Commit Graph

1192 Commits

Author SHA1 Message Date
Andrii Nakryiko
6803ee25f0 libbpf: Extract and generalize CPU mask parsing logic
This logic is re-used for parsing a set of online CPUs. Having it as an
isolated piece of code working with input string makes it conveninent to test
this logic as well. While refactoring, also improve the robustness of original
implementation.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191212013548.1690564-1-andriin@fb.com
2019-12-13 12:58:51 -08:00
Jakub Sitnicki
67d69ccdf3 libbpf: Recognize SK_REUSEPORT programs from section name
Allow loading BPF object files that contain SK_REUSEPORT programs without
having to manually set the program type before load if the the section name
is set to "sk_reuseport".

Makes user-space code needed to load SK_REUSEPORT BPF program more concise.

Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191212102259.418536-2-jakub@cloudflare.com
2019-12-13 12:38:00 -08:00
Andrii Nakryiko
679152d3a3 libbpf: Fix printf compilation warnings on ppc64le arch
On ppc64le __u64 and __s64 are defined as long int and unsigned long int,
respectively. This causes compiler to emit warning when %lld/%llu are used to
printf 64-bit numbers. Fix this by casting to size_t/ssize_t with %zu and %zd
format specifiers, respectively.

v1->v2:
- use size_t/ssize_t instead of custom typedefs (Martin).

Fixes: 1f8e2bcb2c ("libbpf: Refactor relocation handling")
Fixes: abd29c9314 ("libbpf: allow specifying map definitions using BTF")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191212171918.638010-1-andriin@fb.com
2019-12-12 13:47:24 -08:00
Andrii Nakryiko
09c4708d3c libbpf: Bump libpf current version to v0.0.7
New development cycles starts, bump to v0.0.7 proactively.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191209224022.3544519-1-andriin@fb.com
2019-12-11 14:50:37 +01:00
Stanislav Fomichev
6bf6affe18 selftests/bpf: Bring back c++ include/link test
Commit 5c26f9a783 ("libbpf: Don't use cxx to test_libpf target")
converted existing c++ test to c. We still want to include and
link against libbpf from c++ code, so reinstate this test back,
this time in a form of a selftest with a clear comment about
its purpose.

v2:
* -lelf -> $(LDLIBS) (Andrii Nakryiko)

Fixes: 5c26f9a783 ("libbpf: Don't use cxx to test_libpf target")
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191202215931.248178-1-sdf@google.com
2019-12-04 17:57:55 -08:00
David S. Miller
734c7022ad Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2019-12-02

The following pull-request contains BPF updates for your *net* tree.

We've added 10 non-merge commits during the last 6 day(s) which contain
a total of 10 files changed, 60 insertions(+), 51 deletions(-).

The main changes are:

1) Fix vmlinux BTF generation for binutils pre v2.25, from Stanislav Fomichev.

2) Fix libbpf global variable relocation to take symbol's st_value offset
   into account, from Andrii Nakryiko.

3) Fix libbpf build on powerpc where check_abi target fails due to different
   readelf output format, from Aurelien Jarno.

4) Don't set BPF insns RO for the case when they are JITed in order to avoid
   fragmenting the direct map, from Daniel Borkmann.

5) Fix static checker warning in btf_distill_func_proto() as well as a build
   error due to empty enum when BPF is compiled out, from Alexei Starovoitov.

6) Fix up generation of bpf_helper_defs.h for perf, from Arnaldo Carvalho de Melo.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-02 10:50:29 -08:00
Aurelien Jarno
3464afdf11 libbpf: Fix readelf output parsing on powerpc with recent binutils
On powerpc with recent versions of binutils, readelf outputs an extra
field when dumping the symbols of an object file. For example:

    35: 0000000000000838    96 FUNC    LOCAL  DEFAULT [<localentry>: 8]     1 btf_is_struct

The extra "[<localentry>: 8]" prevents the GLOBAL_SYM_COUNT variable to
be computed correctly and causes the check_abi target to fail.

Fix that by looking for the symbol name in the last field instead of the
8th one. This way it should also cope with future extra fields.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/bpf/20191201195728.4161537-1-aurelien@aurel32.net
2019-12-02 10:31:54 +01:00
Alexei Starovoitov
7c3977d1e8 libbpf: Fix sym->st_value print on 32-bit arches
The st_value field is a 64-bit value and causing this error on 32-bit arches:

In file included from libbpf.c:52:
libbpf.c: In function 'bpf_program__record_reloc':
libbpf_internal.h:59:22: error: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'Elf64_Addr' {aka 'const long long unsigned int'} [-Werror=format=]

Fix it with (__u64) cast.

Fixes: 1f8e2bcb2c ("libbpf: Refactor relocation handling")
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-11-27 17:46:56 -08:00
Arnaldo Carvalho de Melo
1fd450f992 libbpf: Fix up generation of bpf_helper_defs.h
$ make -C tools/perf build-test

does, ends up with these two problems:

  make[3]: *** No rule to make target '/tmp/tmp.zq13cHILGB/perf-5.3.0/include/uapi/linux/bpf.h', needed by 'bpf_helper_defs.h'.  Stop.
  make[3]: *** Waiting for unfinished jobs....
  make[2]: *** [Makefile.perf:757: /tmp/tmp.zq13cHILGB/perf-5.3.0/tools/lib/bpf/libbpf.a] Error 2
  make[2]: *** Waiting for unfinished jobs....

