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Inject events from a perf.data file recorded in a virtual machine into
a perf.data file recorded on the host at the same time.
Only side band events (e.g. mmap, comm, fork, exit etc) and build IDs are
injected. Additionally, the guest kcore_dir is copied as kcore_dir__
appended to the machine PID.
This is non-trivial because:
o It is not possible to process 2 sessions simultaneously so instead
events are first written to a temporary file.
o To avoid conflict, guest sample IDs are replaced with new unused sample
IDs.
o Guest event's CPU is changed to be the host CPU because it is more
useful for reporting and analysis.
o Sample ID is mapped to machine PID which is recorded with VCPU in the
id index. This is important to allow guest events to be related to the
guest machine and VCPU.
o Timestamps must be converted.
o Events are inserted to obey finished-round ordering.
The anticipated use-case is:
- start recording sideband events in a guest machine
- start recording an AUX area trace on the host which can trace also the
guest (e.g. Intel PT)
- run test case on the guest
- stop recording on the host
- stop recording on the guest
- copy the guest perf.data file to the host
- inject the guest perf.data file sideband events into the host perf.data
file using perf inject
- the resulting perf.data file can now be used
Subsequent patches provide Intel PT support for this.
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Add helper reallocarray_as_needed() to reallocate an array to a larger
size and initialize the extra entries to an arbitrary value.
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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When registering a guest machine using machine_pid from the id index,
check perf.data for a matching kcore_dir subdirectory and set the
kallsyms file name accordingly. If set, use it to find the machine's
kernel symbols and object code (from kcore).
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Copies of /proc/kallsyms, /proc/modules and an extract of /proc/kcore can
be stored in the perf.data output directory under the subdirectory named
kcore_dir. Guest machines will have their files also under subdirectories
beginning kcore_dir__ followed by the machine pid. Make has_kcore_dir()
return true also if there is a guest machine kcore_dir.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Copies of /proc/kallsyms, /proc/modules and an extract of /proc/kcore can
be stored in the perf.data output directory under the subdirectory named
kcore_dir. Guest machines will have their files also under subdirectories
beginning kcore_dir__ followed by the machine pid. Remove these also when
removing kcore_dir.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Add machine_pid and vcpu to the intel-pt-events.py script.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Add machine_pid and vcpu to python sample events and context switch events.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Add machine_pid and vcpu to struct perf_record_auxtrace_error. The existing
fmt member is used to identify the new format.
The new members make it possible to easily differentiate errors from guest
machines.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Add machine_pid and vcpu to struct perf_dlfilter_sample. The 'size' can be
used to determine if the values are present, however machine_pid is zero if
unused in any case. vcpu should be ignored if machine_pid is zero.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Add fields machine_pid and vcpu. These are displayed only if machine_pid is
non-zero.
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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If machine_pid is set, use it to find the guest machine.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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When parsing a sample with a sample ID, copy machine_pid and vcpu from
perf_sample_id to perf_sample.
Note, machine_pid will be zero when unused, so only a non-zero value
represents a guest machine. vcpu should be ignored if machine_pid is zero.
Note also, machine_pid is used with events that have come from injecting a
guest perf.data file, however guest events recorded on the host (i.e. using
perf kvm) have the (QEMU) hypervisor process pid to identify them - refer
machines__find_for_cpumode().
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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It is possible to know which guest machine was running at a point in time
based on the PID of the currently running host thread. That is, perf
identifies guest machines by the PID of the hypervisor.
To determine the guest CPU, put it on the hypervisor (QEMU) thread for
that VCPU.
This is done when processing the id_index which provides the necessary
information.
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Now that id_index has machine_pid, use it to create guest machines.
Create the guest machines with an idle thread because guest events
for "swapper" will be possible.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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When injecting events from a guest perf.data file, the events will have
separate sample ID numbers. These ID numbers can then be used to determine
which machine an event belongs to. To facilitate that, add machine_pid and
vcpu to id_index records. For backward compatibility, these are added at
the end of the record, and the length of the record is used to determine
if they are present or not.
Note, this is needed because the events from a guest perf.data file contain
the pid/tid of the process running at that time inside the VM not the
pid/tid of the (QEMU) hypervisor thread. So a way is needed to relate
guest events back to the guest machine and VCPU, and using sample ID
numbers for that is relatively simple and convenient.
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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realname() returns NULL if the file is not in the file system, but we can
still remove it from the build ID cache in that case, so continue and
attempt the purge with the name provided.
