The route table that is dumped when the xdp_router_ipv4 process is launched
has the "Gateway" field in non-readable network byte order format, also the
alignment is off when printing the table.
Destination Gateway Genmask Metric Iface
0.0.0.0 196a8c0 0 0 enp7s0
0.0.0.0 196a8c0 0 0 wlp6s0
169.254.0.0 196a8c0 16 0 enp7s0
172.17.0.0 0 16 0 docker0
192.168.150.0 0 24 0 enp7s0
192.168.150.0 0 24 0 wlp6s0
Fix this by converting the "Gateway" field from network byte order Hex into
dotted decimal notation IPv4 format and "Genmask" from CIDR notation into
dotted decimal notation IPv4 format. Also fix the aligntment of the fields
in the route table.
Destination Gateway Genmask Metric Iface
0.0.0.0 192.168.150.1 0.0.0.0 0 enp7s0
0.0.0.0 192.168.150.1 0.0.0.0 0 wlp6s0
169.254.0.0 192.168.150.1 255.255.0.0 0 enp7s0
172.17.0.0 0.0.0.0 255.255.0.0 0 docker0
192.168.150.0 0.0.0.0 255.255.255.0 0 enp7s0
192.168.150.0 0.0.0.0 255.255.255.0 0 wlp6s0
Signed-off-by: Gokul Sivakumar <gokulkumar792@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210919080305.173588-1-gokulkumar792@gmail.com
This adds comments above functions in libbpf.h which document
their uses. These comments are of a format that doxygen and sphinx
can pick up and render. These are rendered by libbpf.readthedocs.org
These doc comments are for:
- bpf_object__find_map_by_name()
- bpf_map__fd()
- bpf_map__is_internal()
- libbpf_get_error()
- libbpf_num_possible_cpus()
Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210918031457.36204-1-grantseltzer@gmail.com
Dave Marchevsky says:
====================
This series introduces a new helper, bpf_trace_vprintk, which functions
like bpf_trace_printk but supports > 3 arguments via a pseudo-vararg u64
array. The bpf_printk libbpf convenience macro is modified to use
bpf_trace_vprintk when > 3 varargs are passed, otherwise the previous
behavior - using bpf_trace_printk - is retained.
Helper functions and macros added during the implementation of
bpf_seq_printf and bpf_snprintf do most of the heavy lifting for
bpf_trace_vprintk. There's no novel format string wrangling here.
Usecase here is straightforward: Giving BPF program writers a more
powerful printk will ease development of BPF programs, particularly
during debugging and testing, where printk tends to be used.
This feature was proposed by Andrii in libbpf mirror's issue tracker
[1].
[1] https://github.com/libbpf/libbpf/issues/315
v5 -> v6: Rebase to pick up newly-added helper
v4 -> v5:
* patch 8: added test for "%pS" format string w/ NULL fmt arg [Daniel]
* patch 8: dmesg -> /sys/kernel/debug/tracing/trace_pipe in commit message [Andrii]
* patch 9: squash into patch 8, remove the added test in favor of just bpf_printk'ing in patch 8's test [Andrii]
* migrate comment to /* */
* header comments improved$
* uapi/linux/bpf.h: u64 -> long return type [Daniel]
* uapi/linux/bpf.h: function description explains benefit of bpf_trace_vprintk over bpf_trace_printk [Daniel]
* uapi/linux/bpf.h: added patch explaining that data_len should be a multiple of 8 in bpf_seq_printf, bpf_snprintf descriptions [Daniel]
* tools/lib/bpf/bpf_helpers.h: move comment to new bpf_printk [Andrii]
* rebase
v3 -> v4:
* Add patch 2, which migrates reference_tracking prog_test away from
bpf_program__load. Could be placed a bit later in the series, but
wanted to keep the actual vprintk-related patches contiguous
* Add patch 9, which adds a program w/ 0 fmt arg bpf_printk to vprintk
test
* bpf_printk convenience macro isn't multiline anymore, so simplify [Andrii]
* Add some comments to ___bpf_pick_printk to make it more obvious when
implementation switches from printk to vprintk [Andrii]
* BPF_PRINTK_FMT_TYPE -> BPF_PRINTK_FMT_MOD for 'static const' fmt string
in printk wrapper macro [Andrii]
* checkpatch.pl doesn't like this, says "Macros with complex values
should be enclosed in parentheses". Strange that it didn't have similar
complaints about v3's BPF_PRINTK_FMT_TYPE. Regardless, IMO the complaint
is not highlighting a real issue in the case of this macro.
