Commit c9a0f3b8 authored by Jiri Olsa's avatar Jiri Olsa Committed by Alexei Starovoitov
Browse files

bpf: Resolve BTF IDs in vmlinux image 



Using BTF_ID_LIST macro to define lists for several helpers
using BTF arguments.

And running resolve_btfids on vmlinux elf object during linking,
so the .BTF_ids section gets the IDs resolved.

Signed-off-by: default avatarJiri Olsa <jolsa@kernel.org>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Tested-by: default avatarAndrii Nakryiko <andriin@fb.com>
Acked-by: default avatarAndrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-5-jolsa@kernel.org
parent 5a2798ab

Makefile

+2 −1
Original line number Diff line number Diff line
@@ -448,6 +448,7 @@ OBJSIZE = $(CROSS_COMPILE)size 
STRIP		= $(CROSS_COMPILE)strip

endif

PAHOLE		= pahole

RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids

LEX		= flex

YACC		= bison

AWK		= awk
@@ -510,7 +511,7 @@ GCC_PLUGINS_CFLAGS := 
CLANG_FLAGS :=



export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC

export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL

export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL

export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX

export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ

export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE

kernel/bpf/stackmap.c

+4 −1
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 
#include <linux/elf.h>

#include <linux/pagemap.h>

#include <linux/irq_work.h>

#include <linux/btf_ids.h>

#include "percpu_freelist.h"



#define STACK_CREATE_FLAG_MASK					\
@@ -576,7 +577,9 @@ BPF_CALL_4(bpf_get_task_stack, struct task_struct *, task, void *, buf, 
	return __bpf_get_stack(regs, task, buf, size, flags);

}



static int bpf_get_task_stack_btf_ids[5];

BTF_ID_LIST(bpf_get_task_stack_btf_ids)

BTF_ID(struct, task_struct)



const struct bpf_func_proto bpf_get_task_stack_proto = {

	.func		= bpf_get_task_stack,

	.gpl_only	= false,

kernel/trace/bpf_trace.c

+7 −2
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ 
#include <linux/kprobes.h>

#include <linux/syscalls.h>

#include <linux/error-injection.h>

#include <linux/btf_ids.h>



#include <asm/tlb.h>
@@ -710,7 +711,9 @@ out: 
	return err;

}



static int bpf_seq_printf_btf_ids[5];

BTF_ID_LIST(bpf_seq_printf_btf_ids)

BTF_ID(struct, seq_file)



static const struct bpf_func_proto bpf_seq_printf_proto = {

	.func		= bpf_seq_printf,

	.gpl_only	= true,
@@ -728,7 +731,9 @@ BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len) 
	return seq_write(m, data, len) ? -EOVERFLOW : 0;

}



static int bpf_seq_write_btf_ids[5];

BTF_ID_LIST(bpf_seq_write_btf_ids)

BTF_ID(struct, seq_file)



static const struct bpf_func_proto bpf_seq_write_proto = {

	.func		= bpf_seq_write,

	.gpl_only	= true,

net/core/filter.c

+7 −2
Original line number Diff line number Diff line
@@ -75,6 +75,7 @@ 
#include <net/ipv6_stubs.h>

#include <net/bpf_sk_storage.h>

#include <net/transp_v6.h>

#include <linux/btf_ids.h>



/**

 *	sk_filter_trim_cap - run a packet through a socket filter
@@ -3779,7 +3780,9 @@ static const struct bpf_func_proto bpf_skb_event_output_proto = { 
	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,

};



static int bpf_skb_output_btf_ids[5];

BTF_ID_LIST(bpf_skb_output_btf_ids)

BTF_ID(struct, sk_buff)



const struct bpf_func_proto bpf_skb_output_proto = {

	.func		= bpf_skb_event_output,

	.gpl_only	= true,
@@ -4173,7 +4176,9 @@ static const struct bpf_func_proto bpf_xdp_event_output_proto = { 
	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,

};



static int bpf_xdp_output_btf_ids[5];

BTF_ID_LIST(bpf_xdp_output_btf_ids)

BTF_ID(struct, xdp_buff)



const struct bpf_func_proto bpf_xdp_output_proto = {

	.func		= bpf_xdp_event_output,

	.gpl_only	= true,

scripts/link-vmlinux.sh

+6 −0
Original line number Diff line number Diff line
@@ -336,6 +336,12 @@ fi 


vmlinux_link vmlinux "${kallsymso}" ${btf_vmlinux_bin_o}



# fill in BTF IDs

if [ -n "${CONFIG_DEBUG_INFO_BTF}" ]; then

info BTFIDS vmlinux

${RESOLVE_BTFIDS} vmlinux

fi



if [ -n "${CONFIG_BUILDTIME_TABLE_SORT}" ]; then

	info SORTTAB vmlinux

	if ! sorttable vmlinux; then

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