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Linux kernel
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This started out with me noticing that "dom0_max_vcpus=<N>" with <N>
larger than the number of physical CPUs reported through ACPI tables
would not bring up the "excess" vCPU-s. Addressing this is the primary
purpose of the change; CPU maps handling is being tidied only as far as
is necessary for the change here (with the effect of also avoiding the
setting up of too much per-CPU infrastructure, i.e. for CPUs which can
never come online).
Noticing that xen_fill_possible_map() is called way too early, whereas
xen_filter_cpu_maps() is called too late (after per-CPU areas were
already set up), and further observing that each of the functions serves
only one of Dom0 or DomU, it looked like it was better to simplify this.
Use the .get_smp_config hook instead, uniformly for Dom0 and DomU.
xen_fill_possible_map() can be dropped altogether, while
xen_filter_cpu_maps() is re-purposed but not otherwise changed.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/2dbd5f0a-9859-ca2d-085e-a02f7166c610@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Add missing ioctl "magic numbers" for various Xen interfaces
(xenbus_dev.h, gntalloc.h, gntdev.h, and privcmd.h).
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lore.kernel.org/r/20220131161959.16509-1-rdunlap@infradead.org
Signed-off-by: Juergen Gross <jgross@suse.com>
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The current implementation of gntdev guarantees that the first call to
IOCTL_GNTDEV_MAP_GRANT_REF will set @index to 0. This is required to
use gntdev for Wayland, which is a future desire of Qubes OS.
Additionally, requesting zero grants results in an error, but this was
not documented either. Document both of these.
Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/f66c5a4e-2034-00b5-a635-6983bd999c07@gmail.com
Signed-off-by: Juergen Gross <jgross@suse.com>
It is better/preferred not to include file names in source files
because (a) they are not needed and (b) they can be incorrect,
so just delete this incorrect file name.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lore.kernel.org/r/20220130191705.24971-1-rdunlap@infradead.org
Signed-off-by: Juergen Gross <jgross@suse.com>
There's no point in disabling x2APIC mode when running as a Xen HVM
guest, just enable it when available.
Remove some unneeded wrapping around the detection functions, and
simply provide a xen_x2apic_available helper that's a wrapper around
x2apic_supported.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20220121090146.13697-1-roger.pau@citrix.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Pull more perf tools updates from Arnaldo Carvalho de Melo:
- Fix printing 'phys_addr' in 'perf script'.
- Fix failure to add events with 'perf probe' in ppc64 due to not
removing leading dot (ppc64 ABIv1).
- Fix cpu_map__item() python binding building.
- Support event alias in form foo-bar-baz, add pmu-events and
parse-event tests for it.
- No need to setup affinities when starting a workload or attaching to
a pid.
- Use path__join() to compose a path instead of ad-hoc snprintf()
equivalent.
- Override attr->sample_period for non-libpfm4 events.
- Use libperf cpumap APIs instead of accessing the internal state
directly.
- Sync x86 arch prctl headers and files changed by the new
set_mempolicy_home_node syscall with the kernel sources.
- Remove duplicate include in cpumap.h.
- Remove redundant err variable.
* tag 'perf-tools-for-v5.17-2022-01-22' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf tools: Remove redundant err variable
perf test: Add parse-events test for aliases with hyphens
perf test: Add pmu-events test for aliases with hyphens
perf parse-events: Support event alias in form foo-bar-baz
perf evsel: Override attr->sample_period for non-libpfm4 events
perf cpumap: Remove duplicate include in cpumap.h
perf cpumap: Migrate to libperf cpumap api
perf python: Fix cpu_map__item() building
perf script: Fix printing 'phys_addr' failure issue
tools headers UAPI: Sync files changed by new set_mempolicy_home_node syscall
tools headers UAPI: Sync x86 arch prctl headers with the kernel sources
perf machine: Use path__join() to compose a path instead of snprintf(dir, '/', filename)
perf evlist: No need to setup affinities when disabling events for pid targets
perf evlist: No need to setup affinities when enabling events for pid targets
perf stat: No need to setup affinities when starting a workload
perf affinity: Allow passing a NULL arg to affinity__cleanup()
perf probe: Fix ppc64 'perf probe add events failed' case
Pull ftrace fix from Steven Rostedt:
"Fix s390 breakage from sorting mcount tables.