Because $(srcdir) points to the /tmp/tmp.zq13cHILGB/perf-5.3.0 directory
and we need '/tools/ after that variable, and after fixing this then we
get to another problem:

  /bin/sh: /home/acme/git/perf/tools/scripts/bpf_helpers_doc.py: No such file or directory
  make[3]: *** [Makefile:184: bpf_helper_defs.h] Error 127
  make[3]: *** Deleting file 'bpf_helper_defs.h'
    LD       /tmp/build/perf/libapi-in.o
  make[2]: *** [Makefile.perf:778: /tmp/build/perf/libbpf.a] Error 2
  make[2]: *** Waiting for unfinished jobs....

Because this requires something outside the tools/ directories that gets
collected into perf's detached tarballs, to fix it just add it to
tools/perf/MANIFEST, which this patch does, now it works for that case
and also for all these other cases.

Fixes: e01a75c159 ("libbpf: Move bpf_{helpers, helper_defs, endian, tracing}.h into libbpf")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-4pnkg2vmdvq5u6eivc887wen@git.kernel.org
Link: https://lore.kernel.org/bpf/20191126151045.GB19483@kernel.org
2019-11-27 16:52:31 -08:00
Andrii Nakryiko
53f8dd434b libbpf: Fix global variable relocation
Similarly to a0d7da26ce ("libbpf: Fix call relocation offset calculation
bug"), relocations against global variables need to take into account
referenced symbol's st_value, which holds offset into a corresponding data
section (and, subsequently, offset into internal backing map). For static
variables this offset is always zero and data offset is completely described
by respective instruction's imm field.

Convert a bunch of selftests to global variables. Previously they were relying
on `static volatile` trick to ensure Clang doesn't inline static variables,
which with global variables is not necessary anymore.

Fixes: 393cdfbee8 ("libbpf: Support initialized global variables")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191127200651.1381348-1-andriin@fb.com
2019-11-27 16:34:21 -08:00
Andrii Nakryiko
b568405856 libbpf: Fix Makefile' libbpf symbol mismatch diagnostic
Fix Makefile's diagnostic diff output when there is LIBBPF_API-versioned
symbols mismatch.

Fixes: 1bd6352459 ("libbpf: handle symbol versioning properly for libbpf.a")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191127200134.1360660-1-andriin@fb.com
2019-11-27 22:29:02 +01:00
Linus Torvalds
168829ad09 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - A comprehensive rewrite of the robust/PI futex code's exit handling
     to fix various exit races. (Thomas Gleixner et al)

   - Rework the generic REFCOUNT_FULL implementation using
     atomic_fetch_* operations so that the performance impact of the
     cmpxchg() loops is mitigated for common refcount operations.

     With these performance improvements the generic implementation of
     refcount_t should be good enough for everybody - and this got
     confirmed by performance testing, so remove ARCH_HAS_REFCOUNT and
     REFCOUNT_FULL entirely, leaving the generic implementation enabled
     unconditionally. (Will Deacon)

   - Other misc changes, fixes, cleanups"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
  lkdtm: Remove references to CONFIG_REFCOUNT_FULL
  locking/refcount: Remove unused 'refcount_error_report()' function
  locking/refcount: Consolidate implementations of refcount_t
  locking/refcount: Consolidate REFCOUNT_{MAX,SATURATED} definitions
  locking/refcount: Move saturation warnings out of line
  locking/refcount: Improve performance of generic REFCOUNT_FULL code
  locking/refcount: Move the bulk of the REFCOUNT_FULL implementation into the <linux/refcount.h> header
  locking/refcount: Remove unused refcount_*_checked() variants
  locking/refcount: Ensure integer operands are treated as signed
  locking/refcount: Define constants for saturation and max refcount values
  futex: Prevent exit livelock
  futex: Provide distinct return value when owner is exiting
  futex: Add mutex around futex exit
  futex: Provide state handling for exec() as well
  futex: Sanitize exit state handling
  futex: Mark the begin of futex exit explicitly
  futex: Set task::futex_state to DEAD right after handling futex exit
  futex: Split futex_mm_release() for exit/exec
  exit/exec: Seperate mm_release()
  futex: Replace PF_EXITPIDONE with a state
  ...
2019-11-26 16:02:40 -08:00
Linus Torvalds
3f59dbcace Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "The main kernel side changes in this cycle were:

   - Various Intel-PT updates and optimizations (Alexander Shishkin)

   - Prohibit kprobes on Xen/KVM emulate prefixes (Masami Hiramatsu)

   - Add support for LSM and SELinux checks to control access to the
     perf syscall (Joel Fernandes)

   - Misc other changes, optimizations, fixes and cleanups - see the
     shortlog for details.

  There were numerous tooling changes as well - 254 non-merge commits.
  Here are the main changes - too many to list in detail:

   - Enhancements to core tooling infrastructure, perf.data, libperf,
     libtraceevent, event parsing, vendor events, Intel PT, callchains,
     BPF support and instruction decoding.

