Remove the need to explicitly pass bpf_sec_def for auto-attachable BPF
programs, as it is already recorded at bpf_object__open() time for all
recognized type of BPF programs. This further reduces number of explicit
calls to find_sec_def(), simplifying further refactorings.
No functional changes are done by this patch.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210914014733.2768-4-andrii@kernel.org
Refactor bpf_object__open() sequencing to perform BPF program type
detection based on SEC() definitions before we get to relocations
collection. This allows to have more information about BPF program by
the time we get to, say, struct_ops relocation gathering. This,
subsequently, simplifies struct_ops logic and removes the need to
perform extra find_sec_def() resolution.
With this patch libbpf will require all struct_ops BPF programs to be
marked with SEC("struct_ops") or SEC("struct_ops/xxx") annotations.
Real-world applications are already doing that through something like
selftests's BPF_STRUCT_OPS() macro. This change streamlines libbpf's
internal handling of SEC() definitions and is in the sprit of
upcoming libbpf-1.0 section strictness changes ([0]).
[0] https://github.com/libbpf/libbpf/wiki/Libbpf:-the-road-to-v1.0#stricter-and-more-uniform-bpf-program-section-name-sec-handling
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210914014733.2768-3-andrii@kernel.org
Allow kprobe tracepoint events creation through legacy interface, as the
kprobe dynamic PMUs support, used by default, was only created in v4.17.
Store legacy kprobe name in struct bpf_perf_link, instead of creating
a new "subclass" off of bpf_perf_link. This is ok as it's just two new
fields, which are also going to be reused for legacy uprobe support in
follow up patches.
Signed-off-by: Rafael David Tinoco <rafaeldtinoco@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210912064844.3181742-1-rafaeldtinoco@gmail.com
Turn previously auto-generated libbpf_version.h header into a normal
header file. This prevents various tricky Makefile integration issues,
simplifies the overall build process, but also allows to further extend
it with some more versioning-related APIs in the future.
To prevent accidental out-of-sync versions as defined by libbpf.map and
libbpf_version.h, Makefile checks their consistency at build time.
Simultaneously with this change bump libbpf.map to v0.6.
Also undo adding libbpf's output directory into include path for
kernel/bpf/preload, bpftool, and resolve_btfids, which is not necessary
because libbpf_version.h is just a normal header like any other.
Fixes: 0b46b75505 ("libbpf: Add LIBBPF_DEPRECATED_SINCE macro for scheduling API deprecations")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210913222309.3220849-1-andrii@kernel.org
The tailcall_3 test program uses bpf_tail_call_static() where the JIT
would patch a direct jump. Add a new tailcall_6 test program replicating
exactly the same test just ensuring that bpf_tail_call() uses a map
index where the verifier cannot make assumptions this time.
In other words, this will now cover both on x86-64 JIT, meaning, JIT
images with emit_bpf_tail_call_direct() emission as well as JIT images
with emit_bpf_tail_call_indirect() emission.
# echo 1 > /proc/sys/net/core/bpf_jit_enable
# ./test_progs -t tailcalls
#136/1 tailcalls/tailcall_1:OK
#136/2 tailcalls/tailcall_2:OK
#136/3 tailcalls/tailcall_3:OK
#136/4 tailcalls/tailcall_4:OK
#136/5 tailcalls/tailcall_5:OK
#136/6 tailcalls/tailcall_6:OK
#136/7 tailcalls/tailcall_bpf2bpf_1:OK
#136/8 tailcalls/tailcall_bpf2bpf_2:OK
#136/9 tailcalls/tailcall_bpf2bpf_3:OK
#136/10 tailcalls/tailcall_bpf2bpf_4:OK
#136/11 tailcalls/tailcall_bpf2bpf_5:OK
#136 tailcalls:OK
Summary: 1/11 PASSED, 0 SKIPPED, 0 FAILED
# echo 0 > /proc/sys/net/core/bpf_jit_enable
# ./test_progs -t tailcalls
#136/1 tailcalls/tailcall_1:OK
#136/2 tailcalls/tailcall_2:OK
#136/3 tailcalls/tailcall_3:OK
#136/4 tailcalls/tailcall_4:OK
#136/5 tailcalls/tailcall_5:OK
#136/6 tailcalls/tailcall_6:OK
[...]
