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2102 commits

Author SHA1 Message Date
Alan Maguire
0f8619929c libbpf: Usdt aarch64 arg parsing support
Parsing of USDT arguments is architecture-specific. On aarch64 it is
relatively easy since registers used are x[0-31] and sp. Format is
slightly different compared to x86_64. Possible forms are:

- "size@[reg[,offset]]" for dereferences, e.g. "-8@[sp,76]" and "-4@[sp]";
- "size@reg" for register values, e.g. "-4@x0";
- "size@value" for raw values, e.g. "-8@1".

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1649690496-1902-2-git-send-email-alan.maguire@oracle.com
2022-04-11 15:32:28 -07:00
Runqing Yang
d252a4a499 libbpf: Fix a bug with checking bpf_probe_read_kernel() support in old kernels
Background:
Libbpf automatically replaces calls to BPF bpf_probe_read_{kernel,user}
[_str]() helpers with bpf_probe_read[_str](), if libbpf detects that
kernel doesn't support new APIs. Specifically, libbpf invokes the
probe_kern_probe_read_kernel function to load a small eBPF program into
the kernel in which bpf_probe_read_kernel API is invoked and lets the
kernel checks whether the new API is valid. If the loading fails, libbpf
considers the new API invalid and replaces it with the old API.

static int probe_kern_probe_read_kernel(void)
{
	struct bpf_insn insns[] = {
		BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),	/* r1 = r10 (fp) */
		BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),	/* r1 += -8 */
		BPF_MOV64_IMM(BPF_REG_2, 8),		/* r2 = 8 */
		BPF_MOV64_IMM(BPF_REG_3, 0),		/* r3 = 0 */
		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_probe_read_kernel),
		BPF_EXIT_INSN(),
	};
	int fd, insn_cnt = ARRAY_SIZE(insns);

	fd = bpf_prog_load(BPF_PROG_TYPE_KPROBE, NULL,
                           "GPL", insns, insn_cnt, NULL);
	return probe_fd(fd);
}

Bug:
On older kernel versions [0], the kernel checks whether the version
number provided in the bpf syscall, matches the LINUX_VERSION_CODE.
If not matched, the bpf syscall fails. eBPF However, the
probe_kern_probe_read_kernel code does not set the kernel version
number provided to the bpf syscall, which causes the loading process
alwasys fails for old versions. It means that libbpf will replace the
new API with the old one even the kernel supports the new one.

Solution:
After a discussion in [1], the solution is using BPF_PROG_TYPE_TRACEPOINT
program type instead of BPF_PROG_TYPE_KPROBE because kernel does not
enfoce version check for tracepoint programs. I test the patch in old
kernels (4.18 and 4.19) and it works well.

  [0] https://elixir.bootlin.com/linux/v4.19/source/kernel/bpf/syscall.c#L1360
  [1] Closes: https://github.com/libbpf/libbpf/issues/473

Signed-off-by: Runqing Yang <rainkin1993@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220409144928.27499-1-rainkin1993@gmail.com
2022-04-10 20:15:22 -07:00
Vladimir Isaev
0738599856 libbpf: Add ARC support to bpf_tracing.h
Add PT_REGS macros suitable for ARCompact and ARCv2.

Signed-off-by: Vladimir Isaev <isaev@synopsys.com>
Signed-off-by: Sergey Matyukevich <geomatsi@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220408224442.599566-1-geomatsi@gmail.com
2022-04-10 18:53:37 -07:00
Jakub Kicinski
34ba23b44c Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-04-09

We've added 63 non-merge commits during the last 9 day(s) which contain
a total of 68 files changed, 4852 insertions(+), 619 deletions(-).

The main changes are:

1) Add libbpf support for USDT (User Statically-Defined Tracing) probes.
   USDTs are an abstraction built on top of uprobes, critical for tracing
   and BPF, and widely used in production applications, from Andrii Nakryiko.

2) While Andrii was adding support for x86{-64}-specific logic of parsing
   USDT argument specification, Ilya followed-up with USDT support for s390
   architecture, from Ilya Leoshkevich.

3) Support name-based attaching for uprobe BPF programs in libbpf. The format
   supported is `u[ret]probe/binary_path:[raw_offset|function[+offset]]`, e.g.
   attaching to libc malloc can be done in BPF via SEC("uprobe/libc.so.6:malloc")
   now, from Alan Maguire.

4) Various load/store optimizations for the arm64 JIT to shrink the image
   size by using arm64 str/ldr immediate instructions. Also enable pointer
   authentication to verify return address for JITed code, from Xu Kuohai.

5) BPF verifier fixes for write access checks to helper functions, e.g.
   rd-only memory from bpf_*_cpu_ptr() must not be passed to helpers that
   write into passed buffers, from Kumar Kartikeya Dwivedi.

6) Fix overly excessive stack map allocation for its base map structure and
   buckets which slipped-in from cleanups during the rlimit accounting removal
   back then, from Yuntao Wang.

7) Extend the unstable CT lookup helpers for XDP and tc/BPF to report netfilter
   connection tracking tuple direction, from Lorenzo Bianconi.

8) Improve bpftool dump to show BPF program/link type names, Milan Landaverde.

9) Minor cleanups all over the place from various others.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (63 commits)
  bpf: Fix excessive memory allocation in stack_map_alloc()
  selftests/bpf: Fix return value checks in perf_event_stackmap test
  selftests/bpf: Add CO-RE relos into linked_funcs selftests
  libbpf: Use weak hidden modifier for USDT BPF-side API functions
  libbpf: Don't error out on CO-RE relos for overriden weak subprogs
  samples, bpf: Move routes monitor in xdp_router_ipv4 in a dedicated thread
  libbpf: Allow WEAK and GLOBAL bindings during BTF fixup
  libbpf: Use strlcpy() in path resolution fallback logic
  libbpf: Add s390-specific USDT arg spec parsing logic
  libbpf: Make BPF-side of USDT support work on big-endian machines
  libbpf: Minor style improvements in USDT code
  libbpf: Fix use #ifdef instead of #if to avoid compiler warning
  libbpf: Potential NULL dereference in usdt_manager_attach_usdt()
  selftests/bpf: Uprobe tests should verify param/return values
  libbpf: Improve string parsing for uprobe auto-attach
  libbpf: Improve library identification for uprobe binary path resolution
  selftests/bpf: Test for writes to map key from BPF helpers
  selftests/bpf: Test passing rdonly mem to global func
  bpf: Reject writes for PTR_TO_MAP_KEY in check_helper_mem_access
  bpf: Check PTR_TO_MEM | MEM_RDONLY in check_helper_mem_access
  ...
====================

Link: https://lore.kernel.org/r/20220408231741.19116-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-08 17:07:29 -07:00
Andrii Nakryiko
2fa5b0f290 libbpf: Use weak hidden modifier for USDT BPF-side API functions
Use __weak __hidden for bpf_usdt_xxx() APIs instead of much more
confusing `static inline __noinline`. This was previously impossible due
to libbpf erroring out on CO-RE relocations pointing to eliminated weak
subprogs. Now that previous patch fixed this issue, switch back to
__weak __hidden as it's a more direct way of specifying the desired
behavior.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220408181425.2287230-3-andrii@kernel.org
2022-04-08 22:24:15 +02:00
Andrii Nakryiko
e89d57d938 libbpf: Don't error out on CO-RE relos for overriden weak subprogs
During BPF static linking, all the ELF relocations and .BTF.ext
information (including CO-RE relocations) are preserved for __weak
subprograms that were logically overriden by either previous weak
subprogram instance or by corresponding "strong" (non-weak) subprogram.
This is just how native user-space linkers work, nothing new.

But libbpf is over-zealous when processing CO-RE relocation to error out
when CO-RE relocation belonging to such eliminated weak subprogram is
encountered. Instead of erroring out on this expected situation, log
debug-level message and skip the relocation.

Fixes: db2b8b0642 ("libbpf: Support CO-RE relocations for multi-prog sections")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220408181425.2287230-2-andrii@kernel.org
2022-04-08 22:24:15 +02:00
Andrii Nakryiko
3a06ec0a99 libbpf: Allow WEAK and GLOBAL bindings during BTF fixup
During BTF fix up for global variables, global variable can be global
weak and will have STB_WEAK binding in ELF. Support such global
variables in addition to non-weak ones.

This is not the problem when using BPF static linking, as BPF static
linker "fixes up" BTF during generation so that libbpf doesn't have to
do it anymore during bpf_object__open(), which led to this not being
noticed for a while, along with a pretty rare (currently) use of __weak
variables and maps.

Reported-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220407230446.3980075-2-andrii@kernel.org
2022-04-08 09:16:09 -07:00
Andrii Nakryiko
3c0dfe6e4c libbpf: Use strlcpy() in path resolution fallback logic
Coverity static analyzer complains that strcpy() can cause buffer
overflow. Use libbpf_strlcpy() instead to be 100% sure this doesn't
happen.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220407230446.3980075-1-andrii@kernel.org
2022-04-08 09:16:09 -07:00
Ilya Leoshkevich
bd022685bd libbpf: Add s390-specific USDT arg spec parsing logic
The logic is superficially similar to that of x86, but the small
differences (no need for register table and dynamic allocation of
register names, no $ sign before constants) make maintaining a common
implementation too burdensome. Therefore simply add a s390x-specific
version of parse_usdt_arg().

Note that while bcc supports index registers, this patch does not. This
should not be a problem in most cases, since s390 uses a default value
"nor" for STAP_SDT_ARG_CONSTRAINT.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220407214411.257260-4-iii@linux.ibm.com
2022-04-08 07:04:20 -07:00
Ilya Leoshkevich
6f403d9d53 libbpf: Make BPF-side of USDT support work on big-endian machines
BPF_USDT_ARG_REG_DEREF handling always reads 8 bytes, regardless of
the actual argument size. On little-endian the relevant argument bits
end up in the lower bits of val, and later on the code that handles
all the argument types expects them to be there.