* Fix alignment of __bpf_vprintk and __bpf_pick_printk [Andrii]
* rebase
v2 -> v3:
* Clean up patch 3's commit message [Alexei]
* Add patch 4, which modifies __bpf_printk to use 'static const char' to
store fmt string with fallback for older kernels [Andrii]
* rebase
v1 -> v2:
* Naming conversation seems to have gone in favor of keeping
bpf_trace_vprintk, names are unchanged
* Patch 3 now modifies bpf_printk convenience macro to choose between
__bpf_printk and __bpf_vprintk 'implementation' macros based on arg
count. __bpf_vprintk is a renaming of bpf_vprintk convenience macro
from v1, __bpf_printk is the existing bpf_printk implementation.
This patch could use some scrutiny as I think current implementation
may regress developer experience in a specific case, turning a
compile-time error into a load-time error. Unclear to me how
common the case is, or whether the macro magic I chose is ideal.
* char ___fmt[] to static const char ___fmt[] change was not done,
wanted to leave __bpf_printk 'implementation' macro unchanged for v2
to ease discussion of above point
* Removed __always_inline from __set_printk_clr_event [Andrii]
* Simplified bpf_trace_printk docstring to refer to other functions
instead of copy/pasting and avoid specifying 12 vararg limit [Andrii]
* Migrated trace_printk selftest to use ASSERT_ instead of CHECK
* Adds new patch 5, previous patch 5 is now 6
* Migrated trace_vprintk selftest to use ASSERT_ instead of CHECK,
open_and_load instead of separate open, load [Andrii]
* Patch 2's commit message now correctly mentions trace_pipe instead of
dmesg [Andrii]
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit adds a test prog for vprintk which confirms that:
* bpf_trace_vprintk is writing to /sys/kernel/debug/tracing/trace_pipe
* __bpf_vprintk macro works as expected
* >3 args are printed
* bpf_printk w/ 0 format args compiles
* bpf_trace_vprintk call w/ a fmt specifier but NULL fmt data fails
Approach and code are borrowed from trace_printk test.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210917182911.2426606-9-davemarchevsky@fb.com
The __bpf_printk convenience macro was using a 'char' fmt string holder
as it predates support for globals in libbpf. Move to more efficient
'static const char', but provide a fallback to the old way via
BPF_NO_GLOBAL_DATA so users on old kernels can still use the macro.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210917182911.2426606-6-davemarchevsky@fb.com
Instead of being a thin wrapper which calls into bpf_trace_printk,
libbpf's bpf_printk convenience macro now chooses between
bpf_trace_printk and bpf_trace_vprintk. If the arg count (excluding
format string) is >3, use bpf_trace_vprintk, otherwise use the older
helper.
The motivation behind this added complexity - instead of migrating
entirely to bpf_trace_vprintk - is to maintain good developer experience
for users compiling against new libbpf but running on older kernels.
Users who are passing <=3 args to bpf_printk will see no change in their
bytecode.
__bpf_vprintk functions similarly to BPF_SEQ_PRINTF and BPF_SNPRINTF
macros elsewhere in the file - it allows use of bpf_trace_vprintk
without manual conversion of varargs to u64 array. Previous
implementation of bpf_printk macro is moved to __bpf_printk for use by
the new implementation.
This does change behavior of bpf_printk calls with >3 args in the "new
libbpf, old kernels" scenario. Before this patch, attempting to use 4
args to bpf_printk results in a compile-time error. After this patch,
using bpf_printk with 4 args results in a trace_vprintk helper call
being emitted and a load-time failure on older kernels.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210917182911.2426606-5-davemarchevsky@fb.com
bpf_program__load is not supposed to be used directly. Replace it with
bpf_object__ APIs for the reference_tracking prog_test, which is the
last offender in bpf selftests.