   - There were updates to the following tools:

        perf annotate
        perf diff
        perf inject
        perf kvm
        perf list
        perf maps
        perf parse
        perf probe
        perf record
        perf report
        perf script
        perf stat
        perf test
        perf trace

   - And a lot of other changes: please see the shortlog and Git log for
     more details"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (279 commits)
  perf parse: Fix potential memory leak when handling tracepoint errors
  perf probe: Fix spelling mistake "addrees" -> "address"
  libtraceevent: Fix memory leakage in copy_filter_type
  libtraceevent: Fix header installation
  perf intel-bts: Does not support AUX area sampling
  perf intel-pt: Add support for decoding AUX area samples
  perf intel-pt: Add support for recording AUX area samples
  perf pmu: When using default config, record which bits of config were changed by the user
  perf auxtrace: Add support for queuing AUX area samples
  perf session: Add facility to peek at all events
  perf auxtrace: Add support for dumping AUX area samples
  perf inject: Cut AUX area samples
  perf record: Add aux-sample-size config term
  perf record: Add support for AUX area sampling
  perf auxtrace: Add support for AUX area sample recording
  perf auxtrace: Move perf_evsel__find_pmu()
  perf record: Add a function to test for kernel support for AUX area sampling
  perf tools: Add kernel AUX area sampling definitions
  perf/core: Make the mlock accounting simple again
  perf report: Jump to symbol source view from total cycles view
  ...
2019-11-26 15:04:47 -08:00
Linus Torvalds
386403a115 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:
 "Another merge window, another pull full of stuff:

   1) Support alternative names for network devices, from Jiri Pirko.

   2) Introduce per-netns netdev notifiers, also from Jiri Pirko.

   3) Support MSG_PEEK in vsock/virtio, from Matias Ezequiel Vara
      Larsen.

   4) Allow compiling out the TLS TOE code, from Jakub Kicinski.

   5) Add several new tracepoints to the kTLS code, also from Jakub.

   6) Support set channels ethtool callback in ena driver, from Sameeh
      Jubran.

   7) New SCTP events SCTP_ADDR_ADDED, SCTP_ADDR_REMOVED,
      SCTP_ADDR_MADE_PRIM, and SCTP_SEND_FAILED_EVENT. From Xin Long.

   8) Add XDP support to mvneta driver, from Lorenzo Bianconi.

   9) Lots of netfilter hw offload fixes, cleanups and enhancements,
      from Pablo Neira Ayuso.

  10) PTP support for aquantia chips, from Egor Pomozov.

  11) Add UDP segmentation offload support to igb, ixgbe, and i40e. From
      Josh Hunt.

  12) Add smart nagle to tipc, from Jon Maloy.

  13) Support L2 field rewrite by TC offloads in bnxt_en, from Venkat
      Duvvuru.

  14) Add a flow mask cache to OVS, from Tonghao Zhang.

  15) Add XDP support to ice driver, from Maciej Fijalkowski.

  16) Add AF_XDP support to ice driver, from Krzysztof Kazimierczak.

  17) Support UDP GSO offload in atlantic driver, from Igor Russkikh.

  18) Support it in stmmac driver too, from Jose Abreu.

  19) Support TIPC encryption and auth, from Tuong Lien.

  20) Introduce BPF trampolines, from Alexei Starovoitov.

  21) Make page_pool API more numa friendly, from Saeed Mahameed.

  22) Introduce route hints to ipv4 and ipv6, from Paolo Abeni.

  23) Add UDP segmentation offload to cxgb4, Rahul Lakkireddy"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1857 commits)
  libbpf: Fix usage of u32 in userspace code
  mm: Implement no-MMU variant of vmalloc_user_node_flags
  slip: Fix use-after-free Read in slip_open
  net: dsa: sja1105: fix sja1105_parse_rgmii_delays()
  macvlan: schedule bc_work even if error
  enetc: add support Credit Based Shaper(CBS) for hardware offload
  net: phy: add helpers phy_(un)lock_mdio_bus
  mdio_bus: don't use managed reset-controller
  ax88179_178a: add ethtool_op_get_ts_info()
  mlxsw: spectrum_router: Fix use of uninitialized adjacency index
  mlxsw: spectrum_router: After underlay moves, demote conflicting tunnels
  bpf: Simplify __bpf_arch_text_poke poke type handling
  bpf: Introduce BPF_TRACE_x helper for the tracing tests
  bpf: Add bpf_jit_blinding_enabled for !CONFIG_BPF_JIT
  bpf, testing: Add various tail call test cases
  bpf, x86: Emit patchable direct jump as tail call
  bpf: Constant map key tracking for prog array pokes
  bpf: Add poke dependency tracking for prog array maps
  bpf: Add initial poke descriptor table for jit images
  bpf: Move owner type, jited info into array auxiliary data
  ...
2019-11-25 20:02:57 -08:00
Linus Torvalds
436b2a8039 Printk changes for 5.5
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Merge tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk

Pull printk updates from Petr Mladek:

 - Allow to print symbolic error names via new %pe modifier.