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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When the guestmount option is used, a guest machine's file system mount
point is recorded in machine->root_dir.
perf already iterates guest machines when adding files to the build ID
cache, but does not take machine->root_dir into account.
Use machine->root_dir to find files for guest build IDs, and add them to
the build ID cache using the "proper" name i.e. relative to the guest root
directory not the host root directory.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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When reviewing the results of perf inject, it is useful to be able to see
the events in the order they appear in the file.
So add --dump-unsorted-raw-trace option to do an unsorted dump.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Add perf_event__synthesize_id_sample() to enable the synthesis of
ID samples.
This is needed by perf inject. When injecting events from a guest perf.data
file, there is a possibility that the sample ID numbers conflict. In that
case, perf_event__synthesize_id_sample() can be used to re-write the ID
sample.
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Factor out evsel__id_hdr_size() so it can be reused.
This is needed by perf inject. When injecting events from a guest perf.data
file, there is a possibility that the sample ID numbers conflict. To
re-write an ID sample, the old one needs to be removed first, which means
determining how big it is with evsel__id_hdr_size() and then subtracting
that from the event size.
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Export perf_event__process_finished_round() so it can be used elsewhere.
This is needed in perf inject to obey finished-round ordering.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Allow callers to get the ordered_events last flush timestamp.
This is needed in perf inject to obey finished-round ordering when
injecting additional events (e.g. from a guest perf.data file) with
timestamps. Any additional events that have timestamps before the last
flush time must be injected before the corresponding FINISHED_ROUND event.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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Export dsos__for_each_with_build_id() so it can be used elsewhere.
Signed-off-by: Adrian Hunter <[email protected]>
Acked-by: Ian Rogers <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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When building selftests out of the kernel tree the gpio.h the include
path is incorrect and the build falls back to the system includes
which may be outdated.
Add the KHDR_INCLUDES to the CFLAGS to include the gpio.h from the
build tree.
Fixes: 4f4d0af7b2d9 ("selftests: gpio: restore CFLAGS options")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Kent Gibson <[email protected]>
Signed-off-by: Bartosz Golaszewski <[email protected]>
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Building perf for MIPS failed after 9f79b8b72339 ("uapi: simplify
__ARCH_FLOCK{,64}_PAD a little") with the following error:
CC
/home/fainelli/work/buildroot/output/bmips/build/linux-custom/tools/perf/trace/beauty/fcntl.o
In file included from
../../../../host/mipsel-buildroot-linux-gnu/sysroot/usr/include/asm/fcntl.h:77,
from ../include/uapi/linux/fcntl.h:5,
from trace/beauty/fcntl.c:10:
../include/uapi/asm-generic/fcntl.h:188:8: error: redefinition of
'struct flock'
struct flock {
^~~~~
In file included from ../include/uapi/linux/fcntl.h:5,
from trace/beauty/fcntl.c:10:
../../../../host/mipsel-buildroot-linux-gnu/sysroot/usr/include/asm/fcntl.h:63:8:
note: originally defined here
struct flock {
^~~~~
This is due to the local copy under
tools/include/uapi/asm-generic/fcntl.h including the toolchain's kernel
headers which already define 'struct flock' and define
HAVE_ARCH_STRUCT_FLOCK to future inclusions make a decision as to
whether re-defining 'struct flock' is appropriate or not.
Make sure what do not re-define 'struct flock'
when HAVE_ARCH_STRUCT_FLOCK is already defined.
Fixes: 9f79b8b72339 ("uapi: simplify __ARCH_FLOCK{,64}_PAD a little")
Signed-off-by: Florian Fainelli <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
[arnd: sync with include/uapi/asm-generic/fcntl.h as well]
Signed-off-by: Arnd Bergmann <[email protected]>
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Change verbose and movable node build options to run-time options.
Movable node usage:
$ ./main -m
Or:
$ ./main --movable-node
Verbose usage:
$ ./main -v
Or:
$ ./main --verbose
Signed-off-by: Rebecca Mckeever <[email protected]>
Reviewed-by: David Hildenbrand <[email protected]>
Signed-off-by: Mike Rapoport <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Synthesized MMAP events have zero ino_generation, so do not compare
them to DSOs with a real ino_generation otherwise we end up with a DSO
without a build id.
