26 Sep, 2019
2 commits
-
When a process expects no accesses to a certain memory range for a long
time, it could hint kernel that the pages can be reclaimed instantly but
data should be preserved for future use. This could reduce workingset
eviction so it ends up increasing performance.This patch introduces the new MADV_PAGEOUT hint to madvise(2) syscall.
MADV_PAGEOUT can be used by a process to mark a memory range as not
expected to be used for a long time so that kernel reclaims *any LRU*
pages instantly. The hint can help kernel in deciding which pages to
evict proactively.A note: It doesn't apply SWAP_CLUSTER_MAX LRU page isolation limit
intentionally because it's automatically bounded by PMD size. If PMD
size(e.g., 256) makes some trouble, we could fix it later by limit it to
SWAP_CLUSTER_MAX[1].- man-page material
MADV_PAGEOUT (since Linux x.x)
Do not expect access in the near future so pages in the specified
regions could be reclaimed instantly regardless of memory pressure.
Thus, access in the range after successful operation could cause
major page fault but never lose the up-to-date contents unlike
MADV_DONTNEED. Pages belonging to a shared mapping are only processed
if a write access is allowed for the calling process.MADV_PAGEOUT cannot be applied to locked pages, Huge TLB pages, or
VM_PFNMAP pages.[1] https://lore.kernel.org/lkml/20190710194719.GS29695@dhcp22.suse.cz/
[minchan@kernel.org: clear PG_active on MADV_PAGEOUT]
Link: http://lkml.kernel.org/r/20190802200643.GA181880@google.com
[akpm@linux-foundation.org: resolve conflicts with hmm.git]
Link: http://lkml.kernel.org/r/20190726023435.214162-5-minchan@kernel.org
Signed-off-by: Minchan Kim
Reported-by: kbuild test robot
Acked-by: Michal Hocko
Cc: James E.J. Bottomley
Cc: Richard Henderson
Cc: Ralf Baechle
Cc: Chris Zankel
Cc: Daniel Colascione
Cc: Dave Hansen
Cc: Hillf Danton
Cc: Joel Fernandes (Google)
Cc: Johannes Weiner
Cc: Kirill A. Shutemov
Cc: Oleksandr Natalenko
Cc: Shakeel Butt
Cc: Sonny Rao
Cc: Suren Baghdasaryan
Cc: Tim Murray
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Patch series "Introduce MADV_COLD and MADV_PAGEOUT", v7.
- Background
The Android terminology used for forking a new process and starting an app
from scratch is a cold start, while resuming an existing app is a hot
start. While we continually try to improve the performance of cold
starts, hot starts will always be significantly less power hungry as well
as faster so we are trying to make hot start more likely than cold start.To increase hot start, Android userspace manages the order that apps
should be killed in a process called ActivityManagerService.
ActivityManagerService tracks every Android app or service that the user
could be interacting with at any time and translates that into a ranked
list for lmkd(low memory killer daemon). They are likely to be killed by
lmkd if the system has to reclaim memory. In that sense they are similar
to entries in any other cache. Those apps are kept alive for
opportunistic performance improvements but those performance improvements
will vary based on the memory requirements of individual workloads.- Problem
Naturally, cached apps were dominant consumers of memory on the system.
However, they were not significant consumers of swap even though they are
good candidate for swap. Under investigation, swapping out only begins
once the low zone watermark is hit and kswapd wakes up, but the overall
allocation rate in the system might trip lmkd thresholds and cause a
cached process to be killed(we measured performance swapping out vs.
zapping the memory by killing a process. Unsurprisingly, zapping is 10x
times faster even though we use zram which is much faster than real
storage) so kill from lmkd will often satisfy the high zone watermark,
resulting in very few pages actually being moved to swap.- Approach
The approach we chose was to use a new interface to allow userspace to
proactively reclaim entire processes by leveraging platform information.
This allowed us to bypass the inaccuracy of the kernel’s LRUs for pages
that are known to be cold from userspace and to avoid races with lmkd by
reclaiming apps as soon as they entered the cached state. Additionally,
it could provide many chances for platform to use much information to
optimize memory efficiency.To achieve the goal, the patchset introduce two new options for madvise.
One is MADV_COLD which will deactivate activated pages and the other is
MADV_PAGEOUT which will reclaim private pages instantly. These new
options complement MADV_DONTNEED and MADV_FREE by adding non-destructive
ways to gain some free memory space. MADV_PAGEOUT is similar to
MADV_DONTNEED in a way that it hints the kernel that memory region is not
currently needed and should be reclaimed immediately; MADV_COLD is similar
to MADV_FREE in a way that it hints the kernel that memory region is not
currently needed and should be reclaimed when memory pressure rises.This patch (of 5):
When a process expects no accesses to a certain memory range, it could
give a hint to kernel that the pages can be reclaimed when memory pressure
happens but data should be preserved for future use. This could reduce
workingset eviction so it ends up increasing performance.This patch introduces the new MADV_COLD hint to madvise(2) syscall.
