perf parse-regs: Always build perf register functions

Currently, the macro HAVE_PERF_REGS_SUPPORT is used as a switch to turn
on or turn off the code of perf registers. If any architecture cannot
support perf register, it disables the perf register parsing, for both
the native parsing and cross parsing for other architectures.

To support both the native parsing and cross parsing, the tool should
always build the perf regs functions. Thus, this patch removes
HAVE_PERF_REGS_SUPPORT from the perf regs files.

Signed-off-by: Leo Yan <leo.yan@linux.dev>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: linux-csky@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240214113947.240957-3-leo.yan@linux.dev

perf parse-regs: Introduce functions perf_arch_reg_{ip|sp}()

The current code uses macros PERF_REG_IP and PERF_REG_SP for parsing
registers and we build perf with these macros statically, which means it
only can correctly analyze CPU registers for the native architecture and
fails to support cross analysis (e.g. we build perf on x86 and cannot
analyze Arm64's registers).

We need to generalize util/perf_regs.c for support multi architectures,
as a first step, this commit introduces new functions perf_arch_reg_ip()
and perf_arch_reg_sp(), these two functions dynamically return IP and SP
register index respectively according to the parameter "arch".

Every architecture has its own functions (like __perf_reg_ip_arm64 and
__perf_reg_sp_arm64), these architecture specific functions are defined
in each arch source file under folder util/perf-regs-arch; at the end
all of them are built into the tool for cross analysis.

Committer notes:

Make DWARF_MINIMAL_REGS() an inline function, so that we can use the
__maybe_unused attribute for the 'arch' parameter, as this will avoid a
build failure when that variable is unused in the callers. That happens
when building on unsupported architectures, the ones without
HAVE_PERF_REGS_SUPPORT defined.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Eric Lin <eric.lin@sifive.com>
Cc: Fangrui Song <maskray@google.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Babrou <ivan@cloudflare.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-csky@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Link: https://lore.kernel.org/r/20230606014559.21783-3-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf parse-regs: Refactor arch register parsing functions

Every architecture has a specific register parsing function for
returning register name based on register index, to support cross
analysis (e.g. we use perf x86 binary to parse Arm64's perf data), we
build all these register parsing functions into the tool, this is why
we place all related functions into util/perf_regs.c.

Unfortunately, since util/perf_regs.c needs to include every arch's
perf_regs.h, this easily introduces duplicated definitions coming from
multiple headers, finally it's fragile for building and difficult for
maintenance.

We cannot simply move these register parsing functions into the
corresponding 'arch' folder, the folder is only conditionally built
based on the target architecture.

Therefore, this commit creates a new folder util/perf-regs-arch/ and
uses a dedicated source file to keep every architecture's register
parsing function to avoid definition conflicts.

This is only a refactoring, no functionality change is expected.

Committer notes:

Had to add util/perf-regs-arch/*.c to tools/perf/util/python-ext-sources
to keep 'perf test python' passing.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Eric Lin <eric.lin@sifive.com>
Cc: Fangrui Song <maskray@google.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Babrou <ivan@cloudflare.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-csky@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Link: https://lore.kernel.org/r/20230606014559.21783-2-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>