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On risc-v, pref probe generates an invalid syntax for a named register in
a kprobe.
$ perf probe --debug verbose --add "n_tty_write tty"
...
Writing event: p:probe/n_tty_write _text+8922528 tty=%"%a0":x64
Failed to write event: Invalid argument
The problem is the combination of
#define REG_DWARFNUM_NAME(reg, idx) [idx] = "%" #reg
and entries such as
REG_DWARFNUM_NAME("%a0", 10)
where #reg will escape the quotes of the first macro parameter.
Update the macro definition to produce the correct syntax for a named
register in a kprobe, i.e. the unquoted register name with only one
leading %.
Fixes: a90c451918 ("perf riscv: Remove dwarf-regs.c and add dwarf-regs-table.h")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Cc: Ian Rogers <irogers@google.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>