Merge branch 'tip/tracing/ftrace' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace

1 files changed, 25 insertions, 58 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c8abbb0c8397..d1ef43999d9e 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -299,6 +299,7 @@ static const char *trace_options[] = {
         "sym-userobj",
         "printk-msg-only",
         "context-info",
+        "latency-format",
         NULL
 };
 
@@ -346,6 +347,9 @@ ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
         int len;
         int ret;
 
+        if (!cnt)
+                return 0;
+
         if (s->len <= s->readpos)
                 return -EBUSY;
 
@@ -353,10 +357,12 @@ ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
         if (cnt > len)
                 cnt = len;
         ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt);
-        if (ret)
+        if (ret == cnt)
                 return -EFAULT;
 
-        s->readpos += len;
+        cnt -= ret;
+
+        s->readpos += cnt;
         return cnt;
 }
 
@@ -375,7 +381,7 @@ ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
         if (!ret)
                 return -EFAULT;
 
-        s->readpos += len;
+        s->readpos += cnt;
         return cnt;
 }
 
@@ -1462,33 +1468,6 @@ static void test_cpu_buff_start(struct trace_iterator *iter)
         trace_seq_printf(s, "##### CPU %u buffer started ####\n", iter->cpu);
 }
 
-static enum print_line_t print_lat_fmt(struct trace_iterator *iter)
-{
-        struct trace_seq *s = &iter->seq;
-        unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
-        struct trace_event *event;
-        struct trace_entry *entry = iter->ent;
-
-        test_cpu_buff_start(iter);
-
-        event = ftrace_find_event(entry->type);
-
-        if (trace_flags & TRACE_ITER_CONTEXT_INFO) {
-                if (!trace_print_lat_context(iter))
-                        goto partial;
-        }
-
-        if (event)
-                return event->latency_trace(iter, sym_flags);
-
-        if (!trace_seq_printf(s, "Unknown type %d\n", entry->type))
-                goto partial;
-
-        return TRACE_TYPE_HANDLED;
-partial:
-        return TRACE_TYPE_PARTIAL_LINE;
-}
-
 static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
 {
         struct trace_seq *s = &iter->seq;
@@ -1503,8 +1482,13 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
         event = ftrace_find_event(entry->type);
 
         if (trace_flags & TRACE_ITER_CONTEXT_INFO) {
-                if (!trace_print_context(iter))
-                        goto partial;
+                if (iter->iter_flags & TRACE_FILE_LAT_FMT) {
+                        if (!trace_print_lat_context(iter))
+                                goto partial;
+                } else {
+                        if (!trace_print_context(iter))
+                                goto partial;
+                }
         }
 
         if (event)
@@ -1646,9 +1630,6 @@ static enum print_line_t print_trace_line(struct trace_iterator *iter)
         if (trace_flags & TRACE_ITER_RAW)
                 return print_raw_fmt(iter);
 
-        if (iter->iter_flags & TRACE_FILE_LAT_FMT)
-                return print_lat_fmt(iter);
-
         return print_trace_fmt(iter);
 }
 
@@ -1824,26 +1805,12 @@ static int tracing_open(struct inode *inode, struct file *file)
         iter = __tracing_open(inode, file);
         if (IS_ERR(iter))
                 ret = PTR_ERR(iter);
-
-        return ret;
-}
-
-static int tracing_lt_open(struct inode *inode, struct file *file)
-{
-        struct trace_iterator *iter;
-        int ret = 0;
-
-        iter = __tracing_open(inode, file);
-
-        if (IS_ERR(iter))
-                ret = PTR_ERR(iter);
-        else
+        else if (trace_flags & TRACE_ITER_LATENCY_FMT)
                 iter->iter_flags |= TRACE_FILE_LAT_FMT;
 
         return ret;
 }
 
-
 static void *
 t_next(struct seq_file *m, void *v, loff_t *pos)
 {
@@ -1922,13 +1889,6 @@ static struct file_operations tracing_fops = {
         .release        = tracing_release,
 };
 
-static struct file_operations tracing_lt_fops = {
-        .open           = tracing_lt_open,
-        .read           = seq_read,
-        .llseek         = seq_lseek,
-        .release        = tracing_release,
-};
-
 static struct file_operations show_traces_fops = {
         .open           = show_traces_open,
         .read           = seq_read,
@@ -3049,6 +3009,9 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
         ssize_t ret;
         size_t size;
 
+        if (!count)
+                return 0;
+
         /* Do we have previous read data to read? */
         if (info->read < PAGE_SIZE)
                 goto read;
@@ -3073,8 +3036,10 @@ read:
                 size = count;
 
         ret = copy_to_user(ubuf, info->spare + info->read, size);
-        if (ret)
+        if (ret == size)
                 return -EFAULT;
+        size -= ret;
+
         *ppos += size;
         info->read += size;
 
@@ -3918,8 +3883,10 @@ void ftrace_dump(void)
 
         printk(KERN_TRACE "Dumping ftrace buffer:\n");
 
+        /* Simulate the iterator */
         iter.tr = &global_trace;
         iter.trace = current_trace;
+        iter.cpu_file = TRACE_PIPE_ALL_CPU;
 
         /*
          * We need to stop all tracing on all CPUS to read the