- Support instruction latency in 'perf report', with both memory latency
(weight) and instruction latency information, users can locate expensive load
instructions and understand time spent in different stages.
- Extend 'perf c2c' to display the number of loads which were blocked by data
or address conflict.
- Add 'perf stat' support for L2 topdown events in systems such as Intel's
Sapphire rapids server.
- Add support for PERF_SAMPLE_CODE_PAGE_SIZE in various tools, as a sort key, for instance:
perf report --stdio --sort=comm,symbol,code_page_size
- New 'perf daemon' command to run long running sessions while providing a way to control
the enablement of events without restarting a traditional 'perf record' session.
- Enable counting events for BPF programs in 'perf stat' just like for other
targets (tid, cgroup, cpu, etc), e.g.:
# perf stat -e ref-cycles,cycles -b 254 -I 1000
1.487903822 115,200 ref-cycles
1.487903822 86,012 cycles
2.489147029 80,560 ref-cycles
2.489147029 73,784 cycles
^C#
The example above counts 'cycles' and 'ref-cycles' of BPF program of id 254.
It is similar to bpftool-prog-profile command, but more flexible.
- Support the new layout for PERF_RECORD_MMAP2 to carry the DSO build-id using infrastructure
generalised from the eBPF subsystem, removing the need for traversing the perf.data file
to collect build-ids at the end of 'perf record' sessions and helping with long running
sessions where binaries can get replaced in updates, leading to possible mis-resolution
of symbols.
- Support filtering by hex address in 'perf script'.
- Support DSO filter in 'perf script', like in other perf tools.
- Add namespaces support to 'perf inject'
- Add support for SDT (Dtrace Style Markers) events on ARM64.
perf record:
- Fix handling of eventfd() when draining a buffer in 'perf record'.
- Improvements to the generation of metadata events for pre-existing threads (mmaps, comm, etc),
speeding up the work done at the start of system wide or per CPU 'perf record' sessions.
Hardware tracing:
- Initial support for tracing KVM with Intel PT.
- Intel PT fixes for IPC
- Support Intel PT PSB (synchronization packets) events.
- Automatically group aux-output events to overcome --filter syntax.
- Enable PERF_SAMPLE_DATA_SRC on ARMs SPE.
- Update ARM's CoreSight hardware tracing OpenCSD library to v1.0.0.
perf annotate TUI:
- Fix handling of 'k' ("show line number") hotkey
- Fix jump parsing for C++ code.
perf probe:
- Add protection to avoid endless loop.
cgroups:
- Avoid reading cgroup mountpoint multiple times, caching it.
- Fix handling of cgroup v1/v2 in mixed hierarchy.
Symbol resolving:
- Add OCaml symbol demangling.
- Further fixes for handling PE executables when using perf with Wine and .exe/.dll files.
- Fix 'perf unwind' DSO handling.
- Resolve symbols against debug file first, to deal with artifacts related to LTO.
- Fix gap between kernel end and module start on powerpc.
Reporting tools:
- The DSO filter shouldn't show samples in unresolved maps.
- Improve debuginfod support in various tools.
build ids:
- Fix 16-byte build ids in 'perf buildid-cache', add a 'perf test' entry for that case.
perf test:
- Support for PERF_SAMPLE_WEIGHT_STRUCT.
- Add test case for PERF_SAMPLE_CODE_PAGE_SIZE.
- Shell based tests for 'perf daemon's commands ('start', 'stop, 'reconfig', 'list', etc).
- ARM cs-etm 'perf test' fixes.
- Add parse-metric memory bandwidth testcase.
Compiler related:
- Fix 'perf probe' kretprobe issue caused by gcc 11 bug when used with -fpatchable-function-entry.
- Fix ARM64 build with gcc 11's -Wformat-overflow.
- Fix unaligned access in sample parsing test.
- Fix printf conversion specifier for IP addresses on arm64, s390 and powerpc.
Arch specific:
- Support exposing Performance Monitor Counter SPRs as part of extended regs on powerpc.
- Add JSON 'perf stat' metrics for ARM64's imx8mp, imx8mq and imx8mn DDR, fix imx8mm ones.
- Fix common and uarch events for ARM64's A76 and Ampere eMag
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v5.12-2020-02-19' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tool updates from Arnaldo Carvalho de Melo:
"New features:
- Support instruction latency in 'perf report', with both memory
latency (weight) and instruction latency information, users can
locate expensive load instructions and understand time spent in
different stages.
- Extend 'perf c2c' to display the number of loads which were blocked
by data or address conflict.
- Add 'perf stat' support for L2 topdown events in systems such as
Intel's Sapphire rapids server.
- Add support for PERF_SAMPLE_CODE_PAGE_SIZE in various tools, as a
sort key, for instance:
perf report --stdio --sort=comm,symbol,code_page_size
- New 'perf daemon' command to run long running sessions while
providing a way to control the enablement of events without
restarting a traditional 'perf record' session.