Fixes: 0e3149f86b99ddab ("perf dso: Move dso_id from 'struct map' to 'struct dso'")
Signed-off-by: Adrian Hunter <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: [email protected]
Cc: Namhyung Kim <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Added clarification to the comment from Ian + more detailed explanation from Adrian ]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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The snprintf() function returns the number of bytes it *would* have
copied if there were enough space. So it can return > the
sizeof(gen->attach_target).
Fixes: 67234743736a ("libbpf: Generate loader program out of BPF ELF file.")
Signed-off-by: Dan Carpenter <[email protected]>
Acked-by: Martin KaFai Lau <[email protected]>
Link: https://lore.kernel.org/r/YtZ+oAySqIhFl6/J@kili
Signed-off-by: Alexei Starovoitov <[email protected]>
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The snprintf() function returns the number of bytes which *would*
have been copied if there were space. In other words, it can be
> sizeof(pin_path).
Fixes: c0fa1b6c3efc ("bpf: btf: Add BTF tests")
Signed-off-by: Dan Carpenter <[email protected]>
Acked-by: Martin KaFai Lau <[email protected]>
Link: https://lore.kernel.org/r/YtZ+aD/tZMkgOUw+@kili
Signed-off-by: Alexei Starovoitov <[email protected]>
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Add test validating that libbpf adjusts (and reflects adjusted) ringbuf
size early, before bpf_object is loaded. Also make sure we can't
successfully resize ringbuf map after bpf_object is loaded.
Signed-off-by: Andrii Nakryiko <[email protected]>
Acked-by: Yonghong Song <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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Make libbpf adjust RINGBUF map size (rounding it up to closest power-of-2
of page_size) more eagerly: during open phase when initializing the map
and on explicit calls to bpf_map__set_max_entries().
Such approach allows user to check actual size of BPF ringbuf even
before it's created in the kernel, but also it prevents various edge
case scenarios where BPF ringbuf size can get out of sync with what it
would be in kernel. One of them (reported in [0]) is during an attempt
to pin/reuse BPF ringbuf.
Move adjust_ringbuf_sz() helper closer to its first actual use. The
implementation of the helper is unchanged.
Also make detection of whether bpf_object is already loaded more robust
by checking obj->loaded explicitly, given that map->fd can be < 0 even
if bpf_object is already loaded due to ability to disable map creation
with bpf_map__set_autocreate(map, false).
[0] Closes: https://github.com/libbpf/libbpf/pull/530
Fixes: 0087a681fa8c ("libbpf: Automatically fix up BPF_MAP_TYPE_RINGBUF size, if necessary")
Signed-off-by: Andrii Nakryiko <[email protected]>
Acked-by: Yonghong Song <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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Fix documentation for bpf_skb_pull_data() helper for
when len == 0.
Fixes: fa15601ab31e ("bpf: add documentation for eBPF helpers (33-41)")
Signed-off-by: Joanne Koong <[email protected]>
Acked-by: Quentin Monnet <[email protected]>
Acked-by: Martin KaFai Lau <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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Teach libbpf to fallback to tracefs mount point (/sys/kernel/tracing) if
debugfs (/sys/kernel/debug/tracing) isn't mounted.
Acked-by: Yonghong Song <[email protected]>
Suggested-by: Connor O'Brien <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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Add a simple big 16MB array and validate access to the very last byte of
it to make sure that kernel supports > KMALLOC_MAX_SIZE value_size for
BPF array maps (which are backing .bss in this case).
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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Convert few selftest that used plain SEC("kprobe") with arch-specific
syscall wrapper prefix to ksyscall/kretsyscall and corresponding
BPF_KSYSCALL macro. test_probe_user.c is especially benefiting from this
simplification.
Tested-by: Alan Maguire <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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Add SEC("ksyscall")/SEC("ksyscall/<syscall_name>") and corresponding
kretsyscall variants (for return kprobes) to allow users to kprobe
syscall functions in kernel. These special sections allow to ignore
complexities and differences between kernel versions and host
architectures when it comes to syscall wrapper and corresponding
__<arch>_sys_<syscall> vs __se_sys_<syscall> differences, depending on
whether host kernel has CONFIG_ARCH_HAS_SYSCALL_WRAPPER (though libbpf
itself doesn't rely on /proc/config.gz for detecting this, see
BPF_KSYSCALL patch for how it's done internally).
Combined with the use of BPF_KSYSCALL() macro, this allows to just
specify intended syscall name and expected input arguments and leave
dealing with all the variations to libbpf.
