,8 @@ __tracing_open(struct trace_array *tr, struct trace_cpu *tc,
                iter->trace_buffer = &tr->trace_buffer;
        iter->snapshot = snapshot;
        iter->pos = -1;
+       iter->cpu_file = tracing_get_cpu(inode);
        mutex_init(&iter->mutex);
-       iter->cpu_file = tc->cpu;
 
        /* Notify the tracer early; before we stop tracing. */
        if (iter->trace && iter->trace->open)
@@ -2975,41 +2978,20 @@ int tracing_open_generic_tr(struct inode *inode, struct file *filp)
        return 0;
 }
 
-int tracing_open_generic_tc(struct inode *inode, struct file *filp)
-{
-       struct trace_cpu *tc = inode->i_private;
-       struct trace_array *tr = tc->tr;
-
-       if (tracing_disabled)
-               return -ENODEV;
-
-       if (trace_array_get(tr) < 0)
-               return -ENODEV;
-
-       filp->private_data = inode->i_private;
-
-       return 0;
-
-}
-
 static int tracing_release(struct inode *inode, struct file *file)
 {
+       struct trace_array *tr = inode->i_private;
        struct seq_file *m = file->private_data;
        struct trace_iterator *iter;
-       struct trace_array *tr;
        int cpu;
 
-       /* Writes do not use seq_file, need to grab tr from inode */
        if (!(file->f_mode & FMODE_READ)) {
-               struct trace_cpu *tc = inode->i_private;
-
-               trace_array_put(tc->tr);
+               trace_array_put(tr);
                return 0;
        }
 
+       /* Writes do not use seq_file */
        iter = m->private;
-       tr = iter->tr;
-
        mutex_lock(&trace_types_lock);
 
        for_each_tracing_cpu(cpu) {
@@ -3045,15 +3027,6 @@ static int tracing_release_generic_tr(struct inode *inode, struct file *file)
        return 0;
 }
 
-static int tracing_release_generic_tc(struct inode *inode, struct file *file)
-{
-       struct trace_cpu *tc = inode->i_private;
-       struct trace_array *tr = tc->tr;
-
-       trace_array_put(tr);
-       return 0;
-}
-
 static int tracing_single_release_tr(struct inode *inode, struct file *file)
 {
        struct trace_array *tr = inode->i_private;
@@ -3065,8 +3038,7 @@ static int tracing_single_release_tr(struct inode *inode, struct file *file)
 
 static int tracing_open(struct inode *inode, struct file *file)
 {
-       struct trace_cpu *tc = inode->i_private;
-       struct trace_array *tr = tc->tr;
+       struct trace_array *tr = inode->i_private;
        struct trace_iterator *iter;
        int ret = 0;
 
@@ -3074,16 +3046,17 @@ static int tracing_open(struct inode *inode, struct file *file)
                return -ENODEV;
 
        /* If this file was open for write, then erase contents */
-       if ((file->f_mode & FMODE_WRITE) &&
-           (file->f_flags & O_TRUNC)) {
-               if (tc->cpu == RING_BUFFER_ALL_CPUS)
+       if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
+               int cpu = tracing_get_cpu(inode);
+
+               if (cpu == RING_BUFFER_ALL_CPUS)
                        tracing_reset_online_cpus(&tr->trace_buffer);
                else
-                       tracing_reset(&tr->trace_buffer, tc->cpu);
+                       tracing_reset(&tr->trace_buffer, cpu);
        }
 
        if (file->f_mode & FMODE_READ) {
-               iter = __tracing_open(tr, tc, inode, file, false);
+               iter = __tracing_open(inode, file, false);
                if (IS_ERR(iter))
                        ret = PTR_ERR(iter);
                else if (trace_flags & TRACE_ITER_LATENCY_FMT)
@@ -4374,15 +4347,16 @@ static ssize_t
 tracing_entries_read(struct file *filp, char __user *ubuf,
                     size_t cnt, loff_t *ppos)
 {
-       struct trace_cpu *tc = filp->private_data;
-       struct trace_array *tr = tc->tr;
+       struct inode *inode = file_inode(filp);
+       struct trace_array *tr = inode->i_private;
+       int cpu = tracing_get_cpu(inode);
        char buf[64];
        int r = 0;
        ssize_t ret;
 
        mutex_lock(&trace_types_lock);
 
-       if (tc->cpu == RING_BUFFER_ALL_CPUS) {
+       if (cpu == RING_BUFFER_ALL_CPUS) {
                int cpu, buf_size_same;
                unsigned long size;
 
@@ -4409,7 +4383,7 @@ tracing_entries_read(struct file *filp, char __user *ubuf,
                } else
                        r = sprintf(buf, "X\n");
        } else
-               r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, tc->cpu)->entries >> 10);
+               r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10);
 
        mutex_unlock(&trace_types_lock);
 
@@ -4421,7 +4395,8 @@ static ssize_t
 tracing_entries_write(struct file *filp, const char __user *ubuf,
                      size_t cnt, loff_t *ppos)
 {
-       struct trace_cpu *tc = filp->private_data;
+       struct inode *inode = file_inode(filp);
+       struct trace_array *tr = inode->i_private;
        unsigned long val;
        int ret;
 