- Enable counting events for BPF programs in 'perf stat' just like
for other targets (tid, cgroup, cpu, etc), e.g.:
# perf stat -e ref-cycles,cycles -b 254 -I 1000
1.487903822 115,200 ref-cycles
1.487903822 86,012 cycles
2.489147029 80,560 ref-cycles
2.489147029 73,784 cycles
^C
The example above counts 'cycles' and 'ref-cycles' of BPF program
of id 254. It is similar to bpftool-prog-profile command, but more
flexible.
- Support the new layout for PERF_RECORD_MMAP2 to carry the DSO
build-id using infrastructure generalised from the eBPF subsystem,
removing the need for traversing the perf.data file to collect
build-ids at the end of 'perf record' sessions and helping with
long running sessions where binaries can get replaced in updates,
leading to possible mis-resolution of symbols.
- Support filtering by hex address in 'perf script'.
- Support DSO filter in 'perf script', like in other perf tools.
- Add namespaces support to 'perf inject'
- Add support for SDT (Dtrace Style Markers) events on ARM64.
perf record:
- Fix handling of eventfd() when draining a buffer in 'perf record'.
- Improvements to the generation of metadata events for pre-existing
threads (mmaps, comm, etc), speeding up the work done at the start
of system wide or per CPU 'perf record' sessions.
Hardware tracing:
- Initial support for tracing KVM with Intel PT.
- Intel PT fixes for IPC
- Support Intel PT PSB (synchronization packets) events.
- Automatically group aux-output events to overcome --filter syntax.
- Enable PERF_SAMPLE_DATA_SRC on ARMs SPE.
- Update ARM's CoreSight hardware tracing OpenCSD library to v1.0.0.
perf annotate TUI:
- Fix handling of 'k' ("show line number") hotkey
- Fix jump parsing for C++ code.
perf probe:
- Add protection to avoid endless loop.
cgroups:
- Avoid reading cgroup mountpoint multiple times, caching it.
- Fix handling of cgroup v1/v2 in mixed hierarchy.
Symbol resolving:
- Add OCaml symbol demangling.
- Further fixes for handling PE executables when using perf with Wine
and .exe/.dll files.
- Fix 'perf unwind' DSO handling.
- Resolve symbols against debug file first, to deal with artifacts
related to LTO.
- Fix gap between kernel end and module start on powerpc.
Reporting tools:
- The DSO filter shouldn't show samples in unresolved maps.
- Improve debuginfod support in various tools.
build ids:
- Fix 16-byte build ids in 'perf buildid-cache', add a 'perf test'
entry for that case.
perf test:
- Support for PERF_SAMPLE_WEIGHT_STRUCT.
- Add test case for PERF_SAMPLE_CODE_PAGE_SIZE.
- Shell based tests for 'perf daemon's commands ('start', 'stop,
'reconfig', 'list', etc).
- ARM cs-etm 'perf test' fixes.
- Add parse-metric memory bandwidth testcase.
Compiler related:
- Fix 'perf probe' kretprobe issue caused by gcc 11 bug when used
with -fpatchable-function-entry.
- Fix ARM64 build with gcc 11's -Wformat-overflow.
- Fix unaligned access in sample parsing test.
- Fix printf conversion specifier for IP addresses on arm64, s390 and
powerpc.
Arch specific:
- Support exposing Performance Monitor Counter SPRs as part of
extended regs on powerpc.
- Add JSON 'perf stat' metrics for ARM64's imx8mp, imx8mq and imx8mn
DDR, fix imx8mm ones.
- Fix common and uarch events for ARM64's A76 and Ampere eMag"
* tag 'perf-tools-for-v5.12-2020-02-19' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (148 commits)
perf buildid-cache: Don't skip 16-byte build-ids
perf buildid-cache: Add test for 16-byte build-id
perf symbol: Remove redundant libbfd checks
perf test: Output the sub testing result in cs-etm
perf test: Suppress logs in cs-etm testing
perf tools: Fix arm64 build error with gcc-11
perf intel-pt: Add documentation for tracing virtual machines
perf intel-pt: Split VM-Entry and VM-Exit branches
perf intel-pt: Adjust sample flags for VM-Exit
perf intel-pt: Allow for a guest kernel address filter
perf intel-pt: Support decoding of guest kernel
perf machine: Factor out machine__idle_thread()
perf machine: Factor out machines__find_guest()
perf intel-pt: Amend decoder to track the NR flag
perf intel-pt: Retain the last PIP packet payload as is
perf intel_pt: Add vmlaunch and vmresume as branches
perf script: Add branch types for VM-Entry and VM-Exit
perf auxtrace: Automatically group aux-output events
perf test: Fix unaligned access in sample parsing test
perf tools: Support arch specific PERF_SAMPLE_WEIGHT_STRUCT processing
...
Add per-program counter for number of times recursion prevention mechanism
was triggered and expose it via show_fdinfo and bpf_prog_info.
Teach bpftool to print it.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-7-alexei.starovoitov@gmail.com
When dealing with BPF/BTF/pahole and DWARF v5 I wanted to build bpftool.
While looking into the source code I found duplicate assignments in misc tools
for the LLVM eco system, e.g. clang and llvm-objcopy.