On big-endian they end up in the upper bits of val, breaking that
expectation. Fix by right-shifting val on big-endian.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220407214411.257260-3-iii@linux.ibm.com
2022-04-07 20:59:10 -07:00
Ilya Leoshkevich
e1b6df598a libbpf: Minor style improvements in USDT code
Fix several typos and references to non-existing headers.
Also use __BYTE_ORDER__ instead of __BYTE_ORDER for consistency with
the rest of the bpf code - see commit 45f2bebc80 ("libbpf: Fix
endianness detection in BPF_CORE_READ_BITFIELD_PROBED()") for
rationale).

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220407214411.257260-2-iii@linux.ibm.com
2022-04-07 20:59:10 -07:00
Andrii Nakryiko
ded6dffaed libbpf: Fix use #ifdef instead of #if to avoid compiler warning
As reported by Naresh:

  perf build errors on i386 [1] on Linux next-20220407 [2]

  usdt.c:1181:5: error: "__x86_64__" is not defined, evaluates to 0
  [-Werror=undef]
   1181 | #if __x86_64__
        |     ^~~~~~~~~~
  usdt.c:1196:5: error: "__x86_64__" is not defined, evaluates to 0
  [-Werror=undef]
   1196 | #if __x86_64__
        |     ^~~~~~~~~~
  cc1: all warnings being treated as errors

Use #ifdef instead of #if to avoid this.

Fixes: 4c59e584d1 ("libbpf: Add x86-specific USDT arg spec parsing logic")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220407203842.3019904-1-andrii@kernel.org
2022-04-07 23:34:15 +02:00
Haowen Bai
e58c5c9717 libbpf: Potential NULL dereference in usdt_manager_attach_usdt()
link could be null but still dereference bpf_link__destroy(&link->link)
and it will lead to a null pointer access.

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1649299098-2069-1-git-send-email-baihaowen@meizu.com
2022-04-07 11:46:33 -07:00
Alan Maguire
90db26e6be libbpf: Improve string parsing for uprobe auto-attach
For uprobe auto-attach, the parsing can be simplified for the SEC()
name to a single sscanf(); the return value of the sscanf can then
be used to distinguish between sections that simply specify
"u[ret]probe" (and thus cannot auto-attach), those that specify
"u[ret]probe/binary_path:function+offset" etc.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1649245431-29956-3-git-send-email-alan.maguire@oracle.com
2022-04-07 11:42:50 -07:00
Alan Maguire
a1c9d61b19 libbpf: Improve library identification for uprobe binary path resolution
In the process of doing path resolution for uprobe attach, libraries are
identified by matching a ".so" substring in the binary_path.
This matches a lot of patterns that do not conform to library.so[.version]
format, so instead match a ".so" _suffix_, and if that fails match a
".so." substring for the versioned library case.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1649245431-29956-2-git-send-email-alan.maguire@oracle.com
2022-04-07 11:42:50 -07:00
Colin Ian King
a8d600f6bc libbpf: Fix spelling mistake "libaries" -> "libraries"
There is a spelling mistake in a pr_warn message. Fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220406080835.14879-1-colin.i.king@gmail.com
2022-04-06 10:14:27 -07:00
Andrii Nakryiko
4c59e584d1 libbpf: Add x86-specific USDT arg spec parsing logic
Add x86/x86_64-specific USDT argument specification parsing. Each
architecture will require their own logic, as all this is arch-specific
assembly-based notation. Architectures that libbpf doesn't support for
USDTs will pr_warn() with specific error and return -ENOTSUP.

We use sscanf() as a very powerful and easy to use string parser. Those
spaces in sscanf's format string mean "skip any whitespaces", which is
pretty nifty (and somewhat little known) feature.

All this was tested on little-endian architecture, so bit shifts are
probably off on big-endian, which our CI will hopefully prove.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/bpf/20220404234202.331384-6-andrii@kernel.org
2022-04-05 13:16:08 -07:00
Andrii Nakryiko
999783c8bb libbpf: Wire up spec management and other arch-independent USDT logic
Last part of architecture-agnostic user-space USDT handling logic is to
set up BPF spec and, optionally, IP-to-ID maps from user-space.
usdt_manager performs a compact spec ID allocation to utilize
fixed-sized BPF maps as efficiently as possible. We also use hashmap to
deduplicate USDT arg spec strings and map identical strings to single
USDT spec, minimizing the necessary BPF map size. usdt_manager supports
arbitrary sequences of attachment and detachment, both of the same USDT
and multiple different USDTs and internally maintains a free list of
unused spec IDs. bpf_link_usdt's logic is extended with proper setup and
teardown of this spec ID free list and supporting BPF maps.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/bpf/20220404234202.331384-5-andrii@kernel.org
2022-04-05 13:16:07 -07:00
Andrii Nakryiko
74cc6311ce libbpf: Add USDT notes parsing and resolution logic
Implement architecture-agnostic parts of USDT parsing logic. The code is
the documentation in this case, it's futile to try to succinctly
describe how USDT parsing is done in any sort of concreteness. But
still, USDTs are recorded in special ELF notes section (.note.stapsdt),
where each USDT call site is described separately. Along with USDT
provider and USDT name, each such note contains USDT argument
specification, which uses assembly-like syntax to describe how to fetch
value of USDT argument. USDT arg spec could be just a constant, or
a register, or a register dereference (most common cases in x86_64), but
it technically can be much more complicated cases, like offset relative
to global symbol and stuff like that. One of the later patches will
implement most common subset of this for x86 and x86-64 architectures,
which seems to handle a lot of real-world production application.

USDT arg spec contains a compact encoding allowing usdt.bpf.h from
previous patch to handle the above 3 cases. Instead of recording which
register might be needed, we encode register's offset within struct
pt_regs to simplify BPF-side implementation. USDT argument can be of
different byte sizes (1, 2, 4, and 8) and signed or unsigned. To handle
this, libbpf pre-calculates necessary bit shifts to do proper casting
and sign-extension in a short sequences of left and right shifts.

The rest is in the code with sometimes extensive comments and references
to external "documentation" for USDTs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/bpf/20220404234202.331384-4-andrii@kernel.org
2022-04-05 13:16:07 -07:00
Andrii Nakryiko
2e4913e025 libbpf: Wire up USDT API and bpf_link integration
Wire up libbpf USDT support APIs without yet implementing all the
nitty-gritty details of USDT discovery, spec parsing, and BPF map
initialization.

User-visible user-space API is simple and is conceptually very similar
to uprobe API.

bpf_program__attach_usdt() API allows to programmatically attach given
BPF program to a USDT, specified through binary path (executable or
shared lib), USDT provider and name. Also, just like in uprobe case, PID
filter is specified (0 - self, -1 - any process, or specific PID).
Optionally, USDT cookie value can be specified. Such single API
invocation will try to discover given USDT in specified binary and will
use (potentially many) BPF uprobes to attach this program in correct
locations.

Just like any bpf_program__attach_xxx() APIs, bpf_link is returned that
represents this attachment. It is a virtual BPF link that doesn't have
direct kernel object, as it can consist of multiple underlying BPF
uprobe links. As such, attachment is not atomic operation and there can
be brief moment when some USDT call sites are attached while others are
still in the process of attaching. This should be taken into
consideration by user. But bpf_program__attach_usdt() guarantees that
in the case of success all USDT call sites are successfully attached, or
all the successfuly attachments will be detached as soon as some USDT
call sites failed to be attached. So, in theory, there could be cases of
failed bpf_program__attach_usdt() call which did trigger few USDT
program invocations. This is unavoidable due to multi-uprobe nature of
USDT and has to be handled by user, if it's important to create an
illusion of atomicity.

USDT BPF programs themselves are marked in BPF source code as either
SEC("usdt"), in which case they won't be auto-attached through
skeleton's <skel>__attach() method, or it can have a full definition,
which follows the spirit of fully-specified uprobes:
SEC("usdt/<path>:<provider>:<name>"). In the latter case skeleton's
attach method will attempt auto-attachment. Similarly, generic
bpf_program__attach() will have enought information to go off of for
parameterless attachment.

USDT BPF programs are actually uprobes, and as such for kernel they are
marked as BPF_PROG_TYPE_KPROBE.

Another part of this patch is USDT-related feature probing:
  - BPF cookie support detection from user-space;
  - detection of kernel support for auto-refcounting of USDT semaphore.

The latter is optional. If kernel doesn't support such feature and USDT
doesn't rely on USDT semaphores, no error is returned. But if libbpf
detects that USDT requires setting semaphores and kernel doesn't support
this, libbpf errors out with explicit pr_warn() message. Libbpf doesn't
support poking process's memory directly to increment semaphore value,
like BCC does on legacy kernels, due to inherent raciness and danger of
such process memory manipulation. Libbpf let's kernel take care of this
properly or gives up.

Logistically, all the extra USDT-related infrastructure of libbpf is put
into a separate usdt.c file and abstracted behind struct usdt_manager.
Each bpf_object has lazily-initialized usdt_manager pointer, which is
only instantiated if USDT programs are attempted to be attached. Closing
BPF object frees up usdt_manager resources. usdt_manager keeps track of
USDT spec ID assignment and few other small things.

Subsequent patches will fill out remaining missing pieces of USDT
initialization and setup logic.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20220404234202.331384-3-andrii@kernel.org
2022-04-05 13:16:07 -07:00
Andrii Nakryiko
d72e2968fb libbpf: Add BPF-side of USDT support
Add BPF-side implementation of libbpf-provided USDT support. This
consists of single header library, usdt.bpf.h, which is meant to be used
from user's BPF-side source code. This header is added to the list of
installed libbpf header, along bpf_helpers.h and others.

BPF-side implementation consists of two BPF maps:
  - spec map, which contains "a USDT spec" which encodes information
    necessary to be able to fetch USDT arguments and other information
    (argument count, user-provided cookie value, etc) at runtime;
  - IP-to-spec-ID map, which is only used on kernels that don't support
    BPF cookie feature. It allows to lookup spec ID based on the place
    in user application that triggers USDT program.