 - Use pr_warn() instead of the remaining pr_warning() calls. Fix
   formatting of the related lines.

 - Add VSPRINTF entry to MAINTAINERS.

* tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (32 commits)
  checkpatch: don't warn about new vsprintf pointer extension '%pe'
  MAINTAINERS: Add VSPRINTF
  tools lib api: Renaming pr_warning to pr_warn
  ASoC: samsung: Use pr_warn instead of pr_warning
  lib: cpu_rmap: Use pr_warn instead of pr_warning
  trace: Use pr_warn instead of pr_warning
  dma-debug: Use pr_warn instead of pr_warning
  vgacon: Use pr_warn instead of pr_warning
  fs: afs: Use pr_warn instead of pr_warning
  sh/intc: Use pr_warn instead of pr_warning
  scsi: Use pr_warn instead of pr_warning
  platform/x86: intel_oaktrail: Use pr_warn instead of pr_warning
  platform/x86: asus-laptop: Use pr_warn instead of pr_warning
  platform/x86: eeepc-laptop: Use pr_warn instead of pr_warning
  oprofile: Use pr_warn instead of pr_warning
  of: Use pr_warn instead of pr_warning
  macintosh: Use pr_warn instead of pr_warning
  idsn: Use pr_warn instead of pr_warning
  ide: Use pr_warn instead of pr_warning
  crypto: n2: Use pr_warn instead of pr_warning
  ...
2019-11-25 19:40:40 -08:00
Andrii Nakryiko
b615e5a1e0 libbpf: Fix usage of u32 in userspace code
u32 is not defined for libbpf when compiled outside of kernel sources (e.g.,
in Github projection). Use __u32 instead.

Fixes: b8c54ea455 ("libbpf: Add support to attach to fentry/fexit tracing progs")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191125212948.1163343-1-andriin@fb.com
2019-11-25 13:52:01 -08:00
Martin KaFai Lau
f9a7cf6eb1 bpf: Introduce BPF_TRACE_x helper for the tracing tests
For BPF_PROG_TYPE_TRACING, the bpf_prog's ctx is an array of u64.
This patch borrows the idea from BPF_CALL_x in filter.h to
convert a u64 to the arg type of the traced function.

The new BPF_TRACE_x has an arg to specify the return type of a bpf_prog.
It will be used in the future TCP-ops bpf_prog that may return "void".

The new macros are defined in the new header file "bpf_trace_helpers.h".
It is under selftests/bpf/ for now.  It could be moved to libbpf later
after seeing more upcoming non-tracing use cases.

The tests are changed to use these new macros also.  Hence,
the k[s]u8/16/32/64 are no longer needed and they are removed
from the bpf_helpers.h.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191123202504.1502696-1-kafai@fb.com
2019-11-24 17:12:11 -08:00
Andrii Nakryiko
1aace10f41 libbpf: Fix bpf_object name determination for bpf_object__open_file()
If bpf_object__open_file() gets path like "some/dir/obj.o", it should derive
BPF object's name as "obj" (unless overriden through opts->object_name).
Instead, due to using `path` as a fallback value for opts->obj_name, path is
used as is for object name, so for above example BPF object's name will be
verbatim "some/dir/obj", which leads to all sorts of troubles, especially when
internal maps are concern (they are using up to 8 characters of object name).
Fix that by ensuring object_name stays NULL, unless overriden.

Fixes: 291ee02b5e ("libbpf: Refactor bpf_object__open APIs to use common opts")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191122003527.551556-1-andriin@fb.com
2019-11-24 16:58:46 -08:00
Andrii Nakryiko
393cdfbee8 libbpf: Support initialized global variables
Initialized global variables are no different in ELF from static variables,
and don't require any extra support from libbpf. But they are matching
semantics of global data (backed by BPF maps) more closely, preventing
LLVM/Clang from aggressively inlining constant values and not requiring
volatile incantations to prevent those. This patch enables global variables.
It still disables uninitialized variables, which will be put into special COM
(common) ELF section, because BPF doesn't allow uninitialized data to be
accessed.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191121070743.1309473-5-andriin@fb.com
2019-11-24 16:58:45 -08:00
Andrii Nakryiko
8983b731ce libbpf: Fix various errors and warning reported by checkpatch.pl
Fix a bunch of warnings and errors reported by checkpatch.pl, to make it
easier to spot new problems.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191121070743.1309473-4-andriin@fb.com
2019-11-24 16:58:45 -08:00
Andrii Nakryiko
1f8e2bcb2c libbpf: Refactor relocation handling
Relocation handling code is convoluted and unnecessarily deeply nested. Split
out per-relocation logic into separate function. Also refactor the logic to be
more a sequence of per-relocation type checks and processing steps, making it
simpler to follow control flow. This makes it easier to further extends it to
new kinds of relocations (e.g., support for extern variables).

