summaryrefslogtreecommitdiffstats
path: root/tools/lib/bpf
diff options
context:
space:
mode:
authorAndrii Nakryiko <andriin@fb.com>2020-08-18 18:36:07 -0700
committerAlexei Starovoitov <ast@kernel.org>2020-08-18 18:38:25 -0700
commit22dd1ac91a77675238d10059c479ab6fa6160c60 (patch)
treedb9db9e5bf0e08e319156582f83936d0f74a95cd /tools/lib/bpf
parent85367030a6c7ef3373347cf816c698995074f6f0 (diff)
downloadlinux-22dd1ac91a77675238d10059c479ab6fa6160c60.tar.gz
linux-22dd1ac91a77675238d10059c479ab6fa6160c60.tar.bz2
linux-22dd1ac91a77675238d10059c479ab6fa6160c60.zip
tools: Remove feature-libelf-mmap feature detection
It's trivial to handle missing ELF_C_MMAP_READ support in libelf the way that objtool has solved it in ("774bec3fddcc objtool: Add fallback from ELF_C_READ_MMAP to ELF_C_READ"). So instead of having an entire feature detector for that, just do what objtool does for perf and libbpf. And keep their Makefiles a bit simpler. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200819013607.3607269-5-andriin@fb.com
Diffstat (limited to 'tools/lib/bpf')
-rw-r--r--tools/lib/bpf/Makefile6
-rw-r--r--tools/lib/bpf/libbpf.c14
2 files changed, 7 insertions, 13 deletions
diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
index 621ad96d06fd..c5dbfafdf889 100644
--- a/tools/lib/bpf/Makefile
+++ b/tools/lib/bpf/Makefile
@@ -56,7 +56,7 @@ ifndef VERBOSE
endif
FEATURE_USER = .libbpf
-FEATURE_TESTS = libelf libelf-mmap zlib bpf
+FEATURE_TESTS = libelf zlib bpf
FEATURE_DISPLAY = libelf zlib bpf
INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi
@@ -98,10 +98,6 @@ else
CFLAGS := -g -Wall
endif
-ifeq ($(feature-libelf-mmap), 1)
- override CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT
-endif
-
# Append required CFLAGS
override CFLAGS += $(EXTRA_WARNINGS) -Wno-switch-enum
override CFLAGS += -Werror -Wall
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 4b96e0eefea8..4a81c6b2d21b 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -150,12 +150,6 @@ static void pr_perm_msg(int err)
___err; })
#endif
-#ifdef HAVE_LIBELF_MMAP_SUPPORT
-# define LIBBPF_ELF_C_READ_MMAP ELF_C_READ_MMAP
-#else
-# define LIBBPF_ELF_C_READ_MMAP ELF_C_READ
-#endif
-
static inline __u64 ptr_to_u64(const void *ptr)
{
return (__u64) (unsigned long) ptr;
@@ -1064,6 +1058,11 @@ static void bpf_object__elf_finish(struct bpf_object *obj)
obj->efile.obj_buf_sz = 0;
}
+/* if libelf is old and doesn't support mmap(), fall back to read() */
+#ifndef ELF_C_READ_MMAP
+#define ELF_C_READ_MMAP ELF_C_READ
+#endif
+
static int bpf_object__elf_init(struct bpf_object *obj)
{
int err = 0;
@@ -1092,8 +1091,7 @@ static int bpf_object__elf_init(struct bpf_object *obj)
return err;
}
- obj->efile.elf = elf_begin(obj->efile.fd,
- LIBBPF_ELF_C_READ_MMAP, NULL);
+ obj->efile.elf = elf_begin(obj->efile.fd, ELF_C_READ_MMAP, NULL);
}
if (!obj->efile.elf) {