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-rw-r--r--kernel/trace/trace.c54
1 files changed, 19 insertions, 35 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 73e67b68c53b..2a8d8a294345 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -362,7 +362,7 @@ trace_ignore_this_task(struct trace_pid_list *filtered_pids, struct task_struct
}
/**
- * trace_pid_filter_add_remove - Add or remove a task from a pid_list
+ * trace_pid_filter_add_remove_task - Add or remove a task from a pid_list
* @pid_list: The list to modify
* @self: The current task for fork or NULL for exit
* @task: The task to add or remove
@@ -925,7 +925,7 @@ static void tracing_snapshot_instance(struct trace_array *tr)
}
/**
- * trace_snapshot - take a snapshot of the current buffer.
+ * tracing_snapshot - take a snapshot of the current buffer.
*
* This causes a swap between the snapshot buffer and the current live
* tracing buffer. You can use this to take snapshots of the live
@@ -1004,9 +1004,9 @@ int tracing_alloc_snapshot(void)
EXPORT_SYMBOL_GPL(tracing_alloc_snapshot);
/**
- * trace_snapshot_alloc - allocate and take a snapshot of the current buffer.
+ * tracing_snapshot_alloc - allocate and take a snapshot of the current buffer.
*
- * This is similar to trace_snapshot(), but it will allocate the
+ * This is similar to tracing_snapshot(), but it will allocate the
* snapshot buffer if it isn't already allocated. Use this only
* where it is safe to sleep, as the allocation may sleep.
*
@@ -1303,7 +1303,7 @@ unsigned long __read_mostly tracing_thresh;
/*
* Copy the new maximum trace into the separate maximum-trace
* structure. (this way the maximum trace is permanently saved,
- * for later retrieval via /sys/kernel/debug/tracing/latency_trace)
+ * for later retrieval via /sys/kernel/tracing/tracing_max_latency)
*/
static void
__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
@@ -2415,7 +2415,7 @@ trace_process_export(struct trace_export *export,
entry = ring_buffer_event_data(event);
size = ring_buffer_event_length(event);
- export->write(entry, size);
+ export->write(export, entry, size);
}
static DEFINE_MUTEX(ftrace_export_lock);
@@ -4178,37 +4178,30 @@ static const struct file_operations show_traces_fops = {
.llseek = seq_lseek,
};
-/*
- * The tracer itself will not take this lock, but still we want
- * to provide a consistent cpumask to user-space:
- */
-static DEFINE_MUTEX(tracing_cpumask_update_lock);
-
-/*
- * Temporary storage for the character representation of the
- * CPU bitmask (and one more byte for the newline):
- */
-static char mask_str[NR_CPUS + 1];
-
static ssize_t
tracing_cpumask_read(struct file *filp, char __user *ubuf,
size_t count, loff_t *ppos)
{
struct trace_array *tr = file_inode(filp)->i_private;
+ char *mask_str;
int len;
- mutex_lock(&tracing_cpumask_update_lock);
+ len = snprintf(NULL, 0, "%*pb\n",
+ cpumask_pr_args(tr->tracing_cpumask)) + 1;
+ mask_str = kmalloc(len, GFP_KERNEL);
+ if (!mask_str)
+ return -ENOMEM;
- len = snprintf(mask_str, count, "%*pb\n",
+ len = snprintf(mask_str, len, "%*pb\n",
cpumask_pr_args(tr->tracing_cpumask));
if (len >= count) {
count = -EINVAL;
goto out_err;
}
- count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1);
+ count = simple_read_from_buffer(ubuf, count, ppos, mask_str, len);
out_err:
- mutex_unlock(&tracing_cpumask_update_lock);
+ kfree(mask_str);
return count;
}
@@ -4228,8 +4221,6 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
if (err)
goto err_unlock;
- mutex_lock(&tracing_cpumask_update_lock);
-
local_irq_disable();
arch_spin_lock(&tr->max_lock);
for_each_tracing_cpu(cpu) {
@@ -4252,8 +4243,6 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
local_irq_enable();
cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new);
-
- mutex_unlock(&tracing_cpumask_update_lock);
free_cpumask_var(tracing_cpumask_new);
return count;
@@ -6780,7 +6769,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
.spd_release = buffer_spd_release,
};
struct buffer_ref *ref;
- int entries, size, i;
+ int entries, i;
ssize_t ret = 0;
#ifdef CONFIG_TRACER_MAX_TRACE
@@ -6834,14 +6823,6 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
break;
}
- /*
- * zero out any left over data, this is going to
- * user land.
- */
- size = ring_buffer_page_len(ref->page);
- if (size < PAGE_SIZE)
- memset(ref->page + size, 0, PAGE_SIZE - size);
-
page = virt_to_page(ref->page);
spd.pages[i] = page;
@@ -7599,6 +7580,7 @@ allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size
buf->data = alloc_percpu(struct trace_array_cpu);
if (!buf->data) {
ring_buffer_free(buf->buffer);
+ buf->buffer = NULL;
return -ENOMEM;
}
@@ -7622,7 +7604,9 @@ static int allocate_trace_buffers(struct trace_array *tr, int size)
allocate_snapshot ? size : 1);
if (WARN_ON(ret)) {
ring_buffer_free(tr->trace_buffer.buffer);
+ tr->trace_buffer.buffer = NULL;
free_percpu(tr->trace_buffer.data);
+ tr->trace_buffer.data = NULL;
return -ENOMEM;
}
tr->allocated_snapshot = allocate_snapshot;