This patch also makes relocation's section verification more robust.
Previously relocations against not yet supported externs were silently ignored
because of obj->efile.text_shndx was zero, when all BPF programs had custom
section names and there was no .text section. Also, invalid LDIMM64 relocations
against non-map sections were passed through, if they were pointing to a .text
section (or 0, which is invalid section). All these bugs are fixed within this
refactoring and checks are made more appropriate for each type of relocation.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191121070743.1309473-3-andriin@fb.com
2019-11-24 16:58:45 -08:00
Hewenliang
10992af6bf libtraceevent: Fix memory leakage in copy_filter_type
It is necessary to free the memory that we have allocated when error occurs.

Fixes: ef3072cd1d ("tools lib traceevent: Get rid of die in add_filter_type()")
Signed-off-by: Hewenliang <hewenliang4@huawei.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Link: http://lore.kernel.org/lkml/20191119014415.57210-1-hewenliang4@huawei.com
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-22 10:48:14 -03:00
Sudip Mukherjee
68401a1799 libtraceevent: Fix header installation
When we passed some location in DESTDIR, install_headers called
do_install with DESTDIR as part of the second argument.

But do_install is again using '$(DESTDIR_SQ)$2', so as a result the
headers were installed in a location $DESTDIR/$DESTDIR.

In my testing I passed DESTDIR=/home/sudip/test and the headers were
installed in: /home/sudip/test/home/sudip/test/usr/include/traceevent.

Lets remove DESTDIR from the second argument of do_install so that the
headers are installed in the correct location.

Signed-off-by: Sudipm Mukherjee <sudipm.mukherjee@gmail.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Sudipm Mukherjee <sudipm.mukherjee@gmail.com>
Cc: linux-trace-devel@vger.kernel.org
Link: http://lore.kernel.org/lkml/20191114133719.309-1-sudipm.mukherjee@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-22 10:48:14 -03:00
Andrii Nakryiko
a0d7da26ce libbpf: Fix call relocation offset calculation bug
When relocating subprogram call, libbpf doesn't take into account
relo->text_off, which comes from symbol's value. This generally works fine for
subprograms implemented as static functions, but breaks for global functions.

Taking a simplified test_pkt_access.c as an example:

__attribute__ ((noinline))
static int test_pkt_access_subprog1(volatile struct __sk_buff *skb)
{
        return skb->len * 2;
}

__attribute__ ((noinline))
static int test_pkt_access_subprog2(int val, volatile struct __sk_buff *skb)
{
        return skb->len + val;
}

SEC("classifier/test_pkt_access")
int test_pkt_access(struct __sk_buff *skb)
{
        if (test_pkt_access_subprog1(skb) != skb->len * 2)
                return TC_ACT_SHOT;
        if (test_pkt_access_subprog2(2, skb) != skb->len + 2)
                return TC_ACT_SHOT;
        return TC_ACT_UNSPEC;
}

When compiled, we get two relocations, pointing to '.text' symbol. .text has
st_value set to 0 (it points to the beginning of .text section):

0000000000000008  000000050000000a R_BPF_64_32            0000000000000000 .text
0000000000000040  000000050000000a R_BPF_64_32            0000000000000000 .text

test_pkt_access_subprog1 and test_pkt_access_subprog2 offsets (targets of two
calls) are encoded within call instruction's imm32 part as -1 and 2,
respectively:

0000000000000000 test_pkt_access_subprog1:
       0:       61 10 00 00 00 00 00 00 r0 = *(u32 *)(r1 + 0)
       1:       64 00 00 00 01 00 00 00 w0 <<= 1
       2:       95 00 00 00 00 00 00 00 exit

0000000000000018 test_pkt_access_subprog2:
       3:       61 10 00 00 00 00 00 00 r0 = *(u32 *)(r1 + 0)
       4:       04 00 00 00 02 00 00 00 w0 += 2
       5:       95 00 00 00 00 00 00 00 exit

0000000000000000 test_pkt_access:
       0:       bf 16 00 00 00 00 00 00 r6 = r1
===>   1:       85 10 00 00 ff ff ff ff call -1
       2:       bc 01 00 00 00 00 00 00 w1 = w0
       3:       b4 00 00 00 02 00 00 00 w0 = 2
       4:       61 62 00 00 00 00 00 00 r2 = *(u32 *)(r6 + 0)
       5:       64 02 00 00 01 00 00 00 w2 <<= 1
       6:       5e 21 08 00 00 00 00 00 if w1 != w2 goto +8 <LBB0_3>
       7:       bf 61 00 00 00 00 00 00 r1 = r6
===>   8:       85 10 00 00 02 00 00 00 call 2
       9:       bc 01 00 00 00 00 00 00 w1 = w0
      10:       61 62 00 00 00 00 00 00 r2 = *(u32 *)(r6 + 0)
      11:       04 02 00 00 02 00 00 00 w2 += 2
      12:       b4 00 00 00 ff ff ff ff w0 = -1
      13:       1e 21 01 00 00 00 00 00 if w1 == w2 goto +1 <LBB0_3>
      14:       b4 00 00 00 02 00 00 00 w0 = 2
0000000000000078 LBB0_3:
      15:       95 00 00 00 00 00 00 00 exit

Now, if we compile example with global functions, the setup changes.
Relocations are now against specifically test_pkt_access_subprog1 and
test_pkt_access_subprog2 symbols, with test_pkt_access_subprog2 pointing 24
bytes into its respective section (.text), i.e., 3 instructions in:

