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tracing/function-graph-tracer: introduce __notrace_funcgraph to filter special functions

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Impact: trace more functions

When the function graph tracer is configured, three more files are not
traced to prevent only four functions to be traced. And this impacts the
normal function tracer too.

arch/x86/kernel/process_64/32.c:

I had crashes when I let this file traced. After some debugging, I saw
that the "current" task point was changed inside__swtich_to(), ie:
"write_pda(pcurrent, next_p);" inside process_64.c Since the tracer store
the original return address of the function inside current, we had
crashes. Only __switch_to() has to be excluded from tracing.

kernel/module.c and kernel/extable.c:

Because of a function used internally by the function graph tracer:
__kernel_text_address()

To let the other functions inside these files to be traced, this patch
introduces the __notrace_funcgraph function prefix which is __notrace if
function graph tracer is configured and nothing if not.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Frederic Weisbecker
2008-12-06 03:40:00 +01:00
committed by Ingo Molnar
parent decbec3838
commit 8b96f01198
7 changed files with 21 additions and 15 deletions
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2
kernel/module.c
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@@ -2704,7 +2704,7 @@ int is_module_address(unsigned long addr)
/* Is this a valid kernel address? */
struct module *__module_text_address(unsigned long addr)
__notrace_funcgraph struct module *__module_text_address(unsigned long addr)
{
struct module *mod;