Some additional complexity is added for this test, namely the use of one
bpf_object to iterate through progs, while a second bpf_object is
created and opened/closed to test actual loading of progs. This is
because the test was doing bpf_program__load then __unload to test
loading of individual progs and same semantics with
bpf_object__load/__unload result in failure to load an __unload-ed obj.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210917182911.2426606-3-davemarchevsky@fb.com
MAX_SNPRINTF_VARARGS and MAX_SEQ_PRINTF_VARARGS are used by bpf helpers
bpf_snprintf and bpf_seq_printf to limit their varargs. Both call into
bpf_bprintf_prepare for print formatting logic and have convenience
macros in libbpf (BPF_SNPRINTF, BPF_SEQ_PRINTF) which use the same
helper macros to convert varargs to a byte array.
Changing shared functionality to support more varargs for either bpf
helper would affect the other as well, so let's combine the _VARARGS
macros to make this more obvious.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210917182911.2426606-2-davemarchevsky@fb.com
Alexei Starovoitov says:
====================
pull-request: bpf-next 2021-09-17
We've added 63 non-merge commits during the last 12 day(s) which contain
a total of 65 files changed, 2653 insertions(+), 751 deletions(-).
The main changes are:
1) Streamline internal BPF program sections handling and
bpf_program__set_attach_target() in libbpf, from Andrii.
2) Add support for new btf kind BTF_KIND_TAG, from Yonghong.
3) Introduce bpf_get_branch_snapshot() to capture LBR, from Song.
4) IMUL optimization for x86-64 JIT, from Jie.
5) xsk selftest improvements, from Magnus.
6) Introduce legacy kprobe events support in libbpf, from Rafael.
7) Access hw timestamp through BPF's __sk_buff, from Vadim.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (63 commits)
selftests/bpf: Fix a few compiler warnings
libbpf: Constify all high-level program attach APIs
libbpf: Schedule open_opts.attach_prog_fd deprecation since v0.7
selftests/bpf: Switch fexit_bpf2bpf selftest to set_attach_target() API
libbpf: Allow skipping attach_func_name in bpf_program__set_attach_target()
libbpf: Deprecated bpf_object_open_opts.relaxed_core_relocs
selftests/bpf: Stop using relaxed_core_relocs which has no effect
libbpf: Use pre-setup sec_def in libbpf_find_attach_btf_id()
bpf: Update bpf_get_smp_processor_id() documentation
libbpf: Add sphinx code documentation comments
selftests/bpf: Skip btf_tag test if btf_tag attribute not supported
docs/bpf: Add documentation for BTF_KIND_TAG
selftests/bpf: Add a test with a bpf program with btf_tag attributes
selftests/bpf: Test BTF_KIND_TAG for deduplication
selftests/bpf: Add BTF_KIND_TAG unit tests
selftests/bpf: Change NAME_NTH/IS_NAME_NTH for BTF_KIND_TAG format
selftests/bpf: Test libbpf API function btf__add_tag()
bpftool: Add support for BTF_KIND_TAG
libbpf: Add support for BTF_KIND_TAG
libbpf: Rename btf_{hash,equal}_int to btf_{hash,equal}_int_tag
...
====================
Link: https://lore.kernel.org/r/20210917173738.3397064-1-ast@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Clang warns twice:
drivers/ptp/ptp_ocp.c:2065:16: error: operator '?:' has lower precedence
than '&'; '&' will be evaluated first
[-Werror,-Wbitwise-conditional-parentheses]
on & map ? " ON" : "OFF", src);
~~~~~~~~ ^
drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '&'
expression to silence this warning
on & map ? " ON" : "OFF", src);
^
( )
drivers/ptp/ptp_ocp.c:2065:16: note: place parentheses around the '?:'
expression to evaluate it first
on & map ? " ON" : "OFF", src);
^
on and map are both booleans so this should be a logical AND, which
clears up the operator precedence issue.