For interpreter, the tailcall_1-6 tests are passing as well. The later
tailcall_bpf2bpf_* are failing due lack of bpf2bpf + tailcall support
in interpreter, so this is expected.
Also, manual inspection shows that both loaded programs from tailcall_3
and tailcall_6 test case emit the expected opcodes:
* tailcall_3 disasm, emit_bpf_tail_call_direct():
[...]
b: push %rax
c: push %rbx
d: push %r13
f: mov %rdi,%rbx
12: movabs $0xffff8d3f5afb0200,%r13
1c: mov %rbx,%rdi
1f: mov %r13,%rsi
22: xor %edx,%edx _
24: mov -0x4(%rbp),%eax | limit check
2a: cmp $0x20,%eax |
2d: ja 0x0000000000000046 |
2f: add $0x1,%eax |
32: mov %eax,-0x4(%rbp) |_
38: nopl 0x0(%rax,%rax,1)
3d: pop %r13
3f: pop %rbx
40: pop %rax
41: jmpq 0xffffffffffffe377
[...]
* tailcall_6 disasm, emit_bpf_tail_call_indirect():
[...]
47: movabs $0xffff8d3f59143a00,%rsi
51: mov %edx,%edx
53: cmp %edx,0x24(%rsi)
56: jbe 0x0000000000000093 _
58: mov -0x4(%rbp),%eax | limit check
5e: cmp $0x20,%eax |
61: ja 0x0000000000000093 |
63: add $0x1,%eax |
66: mov %eax,-0x4(%rbp) |_
6c: mov 0x110(%rsi,%rdx,8),%rcx
74: test %rcx,%rcx
77: je 0x0000000000000093
79: pop %rax
7a: mov 0x30(%rcx),%rcx
7e: add $0xb,%rcx
82: callq 0x000000000000008e
87: pause
89: lfence
8c: jmp 0x0000000000000087
8e: mov %rcx,(%rsp)
92: retq
[...]
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Acked-by: Paul Chaignon <paul@cilium.io>
Link: https://lore.kernel.org/bpf/CAM1=_QRyRVCODcXo_Y6qOm1iT163HoiSj8U2pZ8Rj3hzMTT=HQ@mail.gmail.com
Link: https://lore.kernel.org/bpf/20210910091900.16119-1-daniel@iogearbox.net
Introduce bpf_get_branch_snapshot(), which allows tracing pogram to get
branch trace from hardware (e.g. Intel LBR). To use the feature, the
user need to create perf_event with proper branch_record filtering
on each cpu, and then calls bpf_get_branch_snapshot in the bpf function.
On Intel CPUs, VLBR event (raw event 0x1b00) can be use for this.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210910183352.3151445-3-songliubraving@fb.com
BPF programs may want to know hardware timestamps if NIC supports
such timestamping.
Expose this data as hwtstamp field of __sk_buff the same way as
gso_segs/gso_size. This field could be accessed from the same
programs as tstamp field, but it's read-only field. Explicit test
to deny access to padding data is added to bpf_skb_is_valid_access.
Also update BPF_PROG_TEST_RUN tests of the feature.
Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210909220409.8804-2-vfedorenko@novek.ru
Add tests for invalid xsk descriptors in the Tx ring. A number of
handcrafted nasty invalid descriptors are created and submitted to the
tx ring to check that they are validated correctly. Corner case valid
ones are also sent. The tests are run for both aligned and unaligned
mode.
pkt_stream_set() is introduced to be able to create a hand-crafted
packet stream where every single packet is specified in detail.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-20-magnus.karlsson@gmail.com
Eliminate a test specific if-statement for the RX_FILL_EMTPY stats
test that is present in the test runner. We can do this as we now have
the use_addr_for_fill option. Just create and empty Rx packet stream
and indicated that the test runner should use the addresses in that to
populate the fill ring. As there are no packets in the stream, the
fill ring will be empty and we will get the error stats that we want
to test.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-19-magnus.karlsson@gmail.com
Add a test for unaligned mode in which packet buffers can be placed
anywhere within the umem. Some packets are made to straddle page
boundaries in order to check for correctness. On the Tx side, buffers
are now allocated according to the addresses found in the packet
stream. Thus, the placement of buffers can be controlled with the
boolean use_addr_for_fill in the packet stream.
One new pkt_stream interface is introduced: pkt_stream_replace_half()
that replaces every other packet in the default packet stream with the
specified new packet. The constant DEFAULT_OFFSET is also
introduced. It specifies at what offset from the start of a chunk a Tx
packet is placed by the sending thread. This is just to be able to
test that it is possible to send packets at an offset not equal to
zero.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-18-magnus.karlsson@gmail.com
Introduce the concept of a default packet stream that is the set of
packets sent by most tests. Then add the ability to replace it for a
test that would like to send or receive something else through the use
of the function pkt_stream_replace() and then restored with
pkt_stream_restore_default(). These are then used to convert the
STAT_TEST_TX_INVALID to use these new APIs.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-17-magnus.karlsson@gmail.com
Make xdp_flags and bind_flags local instead of global by moving them
into the interface object. These flags decide if the socket should be
created in SKB mode or in DRV mode and therefore they are sticky and
will survive a test_spec_reset. Since every test is first run in SKB
mode then in DRV mode, this change only happens once. With this
change, the configured_mode global variable can also be
erradicated. The first test_spec_init() also becomes superfluous and
can be eliminated.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-13-magnus.karlsson@gmail.com
Replace the second_step global variable with a test specification
variable called total_steps that a test can be set to indicate how
many times the packet stream should be sent without reinitializing any
sockets. This eliminates test specific code in the test runner around
the bidirectional test.
The total_steps variable is 1 by default as most tests only need a
single round of packets.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-11-magnus.karlsson@gmail.com
Introduce a test specification to be able to concisely describe a
test. Currently, a test is implemented by sprinkling test specific if
statements here and there, which is not scalable or easy to
understand. The end goal with this patch set is to come to the point
in which a test is completely specified by a test specification that
can easily be constructed in a single function so that new tests can
be added without too much trouble. This test specification will be run
by a test runner that has no idea about tests. It just executes the
what test specification states.
This patch introduces the test specification and, as a start, puts the
two interface objects in there, one containing the packet stream to be
sent and the other one the packet stream that is supposed to be
received for a test to pass. The global variables containing these can
then be eliminated. The following patches will convert each existing
test into a test specification and add the needed fields into it and
the functionality in the test runner that act on the test
specification. At the end, the test runner should contain no test
specific code and each test should be described in a single simple
function.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-4-magnus.karlsson@gmail.com
Simplify the xsk_info and umem_info allocation by allocating them
upfront in an array, instead of allocating an array of pointers to
future creations of these. Allocating them upfront also has the
advantage that configuration information can be stored in these
structures instead of relying on global variables. With the previous
structure, xsk_info and umem_info were created too late to be able to
store most configuration information. This will be used to eliminate
most global variables in later patches in this series.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-2-magnus.karlsson@gmail.com
Introduce a macro LIBBPF_DEPRECATED_SINCE(major, minor, message) to prepare
the deprecation of two API functions. This macro marks functions as deprecated
when libbpf's version reaches the values passed as an argument.
As part of this change libbpf_version.h header is added with recorded major
(LIBBPF_MAJOR_VERSION) and minor (LIBBPF_MINOR_VERSION) libbpf version macros.