In addition to SEC("ksyscall+") and SEC("kretsyscall+") add
bpf_program__attach_ksyscall() API which allows to specify syscall name
at runtime and provide associated BPF cookie value.
At the moment SEC("ksyscall") and bpf_program__attach_ksyscall() do not
handle all the calling convention quirks for mmap(), clone() and compat
syscalls. It also only attaches to "native" syscall interfaces. If host
system supports compat syscalls or defines 32-bit syscalls in 64-bit
kernel, such syscall interfaces won't be attached to by libbpf.
These limitations may or may not change in the future. Therefore it is
recommended to use SEC("kprobe") for these syscalls or if working with
compat and 32-bit interfaces is required.
Tested-by: Alan Maguire <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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Improve BPF_KPROBE_SYSCALL (and rename it to shorter BPF_KSYSCALL to
match libbpf's SEC("ksyscall") section name, added in next patch) to use
__kconfig variable to determine how to properly fetch syscall arguments.
Instead of relying on hard-coded knowledge of whether kernel's
architecture uses syscall wrapper or not (which only reflects the latest
kernel versions, but is not necessarily true for older kernels and won't
necessarily hold for later kernel versions on some particular host
architecture), determine this at runtime by attempting to create
perf_event (with fallback to kprobe event creation through tracefs on
legacy kernels, just like kprobe attachment code is doing) for kernel
function that would correspond to bpf() syscall on a system that has
CONFIG_ARCH_HAS_SYSCALL_WRAPPER set (e.g., for x86-64 it would try
'__x64_sys_bpf').
If host kernel uses syscall wrapper, syscall kernel function's first
argument is a pointer to struct pt_regs that then contains syscall
arguments. In such case we need to use bpf_probe_read_kernel() to fetch
actual arguments (which we do through BPF_CORE_READ() macro) from inner
pt_regs.
But if the kernel doesn't use syscall wrapper approach, input
arguments can be read from struct pt_regs directly with no probe reading.
All this feature detection is done without requiring /proc/config.gz
existence and parsing, and BPF-side helper code uses newly added
LINUX_HAS_SYSCALL_WRAPPER virtual __kconfig extern to keep in sync with
user-side feature detection of libbpf.
BPF_KSYSCALL() macro can be used both with SEC("kprobe") programs that
define syscall function explicitly (e.g., SEC("kprobe/__x64_sys_bpf"))
and SEC("ksyscall") program added in the next patch (which are the same
kprobe program with added benefit of libbpf determining correct kernel
function name automatically).
Kretprobe and kretsyscall (added in next patch) programs don't need
BPF_KSYSCALL as they don't provide access to input arguments. Normal
BPF_KRETPROBE is completely sufficient and is recommended.
Tested-by: Alan Maguire <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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Exercise libbpf's logic for unknown __weak virtual __kconfig externs.
USDT selftests are already excercising non-weak known virtual extern
already (LINUX_HAS_BPF_COOKIE), so no need to add explicit tests for it.
Tested-by: Alan Maguire <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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Libbpf supports single virtual __kconfig extern currently: LINUX_KERNEL_VERSION.
LINUX_KERNEL_VERSION isn't coming from /proc/kconfig.gz and is intead
customly filled out by libbpf.
This patch generalizes this approach to support more such virtual
__kconfig externs. One such extern added in this patch is
LINUX_HAS_BPF_COOKIE which is used for BPF-side USDT supporting code in
usdt.bpf.h instead of using CO-RE-based enum detection approach for
detecting bpf_get_attach_cookie() BPF helper. This allows to remove
otherwise not needed CO-RE dependency and keeps user-space and BPF-side
parts of libbpf's USDT support strictly in sync in terms of their
feature detection.
We'll use similar approach for syscall wrapper detection for
BPF_KSYSCALL() BPF-side macro in follow up patch.
Generally, currently libbpf reserves CONFIG_ prefix for Kconfig values
and LINUX_ for virtual libbpf-backed externs. In the future we might
extend the set of prefixes that are supported. This can be done without
any breaking changes, as currently any __kconfig extern with
unrecognized name is rejected.
For LINUX_xxx externs we support the normal "weak rule": if libbpf
doesn't recognize given LINUX_xxx extern but such extern is marked as
__weak, it is not rejected and defaults to zero. This follows
CONFIG_xxx handling logic and will allow BPF applications to
opportunistically use newer libbpf virtual externs without breaking on
older libbpf versions unnecessarily.