MADV_COLD can be used by a process to mark a memory range as not expected
to be used in the near future. The hint can help kernel in deciding which
pages to evict early during memory pressure.It works for every LRU pages like MADV_[DONTNEED|FREE]. IOW, It moves
active file page -> inactive file LRU
active anon page -> inacdtive anon LRUUnlike MADV_FREE, it doesn't move active anonymous pages to inactive file
LRU's head because MADV_COLD is a little bit different symantic.
MADV_FREE means it's okay to discard when the memory pressure because the
content of the page is *garbage* so freeing such pages is almost zero
overhead since we don't need to swap out and access afterward causes just
minor fault. Thus, it would make sense to put those freeable pages in
inactive file LRU to compete other used-once pages. It makes sense for
implmentaion point of view, too because it's not swapbacked memory any
longer until it would be re-dirtied. Even, it could give a bonus to make
them be reclaimed on swapless system. However, MADV_COLD doesn't mean
garbage so reclaiming them requires swap-out/in in the end so it's bigger
cost. Since we have designed VM LRU aging based on cost-model, anonymous
cold pages would be better to position inactive anon's LRU list, not file
LRU. Furthermore, it would help to avoid unnecessary scanning if system
doesn't have a swap device. Let's start simpler way without adding
complexity at this moment. However, keep in mind, too that it's a caveat
that workloads with a lot of pages cache are likely to ignore MADV_COLD on
anonymous memory because we rarely age anonymous LRU lists.* man-page material
MADV_COLD (since Linux x.x)
Pages in the specified regions will be treated as less-recently-accessed
compared to pages in the system with similar access frequencies. In
contrast to MADV_FREE, the contents of the region are preserved regardless
of subsequent writes to pages.MADV_COLD cannot be applied to locked pages, Huge TLB pages, or VM_PFNMAP
pages.[akpm@linux-foundation.org: resolve conflicts with hmm.git]
Link: http://lkml.kernel.org/r/20190726023435.214162-2-minchan@kernel.org
Signed-off-by: Minchan Kim
Reported-by: kbuild test robot
Acked-by: Michal Hocko
Acked-by: Johannes Weiner
Cc: James E.J. Bottomley
Cc: Richard Henderson
Cc: Ralf Baechle
Cc: Chris Zankel
Cc: Johannes Weiner
Cc: Daniel Colascione
Cc: Dave Hansen
Cc: Hillf Danton
Cc: Joel Fernandes (Google)
Cc: Kirill A. Shutemov
Cc: Oleksandr Natalenko
Cc: Shakeel Butt
Cc: Sonny Rao
Cc: Suren Baghdasaryan
Cc: Tim Murray
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
25 Sep, 2019
2 commits
-
Both pgtable_cache_init() and pgd_cache_init() are used to initialize kmem
cache for page table allocations on several architectures that do not use
PAGE_SIZE tables for one or more levels of the page table hierarchy.Most architectures do not implement these functions and use __weak default
NOP implementation of pgd_cache_init(). Since there is no such default
for pgtable_cache_init(), its empty stub is duplicated among most
architectures.Rename the definitions of pgd_cache_init() to pgtable_cache_init() and
drop empty stubs of pgtable_cache_init().Link: http://lkml.kernel.org/r/1566457046-22637-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport
Acked-by: Will Deacon [arm64]
Acked-by: Thomas Gleixner [x86]
Cc: Catalin Marinas
Cc: Ingo Molnar
Cc: Borislav Petkov
Cc: Matthew Wilcox
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Patch series "mm: remove quicklist page table caches".
A while ago Nicholas proposed to remove quicklist page table caches [1].