Move the Clang, LLC and/or LLVM utils definitions to tools/scripts/Makefile.include
file and add missing includes where needed. Honestly, I was inspired by the commit
c8a950d0d3 ("tools: Factor HOSTCC, HOSTLD, HOSTAR definitions").
I tested with bpftool and perf on Debian/testing AMD64 and LLVM/Clang v11.1.0-rc1.
Build instructions:
[ make and make-options ]
MAKE="make V=1"
MAKE_OPTS="HOSTCC=clang HOSTCXX=clang++ HOSTLD=ld.lld CC=clang LD=ld.lld LLVM=1 LLVM_IAS=1"
MAKE_OPTS="$MAKE_OPTS PAHOLE=/opt/pahole/bin/pahole"
[ clean-up ]
$MAKE $MAKE_OPTS -C tools/ clean
[ bpftool ]
$MAKE $MAKE_OPTS -C tools/bpf/bpftool/
[ perf ]
PYTHON=python3 $MAKE $MAKE_OPTS -C tools/perf/
I was careful with respecting the user's wish to override custom compiler, linker,
GNU/binutils and/or LLVM utils settings.
Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com> # tools/build and tools/perf
Link: https://lore.kernel.org/bpf/20210128015117.20515-1-sedat.dilek@gmail.com
This target is used to only build the bootstrap bpftool, which will be
used to generate bpf skeletons for other tools, like perf.
Signed-off-by: Song Liu <songliubraving@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Link: http://lore.kernel.org/lkml/20201228174054.907740-2-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
No additional warnings are generated by enabling this, but having it
enabled will help avoid regressions.
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210113223609.3358812-2-irogers@google.com
For older glibc ~2.17, #include'ing both linux/if.h and net/if.h
fails due to complaints about redefinition of interface flags:
CC net.o
In file included from net.c:13:0:
/usr/include/linux/if.h:71:2: error: redeclaration of enumerator ‘IFF_UP’
IFF_UP = 1<<0, /* sysfs */
^
/usr/include/net/if.h:44:5: note: previous definition of ‘IFF_UP’ was here
IFF_UP = 0x1, /* Interface is up. */
The issue was fixed in kernel headers in [1], but since compilation
of net.c picks up system headers the problem can recur.
Dropping #include <linux/if.h> resolves the issue and it is
not needed for compilation anyhow.
[1] https://lore.kernel.org/netdev/1461512707-23058-1-git-send-email-mikko.rapeli__34748.27880641$1462831734$gmane$org@iki.fi/
Fixes: f6f3bac08f ("tools/bpf: bpftool: add net support")
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/1609948746-15369-1-git-send-email-alan.maguire@oracle.com
xdp_return_frame_bulk() needs to pass a xdp_buff
to __xdp_return().
strlcpy got converted to strscpy but here it makes no
functional difference, so just keep the right code.
Conflicts:
net/netfilter/nf_tables_api.c
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In case of having so many PID results that they don't fit into a singe page
(4096) bytes, bpftool will erroneously conclude that it got corrupted data due
to 4096 not being a multiple of struct pid_iter_entry, so the last entry will
be partially truncated. Fix this by sizing the buffer to fit exactly N entries
with no truncation in the middle of record.
Fixes: d53dee3fe0 ("tools/bpftool: Show info for processes holding BPF map/prog/link/btf FDs")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20201204232002.3589803-1-andrii@kernel.org
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-12-03
The main changes are:
1) Support BTF in kernel modules, from Andrii.
2) Introduce preferred busy-polling, from Björn.
3) bpf_ima_inode_hash() and bpf_bprm_opts_set() helpers, from KP Singh.
4) Memcg-based memory accounting for bpf objects, from Roman.
5) Allow bpf_{s,g}etsockopt from cgroup bind{4,6} hooks, from Stanislav.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (118 commits)
selftests/bpf: Fix invalid use of strncat in test_sockmap
libbpf: Use memcpy instead of strncpy to please GCC
selftests/bpf: Add fentry/fexit/fmod_ret selftest for kernel module
selftests/bpf: Add tp_btf CO-RE reloc test for modules
libbpf: Support attachment of BPF tracing programs to kernel modules
libbpf: Factor out low-level BPF program loading helper
bpf: Allow to specify kernel module BTFs when attaching BPF programs
bpf: Remove hard-coded btf_vmlinux assumption from BPF verifier
selftests/bpf: Add CO-RE relocs selftest relying on kernel module BTF
selftests/bpf: Add support for marking sub-tests as skipped
selftests/bpf: Add bpf_testmod kernel module for testing
libbpf: Add kernel module BTF support for CO-RE relocations
libbpf: Refactor CO-RE relocs to not assume a single BTF object
libbpf: Add internal helper to load BTF data by FD
bpf: Keep module's btf_data_size intact after load
bpf: Fix bpf_put_raw_tracepoint()'s use of __module_address()
selftests/bpf: Add Userspace tests for TCP_WINDOW_CLAMP
bpf: Adds support for setting window clamp
samples/bpf: Fix spelling mistake "recieving" -> "receiving"
bpf: Fix cold build of test_progs-no_alu32
...