They are now part of libbpf public API and can be relied upon by user code.
libbpf_version.h is installed system-wide along other libbpf public headers.
Due to this new build-time auto-generated header, in-kernel applications
relying on libbpf (resolve_btfids, bpftool, bpf_preload) are updated to
include libbpf's output directory as part of a list of include search paths.
Better fix would be to use libbpf's make_install target to install public API
headers, but that clean up is left out as a future improvement. The build
changes were tested by building kernel (with KBUILD_OUTPUT and O= specified
explicitly), bpftool, libbpf, selftests/bpf, and resolve_btfids builds. No
problems were detected.
Note that because of the constraints of the C preprocessor we have to write
a few lines of macro magic for each version used to prepare deprecation (0.6
for now).
Also, use LIBBPF_DEPRECATED_SINCE() to schedule deprecation of
btf__get_from_id() and btf__load(), which are replaced by
btf__load_from_kernel_by_id() and btf__load_into_kernel(), respectively,
starting from future libbpf v0.6. This is part of libbpf 1.0 effort ([0]).
[0] Closes: https://github.com/libbpf/libbpf/issues/278
Co-developed-by: Quentin Monnet <quentin@isovalent.com>
Co-developed-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210908213226.1871016-1-andrii@kernel.org
This adds a skeleton method X__elf_bytes() which returns the binary data of
the compiled and embedded BPF object file. It additionally sets the size of
the return data to the provided size_t pointer argument.
The assignment to s->data is cast to void * to ensure no warning is issued if
compiled with a previous version of libbpf where the bpf_object_skeleton field
is void * instead of const void *
Signed-off-by: Matt Smith <alastorze@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210901194439.3853238-3-alastorze@fb.com
This change was necessary to enforce the implied contract
that bpf_object_skeleton->data should not be mutated. The data
will be cast to `void *` during assignment to handle the case
where a user is compiling with older libbpf headers to avoid
a compiler warning of `const void *` data being cast to `void *`
Signed-off-by: Matt Smith <alastorze@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210901194439.3853238-2-alastorze@fb.com
If libbpf encounters an ELF file that has been stripped of its symbol
table, it will crash in bpf_object__add_programs() when trying to
dereference the obj->efile.symbols pointer.
Fix this by erroring out of bpf_object__elf_collect() if it is not able
able to find the symbol table.
v2:
- Move check into bpf_object__elf_collect() and add nice error message
Fixes: 6245947c1b ("libbpf: Allow gaps in BPF program sections to support overriden weak functions")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210901114812.204720-1-toke@redhat.com
bpf_prog_test_run_xattr takes a struct __sk_buff, but did not permit
that __skbuff to include an nonzero ingress_ifindex.
This patch updates to allow ingress_ifindex, convert the __sk_buff field to
sk_buff (skb_iif) and back, and tests that the value is present from on BPF
program side. The test sets an unlikely distinct value for ingress_ifindex
(11) from ifindex (1), which is in line with the rest of the synthetic field
tests.
Adding this support allows testing BPF that operates differently on
incoming and outgoing skbs by discriminating on this field.
Signed-off-by: Neil Spring <ntspring@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210831033356.1459316-1-ntspring@fb.com
Pull perf tool updates from Arnaldo Carvalho de Melo:
"New features:
- Improvements for the flamegraph python script, including:
- Display perf.data header
- Display PIDs of user stacks
- Added option to change color scheme
- Default to blue/green color scheme to improve accessibility
- Correctly identify kernel stacks when debuginfo is available
- Improvements for 'perf bench futex':
- Add --mlockall parameter
- Add --broadcast and --pi to the 'requeue' sub benchmark
- Add support for PMU aliases.
- Introduce an ARM Coresight ETE decoder.
- Add a 'perf bench' entry for evlist open/close operations, to help
quantify improvements with multithreading 'perf record'.
