[RFC PATCH 03/10] ftrace: Drop the ftrace_profile_enabled checks in tracing hot path

From: Frederic Weisbecker
Date: Thu Jan 21 2010 - 20:16:43 EST

Every time we enter the function profiler tracing callbacks, we first
check if the function profiling is enabled.

This check is useless because we register the function graph
callbacks only after the hashlist has been initialized.

Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Li Zefan <lizf@xxxxxxxxxxxxxx>
Cc: Lai Jiangshan <laijs@xxxxxxxxxxxxxx>
kernel/trace/ftrace.c | 7 ++-----
1 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 94117ec..f258f67 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -381,13 +381,10 @@ function_profile_call(unsigned long ip, unsigned long parent_ip)
struct func_node *rec;
unsigned long flags;

- if (!ftrace_profile_enabled)
- return;

hlist = &__get_cpu_var(func_hlist_cpu);
- if (!hlist->hash || !ftrace_profile_enabled)
+ if (!hlist->hash)
goto out;

rec = function_find_hlist_node(hlist, ip);
@@ -418,7 +415,7 @@ static void profile_graph_return(struct ftrace_graph_ret *trace)

hlist = &__get_cpu_var(func_hlist_cpu);
- if (!hlist->hash || !ftrace_profile_enabled)
+ if (!hlist->hash)
goto out;

calltime = trace->rettime - trace->calltime;

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