====================
Link: https://lore.kernel.org/r/20201204021936.85653-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In case of working with module's split BTF from /sys/kernel/btf/*,
auto-substitute /sys/kernel/btf/vmlinux as the base BTF. This makes using
bpftool with module BTFs faster and simpler.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201202065244.530571-4-andrii@kernel.org
For consistency of output, emit "name <anon>" for BTFs without the name. This
keeps output more consistent and obvious.
Suggested-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201202065244.530571-2-andrii@kernel.org
An appropriate return value should be set on the failed path.
Fixes: 4d374ba0bf ("tools: bpftool: implement "bpftool btf show|list"")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20201124104100.491-1-thunder.leizhen@huawei.com
Commit 47c09d6a9f67("bpftool: Introduce "prog profile" command")
introduced "bpftool prog profile" command which can be used
to profile bpf program with metrics like # of instructions,
This patch added support for itlb_misses and dtlb_misses.
During an internal bpf program performance evaluation,
I found these two metrics are also very useful. The following
is an example output:
$ bpftool prog profile id 324 duration 3 cycles itlb_misses
1885029 run_cnt
5134686073 cycles
306893 itlb_misses
$ bpftool prog profile id 324 duration 3 cycles dtlb_misses
1827382 run_cnt
4943593648 cycles
5975636 dtlb_misses
$ bpftool prog profile id 324 duration 3 cycles llc_misses
1836527 run_cnt
5019612972 cycles
4161041 llc_misses
From the above, we can see quite some dtlb misses, 3 dtlb misses
perf prog run. This might be something worth further investigation.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201119073039.4060095-1-yhs@fb.com
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-11-14
1) Add BTF generation for kernel modules and extend BTF infra in kernel
e.g. support for split BTF loading and validation, from Andrii Nakryiko.
2) Support for pointers beyond pkt_end to recognize LLVM generated patterns
on inlined branch conditions, from Alexei Starovoitov.
3) Implements bpf_local_storage for task_struct for BPF LSM, from KP Singh.
4) Enable FENTRY/FEXIT/RAW_TP tracing program to use the bpf_sk_storage
infra, from Martin KaFai Lau.
5) Add XDP bulk APIs that introduce a defer/flush mechanism to optimize the
XDP_REDIRECT path, from Lorenzo Bianconi.
6) Fix a potential (although rather theoretical) deadlock of hashtab in NMI
context, from Song Liu.
7) Fixes for cross and out-of-tree build of bpftool and runqslower allowing build
for different target archs on same source tree, from Jean-Philippe Brucker.
8) Fix error path in htab_map_alloc() triggered from syzbot, from Eric Dumazet.
9) Move functionality from test_tcpbpf_user into the test_progs framework so it
can run in BPF CI, from Alexander Duyck.
10) Lift hashtab key_size limit to be larger than MAX_BPF_STACK, from Florian Lehner.
Note that for the fix from Song we have seen a sparse report on context
imbalance which requires changes in sparse itself for proper annotation
detection where this is currently being discussed on linux-sparse among
developers [0]. Once we have more clarification/guidance after their fix,
Song will follow-up.
[0] https://lore.kernel.org/linux-sparse/CAHk-=wh4bx8A8dHnX612MsDO13st6uzAz1mJ1PaHHVevJx_ZCw@mail.gmail.com/T/https://lore.kernel.org/linux-sparse/20201109221345.uklbp3lzgq6g42zb@ltop.local/T/
* git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (66 commits)
net: mlx5: Add xdp tx return bulking support
net: mvpp2: Add xdp tx return bulking support
net: mvneta: Add xdp tx return bulking support
net: page_pool: Add bulk support for ptr_ring
net: xdp: Introduce bulking for xdp tx return path
bpf: Expose bpf_d_path helper to sleepable LSM hooks
bpf: Augment the set of sleepable LSM hooks
bpf: selftest: Use bpf_sk_storage in FENTRY/FEXIT/RAW_TP
bpf: Allow using bpf_sk_storage in FENTRY/FEXIT/RAW_TP
bpf: Rename some functions in bpf_sk_storage
bpf: Folding omem_charge() into sk_storage_charge()
selftests/bpf: Add asm tests for pkt vs pkt_end comparison.
selftests/bpf: Add skb_pkt_end test
bpf: Support for pointers beyond pkt_end.
tools/bpf: Always run the *-clean recipes
tools/bpf: Add bootstrap/ to .gitignore
bpf: Fix NULL dereference in bpf_task_storage
tools/bpftool: Fix build slowdown
tools/runqslower: Build bpftool using HOSTCC
tools/runqslower: Enable out-of-tree build
...
====================
Link: https://lore.kernel.org/r/20201114020819.29584-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
progfd is created by prog_parse_fd() in do_attach() and before the latter
returns in case of success, the file descriptor should be closed.
Fixes: 04949ccc27 ("tools: bpftool: add net attach command to attach XDP on interface")
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20201113115152.53178-1-wanghai38@huawei.com
Make $(LIBBPF)-clean and $(LIBBPF_BOOTSTRAP)-clean .PHONY targets, in
case those files exist. And keep consistency within the Makefile by
making the directory dependencies order-only.