- Allow reporting the [un]throttle PERF_RECORD_ meta event in 'perf
script's python scripting.
- Add a 'perf test' entry for PMU aliases.
- Add a 'perf test' entry for 'perf record/perf report/perf script'
pipe mode.
Fixes:
- perf script dlfilter (API for filtering via dynamically loaded
shared object introduced in v5.14) fixes and a 'perf test' entry
for it.
- Fix get_current_dir_name() compilation on Android.
- Fix issues with asciidoc and double dashes uses.
- Fix memory leaks in the BTF handling code.
- Fix leftover problems in the Documentation from the infrastructure
originally lifted from the git codebase.
- Fix *probe_vfs_getname.sh 'perf test' failures.
- Handle fd gaps in 'perf test's test__dso_data_reopen().
- Make sure to show disasembly warnings for 'perf annotate --stdio'.
- Fix output from pipe to file and vice-versa in 'perf
record/report/script'.
- Correct 'perf data -h' output.
- Fix wrong comm in system-wide mode with 'perf record --delay'.
- Do not allow --for-each-cgroup without cpu in 'perf stat'
- Make 'perf test --skip' work on shell tests.
- Fix libperf's verbose printing.
Misc improvements:
- Preparatory patches for multithreading various 'perf record' phases
(synthesizing, opening, recording, etc).
- Add sparse context/locking annotations in compiler-types.h, also to
help with the multithreading effort.
- Optimize the generation of the arch specific erno tables used in
'perf trace'.
- Optimize libperf's perf_cpu_map__max().
- Improve ARM's CoreSight warnings.
- Report collisions in AUX records.
- Improve warnings for the LLVM 'perf test' entry.
- Improve the PMU events 'perf test' codebase.
- perf test: Do not compare overheads in the zstd comp test
- Better support annotation on ARM.
- Update 'perf trace's cmd string table to decode sys_bpf() first
arg.
Vendor events:
- Add JSON events and metrics for Intel's Ice Lake, Tiger Lake and
Elhart Lake.
- Update JSON eventsand metrics for Intel's Cascade Lake and Sky Lake
servers.
Hardware tracing:
- Improvements for the ARM hardware tracing auxtrace support"
* tag 'perf-tools-for-v5.15-2021-09-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (130 commits)
perf tests: Add test for PMU aliases
perf pmu: Add PMU alias support
perf session: Report collisions in AUX records
perf script python: Allow reporting the [un]throttle PERF_RECORD_ meta event
perf build: Report failure for testing feature libopencsd
perf cs-etm: Show a warning for an unknown magic number
perf cs-etm: Print the decoder name
perf cs-etm: Create ETE decoder
perf cs-etm: Update OpenCSD decoder for ETE
perf cs-etm: Fix typo
perf cs-etm: Save TRCDEVARCH register
perf cs-etm: Refactor out ETMv4 header saving
perf cs-etm: Initialise architecture based on TRCIDR1
perf cs-etm: Refactor initialisation of decoder params.
tools build: Fix feature detect clean for out of source builds
perf evlist: Add evlist__for_each_entry_from() macro
perf evsel: Handle precise_ip fallback in evsel__open_cpu()
perf evsel: Move bpf_counter__install_pe() to success path in evsel__open_cpu()
perf evsel: Move test_attr__open() to success path in evsel__open_cpu()
perf evsel: Move ignore_missing_thread() to fallback code
...
