Commit Graph

4 Commits

Author SHA1 Message Date
Christoph Hellwig f31b8de988
RISC-V: remove the unused return_to_handler export
This export is not only not needed, but also breaks symbol versioning
due to being an undeclared assembly export.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22 17:38:12 -07:00
Alan Kao 1dd985229d
riscv/ftrace: Export _mcount when DYNAMIC_FTRACE isn't set
The EXPORT_SYMBOL(_mcount) for RISC-V ended up inside a
CONFIG_DYNAMIC_FTRACE ifdef.  If you enable modules without enabling
CONFIG_DYNAMIC_FTRACE then you'll get a build error without this patch
because the modules won't be able to find _mcount.

The new behavior is to export _mcount whenever CONFIG_FUNCTION_TRACER is
defined.  This matches what every other architecture is doing.

Signed-off-by: Alan Kao <alankao@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Zong Li <zong@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-06-11 09:04:03 -07:00
Alan Kao c15ac4fd60
riscv/ftrace: Add dynamic function tracer support
We now have dynamic ftrace with the following added items:

* ftrace_make_call, ftrace_make_nop (in kernel/ftrace.c)
  The two functions turn each recorded call site of filtered functions
  into a call to ftrace_caller or nops

* ftracce_update_ftrace_func (in kernel/ftrace.c)
  turns the nops at ftrace_call into a call to a generic entry for
  function tracers.

* ftrace_caller (in kernel/mcount-dyn.S)
  The entry where each _mcount call sites calls to once they are
  filtered to be traced.

Also, this patch fixes the semantic problems in mcount.S, which will be
treated as only a reference implementation once we have the dynamic
ftrace.

Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02 19:59:12 -07:00
Alan Kao 10626c32e3
riscv/ftrace: Add basic support
This patch contains basic ftrace support for RV64I platform.
Specifically, function tracer (HAVE_FUNCTION_TRACER), function graph
tracer (HAVE_FUNCTION_GRAPH_TRACER), and a frame pointer test
(HAVE_FUNCTION_GRAPH_FP_TEST) are implemented following the
instructions in Documentation/trace/ftrace-design.txt.

Note that the functions in both ftrace.c and setup.c should not be
hooked with the compiler's -pg option: to prevent infinite self-
referencing for the former, and to ignore early setup stuff for the
latter.

Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-01-30 19:10:54 -08:00