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201112091049.3159055-2-jean-philippe@linaro.org
Commit ba2fd563b7 ("tools/bpftool: Support passing BPFTOOL_VERSION to
make") changed BPFTOOL_VERSION to a recursively expanded variable,
forcing it to be recomputed on every expansion of CFLAGS and
dramatically slowing down the bpftool build. Restore BPFTOOL_VERSION as
a simply expanded variable, guarded by an ifeq().
Fixes: ba2fd563b7 ("tools/bpftool: Support passing BPFTOOL_VERSION to make")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201110164310.2600671-8-jean-philippe@linaro.org
The bpftool build first creates an intermediate binary, executed on the
host, to generate skeletons required by the final build. When
cross-building bpftool for an architecture different from the host, the
intermediate binary should be built using the host compiler (gcc) and
the final bpftool using the cross compiler (e.g. aarch64-linux-gnu-gcc).
Generate the intermediate objects into the bootstrap/ directory using
the host toolchain.
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201110164310.2600671-4-jean-philippe@linaro.org
Cleaning a partial build can fail if the output directory for libbpf
wasn't created:
$ make -C tools/bpf/bpftool O=/tmp/bpf clean
/bin/sh: line 0: cd: /tmp/bpf/libbpf/: No such file or directory
tools/scripts/Makefile.include:17: *** output directory "/tmp/bpf/libbpf/" does not exist. Stop.
make: *** [Makefile:36: /tmp/bpf/libbpf/libbpf.a-clean] Error 2
As a result make never gets around to clearing the leftover objects. Add
the libbpf output directory as clean dependency to ensure clean always
succeeds (similarly to the "descend" macro). The directory is later
removed by the clean recipe.
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201110164310.2600671-3-jean-philippe@linaro.org
Display vmlinux BTF name and kernel module names when listing available BTFs
on the system.
In human-readable output mode, module BTFs are reported with "name
[module-name]", while vmlinux BTF will be reported as "name [vmlinux]".
Square brackets are added by bpftool and follow kernel convention when
displaying modules in human-readable text outputs.
[vmuser@archvm bpf]$ sudo ../../../bpf/bpftool/bpftool btf s
1: name [vmlinux] size 4082281B
6: size 2365B prog_ids 8,6 map_ids 3
7: name [button] size 46895B
8: name [pcspkr] size 42328B
9: name [serio_raw] size 39375B
10: name [floppy] size 57185B
11: name [i2c_core] size 76186B
12: name [crc32c_intel] size 16036B
13: name [i2c_piix4] size 50497B
14: name [irqbypass] size 14124B
15: name [kvm] size 197985B
16: name [kvm_intel] size 123564B
17: name [cryptd] size 42466B
18: name [crypto_simd] size 17187B
19: name [glue_helper] size 39205B
20: name [aesni_intel] size 41034B
25: size 36150B
pids bpftool(2519)
In JSON mode, two fields (boolean "kernel" and string "name") are reported for
each BTF object. vmlinux BTF is reported with name "vmlinux" (kernel itself
returns and empty name for vmlinux BTF).
[vmuser@archvm bpf]$ sudo ../../../bpf/bpftool/bpftool btf s -jp
[{
"id": 1,
"size": 4082281,
"prog_ids": [],
"map_ids": [],
"kernel": true,
"name": "vmlinux"
},{
"id": 6,
"size": 2365,
"prog_ids": [8,6
],
"map_ids": [3
],
"kernel": false
},{
"id": 7,
"size": 46895,
"prog_ids": [],
"map_ids": [],
"kernel": true,
"name": "button"
},{
...
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20201110011932.3201430-6-andrii@kernel.org
Updates the binary to handle the BPF_MAP_TYPE_TASK_STORAGE as
"task_storage" for printing and parsing. Also updates the documentation
and bash completion
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-5-kpsingh@chromium.org
Add ability to work with split BTF by providing extra -B flag, which allows to
specify the path to the base BTF file.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105043402.2530976-12-andrii@kernel.org
My earlier patch to reject non-zero arguments to flow dissector attach
broke attaching via bpftool. Instead of 0 it uses -1 for target_fd.
Fix this by passing a zero argument when attaching the flow dissector.
Fixes: 1b514239e8 ("bpf: flow_dissector: Check value of unused flags to BPF_PROG_ATTACH")
Reported-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201105115230.296657-1-lmb@cloudflare.com
The bpf_caps array is shorter without CAP_BPF, avoid out of bounds reads
if this isn't defined. Working around this avoids -Wno-array-bounds with
clang.
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201027233646.3434896-1-irogers@google.com
Rejecting non-native endian BTF overlapped with the addition
of support for it.
The rest were more simple overlapping changes, except the
renesas ravb binding update, which had to follow a file
move as well as a YAML conversion.
Signed-off-by: David S. Miller <davem@davemloft.net>
This change facilitates out-of-tree builds, packaging, and versioning for
test and debug purposes. Defining BPFTOOL_VERSION allows self-contained
builds within the tools tree, since it avoids use of the 'kernelversion'
target in the top-level makefile, which would otherwise pull in several
other includes from outside the tools tree.
Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200917115833.1235518-1-Tony.Ambardar@gmail.com
Dump metadata in the 'bpftool prog' list if it's present.
For some formatting some BTF code is put directly in the
metadata dumping. Sanity checks on the map and the kind of the btf_type
to make sure we are actually dumping what we are expecting.
A helper jsonw_reset is added to json writer so we can reuse the same
json writer without having extraneous commas.
Sample output:
$ bpftool prog
6: cgroup_skb name prog tag bcf7977d3b93787c gpl
[...]
btf_id 4
metadata:
a = "foo"
b = 1
$ bpftool prog --json --pretty
[{
"id": 6,
[...]
"btf_id": 4,
"metadata": {
"a": "foo",
"b": 1
}
}
]
Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: YiFei Zhu <zhuyifei1999@gmail.com>
Link: https://lore.kernel.org/bpf/20200915234543.3220146-5-sdf@google.com
When building bpf selftests like
make -C tools/testing/selftests/bpf -j20
I hit the following errors:
...
GEN /net-next/tools/testing/selftests/bpf/tools/build/bpftool/Documentation/bpftool-gen.8
<stdin>:75: (WARNING/2) Block quote ends without a blank line; unexpected unindent.
<stdin>:71: (WARNING/2) Literal block ends without a blank line; unexpected unindent.
<stdin>:85: (WARNING/2) Literal block ends without a blank line; unexpected unindent.
<stdin>:57: (WARNING/2) Block quote ends without a blank line; unexpected unindent.
<stdin>:66: (WARNING/2) Literal block ends without a blank line; unexpected unindent.
<stdin>:109: (WARNING/2) Literal block ends without a blank line; unexpected unindent.
<stdin>:175: (WARNING/2) Literal block ends without a blank line; unexpected unindent.
<stdin>:273: (WARNING/2) Literal block ends without a blank line; unexpected unindent.
make[1]: *** [/net-next/tools/testing/selftests/bpf/tools/build/bpftool/Documentation/bpftool-perf.8] Error 12
make[1]: *** Waiting for unfinished jobs....
make[1]: *** [/net-next/tools/testing/selftests/bpf/tools/build/bpftool/Documentation/bpftool-iter.8] Error 12
make[1]: *** [/net-next/tools/testing/selftests/bpf/tools/build/bpftool/Documentation/bpftool-struct_ops.8] Error 12
...
I am using:
-bash-4.4$ rst2man --version
rst2man (Docutils 0.11 [repository], Python 2.7.5, on linux2)
-bash-4.4$
The Makefile generated final .rst file (e.g., bpftool-cgroup.rst) looks like
...
ID AttachType AttachFlags Name
\n SEE ALSO\n========\n\t**bpf**\ (2),\n\t**bpf-helpers**\
(7),\n\t**bpftool**\ (8),\n\t**bpftool-btf**\
(8),\n\t**bpftool-feature**\ (8),\n\t**bpftool-gen**\
(8),\n\t**bpftool-iter**\ (8),\n\t**bpftool-link**\
(8),\n\t**bpftool-map**\ (8),\n\t**bpftool-net**\
(8),\n\t**bpftool-perf**\ (8),\n\t**bpftool-prog**\
(8),\n\t**bpftool-struct_ops**\ (8)\n
The rst2man generated .8 file looks like
Literal block ends without a blank line; unexpected unindent.
.sp
n SEEALSOn========nt**bpf**(2),nt**bpf\-helpers**(7),nt**bpftool**(8),nt**bpftool\-btf**(8),nt**
bpftool\-feature**(8),nt**bpftool\-gen**(8),nt**bpftool\-iter**(8),nt**bpftool\-link**(8),nt**
bpftool\-map**(8),nt**bpftool\-net**(8),nt**bpftool\-perf**(8),nt**bpftool\-prog**(8),nt**
bpftool\-struct_ops**(8)n
Looks like that particular version of rst2man prefers to have actual new line
instead of \n.
Since `echo -e` may not be available in some environment, let us use `printf`.
Format string "%b" is used for `printf` to ensure all escape characters are
interpretted properly.
Fixes: 18841da981 ("tools: bpftool: Automate generation for "SEE ALSO" sections in man pages")
Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Cc: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200914183110.999906-1-yhs@fb.com
The "SEE ALSO" sections of bpftool's manual pages refer to bpf(2),
bpf-helpers(7), then all existing bpftool man pages (save the current
one).
This leads to nearly-identical lists being duplicated in all manual
pages. Ideally, when a new page is created, all lists should be updated
accordingly, but this has led to omissions and inconsistencies multiple
times in the past.
Let's take it out of the RST files and generate the "SEE ALSO" sections
automatically in the Makefile when generating the man pages. The lists
are not really useful in the RST anyway because all other pages are
available in the same directory.
v3:
- Fix conflict with a previous patchset that introduced RST2MAN_OPTS
variable passed to rst2man.
v2:
- Use "echo -n" instead of "printf" in Makefile, to avoid any risk of
passing a format string directly to the command.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200910203935.25304-1-quentin@isovalent.com
There is no support for creating maps of types array-of-map or
hash-of-map in bpftool. This is because the kernel needs an inner_map_fd
to collect metadata on the inner maps to be supported by the new map,
but bpftool does not provide a way to pass this file descriptor.