These maps have default sizes, 256 and 1024, which are chosen
conservatively to not waste a lot of space, but handling a lot of common
cases. But there could be cases when user application needs to either
trace a lot of different USDTs, or USDTs are heavily inlined and their
arguments are located in a lot of differing locations. For such cases it
might be necessary to size those maps up, which libbpf allows to do by
overriding BPF_USDT_MAX_SPEC_CNT and BPF_USDT_MAX_IP_CNT macros.

It is an important aspect to keep in mind. Single USDT (user-space
equivalent of kernel tracepoint) can have multiple USDT "call sites".
That is, single logical USDT is triggered from multiple places in user
application. This can happen due to function inlining. Each such inlined
instance of USDT invocation can have its own unique USDT argument
specification (instructions about the location of the value of each of
USDT arguments). So while USDT looks very similar to usual uprobe or
kernel tracepoint, under the hood it's actually a collection of uprobes,
each potentially needing different spec to know how to fetch arguments.

User-visible API consists of three helper functions:
  - bpf_usdt_arg_cnt(), which returns number of arguments of current USDT;
  - bpf_usdt_arg(), which reads value of specified USDT argument (by
    it's zero-indexed position) and returns it as 64-bit value;
  - bpf_usdt_cookie(), which functions like BPF cookie for USDT
    programs; this is necessary as libbpf doesn't allow specifying actual
    BPF cookie and utilizes it internally for USDT support implementation.

Each bpf_usdt_xxx() APIs expect struct pt_regs * context, passed into
BPF program. On kernels that don't support BPF cookie it is used to
fetch absolute IP address of the underlying uprobe.

usdt.bpf.h also provides BPF_USDT() macro, which functions like
BPF_PROG() and BPF_KPROBE() and allows much more user-friendly way to
get access to USDT arguments, if USDT definition is static and known to
the user. It is expected that majority of use cases won't have to use
bpf_usdt_arg_cnt() and bpf_usdt_arg() directly and BPF_USDT() will cover
all their needs.

Last, usdt.bpf.h is utilizing BPF CO-RE for one single purpose: to
detect kernel support for BPF cookie. If BPF CO-RE dependency is
undesirable, user application can redefine BPF_USDT_HAS_BPF_COOKIE to
either a boolean constant (or equivalently zero and non-zero), or even
point it to its own .rodata variable that can be specified from user's
application user-space code. It is important that
BPF_USDT_HAS_BPF_COOKIE is known to BPF verifier as static value (thus
.rodata and not just .data), as otherwise BPF code will still contain
bpf_get_attach_cookie() BPF helper call and will fail validation at
runtime, if not dead-code eliminated.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20220404234202.331384-2-andrii@kernel.org
2022-04-05 13:16:07 -07:00
Ilya Leoshkevich
568189310c libbpf: Support Debian in resolve_full_path()
attach_probe selftest fails on Debian-based distros with `failed to
resolve full path for 'libc.so.6'`. The reason is that these distros
embraced multiarch to the point where even for the "main" architecture
they store libc in /lib/<triple>.

This is configured in /etc/ld.so.conf and in theory it's possible to
replicate the loader's parsing and processing logic in libbpf, however
a much simpler solution is to just enumerate the known library paths.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220404225020.51029-1-iii@linux.ibm.com
2022-04-04 16:47:16 -07:00
Yuntao Wang
e93f39998d libbpf: Don't return -EINVAL if hdr_len < offsetofend(core_relo_len)
Since core relos is an optional part of the .BTF.ext ELF section, we should
skip parsing it instead of returning -EINVAL if header size is less than
offsetofend(struct btf_ext_header, core_relo_len).

Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220404005320.1723055-1-ytcoode@gmail.com
2022-04-03 19:56:01 -07:00
Alan Maguire
39f8dc43b7 libbpf: Add auto-attach for uprobes based on section name
Now that u[ret]probes can use name-based specification, it makes
sense to add support for auto-attach based on SEC() definition.
The format proposed is

        SEC("u[ret]probe/binary:[raw_offset|[function_name[+offset]]")

For example, to trace malloc() in libc:

        SEC("uprobe/libc.so.6:malloc")

...or to trace function foo2 in /usr/bin/foo:

        SEC("uprobe//usr/bin/foo:foo2")

Auto-attach is done for all tasks (pid -1).  prog can be an absolute
path or simply a program/library name; in the latter case, we use
PATH/LD_LIBRARY_PATH to resolve the full path, falling back to
standard locations (/usr/bin:/usr/sbin or /usr/lib64:/usr/lib) if
the file is not found via environment-variable specified locations.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1648654000-21758-4-git-send-email-alan.maguire@oracle.com
2022-04-03 19:55:57 -07:00
Alan Maguire
433966e3ae libbpf: Support function name-based attach uprobes
kprobe attach is name-based, using lookups of kallsyms to translate
a function name to an address.  Currently uprobe attach is done
via an offset value as described in [1].  Extend uprobe opts
for attach to include a function name which can then be converted
into a uprobe-friendly offset.  The calcualation is done in
several steps:

1. First, determine the symbol address using libelf; this gives us
   the offset as reported by objdump
2. If the function is a shared library function - and the binary
   provided is a shared library - no further work is required;
   the address found is the required address
3. Finally, if the function is local, subtract the base address
   associated with the object, retrieved from ELF program headers.

The resultant value is then added to the func_offset value passed
in to specify the uprobe attach address.  So specifying a func_offset
of 0 along with a function name "printf" will attach to printf entry.

The modes of operation supported are then

1. to attach to a local function in a binary; function "foo1" in
   "/usr/bin/foo"
2. to attach to a shared library function in a shared library -
   function "malloc" in libc.

[1] https://www.kernel.org/doc/html/latest/trace/uprobetracer.html

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1648654000-21758-3-git-send-email-alan.maguire@oracle.com
2022-04-03 18:12:05 -07:00
Alan Maguire
1ce3a60e3c libbpf: auto-resolve programs/libraries when necessary for uprobes
bpf_program__attach_uprobe_opts() requires a binary_path argument
specifying binary to instrument.  Supporting simply specifying
"libc.so.6" or "foo" should be possible too.

Library search checks LD_LIBRARY_PATH, then /usr/lib64, /usr/lib.
This allows users to run BPF programs prefixed with
LD_LIBRARY_PATH=/path2/lib while still searching standard locations.
Similarly for non .so files, we check PATH and /usr/bin, /usr/sbin.

Path determination will be useful for auto-attach of BPF uprobe programs
using SEC() definition.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1648654000-21758-2-git-send-email-alan.maguire@oracle.com
2022-04-03 18:11:47 -07:00
Ian Rogers
da0bfb9fdf perf cpumap: More cpu map reuse by merge.
perf_cpu_map__merge() will reuse one of its arguments if they are equal or
the other argument is NULL.

The arguments could be reused if it is known one set of values is a
subset of the other.

For example, a map of 0-1 and a map of just 0 when merged yields the map
of 0-1.

Currently a new map is created rather than adding a reference count to
the original 0-1 map.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Antonov <alexander.antonov@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: German Gomez <german.gomez@arm.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: John Garry <john.garry@huawei.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220328232648.2127340-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-04-01 16:19:35 -03:00
Ian Rogers
c3ad8d23bc perf cpumap: Add is_subset function
Returns true if the second argument is a subset of the first.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Antonov <alexander.antonov@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: German Gomez <german.gomez@arm.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: John Garry <john.garry@huawei.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220328232648.2127340-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-04-01 16:19:35 -03:00
Ian Rogers
0df6ade711 perf evlist: Rename cpus to user_requested_cpus
evlist contains cpus and all_cpus. all_cpus is the union of the cpu maps
of all evsels.

For non-task targets, cpus is set to be cpus requested from the command
line, defaulting to all online cpus if no cpus are specified.

For an uncore event, all_cpus may be just CPU 0 or every online CPU.

This causes all_cpus to have fewer values than the cpus variable which
is confusing given the 'all' in the name.

To try to make the behavior clearer, rename cpus to user_requested_cpus
and add comments on the two struct variables.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Antonov <alexander.antonov@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: German Gomez <german.gomez@arm.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: John Garry <john.garry@huawei.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220328232648.2127340-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-04-01 16:19:35 -03:00
Linus Torvalds
b8321ed4a4 Kbuild updates for v5.18
- Add new environment variables, USERCFLAGS and USERLDFLAGS to allow
    additional flags to be passed to user-space programs.
 
  - Fix missing fflush() bugs in Kconfig and fixdep
 
  - Fix a minor bug in the comment format of the .config file
 
  - Make kallsyms ignore llvm's local labels, .L*
 
  - Fix UAPI compile-test for cross-compiling with Clang
 
  - Extend the LLVM= syntax to support LLVM=<suffix> form for using a
    particular version of LLVm, and LLVM=<prefix> form for using custom
    LLVM in a particular directory path.
 
  - Clean up Makefiles
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Merge tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Add new environment variables, USERCFLAGS and USERLDFLAGS to allow
   additional flags to be passed to user-space programs.

 - Fix missing fflush() bugs in Kconfig and fixdep

 - Fix a minor bug in the comment format of the .config file

 - Make kallsyms ignore llvm's local labels, .L*

 - Fix UAPI compile-test for cross-compiling with Clang

 - Extend the LLVM= syntax to support LLVM=<suffix> form for using a
   particular version of LLVm, and LLVM=<prefix> form for using custom
   LLVM in a particular directory path.