0000000000000008  000000070000000a R_BPF_64_32            0000000000000000 test_pkt_access_subprog1
0000000000000048  000000080000000a R_BPF_64_32            0000000000000018 test_pkt_access_subprog2

Calls instructions now encode offsets relative to function symbols and are both
set ot -1:

0000000000000000 test_pkt_access_subprog1:
       0:       61 10 00 00 00 00 00 00 r0 = *(u32 *)(r1 + 0)
       1:       64 00 00 00 01 00 00 00 w0 <<= 1
       2:       95 00 00 00 00 00 00 00 exit

0000000000000018 test_pkt_access_subprog2:
       3:       61 20 00 00 00 00 00 00 r0 = *(u32 *)(r2 + 0)
       4:       0c 10 00 00 00 00 00 00 w0 += w1
       5:       95 00 00 00 00 00 00 00 exit

0000000000000000 test_pkt_access:
       0:       bf 16 00 00 00 00 00 00 r6 = r1
===>   1:       85 10 00 00 ff ff ff ff call -1
       2:       bc 01 00 00 00 00 00 00 w1 = w0
       3:       b4 00 00 00 02 00 00 00 w0 = 2
       4:       61 62 00 00 00 00 00 00 r2 = *(u32 *)(r6 + 0)
       5:       64 02 00 00 01 00 00 00 w2 <<= 1
       6:       5e 21 09 00 00 00 00 00 if w1 != w2 goto +9 <LBB2_3>
       7:       b4 01 00 00 02 00 00 00 w1 = 2
       8:       bf 62 00 00 00 00 00 00 r2 = r6
===>   9:       85 10 00 00 ff ff ff ff call -1
      10:       bc 01 00 00 00 00 00 00 w1 = w0
      11:       61 62 00 00 00 00 00 00 r2 = *(u32 *)(r6 + 0)
      12:       04 02 00 00 02 00 00 00 w2 += 2
      13:       b4 00 00 00 ff ff ff ff w0 = -1
      14:       1e 21 01 00 00 00 00 00 if w1 == w2 goto +1 <LBB2_3>
      15:       b4 00 00 00 02 00 00 00 w0 = 2
0000000000000080 LBB2_3:
      16:       95 00 00 00 00 00 00 00 exit

Thus the right formula to calculate target call offset after relocation should
take into account relocation's target symbol value (offset within section),
call instruction's imm32 offset, and (subtracting, to get relative instruction
offset) instruction index of call instruction itself. All that is shifted by
number of instructions in main program, given all sub-programs are copied over
after main program.

Convert few selftests relying on bpf-to-bpf calls to use global functions
instead of static ones.

Fixes: 48cca7e44f ("libbpf: add support for bpf_call")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191119224447.3781271-1-andriin@fb.com
2019-11-19 15:00:12 -08:00
Luigi Rizzo
3de88c9113 net-af_xdp: Use correct number of channels from ethtool
Drivers use different fields to report the number of channels, so take
the maximum of all data channels (rx, tx, combined) when determining the
size of the xsk map. The current code used only 'combined' which was set
to 0 in some drivers e.g. mlx4.