Add a new optional "inner_map" keyword that can be used to pass a
reference to a map, retrieve a fd to that map, and pass it as the
inner_map_fd.
Add related documentation and bash completion. Note that we can
reference the inner map by its name, meaning we can have several times
the keyword "name" with different meanings (mandatory outer map name,
and possibly a name to use to find the inner_map_fd). The bash
completion will offer it just once, and will not suggest "name" on the
following command:
# bpftool map create /sys/fs/bpf/my_outer_map type hash_of_maps \
inner_map name my_inner_map [TAB]
Fixing that specific case seems too convoluted. Completion will work as
expected, however, if the outer map name comes first and the "inner_map
name ..." is passed second.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200910102652.10509-4-quentin@isovalent.com
When dumping outer maps or prog_array maps, and on lookup failure,
bpftool simply skips the entry with no error message. This is because
the kernel returns non-zero when no value is found for the provided key,
which frequently happen for those maps if they have not been filled.
When such a case occurs, errno is set to ENOENT. It seems unlikely we
could receive other error codes at this stage (we successfully retrieved
map info just before), but to be on the safe side, let's skip the entry
only if errno was ENOENT, and not for the other errors.
v3: New patch
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200910102652.10509-3-quentin@isovalent.com
The function used to dump a map entry in bpftool is a bit difficult to
follow, as a consequence to earlier refactorings. There is a variable
("num_elems") which does not appear to be necessary, and the error
handling would look cleaner if moved to its own function. Let's clean it
up. No functional change.
v2:
- v1 was erroneously removing the check on fd maps in an attempt to get
support for outer map dumps. This is already working. Instead, v2
focuses on cleaning up the dump_map_elem() function, to avoid
similar confusion in the future.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200910102652.10509-2-quentin@isovalent.com
Nearly all man pages for bpftool have the same common set of option
flags (--help, --version, --json, --pretty, --debug). The description is
duplicated across all the pages, which is more difficult to maintain if
the description of an option changes. It may also be confusing to sort
out what options are not "common" and should not be copied when creating
new manual pages.
Let's move the description for those common options to a separate file,
which is included with a RST directive when generating the man pages.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200909162500.17010-3-quentin@isovalent.com
Bpftool has a number of features that can be included or left aside
during compilation. This includes:
- Support for libbfd, providing the disassembler for JIT-compiled
programs.
- Support for BPF skeletons, used for profiling programs or iterating on
the PIDs of processes associated with BPF objects.
In order to make it easy for users to understand what features were
compiled for a given bpftool binary, print the status of the two
features above when showing the version number for bpftool ("bpftool -V"
or "bpftool version"). Document this in the main manual page. Example
invocations:
$ bpftool version
./bpftool v5.9.0-rc1
features: libbfd, skeletons
$ bpftool -p version
{
"version": "5.9.0-rc1",
"features": {
"libbfd": true,
"skeletons": true
}
}
Some other parameters are optional at compilation
("DISASM_FOUR_ARGS_SIGNATURE", LIBCAP support) but they do not impact
significantly bpftool's behaviour from a user's point of view, so their
status is not reported.
Available commands and supported program types depend on the version
number, and are therefore not reported either. Note that they are
already available, albeit without JSON, via bpftool's help messages.
v3:
- Use a simple list instead of boolean values for plain output.
v2:
- Fix JSON (object instead or array for the features).
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200909162500.17010-2-quentin@isovalent.com
To build man pages for bpftool (and for eBPF helper functions), rst2man
can log different levels of information. Let's make it log all levels
to keep the RST files clean.
Doing so, rst2man complains about double colons, used for literal
blocks, that look like underlines for section titles. Let's add the
necessary blank lines.
v2:
- Use "--verbose" instead of "-r 1" (same behaviour but more readable).
- Pass it through a RST2MAN_OPTS variable so we can easily pass other
options too.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200909162251.15498-2-quentin@isovalent.com
Fix a formatting error in the documentation for bpftool-link, so that
the man page can build correctly.
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200904161454.31135-2-quentin@isovalent.com
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-09-01
The following pull-request contains BPF updates for your *net-next* tree.
There are two small conflicts when pulling, resolve as follows:
1) Merge conflict in tools/lib/bpf/libbpf.c between 88a8212028 ("libbpf: Factor
out common ELF operations and improve logging") in bpf-next and 1e891e513e
("libbpf: Fix map index used in error message") in net-next. Resolve by taking
the hunk in bpf-next:
[...]
scn = elf_sec_by_idx(obj, obj->efile.btf_maps_shndx);
data = elf_sec_data(obj, scn);
if (!scn || !data) {
pr_warn("elf: failed to get %s map definitions for %s\n",
MAPS_ELF_SEC, obj->path);
return -EINVAL;
}
[...]