 - Clean up Makefiles

* tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: Make $(LLVM) more flexible
  kbuild: add --target to correctly cross-compile UAPI headers with Clang
  fixdep: use fflush() and ferror() to ensure successful write to files
  arch: syscalls: simplify uapi/kapi directory creation
  usr/include: replace extra-y with always-y
  certs: simplify empty certs creation in certs/Makefile
  certs: include certs/signing_key.x509 unconditionally
  kallsyms: ignore all local labels prefixed by '.L'
  kconfig: fix missing '# end of' for empty menu
  kconfig: add fflush() before ferror() check
  kbuild: replace $(if A,A,B) with $(or A,B)
  kbuild: Add environment variables for userprogs flags
  kbuild: unify cmd_copy and cmd_shipped
2022-03-31 11:59:03 -07:00
Linus Torvalds
7b58b82b86 perf tools changes for v5.18: 1st batch
New features:
 
 perf ftrace:
 
 - Add -n/--use-nsec option to the 'latency' subcommand.
 
   Default: usecs:
 
   $ sudo perf ftrace latency -T dput -a sleep 1
   #   DURATION     |      COUNT | GRAPH                          |
        0 - 1    us |    2098375 | #############################  |
        1 - 2    us |         61 |                                |
        2 - 4    us |         33 |                                |
        4 - 8    us |         13 |                                |
        8 - 16   us |        124 |                                |
       16 - 32   us |        123 |                                |
       32 - 64   us |          1 |                                |
       64 - 128  us |          0 |                                |
      128 - 256  us |          1 |                                |
      256 - 512  us |          0 |                                |
 
   Better granularity with nsec:
 
   $ sudo perf ftrace latency -T dput -a -n sleep 1
   #   DURATION     |      COUNT | GRAPH                          |
        0 - 1    us |          0 |                                |
        1 - 2    ns |          0 |                                |
        2 - 4    ns |          0 |                                |
        4 - 8    ns |          0 |                                |
        8 - 16   ns |          0 |                                |
       16 - 32   ns |          0 |                                |
       32 - 64   ns |          0 |                                |
       64 - 128  ns |    1163434 | ##############                 |
      128 - 256  ns |     914102 | #############                  |
      256 - 512  ns |        884 |                                |
      512 - 1024 ns |        613 |                                |
        1 - 2    us |         31 |                                |
        2 - 4    us |         17 |                                |
        4 - 8    us |          7 |                                |
        8 - 16   us |        123 |                                |
       16 - 32   us |         83 |                                |
 
 perf lock:
 
 - Add -c/--combine-locks option to merge lock instances in the same class into
   a single entry.
 
   # perf lock report -c
                  Name acquired contended avg wait(ns) total wait(ns) max wait(ns) min wait(ns)
 
         rcu_read_lock   251225         0            0              0            0            0
    hrtimer_bases.lock    39450         0            0              0            0            0
   &sb->s_type->i_l...    10301         1          662            662          662          662
      ptlock_ptr(page)    10173         2          701           1402          760          642
   &(ei->i_block_re...     8732         0            0              0            0            0
          &xa->xa_lock     8088         0            0              0            0            0
           &base->lock     6705         0            0              0            0            0
           &p->pi_lock     5549         0            0              0            0            0
   &dentry->d_lockr...     5010         4         1274           5097         1844          789
             &ep->lock     3958         0            0              0            0            0
 
 - Add -F/--field option to customize the list of fields to output:
 
   $ perf lock report -F contended,wait_max -k avg_wait
                   Name contended max wait(ns) avg wait(ns)
 
         slock-AF_INET6         1        23543        23543
      &lruvec->lru_lock         5        18317        11254
         slock-AF_INET6         1        10379        10379
             rcu_node_1         1         2104         2104
    &dentry->d_lockr...         1         1844         1844
    &dentry->d_lockr...         1         1672         1672
       &newf->file_lock        15         2279         1025
    &dentry->d_lockr...         1          792          792
 
 - Add --synth=no option for record, as there is no need to symbolize,
   lock names comes from the tracepoints.
 
 perf record:
 
 - Threaded recording, opt-in, via the new --threads command line option.
 
 - Improve AMD IBS (Instruction-Based Sampling) error handling messages.
 
 perf script:
 
 - Add 'brstackinsnlen' field (use it with -F) for branch stacks.
 
 - Output branch sample type in 'perf script'.
 
 perf report:
 
 - Add "addr_from" and "addr_to" sort dimensions.
 
 - Print branch stack entry type in 'perf report --dump-raw-trace'
 
 - Fix symbolization for chrooted workloads.
 
 Hardware tracing:
 
 Intel PT:
 
 - Add CFE (Control Flow Event) and EVD (Event Data) packets support.
 
 - Add MODE.Exec IFLAG bit support.
 
 Explanation about these features from the "Intel® 64 and IA-32 architectures
 software developer’s manual combined volumes: 1, 2A, 2B, 2C, 2D, 3A, 3B, 3C,
 3D, and 4" PDF at:
 
   https://cdrdv2.intel.com/v1/dl/getContent/671200
 
 At page 3951:
 
 <quote>
 32.2.4
 
 Event Trace is a capability that exposes details about the asynchronous
 events, when they are generated, and when their corresponding software
 event handler completes execution. These include:
 
 o Interrupts, including NMI and SMI, including the interrupt vector when
 defined.
 
 o Faults, exceptions including the fault vector.
 
 — Page faults additionally include the page fault address, when in context.
 
 o Event handler returns, including IRET and RSM.
 
 o VM exits and VM entries.¹
 
 — VM exits include the values written to the “exit reason” and “exit qualification” VMCS fields.
 INIT and SIPI events.
 
 o TSX aborts, including the abort status returned for the RTM instructions.
 
 o Shutdown.
 
 Additionally, it provides indication of the status of the Interrupt Flag
 (IF), to indicate when interrupts are masked.
 </quote>
 
 ARM CoreSight:
 
 - Use advertised caps/min_interval as default sample_period on ARM spe.
 
 - Update deduction of TRCCONFIGR register for branch broadcast on ARM's CoreSight ETM.
 
 Vendor Events (JSON):
 
 Intel:
 
 - Update events and metrics for:
 
     Alderlake, Broadwell, Broadwell DE, BroadwellX, CascadelakeX, Elkhartlake,
     Bonnell, Goldmont, GoldmontPlus, Westmere EP-DP, Haswell, HaswellX,
     Icelake, IcelakeX, Ivybridge, Ivytown, Jaketown, Knights Landing,
     Nehalem EP, Sandybridge, Silvermont, Skylake, Skylake Server, SkylakeX,
     Tigerlake, TremontX, Westmere EP-SP, Westmere EX.
 
 ARM:
 
 - Add support for HiSilicon CPA PMU aliasing.
 
 perf stat:
 
 - Fix forked applications enablement of counters.
 
 - The 'slots' should only be printed on a different order than the one specified
   on the command line when 'topdown' events are present, fix it.
 
 Miscellaneous:
 
 - Sync msr-index, cpufeatures header files with the kernel sources.
 
 - Stop using some deprecated libbpf APIs in 'perf trace'.
 
 - Fix some spelling mistakes.
 
 - Refactor the maps pointers usage to pave the way for using refcount debugging.
 
 - Only offer the --tui option on perf top, report and annotate when perf was
   built with libslang.
 
 - Don't mention --to-ctf in 'perf data --help' when not linking with the required
   library, libbabeltrace.
 
 - Use ARRAY_SIZE() instead of ad hoc equivalent, spotted by array_size.cocci.
 
 - Enhance the matching of sub-commands abbreviations:
 	'perf c2c rec' -> 'perf c2c record'
 	'perf c2c recport -> error
 
 - Set build-id using build-id header on new mmap records.
 
 - Fix generation of 'perf --version' string.
 
 perf test:
 
 - Add test for the arm_spe event.
 
 - Add test to check unwinding using fame-pointer (fp) mode on arm64.
 
 - Make metric testing more robust in 'perf test'.
 
 - Add error message for unsupported branch stack cases.
 
 libperf:
 
 - Add API for allocating new thread map array.
 
 - Fix typo in perf_evlist__open() failure error messages in libperf tests.
 
 perf c2c:
 
 - Replace bitmap_weight() with bitmap_empty() where appropriate.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v5.18-2022-03-26' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tools updates from Arnaldo Carvalho de Melo:
 "New features:

  perf ftrace:

   - Add -n/--use-nsec option to the 'latency' subcommand.

     Default: usecs:

     $ sudo perf ftrace latency -T dput -a sleep 1
     #   DURATION     |      COUNT | GRAPH                          |
          0 - 1    us |    2098375 | #############################  |
          1 - 2    us |         61 |                                |
          2 - 4    us |         33 |                                |
          4 - 8    us |         13 |                                |
          8 - 16   us |        124 |                                |
         16 - 32   us |        123 |                                |
         32 - 64   us |          1 |                                |
         64 - 128  us |          0 |                                |
        128 - 256  us |          1 |                                |
        256 - 512  us |          0 |                                |

     Better granularity with nsec:

     $ sudo perf ftrace latency -T dput -a -n sleep 1
     #   DURATION     |      COUNT | GRAPH                          |
          0 - 1    us |          0 |                                |
          1 - 2    ns |          0 |                                |
          2 - 4    ns |          0 |                                |
          4 - 8    ns |          0 |                                |
          8 - 16   ns |          0 |                                |
         16 - 32   ns |          0 |                                |
         32 - 64   ns |          0 |                                |
         64 - 128  ns |    1163434 | ##############                 |
        128 - 256  ns |     914102 | #############                  |
        256 - 512  ns |        884 |                                |
        512 - 1024 ns |        613 |                                |
          1 - 2    us |         31 |                                |
          2 - 4    us |         17 |                                |
          4 - 8    us |          7 |                                |
          8 - 16   us |        123 |                                |
         16 - 32   us |         83 |                                |

  perf lock:

   - Add -c/--combine-locks option to merge lock instances in the same
     class into a single entry.

