| From | Arnaldo Carvalho de Melo <> | Subject | [PATCH 06/37] perf bpf: Add BPF_PROLOGUE config options for further patches | Date | Thu, 19 Nov 2015 14:52:52 -0300 |
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From: Wang Nan <wangnan0@huawei.com>
If both LIBBPF and DWARF are detected, it is possible to create prologue for eBPF programs to help them access kernel data. HAVE_BPF_PROLOGUE and CONFIG_BPF_PROLOGUE are added as flags for this feature.
PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET is introduced in commit 63ab024a5b6f295ca17a293ad81b7c728f49a89a ("perf tools: regs_query_register_offset() infrastructure"), which indicates that an architecture supports converting name of a register to its offset in 'struct pt_regs'. Without this support, BPF_PROLOGUE should be turned off.
Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1447675815-166222-9-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> --- tools/perf/config/Makefile | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile index de89ec574361..6eb9a956a408 100644 --- a/tools/perf/config/Makefile +++ b/tools/perf/config/Makefile @@ -318,6 +318,18 @@ ifndef NO_LIBELF CFLAGS += -DHAVE_LIBBPF_SUPPORT $(call detected,CONFIG_LIBBPF) endif + + ifndef NO_DWARF + ifdef PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET + CFLAGS += -DHAVE_BPF_PROLOGUE + $(call detected,CONFIG_BPF_PROLOGUE) + else + msg := $(warning BPF prologue is not supported by architecture $(ARCH), missing regs_query_register_offset()); + endif + else + msg := $(warning DWARF support is off, BPF prologue is disabled); + endif + endif # NO_LIBBPF endif # NO_LIBELF -- 2.1.0
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