Tested-by: Alan Maguire <[email protected]>
Reviewed-by: Alan Maguire <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>
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Silence this perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'
diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
Reported-by: Arnaldo Carvalho de Melo <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
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In rseq_test, there are two threads, which are vCPU thread and migration
worker separately. Unfortunately, the test has the wrong PID passed to
sched_setaffinity() in the migration worker. It forces migration on the
migration worker because zeroed PID represents the calling thread, which
is the migration worker itself. It means the vCPU thread is never enforced
to migration and it can migrate at any time, which eventually leads to
failure as the following logs show.
host# uname -r
5.19.0-rc6-gavin+
host# # cat /proc/cpuinfo | grep processor | tail -n 1
processor : 223
host# pwd
/home/gavin/sandbox/linux.main/tools/testing/selftests/kvm
host# for i in `seq 1 100`; do \
echo "--------> $i"; ./rseq_test; done
--------> 1
--------> 2
--------> 3
--------> 4
--------> 5
--------> 6
==== Test Assertion Failure ====
rseq_test.c:265: rseq_cpu == cpu
pid=3925 tid=3925 errno=4 - Interrupted system call
1 0x0000000000401963: main at rseq_test.c:265 (discriminator 2)
2 0x0000ffffb044affb: ?? ??:0
3 0x0000ffffb044b0c7: ?? ??:0
4 0x0000000000401a6f: _start at ??:?
rseq CPU = 4, sched CPU = 27
Fix the issue by passing correct parameter, TID of the vCPU thread, to
sched_setaffinity() in the migration worker.
Fixes: 61e52f1630f5 ("KVM: selftests: Add a test for KVM_RUN+rseq to detect task migration bugs")
Suggested-by: Sean Christopherson <[email protected]>
Signed-off-by: Gavin Shan <[email protected]>
Reviewed-by: Oliver Upton <[email protected]>
Message-Id: <[email protected]>
Reviewed-by: Andrew Jones <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
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We need the USB fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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This new option displays all of the information needed to do external
BuildID-based symbolization of kernel stack traces, such as those collected
by bpf_get_stackid().
For each kernel module plus the main kernel, it displays the BuildID,
the start and end virtual addresses of that module's text range (rounded
out to page boundaries), and the pathname of the module.
When run as a non-privileged user, the actual addresses of the modules'
text ranges are not available, so the tools displays "0, <text length>" for
kernel modules and "0, 0xffffffffffffffff" for the kernel itself.
Sample output:
root# perf buildid-list -m
cf6df852fd4da122d616153353cc8f560fd12fe0 ffffffffa5400000 ffffffffa6001e27 [kernel.kallsyms]
1aa7209aa2acb067d66ed6cf7676d65066384d61 ffffffffc0087000 ffffffffc008b000 /lib/modules/5.15.15-1rodete2-amd64/kernel/crypto/sha512_generic.ko
3857815b5bf0183697b68f8fe0ea06121644041e ffffffffc008c000 ffffffffc0098000 /lib/modules/5.15.15-1rodete2-amd64/kernel/arch/x86/crypto/sha512-ssse3.ko
4081fde0bca2bc097cb3e9d1efcb836047d485f1 ffffffffc0099000 ffffffffc009f000 /lib/modules/5.15.15-1rodete2-amd64/kernel/drivers/acpi/button.ko
1ef81ba4890552ea6b0314f9635fc43fc8cef568 ffffffffc00a4000 ffffffffc00aa000 /lib/modules/5.15.15-1rodete2-amd64/kernel/crypto/cryptd.ko
cc5c985506cb240d7d082b55ed260cbb851f983e ffffffffc00af000 ffffffffc00b6000 /lib/modules/5.15.15-1rodete2-amd64/kernel/drivers/i2c/busses/i2c-piix4.ko
[...]
Committer notes:
u64 formatter should be PRIx64 for printing as hex numbers, fix this:
28 5.28 debian:experimental-x-mips : FAIL gcc version 11.2.0 (Debian 11.2.0-18)
builtin-buildid-list.c: In function 'buildid__map_cb':
builtin-buildid-list.c:32:24: error: format '%lx' expects argument of type 'long unsigned int', but argument 3 has type 'u64' {aka 'long long unsigned int'} [-Werror=format=]
32 | printf("%s %16lx %16lx", bid_buf, map->start, map->end);
| ~~~~^ ~~~~~~~~~~
| | |
| long unsigned int u64 {aka long long unsigned int}
| %16llx
builtin-buildid-list.c:32:30: error: format '%lx' expects argument of type 'long unsigned int', but argument 4 has type 'u64' {aka 'long long unsigned int'} [-Werror=format=]
32 | printf("%s %16lx %16lx", bid_buf, map->start, map->end);
| ~~~~^ ~~~~~~~~
| | |
| long unsigned int u64 {aka long long unsigned int}
| %16llx
cc1: all warnings being treated as errors
Signed-off-by: Blake Jones <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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To update the perf/core codebase.