Pull tracing updates from Steven Rostedt:
- simplify the Kconfig use of FTRACE and TRACE_IRQFLAGS_SUPPORT
- bootconfig can now start histograms
- bootconfig supports group/all enabling
- histograms now can put values in linear size buckets
- execnames can be passed to synthetic events
- introduce "event probes" that attach to other events and can retrieve
data from pointers of fields, or record fields as different types (a
pointer to a string as a string instead of just a hex number)
- various fixes and clean ups
* tag 'trace-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (35 commits)
tracing/doc: Fix table format in histogram code
selftests/ftrace: Add selftest for testing duplicate eprobes and kprobes
selftests/ftrace: Add selftest for testing eprobe events on synthetic events
selftests/ftrace: Add test case to test adding and removing of event probe
selftests/ftrace: Fix requirement check of README file
selftests/ftrace: Add clear_dynamic_events() to test cases
tracing: Add a probe that attaches to trace events
tracing/probes: Reject events which have the same name of existing one
tracing/probes: Have process_fetch_insn() take a void * instead of pt_regs
tracing/probe: Change traceprobe_set_print_fmt() to take a type
tracing/probes: Use struct_size() instead of defining custom macros
tracing/probes: Allow for dot delimiter as well as slash for system names
tracing/probe: Have traceprobe_parse_probe_arg() take a const arg
tracing: Have dynamic events have a ref counter
tracing: Add DYNAMIC flag for dynamic events
tracing: Replace deprecated CPU-hotplug functions.
MAINTAINERS: Add an entry for os noise/latency
tracepoint: Fix kerneldoc comments
bootconfig/tracing/ktest: Update ktest example for boot-time tracing
tools/bootconfig: Use per-group/all enable option in ftrace2bconf script
...
Pull Kselftest updates from Shuah Khan:
"Fixes to build and test failures:
- openat2 test failure for O_LARGEFILE flag on ARM64
- x86 test build failures related to glibc 2.34 adding support for
variable sized MINSIGSTKSZ and SIGSTKSZ
- removing obsolete configs in sync and cpufreq config files
- minor spelling and duplicate header include cleanups"
* tag 'linux-kselftest-next-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
selftests/cpufreq: Rename DEBUG_PI_LIST to DEBUG_PLIST
selftests/sync: Remove the deprecated config SYNC
selftests: safesetid: Fix spelling mistake "cant" -> "can't"
selftests/x86: Fix error: variably modified 'altstack_data' at file scope
kselftest:sched: remove duplicate include in cs_prctl_test.c
selftests: openat2: Fix testing failure for O_LARGEFILE flag
Pull powerpc updates from Michael Ellerman:
- Convert pseries & powernv to use MSI IRQ domains.
- Rework the pseries CPU numbering so that CPUs that are removed, and
later re-added, are given a CPU number on the same node as
previously, when possible.
- Add support for a new more flexible device-tree format for specifying
NUMA distances.
- Convert powerpc to GENERIC_PTDUMP.
- Retire sbc8548 and sbc8641d board support.
- Various other small features and fixes.
Thanks to Alexey Kardashevskiy, Aneesh Kumar K.V, Anton Blanchard,
Cédric Le Goater, Christophe Leroy, Emmanuel Gil Peyrot, Fabiano Rosas,
Fangrui Song, Finn Thain, Gautham R. Shenoy, Hari Bathini, Joel
Stanley, Jordan Niethe, Kajol Jain, Laurent Dufour, Leonardo Bras, Lukas
Bulwahn, Marc Zyngier, Masahiro Yamada, Michal Suchanek, Nathan
Chancellor, Nicholas Piggin, Parth Shah, Paul Gortmaker, Pratik R.
Sampat, Randy Dunlap, Sebastian Andrzej Siewior, Srikar Dronamraju, Wan
Jiabing, Xiongwei Song, and Zheng Yongjun.
