[PATCH 5/5] uprobes: Kill trace_uprobe->enabled, introduce is_trace_uprobe_enabled()

Oleg Nesterov
2013-01-28T18:26:31Z

Finally kill trace_uprobe->enabled and add is_trace_uprobe_enabled()
which can rely on TP_FLAG_TRACE/TP_FLAG_PROFILE bits we set/clear
anyway.

Note that we could do this from the very beginning, ->enabled was
never strictly needed. But I'd prefer to do this as a last change
so that it can be dropped if the reviewers do not like the (ab)use
of tu->flags.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
kernel/trace/trace_uprobe.c | 13 +++++++------
1 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 642e003..1e1633c 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -40,7 +40,6 @@ struct trace_uprobe {
struct list_head list;
struct ftrace_event_class class;
struct ftrace_event_call call;
- bool enabled;
struct uprobe_consumer consumer;
struct trace_uprobe_filter filter;
struct inode *inode;
@@ -633,31 +632,33 @@ partial:
return TRACE_TYPE_PARTIAL_LINE;
}

+static inline bool is_trace_uprobe_enabled(struct trace_uprobe *tu)
+{
+ return tu->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE);
+}
+
static int probe_event_enable(struct trace_uprobe *tu, int flag)
{
int ret = 0;

- if (tu->enabled)
+ if (is_trace_uprobe_enabled(tu))
return -EINTR;

tu->flags |= flag;
ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
if (ret)
tu->flags &= ~flag;
- else
- tu->enabled = true;

return ret;
}

static void probe_event_disable(struct trace_uprobe *tu, int flag)
{
- if (!tu->enabled)
+ if (!is_trace_uprobe_enabled(tu))
return;

uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
tu->flags &= ~flag;
- tu->enabled = false;
}

static int uprobe_event_define_fields(struct ftrace_event_call *event_call)
--
1.5.5.1