Fixes: a62a56d04e ("ptp: ocp: Enable 4th timestamper / PPS generator")
Link: https://github.com/ClangBuiltLinux/linux/issues/1457
Suggested-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/r/20210917045204.1385801-1-nathan@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
With clang building selftests/bpf, I hit a few warnings like below:
.../bpf_iter.c:592:48: warning: variable 'expected_key_c' set but not used [-Wunused-but-set-variable]
__u32 expected_key_a = 0, expected_key_b = 0, expected_key_c = 0;
^
.../bpf_iter.c:688:48: warning: variable 'expected_key_c' set but not used [-Wunused-but-set-variable]
__u32 expected_key_a = 0, expected_key_b = 0, expected_key_c = 0;
^
.../tc_redirect.c:657:6: warning: variable 'target_fd' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
if (!ASSERT_OK_PTR(nstoken, "setns " NS_FWD))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.../tc_redirect.c:743:6: note: uninitialized use occurs here
if (target_fd >= 0)
^~~~~~~~~
Removing unused variables and initializing the previously-uninitialized variable
to ensure these warnings are gone.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210917043343.3711917-1-yhs@fb.com
Andrii Nakryiko says:
====================
This patch set deprecates bpf_object_open_opts.attach_prog_fd (in libbpf 0.7+)
by extending bpf_program__set_attach_target() to support some more flexible
scenarios. Existing fexit_bpf2bpf selftest is updated accordingly to not use
deprecated APIs.
While at it, also deprecate no-op relaxed_core_relocs option (they are always
"relaxed").
Last patch also const-ifies all high-level libbpf attach APIs, as there is no
reason for them to assume bpf_program/bpf_map modifications.
Patch #1 also removes one more unneeded use of find_sec_def(), relying on
prog->sec_def that's set during bpf_object__open() operation, simplifying
upcoming refactoring a little bit more.
All these changes are preparatory patches before SEC() handling refactoring
that will come next.
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
bpf_object_open_opts.attach_prog_fd makes a pretty strong assumption
that bpf_object contains either only single freplace BPF program or all
of BPF programs in BPF object are freplaces intended to replace
different subprograms of the same target BPF program. This seems both
a bit confusing, too assuming, and limiting.
We've had bpf_program__set_attach_target() API which allows more
fine-grained control over this, on a per-program level. As such, mark
open_opts.attach_prog_fd as deprecated starting from v0.7, so that we
have one more universal way of setting freplace targets. With previous
change to allow NULL attach_func_name argument, and especially combined
with BPF skeleton, arguable bpf_program__set_attach_target() is a more
convenient and explicit API as well.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210916015836.1248906-7-andrii@kernel.org
Switch fexit_bpf2bpf selftest to bpf_program__set_attach_target()
instead of using bpf_object_open_opts.attach_prog_fd, which is going to
be deprecated. These changes also demonstrate the new mode of
set_attach_target() in which it allows NULL when the target is BPF
program (attach_prog_fd != 0).
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210916015836.1248906-6-andrii@kernel.org
Allow to use bpf_program__set_attach_target to only set target attach
program FD, while letting libbpf to use target attach function name from
SEC() definition. This might be useful for some scenarios where
bpf_object contains multiple related freplace BPF programs intended to
replace different sub-programs in target BPF program. In such case all
programs will have the same attach_prog_fd, but different
attach_func_name. It's convenient to specify such target function names
declaratively in SEC() definitions, but attach_prog_fd is a dynamic
runtime setting.
To simplify such scenario, allow bpf_program__set_attach_target() to
delay BTF ID resolution till the BPF program load time by providing NULL
attach_func_name. In that case the behavior will be similar to using
bpf_object_open_opts.attach_prog_fd (which is marked deprecated since
v0.7), but has the benefit of allowing more control by user in what is
attached to what. Such setup allows having BPF programs attached to
different target attach_prog_fd with target functions still declaratively
recorded in BPF source code in SEC() definitions.
Selftests changes in the next patch should make this more obvious.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210916015836.1248906-5-andrii@kernel.org
The MODULE_DEVICE_TABLE already creates proper alias for spi driver.
Having another MODULE_ALIAS causes the alias to be duplicated.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Gokul Sivakumar
Grant Seltzer
Alexei Starovoitov
Dave Marchevsky
Jakub Kicinski
Florian Fainelli
Nathan Chancellor
Yonghong Song
Andrii Nakryiko
Krzysztof Kozlowski