     # perf lock report -c
                    Name acquired contended avg wait(ns) total wait(ns) max wait(ns) min wait(ns)

           rcu_read_lock   251225         0            0              0            0            0
      hrtimer_bases.lock    39450         0            0              0            0            0
     &sb->s_type->i_l...    10301         1          662            662          662          662
        ptlock_ptr(page)    10173         2          701           1402          760          642
     &(ei->i_block_re...     8732         0            0              0            0            0
            &xa->xa_lock     8088         0            0              0            0            0
             &base->lock     6705         0            0              0            0            0
             &p->pi_lock     5549         0            0              0            0            0
     &dentry->d_lockr...     5010         4         1274           5097         1844          789
               &ep->lock     3958         0            0              0            0            0

      - Add -F/--field option to customize the list of fields to output:

     $ perf lock report -F contended,wait_max -k avg_wait
                     Name contended max wait(ns) avg wait(ns)

           slock-AF_INET6         1        23543        23543
        &lruvec->lru_lock         5        18317        11254
           slock-AF_INET6         1        10379        10379
               rcu_node_1         1         2104         2104
      &dentry->d_lockr...         1         1844         1844
      &dentry->d_lockr...         1         1672         1672
         &newf->file_lock        15         2279         1025
      &dentry->d_lockr...         1          792          792

   - Add --synth=no option for record, as there is no need to symbolize,
     lock names comes from the tracepoints.

  perf record:

   - Threaded recording, opt-in, via the new --threads command line
     option.

   - Improve AMD IBS (Instruction-Based Sampling) error handling
     messages.

  perf script:

   - Add 'brstackinsnlen' field (use it with -F) for branch stacks.

   - Output branch sample type in 'perf script'.

  perf report:

   - Add "addr_from" and "addr_to" sort dimensions.

   - Print branch stack entry type in 'perf report --dump-raw-trace'

   - Fix symbolization for chrooted workloads.

  Hardware tracing:

  Intel PT:

   - Add CFE (Control Flow Event) and EVD (Event Data) packets support.

   - Add MODE.Exec IFLAG bit support.

     Explanation about these features from the "Intel® 64 and IA-32
     architectures software developer’s manual combined volumes: 1, 2A,
     2B, 2C, 2D, 3A, 3B, 3C, 3D, and 4" PDF at:

        https://cdrdv2.intel.com/v1/dl/getContent/671200

     At page 3951:
      "32.2.4

       Event Trace is a capability that exposes details about the
       asynchronous events, when they are generated, and when their
       corresponding software event handler completes execution. These
       include:

        o Interrupts, including NMI and SMI, including the interrupt
          vector when defined.

        o Faults, exceptions including the fault vector.

           - Page faults additionally include the page fault address,
             when in context.

        o Event handler returns, including IRET and RSM.

        o VM exits and VM entries.¹

           - VM exits include the values written to the “exit reason”
             and “exit qualification” VMCS fields. INIT and SIPI events.

        o TSX aborts, including the abort status returned for the RTM
          instructions.

        o Shutdown.

       Additionally, it provides indication of the status of the
       Interrupt Flag (IF), to indicate when interrupts are masked"

  ARM CoreSight:

   - Use advertised caps/min_interval as default sample_period on ARM
     spe.

   - Update deduction of TRCCONFIGR register for branch broadcast on
     ARM's CoreSight ETM.

  Vendor Events (JSON):

  Intel:

   - Update events and metrics for: Alderlake, Broadwell, Broadwell DE,
     BroadwellX, CascadelakeX, Elkhartlake, Bonnell, Goldmont,
     GoldmontPlus, Westmere EP-DP, Haswell, HaswellX, Icelake, IcelakeX,
     Ivybridge, Ivytown, Jaketown, Knights Landing, Nehalem EP,
     Sandybridge, Silvermont, Skylake, Skylake Server, SkylakeX,
     Tigerlake, TremontX, Westmere EP-SP, and Westmere EX.

  ARM:

   - Add support for HiSilicon CPA PMU aliasing.

  perf stat:

   - Fix forked applications enablement of counters.

   - The 'slots' should only be printed on a different order than the
     one specified on the command line when 'topdown' events are
     present, fix it.

  Miscellaneous:

   - Sync msr-index, cpufeatures header files with the kernel sources.

   - Stop using some deprecated libbpf APIs in 'perf trace'.

   - Fix some spelling mistakes.

   - Refactor the maps pointers usage to pave the way for using refcount
     debugging.

   - Only offer the --tui option on perf top, report and annotate when
     perf was built with libslang.

   - Don't mention --to-ctf in 'perf data --help' when not linking with
     the required library, libbabeltrace.

   - Use ARRAY_SIZE() instead of ad hoc equivalent, spotted by
     array_size.cocci.

   - Enhance the matching of sub-commands abbreviations:
	'perf c2c rec' -> 'perf c2c record'
	'perf c2c recport -> error

   - Set build-id using build-id header on new mmap records.

   - Fix generation of 'perf --version' string.

  perf test:

   - Add test for the arm_spe event.

   - Add test to check unwinding using fame-pointer (fp) mode on arm64.

   - Make metric testing more robust in 'perf test'.

   - Add error message for unsupported branch stack cases.

  libperf:

   - Add API for allocating new thread map array.

   - Fix typo in perf_evlist__open() failure error messages in libperf
     tests.

  perf c2c:

   - Replace bitmap_weight() with bitmap_empty() where appropriate"

* tag 'perf-tools-for-v5.18-2022-03-26' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (143 commits)
  perf evsel: Improve AMD IBS (Instruction-Based Sampling) error handling messages
  perf python: Add perf_env stubs that will be needed in evsel__open_strerror()
  perf tools: Enhance the matching of sub-commands abbreviations
  libperf tests: Fix typo in perf_evlist__open() failure error messages
  tools arm64: Import cputype.h
  perf lock: Add -F/--field option to control output
  perf lock: Extend struct lock_key to have print function
  perf lock: Add --synth=no option for record
  tools headers cpufeatures: Sync with the kernel sources
  tools headers cpufeatures: Sync with the kernel sources
  perf stat: Fix forked applications enablement of counters
  tools arch x86: Sync the msr-index.h copy with the kernel sources
  perf evsel: Make evsel__env() always return a valid env
  perf build-id: Fix spelling mistake "Cant" -> "Can't"
  perf header: Fix spelling mistake "could't" -> "couldn't"
  perf script: Add 'brstackinsnlen' for branch stacks
  perf parse-events: Move slots only with topdown
  perf ftrace latency: Update documentation
  perf ftrace latency: Add -n/--use-nsec option
  perf tools: Fix version kernel tag
  ...
2022-03-27 13:42:32 -07:00
Linus Torvalds
02f9a04d76 memblock: test suite and a small cleanup
* A small cleanup of unused variable in __next_mem_pfn_range_in_zone
 * Initial test suite to simulate memblock behaviour in userspace
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Merge tag 'memblock-v5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock

Pull memblock updates from Mike Rapoport:
 "Test suite and a small cleanup:

   - A small cleanup of unused variable in __next_mem_pfn_range_in_zone

   - Initial test suite to simulate memblock behaviour in userspace"

* tag 'memblock-v5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock: (27 commits)
  memblock tests: Add TODO and README files
  memblock tests: Add memblock_alloc_try_nid tests for bottom up
  memblock tests: Add memblock_alloc_try_nid tests for top down
  memblock tests: Add memblock_alloc_from tests for bottom up
  memblock tests: Add memblock_alloc_from tests for top down
  memblock tests: Add memblock_alloc tests for bottom up
  memblock tests: Add memblock_alloc tests for top down
  memblock tests: Add simulation of physical memory
  memblock tests: Split up reset_memblock function
  memblock tests: Fix testing with 32-bit physical addresses
  memblock: __next_mem_pfn_range_in_zone: remove unneeded local variable nid
  memblock tests: Add memblock_free tests
  memblock tests: Add memblock_add_node test
  memblock tests: Add memblock_remove tests
  memblock tests: Add memblock_reserve tests
  memblock tests: Add memblock_add tests
  memblock tests: Add memblock reset function
  memblock tests: Add skeleton of the memblock simulator
  tools/include: Add debugfs.h stub
  tools/include: Add pfn.h stub
  ...
2022-03-27 13:36:06 -07:00
Shunsuke Nakamura
c2eeac9856 libperf tests: Fix typo in perf_evlist__open() failure error messages
This patch corrects typos in error messages. I should be "evlist", not
"evsel" as the function that fails is perf_evlist__open().

Fixes: 3ce311afb5 ("libperf: Move to tools/lib/perf")
Fixes: a7f3713f6b ("libperf tests: Add test_stat_multiplexing test")
Signed-off-by: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20220325043829.224045-2-nakamura.shun@fujitsu.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-03-26 10:55:57 -03:00
Linus Torvalds
169e77764a Networking changes for 5.18.
Core
 ----
 
  - Introduce XDP multi-buffer support, allowing the use of XDP with
    jumbo frame MTUs and combination with Rx coalescing offloads (LRO).
 
  - Speed up netns dismantling (5x) and lower the memory cost a little.
    Remove unnecessary per-netns sockets. Scope some lists to a netns.
    Cut down RCU syncing. Use batch methods. Allow netdev registration
    to complete out of order.
 
  - Support distinguishing timestamp types (ingress vs egress) and
    maintaining them across packet scrubbing points (e.g. redirect).
 
  - Continue the work of annotating packet drop reasons throughout
    the stack.
 
  - Switch netdev error counters from an atomic to dynamically
    allocated per-CPU counters.
 
  - Rework a few preempt_disable(), local_irq_save() and busy waiting
    sections problematic on PREEMPT_RT.
 
  - Extend the ref_tracker to allow catching use-after-free bugs.
 
 BPF
 ---
 
  - Introduce "packing allocator" for BPF JIT images. JITed code is
    marked read only, and used to be allocated at page granularity.
    Custom allocator allows for more efficient memory use, lower
    iTLB pressure and prevents identity mapping huge pages from
    getting split.
 