@@ -4435,8 +4410,7 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
 
        /* value is in KB */
        val <<= 10;
-
-       ret = tracing_resize_ring_buffer(tc->tr, val, tc->cpu);
+       ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode));
        if (ret < 0)
                return ret;
 
@@ -4697,8 +4671,7 @@ struct ftrace_buffer_info {
 #ifdef CONFIG_TRACER_SNAPSHOT
 static int tracing_snapshot_open(struct inode *inode, struct file *file)
 {
-       struct trace_cpu *tc = inode->i_private;
-       struct trace_array *tr = tc->tr;
+       struct trace_array *tr = inode->i_private;
        struct trace_iterator *iter;
        struct seq_file *m;
        int ret = 0;
@@ -4707,7 +4680,7 @@ static int tracing_snapshot_open(struct inode *inode, struct file *file)
                return -ENODEV;
 
        if (file->f_mode & FMODE_READ) {
-               iter = __tracing_open(tr, tc, inode, file, true);
+               iter = __tracing_open(inode, file, true);
                if (IS_ERR(iter))
                        ret = PTR_ERR(iter);
        } else {
@@ -4724,8 +4697,8 @@ static int tracing_snapshot_open(struct inode *inode, struct file *file)
                ret = 0;
 
                iter->tr = tr;
-               iter->trace_buffer = &tc->tr->max_buffer;
-               iter->cpu_file = tc->cpu;
+               iter->trace_buffer = &tr->max_buffer;
+               iter->cpu_file = tracing_get_cpu(inode);
                m->private = iter;
                file->private_data = m;
        }
@@ -4884,11 +4857,11 @@ static const struct file_operations tracing_pipe_fops = {
 };
 
 static const struct file_operations tracing_entries_fops = {
-       .open           = tracing_open_generic_tc,
+       .open           = tracing_open_generic_tr,
        .read           = tracing_entries_read,
        .write          = tracing_entries_write,
        .llseek         = generic_file_llseek,
-       .release        = tracing_release_generic_tc,
+       .release        = tracing_release_generic_tr,
 };
 
 static const struct file_operations tracing_total_entries_fops = {
@@ -5542,7 +5515,6 @@ 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)
 {
-       struct trace_array_cpu *data = per_cpu_ptr(tr->trace_buffer.data, cpu);
        struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu);
        struct dentry *d_cpu;
        char cpu_dir[30]; /* 30 characters should be more than enough */
@@ -5563,7 +5535,7 @@ tracing_init_debugfs_percpu(struct trace_array *tr, long cpu)
 
        /* per cpu trace */
        trace_create_cpu_file("trace", 0644, d_cpu,
-                               &data->trace_cpu, cpu, &tracing_fops);
+                               tr, cpu, &tracing_fops);
 
        trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu,
                                tr, cpu, &tracing_buffers_fops);
@@ -5572,11 +5544,11 @@ tracing_init_debugfs_percpu(struct trace_array *tr, long cpu)
                                tr, cpu, &tracing_stats_fops);
 
        trace_create_cpu_file("buffer_size_kb", 0444, d_cpu,
-                               &data->trace_cpu, cpu, &tracing_entries_fops);
+                               tr, cpu, &tracing_entries_fops);
 
 #ifdef CONFIG_TRACER_SNAPSHOT
        trace_create_cpu_file("snapshot", 0644, d_cpu,
-                               &data->trace_cpu, cpu, &snapshot_fops);
+                               tr, cpu, &snapshot_fops);
 
        trace_create_cpu_file("snapshot_raw", 0444, d_cpu,
                                tr, cpu, &snapshot_raw_fops);
@@ -5906,6 +5878,8 @@ allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size
 
        rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;
 
+       buf->tr = tr;
+
        buf->buffer = ring_buffer_alloc(size, rb_flags);
        if (!buf->buffer)
                return -ENOMEM;
@@ -6142,13 +6116,13 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
                          tr, &tracing_iter_fops);
 
        trace_create_file("trace", 0644, d_tracer,
-                       (void *)&tr->trace_cpu, &tracing_fops);
+                         tr, &tracing_fops);
 
        trace_create_file("trace_pipe", 0444, d_tracer,
                          tr, &tracing_pipe_fops);
 
        trace_create_file("buffer_size_kb", 0644, d_tracer,
-                       (void *)&tr->trace_cpu, &tracing_entries_fops);
+                         tr, &tracing_entries_fops);
 
        trace_create_file("buffer_total_size_kb", 0444, d_tracer,
                          tr, &tracing_total_entries_fops);
@@ -6163,11 +6137,11 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
                          &trace_clock_fops);
 
        trace_create_file("tracing_on", 0644, d_tracer,
-                           tr, &rb_simple_fops);
+                         tr, &rb_simple_fops);
 
 #ifdef CONFIG_TRACER_SNAPSHOT
        trace_create_file("snapshot", 0644, d_tracer,
-                         (void *)&tr->trace_cpu, &snapshot_fops);
+                         tr, &snapshot_fops);
 #endif
 
        for_each_tracing_cpu(cpu)