* tag 'powerpc-5.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (154 commits)
powerpc/bug: Cast to unsigned long before passing to inline asm
powerpc/ptdump: Fix generic ptdump for 64-bit
KVM: PPC: Fix clearing never mapped TCEs in realmode
powerpc/pseries/iommu: Rename "direct window" to "dma window"
powerpc/pseries/iommu: Make use of DDW for indirect mapping
powerpc/pseries/iommu: Find existing DDW with given property name
powerpc/pseries/iommu: Update remove_dma_window() to accept property name
powerpc/pseries/iommu: Reorganize iommu_table_setparms*() with new helper
powerpc/pseries/iommu: Add ddw_property_create() and refactor enable_ddw()
powerpc/pseries/iommu: Allow DDW windows starting at 0x00
powerpc/pseries/iommu: Add ddw_list_new_entry() helper
powerpc/pseries/iommu: Add iommu_pseries_alloc_table() helper
powerpc/kernel/iommu: Add new iommu_table_in_use() helper
powerpc/pseries/iommu: Replace hard-coded page shift
powerpc/numa: Update cpu_cpu_map on CPU online/offline
powerpc/numa: Print debug statements only when required
powerpc/numa: convert printk to pr_xxx
powerpc/numa: Drop dbg in favour of pr_debug
powerpc/smp: Enable CACHE domain for shared processor
powerpc/smp: Update cpu_core_map on all PowerPc systems
...
Merge misc updates from Andrew Morton:
"173 patches.
Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
oom-kill, migration, ksm, percpu, vmstat, and madvise)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
mm/madvise: add MADV_WILLNEED to process_madvise()
mm/vmstat: remove unneeded return value
mm/vmstat: simplify the array size calculation
mm/vmstat: correct some wrong comments
mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
selftests: vm: add COW time test for KSM pages
selftests: vm: add KSM merging time test
mm: KSM: fix data type
selftests: vm: add KSM merging across nodes test
selftests: vm: add KSM zero page merging test
selftests: vm: add KSM unmerge test
selftests: vm: add KSM merge test
mm/migrate: correct kernel-doc notation
mm: wire up syscall process_mrelease
mm: introduce process_mrelease system call
memblock: make memblock_find_in_range method private
mm/mempolicy.c: use in_task() in mempolicy_slab_node()
mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
mm/mempolicy: advertise new MPOL_PREFERRED_MANY
mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
...
Since merged pages are copied every time they need to be modified, the
write access time is different between shared and non-shared pages. Add
ksm_cow_time() function which evaluates latency of these COW breaks.
First, 4000 pages are allocated and the time, required to modify 1 byte in
every other page, is measured. After this, the pages are merged into 2000
pairs and in each pair, 1 page is modified (i.e. they are decoupled) to
detect COW breaks. The time needed to break COW of merged pages is then
compared with performance of non-shared pages.
The test is run as follows: ./ksm_tests -C
The output:
Total size: 15 MiB
Not merged pages:
Total time: 0.002185489 s
Average speed: 3202.945 MiB/s
Merged pages:
Total time: 0.004386872 s
Average speed: 1595.670 MiB/s
Link: https://lkml.kernel.org/r/1d03ee0d1b341959d4b61672c6401d498bff5652.1629386192.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When userfaultfd copy-ioctl fails since the PTE already exists, an -EEXIST
error is returned and the faulting thread is not woken. The current
userfaultfd test does not wake the faulting thread in such case. The
assumption is presumably that another thread set the PTE through copy/wp
ioctl and would wake the faulting thread or that alternatively the fault
handler would realize there is no need to "must_wait" and continue. This
is not necessarily true.
There is an assumption that the "must_wait" tests in handle_userfault()
are sufficient to provide definitive answer whether the offending PTE is
populated or not. However, userfaultfd_must_wait() test is lockless.
Consequently, concurrent calls to ptep_modify_prot_start(), for instance,
can clear the PTE and can cause userfaultfd_must_wait() to wrongly assume
it is not populated and a wait is needed.
There are therefore 3 options:
(1) Change the tests to wake on copy failure.
(2) Wake faulting thread unconditionally on zero/copy ioctls before
returning -EEXIST.
(3) Change the userfaultfd_must_wait() to hold locks.
This patch took the first approach, but the others are valid solutions
with different tradeoffs.
Link: https://lkml.kernel.org/r/20210808020724.1022515-4-namit@vmware.com
Signed-off-by: Nadav Amit <namit@vmware.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>