linux/tools
Kumar Kartikeya Dwivedi 18f4fccbf3 libbpf: Update gen_loader to emit BTF_KIND_FUNC relocations
This change updates the BPF syscall loader to relocate BTF_KIND_FUNC
relocations, with support for weak kfunc relocations. The general idea
is to move map_fds to loader map, and also use the data for storing
kfunc BTF fds. Since both reuse the fd_array parameter, they need to be
kept together.

For map_fds, we reserve MAX_USED_MAPS slots in a region, and for kfunc,
we reserve MAX_KFUNC_DESCS. This is done so that insn->off has more
chances of being <= INT16_MAX than treating data map as a sparse array
and adding fd as needed.

When the MAX_KFUNC_DESCS limit is reached, we fall back to the sparse
array model, so that as long as it does remain <= INT16_MAX, we pass an
index relative to the start of fd_array.

We store all ksyms in an array where we try to avoid calling the
bpf_btf_find_by_name_kind helper, and also reuse the BTF fd that was
already stored. This also speeds up the loading process compared to
emitting calls in all cases, in later tests.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211002011757.311265-9-memxor@gmail.com
2021-10-05 17:07:42 -07:00
..
accounting
arch A set of fixes for X86: 2021-09-26 10:09:20 -07:00
bootconfig tools/bootconfig: Define memblock_free_ptr() to fix build error 2021-09-15 09:49:48 -07:00
bpf tools: Allow specifying base BTF file in resolve_btfids 2021-10-05 17:07:41 -07:00
build perf cs-etm: Update OpenCSD decoder for ETE 2021-09-03 08:16:00 -03:00
cgroup
debugging
edid
firewire
firmware
gpio
hv
iio
include bpf: Clarify data_len param in bpf_snprintf and bpf_seq_printf comments 2021-09-17 14:02:06 -07:00
io_uring tools/io_uring/io_uring-cp: sync with liburing example 2021-08-13 08:58:11 -06:00
kvm/kvm_stat
laptop
leds
lib libbpf: Update gen_loader to emit BTF_KIND_FUNC relocations 2021-10-05 17:07:42 -07:00
memory-model tools/memory-model: Document data_race(READ_ONCE()) 2021-07-27 11:48:55 -07:00
objtool
pci tools: PCI: Zero-initialize param 2021-08-05 11:01:30 +01:00
pcmcia
perf perf iostat: Fix Segmentation fault from NULL 'struct perf_counts_values *' 2021-09-27 09:41:07 -03:00
power
rcu
scripts
spi
testing tools: Allow specifying base BTF file in resolve_btfids 2021-10-05 17:07:41 -07:00
thermal/tmon tools/thermal/tmon: Add cross compiling support 2021-08-14 15:33:19 +02:00
time
tracing
usb usb: testusb: Fix for showing the connection speed 2021-09-14 10:31:41 +02:00
virtio tools/virtio: fix build 2021-08-11 06:44:24 -04:00
vm tools/vm/page-types: remove dependency on opt_file for idle page tracking 2021-09-24 16:13:35 -07:00
wmi
Makefile