  - Make use of BTF type annotations (e.g. __user, __percpu) to enforce
    the correct probe read access method, add appropriate helpers.
 
  - Convert the BPF preload to use light skeleton and drop
    the user-mode-driver dependency.
 
  - Allow XDP BPF_PROG_RUN test infra to send real packets, enabling
    its use as a packet generator.
 
  - Allow local storage memory to be allocated with GFP_KERNEL if called
    from a hook allowed to sleep.
 
  - Introduce fprobe (multi kprobe) to speed up mass attachment (arch
    bits to come later).
 
  - Add unstable conntrack lookup helpers for BPF by using the BPF
    kfunc infra.
 
  - Allow cgroup BPF progs to return custom errors to user space.
 
  - Add support for AF_UNIX iterator batching.
 
  - Allow iterator programs to use sleepable helpers.
 
  - Support JIT of add, and, or, xor and xchg atomic ops on arm64.
 
  - Add BTFGen support to bpftool which allows to use CO-RE in kernels
    without BTF info.
 
  - Large number of libbpf API improvements, cleanups and deprecations.
 
 Protocols
 ---------
 
  - Micro-optimize UDPv6 Tx, gaining up to 5% in test on dummy netdev.
 
  - Adjust TSO packet sizes based on min_rtt, allowing very low latency
    links (data centers) to always send full-sized TSO super-frames.
 
  - Make IPv6 flow label changes (AKA hash rethink) more configurable,
    via sysctl and setsockopt. Distinguish between server and client
    behavior.
 
  - VxLAN support to "collect metadata" devices to terminate only
    configured VNIs. This is similar to VLAN filtering in the bridge.
 
  - Support inserting IPv6 IOAM information to a fraction of frames.
 
  - Add protocol attribute to IP addresses to allow identifying where
    given address comes from (kernel-generated, DHCP etc.)
 
  - Support setting socket and IPv6 options via cmsg on ping6 sockets.
 
  - Reject mis-use of ECN bits in IP headers as part of DSCP/TOS.
    Define dscp_t and stop taking ECN bits into account in fib-rules.
 
  - Add support for locked bridge ports (for 802.1X).
 
  - tun: support NAPI for packets received from batched XDP buffs,
    doubling the performance in some scenarios.
 
  - IPv6 extension header handling in Open vSwitch.
 
  - Support IPv6 control message load balancing in bonding, prevent
    neighbor solicitation and advertisement from using the wrong port.
    Support NS/NA monitor selection similar to existing ARP monitor.
 
  - SMC
    - improve performance with TCP_CORK and sendfile()
    - support auto-corking
    - support TCP_NODELAY
 
  - MCTP (Management Component Transport Protocol)
    - add user space tag control interface
    - I2C binding driver (as specified by DMTF DSP0237)
 
  - Multi-BSSID beacon handling in AP mode for WiFi.
 
  - Bluetooth:
    - handle MSFT Monitor Device Event
    - add MGMT Adv Monitor Device Found/Lost events
 
  - Multi-Path TCP:
    - add support for the SO_SNDTIMEO socket option
    - lots of selftest cleanups and improvements
 
  - Increase the max PDU size in CAN ISOTP to 64 kB.
 
 Driver API
 ----------
 
  - Add HW counters for SW netdevs, a mechanism for devices which
    offload packet forwarding to report packet statistics back to
    software interfaces such as tunnels.
 
  - Select the default NIC queue count as a fraction of number of
    physical CPU cores, instead of hard-coding to 8.
 
  - Expose devlink instance locks to drivers. Allow device layer of
    drivers to use that lock directly instead of creating their own
    which always runs into ordering issues in devlink callbacks.
 
  - Add header/data split indication to guide user space enabling
    of TCP zero-copy Rx.
 
  - Allow configuring completion queue event size.
 
  - Refactor page_pool to enable fragmenting after allocation.
 
  - Add allocation and page reuse statistics to page_pool.
 
  - Improve Multiple Spanning Trees support in the bridge to allow
    reuse of topologies across VLANs, saving HW resources in switches.
 
  - DSA (Distributed Switch Architecture):
    - replay and offload of host VLAN entries
    - offload of static and local FDB entries on LAG interfaces
    - FDB isolation and unicast filtering
 
 New hardware / drivers
 ----------------------
 
  - Ethernet:
    - LAN937x T1 PHYs
    - Davicom DM9051 SPI NIC driver
    - Realtek RTL8367S, RTL8367RB-VB switch and MDIO
    - Microchip ksz8563 switches
    - Netronome NFP3800 SmartNICs
    - Fungible SmartNICs
    - MediaTek MT8195 switches
 
  - WiFi:
    - mt76: MediaTek mt7916
    - mt76: MediaTek mt7921u USB adapters
    - brcmfmac: Broadcom BCM43454/6
 
  - Mobile:
    - iosm: Intel M.2 7360 WWAN card
 
 Drivers
 -------
 
  - Convert many drivers to the new phylink API built for split PCS
    designs but also simplifying other cases.
 
  - Intel Ethernet NICs:
    - add TTY for GNSS module for E810T device
    - improve AF_XDP performance
    - GTP-C and GTP-U filter offload
    - QinQ VLAN support
 
  - Mellanox Ethernet NICs (mlx5):
    - support xdp->data_meta
    - multi-buffer XDP
    - offload tc push_eth and pop_eth actions
 
  - Netronome Ethernet NICs (nfp):
    - flow-independent tc action hardware offload (police / meter)
    - AF_XDP
 
  - Other Ethernet NICs:
    - at803x: fiber and SFP support
    - xgmac: mdio: preamble suppression and custom MDC frequencies
    - r8169: enable ASPM L1.2 if system vendor flags it as safe
    - macb/gem: ZynqMP SGMII
    - hns3: add TX push mode
    - dpaa2-eth: software TSO
    - lan743x: multi-queue, mdio, SGMII, PTP
    - axienet: NAPI and GRO support
 
  - Mellanox Ethernet switches (mlxsw):
    - source and dest IP address rewrites
    - RJ45 ports
 
  - Marvell Ethernet switches (prestera):
    - basic routing offload
    - multi-chain TC ACL offload
 
  - NXP embedded Ethernet switches (ocelot & felix):
    - PTP over UDP with the ocelot-8021q DSA tagging protocol
    - basic QoS classification on Felix DSA switch using dcbnl
    - port mirroring for ocelot switches
 
  - Microchip high-speed industrial Ethernet (sparx5):
    - offloading of bridge port flooding flags
    - PTP Hardware Clock
 
  - Other embedded switches:
    - lan966x: PTP Hardward Clock
    - qca8k: mdio read/write operations via crafted Ethernet packets
 
  - Qualcomm 802.11ax WiFi (ath11k):
    - add LDPC FEC type and 802.11ax High Efficiency data in radiotap
    - enable RX PPDU stats in monitor co-exist mode
 
  - Intel WiFi (iwlwifi):
    - UHB TAS enablement via BIOS
    - band disablement via BIOS
    - channel switch offload
    - 32 Rx AMPDU sessions in newer devices
 
  - MediaTek WiFi (mt76):
    - background radar detection
    - thermal management improvements on mt7915
    - SAR support for more mt76 platforms
    - MBSSID and 6 GHz band on mt7915
 
  - RealTek WiFi:
    - rtw89: AP mode
    - rtw89: 160 MHz channels and 6 GHz band
    - rtw89: hardware scan
 
  - Bluetooth:
    - mt7921s: wake on Bluetooth, SCO over I2S, wide-band-speed (WBS)
 
  - Microchip CAN (mcp251xfd):
    - multiple RX-FIFOs and runtime configurable RX/TX rings
    - internal PLL, runtime PM handling simplification
    - improve chip detection and error handling after wakeup
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "The sprinkling of SPI drivers is because we added a new one and Mark
  sent us a SPI driver interface conversion pull request.

  Core
  ----

   - Introduce XDP multi-buffer support, allowing the use of XDP with
     jumbo frame MTUs and combination with Rx coalescing offloads (LRO).

   - Speed up netns dismantling (5x) and lower the memory cost a little.
     Remove unnecessary per-netns sockets. Scope some lists to a netns.
     Cut down RCU syncing. Use batch methods. Allow netdev registration
     to complete out of order.

   - Support distinguishing timestamp types (ingress vs egress) and
     maintaining them across packet scrubbing points (e.g. redirect).

   - Continue the work of annotating packet drop reasons throughout the
     stack.

   - Switch netdev error counters from an atomic to dynamically
     allocated per-CPU counters.

   - Rework a few preempt_disable(), local_irq_save() and busy waiting
     sections problematic on PREEMPT_RT.

   - Extend the ref_tracker to allow catching use-after-free bugs.

  BPF
  ---

   - Introduce "packing allocator" for BPF JIT images. JITed code is
     marked read only, and used to be allocated at page granularity.
     Custom allocator allows for more efficient memory use, lower iTLB
     pressure and prevents identity mapping huge pages from getting
     split.

   - Make use of BTF type annotations (e.g. __user, __percpu) to enforce
     the correct probe read access method, add appropriate helpers.

   - Convert the BPF preload to use light skeleton and drop the
     user-mode-driver dependency.

   - Allow XDP BPF_PROG_RUN test infra to send real packets, enabling
     its use as a packet generator.

   - Allow local storage memory to be allocated with GFP_KERNEL if
     called from a hook allowed to sleep.

   - Introduce fprobe (multi kprobe) to speed up mass attachment (arch
     bits to come later).

   - Add unstable conntrack lookup helpers for BPF by using the BPF
     kfunc infra.

   - Allow cgroup BPF progs to return custom errors to user space.

   - Add support for AF_UNIX iterator batching.

   - Allow iterator programs to use sleepable helpers.

   - Support JIT of add, and, or, xor and xchg atomic ops on arm64.

   - Add BTFGen support to bpftool which allows to use CO-RE in kernels
     without BTF info.

   - Large number of libbpf API improvements, cleanups and deprecations.