Tested: compiled and run xdpsock -q 3 -r -S on mlx4

Signed-off-by: Luigi Rizzo <lrizzo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20191119001951.92930-1-lrizzo@google.com
2019-11-19 14:06:35 -08:00
Konstantin Khlebnikov
10f64581b1 libtraceevent: Fix parsing of event %o and %X argument types
Add missing "%o" and "%X". Ext4 events use "%o" for printing i_mode.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
Link: http://lore.kernel.org/lkml/157338066113.6548.11461421296091086041.stgit@buzz
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-18 13:01:59 -03:00
Andrii Nakryiko
7fe74b4362 libbpf: Make global data internal arrays mmap()-able, if possible
Add detection of BPF_F_MMAPABLE flag support for arrays and add it as an extra
flag to internal global data maps, if supported by kernel. This allows users
to memory-map global data and use it without BPF map operations, greatly
simplifying user experience.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-5-andriin@fb.com
2019-11-18 11:41:59 +01:00
Alexei Starovoitov
e7bf94dbb8 libbpf: Add support for attaching BPF programs to other BPF programs
Extend libbpf api to pass attach_prog_fd into bpf_object__open.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-19-ast@kernel.org
2019-11-15 23:45:37 +01:00
Alexei Starovoitov
11d1e2eeff selftests/bpf: Add test for BPF trampoline
Add sanity test for BPF trampoline that checks kernel functions
with up to 6 arguments of different sizes.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-10-ast@kernel.org
2019-11-15 23:43:15 +01:00
Alexei Starovoitov
b8c54ea455 libbpf: Add support to attach to fentry/fexit tracing progs
Teach libbpf to recognize tracing programs types and attach them to
fentry/fexit.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-7-ast@kernel.org
2019-11-15 23:42:31 +01:00
Alexei Starovoitov
1442e2871b libbpf: Introduce btf__find_by_name_kind()
Introduce btf__find_by_name_kind() helper to search BTF by name and kind, since
name alone can be ambiguous.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-6-ast@kernel.org
2019-11-15 23:42:14 +01:00
Magnus Karlsson
a68977d269 libbpf: Allow for creating Rx or Tx only AF_XDP sockets
The libbpf AF_XDP code is extended to allow for the creation of Rx
only or Tx only sockets. Previously it returned an error if the socket
was not initialized for both Rx and Tx.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: William Tu <u9012063@gmail.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/bpf/1573148860-30254-4-git-send-email-magnus.karlsson@intel.com
2019-11-10 19:30:46 -08:00
Magnus Karlsson
cbf07409d0 libbpf: Support XDP_SHARED_UMEM with external XDP program
Add support in libbpf to create multiple sockets that share a single
umem. Note that an external XDP program need to be supplied that
routes the incoming traffic to the desired sockets. So you need to
supply the libbpf_flag XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD and load
your own XDP program.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: William Tu <u9012063@gmail.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/bpf/1573148860-30254-2-git-send-email-magnus.karlsson@intel.com
2019-11-10 19:30:45 -08:00
Toke Høiland-Jørgensen
1a734efe06 libbpf: Add getter for program size
This adds a new getter for the BPF program size (in bytes). This is useful
for a caller that is trying to predict how much memory will be locked by
loading a BPF object into the kernel.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/157333185272.88376.10996937115395724683.stgit@toke.dk
2019-11-10 19:26:30 -08:00
Toke Høiland-Jørgensen
473f4e133a libbpf: Add bpf_get_link_xdp_info() function to get more XDP information
Currently, libbpf only provides a function to get a single ID for the XDP
program attached to the interface. However, it can be useful to get the
full set of program IDs attached, along with the attachment mode, in one
go. Add a new getter function to support this, using an extendible
structure to carry the information. Express the old bpf_get_link_id()
function in terms of the new function.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157333185164.88376.7520653040667637246.stgit@toke.dk
2019-11-10 19:26:30 -08:00
Toke Høiland-Jørgensen
b6e99b010e libbpf: Use pr_warn() when printing netlink errors
The netlink functions were using fprintf(stderr, ) directly to print out
error messages, instead of going through the usual logging macros. This
makes it impossible for the calling application to silence or redirect
those error messages. Fix this by switching to pr_warn() in nlattr.c and
netlink.c.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/157333185055.88376.15999360127117901443.stgit@toke.dk
2019-11-10 19:26:30 -08:00
Toke Høiland-Jørgensen
4f33ddb4e3 libbpf: Propagate EPERM to caller on program load
When loading an eBPF program, libbpf overrides the return code for EPERM
errors instead of returning it to the caller. This makes it hard to figure
out what went wrong on load.

In particular, EPERM is returned when the system rlimit is too low to lock
the memory required for the BPF program. Previously, this was somewhat
obscured because the rlimit error would be hit on map creation (which does
return it correctly). However, since maps can now be reused, object load
can proceed all the way to loading programs without hitting the error;
propagating it even in this case makes it possible for the caller to react
appropriately (and, e.g., attempt to raise the rlimit before retrying).

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/157333184946.88376.11768171652794234561.stgit@toke.dk
2019-11-10 19:26:30 -08:00
Toke Høiland-Jørgensen
ec6d5f47bf libbpf: Unpin auto-pinned maps if loading fails
Since the automatic map-pinning happens during load, it will leave pinned
maps around if the load fails at a later stage. Fix this by unpinning any
pinned maps on cleanup. To avoid unpinning pinned maps that were reused
rather than newly pinned, add a new boolean property on struct bpf_map to
keep track of whether that map was reused or not; and only unpin those maps
that were not reused.

Fixes: 57a00f4164 ("libbpf: Add auto-pinning of maps when loading BPF objects")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/157333184731.88376.9992935027056165873.stgit@toke.dk
2019-11-10 19:26:30 -08:00
Andrii Nakryiko
98e527af30 libbpf: Improve handling of corrupted ELF during map initialization
If we get ELF file with "maps" section, but no symbols pointing to it, we'll
end up with division by zero. Add check against this situation and exit early
with error. Found by Coverity scan against Github libbpf sources.

Fixes: bf82927125 ("libbpf: refactor map initialization")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107020855.3834758-6-andriin@fb.com
2019-11-07 16:20:38 +01:00
Andrii Nakryiko
994021a7e0 libbpf: Make btf__resolve_size logic always check size error condition
Perform size check always in btf__resolve_size. Makes the logic a bit more
robust against corrupted BTF and silences LGTM/Coverity complaining about
always true (size < 0) check.

Fixes: 69eaab04c6 ("btf: extract BTF type size calculation")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107020855.3834758-5-andriin@fb.com
2019-11-07 16:20:38 +01:00
Andrii Nakryiko
dd3ab12637 libbpf: Fix another potential overflow issue in bpf_prog_linfo
Fix few issues found by Coverity and LGTM.

Fixes: b053b439b7 ("bpf: libbpf: bpftool: Print bpf_line_info during prog dump")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107020855.3834758-4-andriin@fb.com
2019-11-07 16:20:38 +01:00
Andrii Nakryiko
4ee1135615 libbpf: Fix potential overflow issue
Fix a potential overflow issue found by LGTM analysis, based on Github libbpf
source code.

