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@@ -53,14 +53,14 @@ size of the mcount call that is embedded in the function).
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For example, if the function foo() calls bar(), when the bar() function calls
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mcount(), the arguments mcount() will pass to the tracer are:
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"frompc" - the address bar() will use to return to foo()
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- "selfpc" - the address bar() (with _mcount() size adjustment)
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+ "selfpc" - the address bar() (with mcount() size adjustment)
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Also keep in mind that this mcount function will be called *a lot*, so
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optimizing for the default case of no tracer will help the smooth running of
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your system when tracing is disabled. So the start of the mcount function is
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-typically the bare min with checking things before returning. That also means
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-the code flow should usually kept linear (i.e. no branching in the nop case).
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-This is of course an optimization and not a hard requirement.
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+typically the bare minimum with checking things before returning. That also
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+means the code flow should usually be kept linear (i.e. no branching in the nop
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+case). This is of course an optimization and not a hard requirement.
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Here is some pseudo code that should help (these functions should actually be
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implemented in assembly):
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@@ -131,10 +131,10 @@ some functions to save (hijack) and restore the return address.
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The mcount function should check the function pointers ftrace_graph_return
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(compare to ftrace_stub) and ftrace_graph_entry (compare to
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-ftrace_graph_entry_stub). If either of those are not set to the relevant stub
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+ftrace_graph_entry_stub). If either of those is not set to the relevant stub
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function, call the arch-specific function ftrace_graph_caller which in turn
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calls the arch-specific function prepare_ftrace_return. Neither of these
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-function names are strictly required, but you should use them anyways to stay
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+function names is strictly required, but you should use them anyway to stay
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consistent across the architecture ports -- easier to compare & contrast
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things.
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@@ -144,7 +144,7 @@ but the first argument should be a pointer to the "frompc". Typically this is
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located on the stack. This allows the function to hijack the return address
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temporarily to have it point to the arch-specific function return_to_handler.
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That function will simply call the common ftrace_return_to_handler function and
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-that will return the original return address with which, you can return to the
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+that will return the original return address with which you can return to the
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original call site.
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Here is the updated mcount pseudo code:
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