  Protocols
  ---------

   - Micro-optimize UDPv6 Tx, gaining up to 5% in test on dummy netdev.

   - Adjust TSO packet sizes based on min_rtt, allowing very low latency
     links (data centers) to always send full-sized TSO super-frames.

   - Make IPv6 flow label changes (AKA hash rethink) more configurable,
     via sysctl and setsockopt. Distinguish between server and client
     behavior.

   - VxLAN support to "collect metadata" devices to terminate only
     configured VNIs. This is similar to VLAN filtering in the bridge.

   - Support inserting IPv6 IOAM information to a fraction of frames.

   - Add protocol attribute to IP addresses to allow identifying where
     given address comes from (kernel-generated, DHCP etc.)

   - Support setting socket and IPv6 options via cmsg on ping6 sockets.

   - Reject mis-use of ECN bits in IP headers as part of DSCP/TOS.
     Define dscp_t and stop taking ECN bits into account in fib-rules.

   - Add support for locked bridge ports (for 802.1X).

   - tun: support NAPI for packets received from batched XDP buffs,
     doubling the performance in some scenarios.

   - IPv6 extension header handling in Open vSwitch.

   - Support IPv6 control message load balancing in bonding, prevent
     neighbor solicitation and advertisement from using the wrong port.
     Support NS/NA monitor selection similar to existing ARP monitor.

   - SMC
      - improve performance with TCP_CORK and sendfile()
      - support auto-corking
      - support TCP_NODELAY

   - MCTP (Management Component Transport Protocol)
      - add user space tag control interface
      - I2C binding driver (as specified by DMTF DSP0237)

   - Multi-BSSID beacon handling in AP mode for WiFi.

   - Bluetooth:
      - handle MSFT Monitor Device Event
      - add MGMT Adv Monitor Device Found/Lost events

   - Multi-Path TCP:
      - add support for the SO_SNDTIMEO socket option
      - lots of selftest cleanups and improvements

   - Increase the max PDU size in CAN ISOTP to 64 kB.

  Driver API
  ----------

   - Add HW counters for SW netdevs, a mechanism for devices which
     offload packet forwarding to report packet statistics back to
     software interfaces such as tunnels.

   - Select the default NIC queue count as a fraction of number of
     physical CPU cores, instead of hard-coding to 8.

   - Expose devlink instance locks to drivers. Allow device layer of
     drivers to use that lock directly instead of creating their own
     which always runs into ordering issues in devlink callbacks.

   - Add header/data split indication to guide user space enabling of
     TCP zero-copy Rx.

   - Allow configuring completion queue event size.

   - Refactor page_pool to enable fragmenting after allocation.

   - Add allocation and page reuse statistics to page_pool.

   - Improve Multiple Spanning Trees support in the bridge to allow
     reuse of topologies across VLANs, saving HW resources in switches.

   - DSA (Distributed Switch Architecture):
      - replay and offload of host VLAN entries
      - offload of static and local FDB entries on LAG interfaces
      - FDB isolation and unicast filtering

  New hardware / drivers
  ----------------------

   - Ethernet:
      - LAN937x T1 PHYs
      - Davicom DM9051 SPI NIC driver
      - Realtek RTL8367S, RTL8367RB-VB switch and MDIO
      - Microchip ksz8563 switches
      - Netronome NFP3800 SmartNICs
      - Fungible SmartNICs
      - MediaTek MT8195 switches

   - WiFi:
      - mt76: MediaTek mt7916
      - mt76: MediaTek mt7921u USB adapters
      - brcmfmac: Broadcom BCM43454/6

   - Mobile:
      - iosm: Intel M.2 7360 WWAN card

  Drivers
  -------

   - Convert many drivers to the new phylink API built for split PCS
     designs but also simplifying other cases.

   - Intel Ethernet NICs:
      - add TTY for GNSS module for E810T device
      - improve AF_XDP performance
      - GTP-C and GTP-U filter offload
      - QinQ VLAN support

   - Mellanox Ethernet NICs (mlx5):
      - support xdp->data_meta
      - multi-buffer XDP
      - offload tc push_eth and pop_eth actions

   - Netronome Ethernet NICs (nfp):
      - flow-independent tc action hardware offload (police / meter)
      - AF_XDP

   - Other Ethernet NICs:
      - at803x: fiber and SFP support
      - xgmac: mdio: preamble suppression and custom MDC frequencies
      - r8169: enable ASPM L1.2 if system vendor flags it as safe
      - macb/gem: ZynqMP SGMII
      - hns3: add TX push mode
      - dpaa2-eth: software TSO
      - lan743x: multi-queue, mdio, SGMII, PTP
      - axienet: NAPI and GRO support

   - Mellanox Ethernet switches (mlxsw):
      - source and dest IP address rewrites
      - RJ45 ports

   - Marvell Ethernet switches (prestera):
      - basic routing offload
      - multi-chain TC ACL offload

   - NXP embedded Ethernet switches (ocelot & felix):
      - PTP over UDP with the ocelot-8021q DSA tagging protocol
      - basic QoS classification on Felix DSA switch using dcbnl
      - port mirroring for ocelot switches

   - Microchip high-speed industrial Ethernet (sparx5):
      - offloading of bridge port flooding flags
      - PTP Hardware Clock

   - Other embedded switches:
      - lan966x: PTP Hardward Clock
      - qca8k: mdio read/write operations via crafted Ethernet packets

   - Qualcomm 802.11ax WiFi (ath11k):
      - add LDPC FEC type and 802.11ax High Efficiency data in radiotap
      - enable RX PPDU stats in monitor co-exist mode

   - Intel WiFi (iwlwifi):
      - UHB TAS enablement via BIOS
      - band disablement via BIOS
      - channel switch offload
      - 32 Rx AMPDU sessions in newer devices

   - MediaTek WiFi (mt76):
      - background radar detection
      - thermal management improvements on mt7915
      - SAR support for more mt76 platforms
      - MBSSID and 6 GHz band on mt7915

   - RealTek WiFi:
      - rtw89: AP mode
      - rtw89: 160 MHz channels and 6 GHz band
      - rtw89: hardware scan

   - Bluetooth:
      - mt7921s: wake on Bluetooth, SCO over I2S, wide-band-speed (WBS)

   - Microchip CAN (mcp251xfd):
      - multiple RX-FIFOs and runtime configurable RX/TX rings
      - internal PLL, runtime PM handling simplification
      - improve chip detection and error handling after wakeup"

* tag 'net-next-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2521 commits)
  llc: fix netdevice reference leaks in llc_ui_bind()
  drivers: ethernet: cpsw: fix panic when interrupt coaleceing is set via ethtool
  ice: don't allow to run ice_send_event_to_aux() in atomic ctx
  ice: fix 'scheduling while atomic' on aux critical err interrupt
  net/sched: fix incorrect vlan_push_eth dest field
  net: bridge: mst: Restrict info size queries to bridge ports
  net: marvell: prestera: add missing destroy_workqueue() in prestera_module_init()
  drivers: net: xgene: Fix regression in CRC stripping
  net: geneve: add missing netlink policy and size for IFLA_GENEVE_INNER_PROTO_INHERIT
  net: dsa: fix missing host-filtered multicast addresses
  net/mlx5e: Fix build warning, detected write beyond size of field
  iwlwifi: mvm: Don't fail if PPAG isn't supported
  selftests/bpf: Fix kprobe_multi test.
  Revert "rethook: x86: Add rethook x86 implementation"
  Revert "arm64: rethook: Add arm64 rethook implementation"
  Revert "powerpc: Add rethook support"
  Revert "ARM: rethook: Add rethook arm implementation"
  netdevice: add missing dm_private kdoc
  net: bridge: mst: prevent NULL deref in br_mst_info_size()
  selftests: forwarding: Use same VRF for port and VLAN upper
  ...
2022-03-24 13:13:26 -07:00
Linus Torvalds
3ce62cf4dc flexible-array transformations for 5.18-rc1
Hi Linus,
 
 Please, pull the following treewide patch that replaces zero-length arrays with
 flexible-array members. This patch has been baking in linux-next for a
 whole development cycle.
 
 Thanks
 --
 Gustavo
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Merge tag 'flexible-array-transformations-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull flexible-array transformations from Gustavo Silva:
 "Treewide patch that replaces zero-length arrays with flexible-array
  members.

  This has been baking in linux-next for a whole development cycle"

* tag 'flexible-array-transformations-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  treewide: Replace zero-length arrays with flexible-array members
2022-03-24 11:39:32 -07:00
Hengqi Chen
d0f325c34c libbpf: Close fd in bpf_object__reuse_map
pin_fd is dup-ed and assigned in bpf_map__reuse_fd. Close it
in bpf_object__reuse_map after reuse.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220319030533.3132250-1-hengqi.chen@gmail.com
2022-03-21 15:36:52 +01:00
Andrii Nakryiko
a8fee96202 libbpf: Avoid NULL deref when initializing map BTF info
If BPF object doesn't have an BTF info, don't attempt to search for BTF
types describing BPF map key or value layout.

Fixes: 262cfb74ff ("libbpf: Init btf_{key,value}_type_id on internal map open")
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/20220320001911.3640917-1-andrii@kernel.org
2022-03-20 18:53:04 -07:00
Delyan Kratunov
430025e5dc libbpf: Add subskeleton scaffolding
In symmetry with bpf_object__open_skeleton(),
bpf_object__open_subskeleton() performs the actual walking and linking
of maps, progs, and globals described by bpf_*_skeleton objects.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/6942a46fbe20e7ebf970affcca307ba616985b15.1647473511.git.delyank@fb.com
2022-03-17 23:11:16 -07:00
Delyan Kratunov
262cfb74ff libbpf: Init btf_{key,value}_type_id on internal map open
For internal and user maps, look up the key and value btf
types on open() and not load(), so that `bpf_map_btf_value_type_id`
is usable in `bpftool gen`.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/78dbe4e457b4a05e098fc6c8f50014b680c86e4e.1647473511.git.delyank@fb.com
2022-03-17 23:11:15 -07:00
Delyan Kratunov
bc380eb9d0 libbpf: .text routines are subprograms in strict mode
Currently, libbpf considers a single routine in .text to be a program. This
is particularly confusing when it comes to library objects - a single routine
meant to be used as an extern will instead be considered a bpf_program.