2) Merge conflict in drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c between
9647c57b11 ("xsk: i40e: ice: ixgbe: mlx5: Test for dma_need_sync earlier for
better performance") in bpf-next and e20f0dbf20 ("net/mlx5e: RX, Add a prefetch
command for small L1_CACHE_BYTES") in net-next. Resolve the two locations by retaining
net_prefetch() and taking xsk_buff_dma_sync_for_cpu() from bpf-next. Should look like:
[...]
xdp_set_data_meta_invalid(xdp);
xsk_buff_dma_sync_for_cpu(xdp, rq->xsk_pool);
net_prefetch(xdp->data);
[...]
We've added 133 non-merge commits during the last 14 day(s) which contain
a total of 246 files changed, 13832 insertions(+), 3105 deletions(-).
The main changes are:
1) Initial support for sleepable BPF programs along with bpf_copy_from_user() helper
for tracing to reliably access user memory, from Alexei Starovoitov.
2) Add BPF infra for writing and parsing TCP header options, from Martin KaFai Lau.
3) bpf_d_path() helper for returning full path for given 'struct path', from Jiri Olsa.
4) AF_XDP support for shared umems between devices and queues, from Magnus Karlsson.
5) Initial prep work for full BPF-to-BPF call support in libbpf, from Andrii Nakryiko.
6) Generalize bpf_sk_storage map & add local storage for inodes, from KP Singh.
7) Implement sockmap/hash updates from BPF context, from Lorenz Bauer.
8) BPF xor verification for scalar types & add BPF link iterator, from Yonghong Song.
9) Use target's prog type for BPF_PROG_TYPE_EXT prog verification, from Udip Pant.
10) Rework BPF tracing samples to use libbpf loader, from Daniel T. Lee.
11) Fix xdpsock sample to really cycle through all buffers, from Weqaar Janjua.
12) Improve type safety for tun/veth XDP frame handling, from Maciej Żenczykowski.
13) Various smaller cleanups and improvements all over the place.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The system for "Auto-detecting system features" located under
tools/build/ are (currently) used by perf, libbpf and bpftool. It can
contain stalled feature detection files, which are not cleaned up by
libbpf and bpftool on make clean (side-note: perf tool is correct).
Fix this by making the users invoke the make clean target.
Some details about the changes. The libbpf Makefile already had a
clean-config target (which seems to be copy-pasted from perf), but this
target was not "connected" (a make dependency) to clean target. Choose
not to rename target as someone might be using it. Did change the output
from "CLEAN config" to "CLEAN feature-detect", to make it more clear
what happens.
This is related to the complaint and troubleshooting in the following
link: https://lore.kernel.org/lkml/20200818122007.2d1cfe2d@carbon/
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/lkml/20200818122007.2d1cfe2d@carbon/
Link: https://lore.kernel.org/bpf/159851841661.1072907.13770213104521805592.stgit@firesoul
Similar to bpf_local_storage for sockets, add local storage for inodes.
The life-cycle of storage is managed with the life-cycle of the inode.
i.e. the storage is destroyed along with the owning inode.
The BPF LSM allocates an __rcu pointer to the bpf_local_storage in the
security blob which are now stackable and can co-exist with other LSMs.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200825182919.1118197-6-kpsingh@chromium.org
The link query for bpf iterators is implemented.
Besides being shown to the user what bpf iterator
the link represents, the target_name is also used
to filter out what additional information should be
printed out, e.g., whether map_id should be shown or not.
The following is an example of bpf_iter link dump,
plain output or pretty output.
$ bpftool link show
11: iter prog 59 target_name task
pids test_progs(1749)
34: iter prog 173 target_name bpf_map_elem map_id 127
pids test_progs_1(1753)
$ bpftool -p link show
[{
"id": 11,
"type": "iter",
"prog_id": 59,
"target_name": "task",
"pids": [{
"pid": 1749,
"comm": "test_progs"
}
]
},{
"id": 34,
"type": "iter",
"prog_id": 173,
"target_name": "bpf_map_elem",
"map_id": 127,
"pids": [{
"pid": 1753,
"comm": "test_progs_1"
}
]
}
]
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200821184420.574430-1-yhs@fb.com
Most netlink-related functions were unique to bpftool usage, so I moved them
into net.c. Few functions are still used by both bpftool and libbpf itself
internally, so I've copy-pasted them (libbpf_nl_get_link,
libbpf_netlink_open). It's a bit of duplication of code, but better separation
of libbpf as a library with public API and bpftool, relying on unexposed
functions in libbpf.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200819013607.3607269-3-andriin@fb.com
When the error code is EAGAIN, the kernel signals the user
space should retry the read() operation for bpf iterators.
Let us do it.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200818222312.2181675-1-yhs@fb.com
The comment in the code describes this in good details. Generate such a memory
layout that would work both on 32-bit and 64-bit architectures for user-space.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200813204945.1020225-9-andriin@fb.com
Fix few compilation warnings in bpftool when compiling in 32-bit mode.
Abstract away u64 to pointer conversion into a helper function.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200813204945.1020225-2-andriin@fb.com
Linus Torvalds