Fixes: 3d65014146 ("bpf: libbpf: Add btf_line_info support to libbpf")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107020855.3834758-3-andriin@fb.com
2019-11-07 16:20:37 +01:00
Andrii Nakryiko
3dc5e05982 libbpf: Fix memory leak/double free issue
Coverity scan against Github libbpf code found the issue of not freeing memory and
leaving already freed memory still referenced from bpf_program. Fix it by
re-assigning successfully reallocated memory sooner.

Fixes: 2993e0515b ("tools/bpf: add support to read .BTF.ext sections")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107020855.3834758-2-andriin@fb.com
2019-11-07 16:20:37 +01:00
Andrii Nakryiko
9656b346b2 libbpf: Fix negative FD close() in xsk_setup_xdp_prog()
Fix issue reported by static analysis (Coverity). If bpf_prog_get_fd_by_id()
fails, xsk_lookup_bpf_maps() will fail as well and clean-up code will attempt
close() with fd=-1. Fix by checking bpf_prog_get_fd_by_id() return result and
exiting early.

Fixes: 10a13bb40e ("libbpf: remove qidconf and better support external bpf programs.")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107054059.313884-1-andriin@fb.com
2019-11-07 16:15:27 +01:00
Andrii Nakryiko
ed57802121 libbpf: Simplify BPF_CORE_READ_BITFIELD_PROBED usage
Streamline BPF_CORE_READ_BITFIELD_PROBED interface to follow
BPF_CORE_READ_BITFIELD (direct) and BPF_CORE_READ, in general, i.e., just
return read result or 0, if underlying bpf_probe_read() failed.

In practice, real applications rarely check bpf_probe_read() result, because
it has to always work or otherwise it's a bug. So propagating internal
bpf_probe_read() error from this macro hurts usability without providing real
benefits in practice. This patch fixes the issue and simplifies usage,
noticeable even in selftest itself.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191106201500.2582438-1-andriin@fb.com
2019-11-06 13:54:59 -08:00
James Clark
22bd8f1b5a libsubcmd: Use -O0 with DEBUG=1
When a 'make DEBUG=1' build is done, the command parser is still built
with -O6 and is hard to step through, fix it making it use -O0 in that
case.

Signed-off-by: James Clark <james.clark@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: nd <nd@arm.com>
Link: http://lore.kernel.org/lkml/20191028113340.4282-1-james.clark@arm.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-06 15:49:39 -03:00
James Clark
d894967fca libsubcmd: Move EXTRA_FLAGS to the end to allow overriding existing flags
Move EXTRA_WARNINGS and EXTRA_FLAGS to the end of the compilation line,
otherwise they cannot be used to override the default values.

Signed-off-by: James Clark <james.clark@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: nd <nd@arm.com>
Link: http://lore.kernel.org/lkml/20191028113340.4282-1-james.clark@arm.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-06 15:49:39 -03:00
Andrii Nakryiko
94f060e984 libbpf: Add support for field size relocations
Add bpf_core_field_size() macro, capturing a relocation against field size.
Adjust bits of internal libbpf relocation logic to allow capturing size
relocations of various field types: arrays, structs/unions, enums, etc.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101222810.1246166-4-andriin@fb.com
2019-11-04 16:06:56 +01:00
Andrii Nakryiko
ee26dade0e libbpf: Add support for relocatable bitfields
Add support for the new field relocation kinds, necessary to support
relocatable bitfield reads. Provide macro for abstracting necessary code doing
full relocatable bitfield extraction into u64 value. Two separate macros are
provided:
- BPF_CORE_READ_BITFIELD macro for direct memory read-enabled BPF programs
(e.g., typed raw tracepoints). It uses direct memory dereference to extract
bitfield backing integer value.
- BPF_CORE_READ_BITFIELD_PROBED macro for cases where bpf_probe_read() needs
to be used to extract same backing integer value.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101222810.1246166-3-andriin@fb.com
2019-11-04 16:06:56 +01:00
Toke Høiland-Jørgensen
57a00f4164 libbpf: Add auto-pinning of maps when loading BPF objects
This adds support to libbpf for setting map pinning information as part of
the BTF map declaration, to get automatic map pinning (and reuse) on load.
The pinning type currently only supports a single PIN_BY_NAME mode, where
each map will be pinned by its name in a path that can be overridden, but
defaults to /sys/fs/bpf.

Since auto-pinning only does something if any maps actually have a
'pinning' BTF attribute set, we default the new option to enabled, on the
assumption that seamless pinning is what most callers want.

When a map has a pin_path set at load time, libbpf will compare the map
pinned at that location (if any), and if the attributes match, will re-use
that map instead of creating a new one. If no existing map is found, the
newly created map will instead be pinned at the location.

Programs wanting to customise the pinning can override the pinning paths
using bpf_map__set_pin_path() before calling bpf_object__load() (including
setting it to NULL to disable pinning of a particular map).

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157269298092.394725.3966306029218559681.stgit@toke.dk
2019-11-02 12:35:07 -07:00