Fix conflict by moving arch__post_evsel_config(evsel, attr) to the end
of evsel__config(), after what was added in:
49c692b7dfc9b6c0 ("perf offcpu: Accept allowed sample types only")
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
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When RDRAND was introduced, there was much discussion on whether it
should be trusted and how the kernel should handle that. Initially, two
mechanisms cropped up, CONFIG_ARCH_RANDOM, a compile time switch, and
"nordrand", a boot-time switch.
Later the thinking evolved. With a properly designed RNG, using RDRAND
values alone won't harm anything, even if the outputs are malicious.
Rather, the issue is whether those values are being *trusted* to be good
or not. And so a new set of options were introduced as the real
ones that people use -- CONFIG_RANDOM_TRUST_CPU and "random.trust_cpu".
With these options, RDRAND is used, but it's not always credited. So in
the worst case, it does nothing, and in the best case, maybe it helps.
Along the way, CONFIG_ARCH_RANDOM's meaning got sort of pulled into the
center and became something certain platforms force-select.
The old options don't really help with much, and it's a bit odd to have
special handling for these instructions when the kernel can deal fine
with the existence or untrusted existence or broken existence or
non-existence of that CPU capability.
Simplify the situation by removing CONFIG_ARCH_RANDOM and using the
ordinary asm-generic fallback pattern instead, keeping the two options
that are actually used. For now it leaves "nordrand" for now, as the
removal of that will take a different route.
Acked-by: Michael Ellerman <[email protected]>
Acked-by: Catalin Marinas <[email protected]>
Acked-by: Borislav Petkov <[email protected]>
Acked-by: Heiko Carstens <[email protected]>
Acked-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Jason A. Donenfeld <[email protected]>
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Booting with vsyscall=xonly results in the following vsyscall VMA:
ffffffffff600000-ffffffffff601000 --xp ... [vsyscall]
Test does read from fixed vsyscall address to determine if kernel
supports vsyscall page but it doesn't work because, well, vsyscall
page is execute only.
Fix test by trying to execute from the first byte of the page which
contains gettimeofday() stub. This should work because vsyscall
entry points have stable addresses by design.
Alexey, avoiding parsing .config, /proc/config.gz and
/proc/cmdline at all costs.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Alexey Dobriyan <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
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The objective is to test device migration mechanism in pages marked as
COW, for private and coherent device type. In case of writing to COW
private page(s), a page fault will migrate pages back to system memory
first. Then, these pages will be duplicated. In case of COW device
coherent type, pages are duplicated directly from device memory.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Alex Sierra <[email protected]>
Acked-by: Felix Kuehling <[email protected]>
Cc: Alistair Popple <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Jerome Glisse <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Ralph Campbell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
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The intention is to test hmm device coherent type under different get user
pages paths. Also, test gup with FOLL_LONGTERM flag set in device
coherent pages. These pages should get migrated back to system memory.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Alex Sierra <[email protected]>
Reviewed-by: Alistair Popple <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Felix Kuehling <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Jerome Glisse <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Ralph Campbell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
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Add two more parameters to set spm_addr_dev0 & spm_addr_dev1 addresses.
These two parameters configure the start SP addresses for each device in
test_hmm driver. Consequently, this configures zone device type as
coherent.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Alex Sierra <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
Acked-by: Felix Kuehling <[email protected]>
Reviewed-by: Alistair Popple <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Jerome Glisse <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Ralph Campbell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
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Test cases such as migrate_fault and migrate_multiple, were modified to
explicit migrate from device to sys memory without the need of page
faults, when using device coherent type.
Snapshot test case updated to read memory device type first and based on
that, get the proper returned results migrate_ping_pong test case added to
test explicit migration from device to sys memory for both private and
coherent zone types.
Helpers to migrate from device to sys memory and vicerversa were also
added.
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Alex Sierra <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
Acked-by: Felix Kuehling <[email protected]>
Reviewed-by: Alistair Popple <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Jerome Glisse <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Ralph Campbell <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
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