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Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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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
Since b8c96a6b466c ("certs: simplify $(srctree)/ handling and remove
config_filename macro"), when CONFIG_MODULE_SIG_KEY is empty,
signing_key.x509 fails to build:
CERT certs/signing_key.x509
Usage: extract-cert <source> <dest>
make[1]: *** [certs/Makefile:78: certs/signing_key.x509] Error 2
make: *** [Makefile:1831: certs] Error 2
Pass "" to the first argument of extract-cert to fix the build error.
Link: https://lore.kernel.org/linux-kbuild/20220120094606.2skuyb26yjlnu66q@lion.mk-sys.cz/T/#u
Fixes: b8c96a6b466c ("certs: simplify $(srctree)/ handling and remove config_filename macro")
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Michal Kubecek <mkubecek@suse.cz>
elf_mcount_loc and mcount_sort_thread definitions are not
initialized immediately within the function, which can cause
the judgment logic to use uninitialized values when the
initialization logic of subsequent code fails.
Link: https://lkml.kernel.org/r/20211212113358.34208-2-yinan@linux.alibaba.com
Link: https://lkml.kernel.org/r/20220118065241.42364-1-yinan@linux.alibaba.com
Fixes: 72b3942a173c ("scripts: ftrace - move the sort-processing in ftrace_init")
Tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Yinan Liu <yinan@linux.alibaba.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Add a test for aliases with hyphens in the name to ensure that the
pmu-events tables are as expects. There should be no reason why these sort
of aliases would be treated differently, but no harm in checking.
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/1642432215-234089-3-git-send-email-john.garry@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Merge yet more updates from Andrew Morton:
"This is the post-linux-next queue. Material which was based on or
dependent upon material which was in -next.
69 patches.
Subsystems affected by this patch series: mm (migration and zsmalloc),
sysctl, proc, and lib"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (69 commits)
mm: hide the FRONTSWAP Kconfig symbol
frontswap: remove support for multiple ops
mm: mark swap_lock and swap_active_head static
frontswap: simplify frontswap_register_ops
frontswap: remove frontswap_test
mm: simplify try_to_unuse
frontswap: remove the frontswap exports
frontswap: simplify frontswap_init
frontswap: remove frontswap_curr_pages
frontswap: remove frontswap_shrink
frontswap: remove frontswap_tmem_exclusive_gets
frontswap: remove frontswap_writethrough
mm: remove cleancache
lib/stackdepot: always do filter_irq_stacks() in stack_depot_save()
lib/stackdepot: allow optional init and stack_table allocation by kvmalloc()
proc: remove PDE_DATA() completely
fs: proc: store PDE()->data into inode->i_private
zsmalloc: replace get_cpu_var with local_lock
zsmalloc: replace per zpage lock with pool->migrate_lock
locking/rwlocks: introduce write_lock_nested
...
bitmap_list_string() is very ineffective when printing bitmaps with long
ranges of set bits because it calls find_next_bit for each bit in the
bitmap. We can do better by detecting ranges of set bits.
In my environment, before/after is 943008/31008 ns.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
When CONFIG_MODULE_SIG_KEY is PKCS#11 URL (pkcs11:*), signing_key.x509
fails to build:
certs/Makefile:77: *** target pattern contains no '%'. Stop.
Due to the typo, $(X509_DEP) contains a colon.
Fix it.
Fixes: b8c96a6b466c ("certs: simplify $(srctree)/ handling and remove config_filename macro")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
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