perf augmented_raw_syscalls.bpf: Move 'struct timespec64' to vmlinux.h

If we instead decide to generate vmlinux.h from BTF info, it will be
there:

$ pahole timespec64
struct timespec64 {
time64_t tv_sec; /* 0 8 */
long int tv_nsec; /* 8 8 */

/* size: 16, cachelines: 1, members: 2 */
/* last cacheline: 16 bytes */
};

$

pahole manages to find it from /sys/kernel/btf/vmlinux, that is
generated from the kernel types.

With this linux/bpf.h doesn't need to be included, as its already in the
minimalistic tools/perf/util/bpf_skel/vmlinux/vmlinux.h file or what we
need comes when generating a vmlinux.h file from BTF info, i.e. when
using GEN_VMLINUX_H=1, as noticed by Namyung in a build break before
removing linux/bpf.h.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/Zc_fp6CgDClPhS_O@x1

perf bpf: Move the declaration of struct rq

struct rq is defined in vmlinux.h when the vmlinux.h is generated,
this causes a redefinition failure if it is declared in
lock_contention.bpf.c. Move the definition to vmlinux.h for
consistency with the generated version.

Fixes: 760ebc45746b ("perf lock contention: Add empty 'struct rq' to satisfy libbpf 'runqueue' type verification")
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: James Clark <james.clark@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230623041405.4039475-3-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

perf build: Add ability to build with a generated vmlinux.h

Commit a887466562b4 ("perf bpf skels: Stop using vmlinux.h generated
from BTF, use subset of used structs + CO-RE") made it so that
vmlinux.h was uncondtionally included from
tools/perf/util/vmlinux.h. This change reverts part of that change (so
that vmlinux.h is once again generated) and makes it so that the
vmlinux.h used at build time is selected from the VMLINUX_H
variable. By default the VMLINUX_H variable is set to the vmlinux.h
added in change a887466562b4, but if GEN_VMLINUX_H=1 is passed on the
build command line then the previous generation behavior kicks in.

The build with GEN_VMLINUX_H=1 currently fails with:

util/bpf_skel/lock_contention.bpf.c:419:8: error: redefinition of 'rq'
struct rq {};
^
/tmp/perf/util/bpf_skel/.tmp/../vmlinux.h:45630:8: note: previous definition is here
struct rq {
^
1 error generated.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: James Clark <james.clark@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230623041405.4039475-2-irogers@google.com
[ Format the error message and add a comment for GEN_VMLINUX_H ]
Signed-off-by: Namhyung Kim <namhyung@kernel.org>