The latest merge of the tracing tree sorts the mcount table at build
time. But s390 appears to do things differently (like always) and
replaces the sorted table back to the original unsorted one. As the
ftrace algorithm depends on it being sorted, bad things happen when it
is not, and s390 experienced those bad things.
Add a new config to tell the boot if the mcount table is sorted or
not, and allow s390 to opt out of it"
* tag 'trace-v5.17-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Fix assuming build time sort works for s390
Return value from perf_event__process_tracing_data() directly instead
of taking this in another redundant variable.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20220112080109.666800-1-chi.minghao@zte.com.cn
Signed-off-by: CGEL ZTE <cgel.zte@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull Kbuild fixes from Masahiro Yamada:
- Bring include/uapi/linux/nfc.h into the UAPI compile-test coverage
- Revert the workaround of CONFIG_CC_IMPLICIT_FALLTHROUGH
- Fix build errors in certs/Makefile
* tag 'kbuild-fixes-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
certs: Fix build error when CONFIG_MODULE_SIG_KEY is empty
certs: Fix build error when CONFIG_MODULE_SIG_KEY is PKCS#11 URI
Revert "Makefile: Do not quote value for CONFIG_CC_IMPLICIT_FALLTHROUGH"
usr/include/Makefile: add linux/nfc.h to the compile-test coverage
To speed up the boot process, as mcount_loc needs to be sorted for ftrace
to work properly, sorting it at build time is more efficient than boot up
and can save milliseconds of time. Unfortunately, this change broke s390
as it will modify the mcount_loc location after the sorting takes place
and will put back the unsorted locations. Since the sorting is skipped at
boot up if it is believed that it was sorted at run time, ftrace can crash
as its algorithms are dependent on the list being sorted.
Add a new config BUILDTIME_MCOUNT_SORT that is set when
BUILDTIME_TABLE_SORT but not if S390 is set. Use this config to determine
if sorting should take place at boot up.
Link: https://lore.kernel.org/all/yt9dee51ctfn.fsf@linux.ibm.com/
Fixes: 72b3942a173c ("scripts: ftrace - move the sort-processing in ftrace_init")
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Tested-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Add a test which allows us to test parsing an event alias with hyphens.
Since these events typically do not exist on most host systems, add the
alias to the fake pmu.
Function perf_pmu__test_parse_init() has terms added to match known test
aliases.
Signed-off-by: John Garry <john.garry@huawei.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qi Liu <liuqi115@huawei.com>
Cc: Shaokun Zhang <zhangshaokun@hisilicon.com>
Cc: linuxarm@huawei.com
Link: https://lore.kernel.org/r/1642432215-234089-4-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull bitmap updates from Yury Norov:
- introduce for_each_set_bitrange()
- use find_first_*_bit() instead of find_next_*_bit() where possible
- unify for_each_bit() macros
* tag 'bitmap-5.17-rc1' of git://github.com/norov/linux:
vsprintf: rework bitmap_list_string
lib: bitmap: add performance test for bitmap_print_to_pagebuf
bitmap: unify find_bit operations
mm/percpu: micro-optimize pcpu_is_populated()
Replace for_each_*_bit_from() with for_each_*_bit() where appropriate
find: micro-optimize for_each_{set,clear}_bit()
include/linux: move for_each_bit() macros from bitops.h to find.h
cpumask: replace cpumask_next_* with cpumask_first_* where appropriate
tools: sync tools/bitmap with mother linux
all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate
cpumask: use find_first_and_bit()
lib: add find_first_and_bit()
arch: remove GENERIC_FIND_FIRST_BIT entirely
include: move find.h from asm_generic to linux
bitops: move find_bit_*_le functions from le.h to find.h
bitops: protect find_first_{,zero}_bit properly
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