This patch hides this compatibility behavior behind the pre-existing
SEC_NAME strict mode flag.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/018de8d0d67c04bf436055270d35d394ba393505.1647473511.git.delyank@fb.com
2022-03-17 23:11:15 -07:00
Jiri Olsa
ddc6b04989 libbpf: Add bpf_program__attach_kprobe_multi_opts function
Adding bpf_program__attach_kprobe_multi_opts function for attaching
kprobe program to multiple functions.

  struct bpf_link *
  bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog,
                                        const char *pattern,
                                        const struct bpf_kprobe_multi_opts *opts);

User can specify functions to attach with 'pattern' argument that
allows wildcards (*?' supported) or provide symbols or addresses
directly through opts argument. These 3 options are mutually
exclusive.

When using symbols or addresses, user can also provide cookie value
for each symbol/address that can be retrieved later in bpf program
with bpf_get_attach_cookie helper.

  struct bpf_kprobe_multi_opts {
          size_t sz;
          const char **syms;
          const unsigned long *addrs;
          const __u64 *cookies;
          size_t cnt;
          bool retprobe;
          size_t :0;
  };

Symbols, addresses and cookies are provided through opts object
(syms/addrs/cookies) as array pointers with specified count (cnt).

Each cookie value is paired with provided function address or symbol
with the same array index.

The program can be also attached as return probe if 'retprobe' is set.

For quick usage with NULL opts argument, like:

  bpf_program__attach_kprobe_multi_opts(prog, "ksys_*", NULL)

the 'prog' will be attached as kprobe to 'ksys_*' functions.

Also adding new program sections for automatic attachment:

  kprobe.multi/<symbol_pattern>
  kretprobe.multi/<symbol_pattern>

The symbol_pattern is used as 'pattern' argument in
bpf_program__attach_kprobe_multi_opts function.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-10-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Jiri Olsa
5117c26e87 libbpf: Add bpf_link_create support for multi kprobes
Adding new kprobe_multi struct to bpf_link_create_opts object
to pass multiple kprobe data to link_create attr uapi.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-9-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Jiri Olsa
85153ac062 libbpf: Add libbpf_kallsyms_parse function
Move the kallsyms parsing in internal libbpf_kallsyms_parse
function, so it can be used from other places.

It will be used in following changes.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220316122419.933957-8-jolsa@kernel.org
2022-03-17 20:17:19 -07:00
Toke Høiland-Jørgensen
24592ad1ab libbpf: Support batch_size option to bpf_prog_test_run
Add support for setting the new batch_size parameter to BPF_PROG_TEST_RUN
to libbpf; just add it as an option and pass it through to the kernel.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220309105346.100053-4-toke@redhat.com
2022-03-09 14:19:22 -08:00
Guo Zhengkui
04b6de649e libbpf: Fix array_size.cocci warning
Fix the following coccicheck warning:
tools/lib/bpf/bpf.c:114:31-32: WARNING: Use ARRAY_SIZE
tools/lib/bpf/xsk.c:484:34-35: WARNING: Use ARRAY_SIZE
tools/lib/bpf/xsk.c:485:35-36: WARNING: Use ARRAY_SIZE

It has been tested with gcc (Debian 8.3.0-6) 8.3.0 on x86_64.

Signed-off-by: Guo Zhengkui <guozhengkui@vivo.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220306023426.19324-1-guozhengkui@vivo.com
2022-03-07 22:13:00 -08:00
lic121
9c6e6a80ee libbpf: Unmap rings when umem deleted
xsk_umem__create() does mmap for fill/comp rings, but xsk_umem__delete()
doesn't do the unmap. This works fine for regular cases, because
xsk_socket__delete() does unmap for the rings. But for the case that
xsk_socket__create_shared() fails, umem rings are not unmapped.

fill_save/comp_save are checked to determine if rings have already be
unmapped by xsk. If fill_save and comp_save are NULL, it means that the
rings have already been used by xsk. Then they are supposed to be
unmapped by xsk_socket__delete(). Otherwise, xsk_umem__delete() does the
unmap.

Fixes: 2f6324a393 ("libbpf: Support shared umems between queues and devices")
Signed-off-by: Cheng Li <lic121@chinatelecom.cn>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220301132623.GA19995@vscode.7~
2022-03-07 21:56:54 -08:00
Andrii Nakryiko
697f104db8 libbpf: Support custom SEC() handlers
Allow registering and unregistering custom handlers for BPF program.
This allows user applications and libraries to plug into libbpf's
declarative SEC() definition handling logic. This allows to offload
complex and intricate custom logic into external libraries, but still
provide a great user experience.

One such example is USDT handling library, which has a lot of code and
complexity which doesn't make sense to put into libbpf directly, but it
would be really great for users to be able to specify BPF programs with
something like SEC("usdt/<path-to-binary>:<usdt_provider>:<usdt_name>")
and have correct BPF program type set (BPF_PROGRAM_TYPE_KPROBE, as it is
uprobe) and even support BPF skeleton's auto-attach logic.

In some cases, it might be even good idea to override libbpf's default
handling, like for SEC("perf_event") programs. With custom library, it's
possible to extend logic to support specifying perf event specification
right there in SEC() definition without burdening libbpf with lots of
custom logic or extra library dependecies (e.g., libpfm4). With current
patch it's possible to override libbpf's SEC("perf_event") handling and
specify a completely custom ones.

Further, it's possible to specify a generic fallback handling for any
SEC() that doesn't match any other custom or standard libbpf handlers.
This allows to accommodate whatever legacy use cases there might be, if
necessary.

See doc comments for libbpf_register_prog_handler() and
libbpf_unregister_prog_handler() for detailed semantics.

This patch also bumps libbpf development version to v0.8 and adds new
APIs there.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20220305010129.1549719-3-andrii@kernel.org
2022-03-05 09:38:15 -08:00
Andrii Nakryiko
4fa5bcfe07 libbpf: Allow BPF program auto-attach handlers to bail out
Allow some BPF program types to support auto-attach only in subste of
cases. Currently, if some BPF program type specifies attach callback, it
is assumed that during skeleton attach operation all such programs
either successfully attach or entire skeleton attachment fails. If some
program doesn't support auto-attachment from skeleton, such BPF program
types shouldn't have attach callback specified.

This is limiting for cases when, depending on how full the SEC("")
definition is, there could either be enough details to support
auto-attach or there might not be and user has to use some specific API
to provide more details at runtime.

One specific example of such desired behavior might be SEC("uprobe"). If
it's specified as just uprobe auto-attach isn't possible. But if it's
SEC("uprobe/<some_binary>:<some_func>") then there are enough details to
support auto-attach. Note that there is a somewhat subtle difference
between auto-attach behavior of BPF skeleton and using "generic"
bpf_program__attach(prog) (which uses the same attach handlers under the
cover). Skeleton allow some programs within bpf_object to not have
auto-attach implemented and doesn't treat that as an error. Instead such
BPF programs are just skipped during skeleton's (optional) attach step.
bpf_program__attach(), on the other hand, is called when user *expects*
auto-attach to work, so if specified program doesn't implement or
doesn't support auto-attach functionality, that will be treated as an
error.

Another improvement to the way libbpf is handling SEC()s would be to not
require providing dummy kernel function name for kprobe. Currently,
SEC("kprobe/whatever") is necessary even if actual kernel function is
determined by user at runtime and bpf_program__attach_kprobe() is used
to specify it. With changes in this patch, it's possible to support both
SEC("kprobe") and SEC("kprobe/<actual_kernel_function"), while only in
the latter case auto-attach will be performed. In the former one, such
kprobe will be skipped during skeleton attach operation.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20220305010129.1549719-2-andrii@kernel.org
2022-03-05 09:38:15 -08:00
Yuntao Wang
41332d6e3a libbpf: Add a check to ensure that page_cnt is non-zero
The page_cnt parameter is used to specify the number of memory pages
allocated for each per-CPU buffer, it must be non-zero and a power of 2.

Currently, the __perf_buffer__new() function attempts to validate that
the page_cnt is a power of 2 but forgets checking for the case where
page_cnt is zero, we can fix it by replacing 'page_cnt & (page_cnt - 1)'
with 'page_cnt == 0 || (page_cnt & (page_cnt - 1))'.

If so, we also don't need to add a check in perf_buffer__new_v0_6_0() to
make sure that page_cnt is non-zero and the check for zero in
perf_buffer__new_raw_v0_6_0() can also be removed.

The code will be cleaner and more readable.

Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220303005921.53436-1-ytcoode@gmail.com
2022-03-03 16:23:22 +01:00
Xu Kuohai
4226961b00 libbpf: Skip forward declaration when counting duplicated type names
Currently if a declaration appears in the BTF before the definition, the
definition is dumped as a conflicting name, e.g.:

    $ bpftool btf dump file vmlinux format raw | grep "'unix_sock'"
    [81287] FWD 'unix_sock' fwd_kind=struct
    [89336] STRUCT 'unix_sock' size=1024 vlen=14

    $ bpftool btf dump file vmlinux format c | grep "struct unix_sock"
    struct unix_sock;
    struct unix_sock___2 {	<--- conflict, the "___2" is unexpected
		    struct unix_sock___2 *unix_sk;

This causes a compilation error if the dump output is used as a header file.

Fix it by skipping declaration when counting duplicated type names.

Fixes: 351131b51c ("libbpf: add btf_dump API for BTF-to-C conversion")
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220301053250.1464204-2-xukuohai@huawei.com
2022-03-01 13:40:57 +01:00