I've rebased his patch on the curren upstream and switched ia64 and sh to
use generic versions of PTE allocation.[1] https://lore.kernel.org/linux-mm/20190711030339.20892-1-npiggin@gmail.com
This patch (of 3):
Remove page table allocator "quicklists". These have been around for a
long time, but have not got much traction in the last decade and are only
used on ia64 and sh architectures.The numbers in the initial commit look interesting but probably don't
apply anymore. If anybody wants to resurrect this it's in the git
history, but it's unhelpful to have this code and divergent allocator
behaviour for minor archs.Also it might be better to instead make more general improvements to page
allocator if this is still so slow.Link: http://lkml.kernel.org/r/1565250728-21721-2-git-send-email-rppt@linux.ibm.com
Signed-off-by: Nicholas Piggin
Signed-off-by: Mike Rapoport
Cc: Tony Luck
Cc: Yoshinori Sato
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
20 Sep, 2019
1 commit
-
Pull Kbuild updates from Masahiro Yamada:
- add modpost warn exported symbols marked as 'static' because 'static'
and EXPORT_SYMBOL is an odd combination- break the build early if gold linker is used
- optimize the Bison rule to produce .c and .h files by a single
pattern rule- handle PREEMPT_RT in the module vermagic and UTS_VERSION
- warn CONFIG options leaked to the user-space except existing ones
- make single targets work properly
- rebuild modules when module linker scripts are updated
- split the module final link stage into scripts/Makefile.modfinal
- fix the missed error code in merge_config.sh
- improve the error message displayed on the attempt of the O= build in
unclean source tree- remove 'clean-dirs' syntax
- disable -Wimplicit-fallthrough warning for Clang
- add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC
- remove ARCH_{CPP,A,C}FLAGS variables
- add $(BASH) to run bash scripts
- change *CFLAGS_.o to take the relative path to $(obj)
instead of the basename- stop suppressing Clang's -Wunused-function warnings when W=1
- fix linux/export.h to avoid genksyms calculating CRC of trimmed
exported symbols- misc cleanups
* tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (63 commits)
genksyms: convert to SPDX License Identifier for lex.l and parse.y
modpost: use __section in the output to *.mod.c
modpost: use MODULE_INFO() for __module_depends
export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols
export.h: remove defined(__KERNEL__), which is no longer needed
kbuild: allow Clang to find unused static inline functions for W=1 build
kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN
kbuild: refactor scripts/Makefile.extrawarn
merge_config.sh: ignore unwanted grep errors
kbuild: change *FLAGS_.o to take the path relative to $(obj)
modpost: add NOFAIL to strndup
modpost: add guid_t type definition
kbuild: add $(BASH) to run scripts with bash-extension
kbuild: remove ARCH_{CPP,A,C}FLAGS
kbuild,arc: add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC
kbuild: Do not enable -Wimplicit-fallthrough for clang for now
kbuild: clean up subdir-ymn calculation in Makefile.clean
kbuild: remove unneeded '+' marker from cmd_clean
kbuild: remove clean-dirs syntax
kbuild: check clean srctree even earlier
...
04 Sep, 2019
1 commit
-
While the default ->mmap and ->get_sgtable implementations work for the
majority of our dma_map_ops impementations they are inherently safe
for others that don't use the page allocator or CMA and/or use their
own way of remapping not covered by the common code. So remove the
defaults if these methods are not wired up, but instead wire up the
default implementations for all safe instances.Fixes: e1c7e324539a ("dma-mapping: always provide the dma_map_ops based implementation")
Signed-off-by: Christoph Hellwig
22 Aug, 2019
1 commit
-
Add CONFIG_ASM_MODVERSIONS. This allows to remove one if-conditional
nesting in scripts/Makefile.build.scripts/Makefile.build is run every time Kbuild descends into a
sub-directory. So, I want to avoid $(wildcard ...) evaluation
where possible although computing $(wildcard ...) is so cheap that
it may not make measurable performance difference.Signed-off-by: Masahiro Yamada
Acked-by: Geert Uytterhoeven
17 Jul, 2019
2 commits
-
Merge more updates from Andrew Morton:
"VM:
- z3fold fixes and enhancements by Henry Burns and Vitaly Wool- more accurate reclaimed slab caches calculations by Yafang Shao
- fix MAP_UNINITIALIZED UAPI symbol to not depend on config, by
Christoph Hellwig- !CONFIG_MMU fixes by Christoph Hellwig
- new novmcoredd parameter to omit device dumps from vmcore, by
Kairui Song- new test_meminit module for testing heap and pagealloc
initialization, by Alexander Potapenko- ioremap improvements for huge mappings, by Anshuman Khandual
- generalize kprobe page fault handling, by Anshuman Khandual
- device-dax hotplug fixes and improvements, by Pavel Tatashin
- enable synchronous DAX fault on powerpc, by Aneesh Kumar K.V
- add pte_devmap() support for arm64, by Robin Murphy
- unify locked_vm accounting with a helper, by Daniel Jordan
- several misc fixes
core/lib:
- new typeof_member() macro including some users, by Alexey Dobriyan- make BIT() and GENMASK() available in asm, by Masahiro Yamada
- changed LIST_POISON2 on x86_64 to 0xdead000000000122 for better
code generation, by Alexey Dobriyan- rbtree code size optimizations, by Michel Lespinasse
- convert struct pid count to refcount_t, by Joel Fernandes
get_maintainer.pl:
- add --no-moderated switch to skip moderated ML's, by Joe Perchesmisc:
- ptrace PTRACE_GET_SYSCALL_INFO interface- coda updates
- gdb scripts, various"
[ Using merge message suggestion from Vlastimil Babka, with some editing - Linus ]
* emailed patches from Andrew Morton : (100 commits)
fs/select.c: use struct_size() in kmalloc()
mm: add account_locked_vm utility function
arm64: mm: implement pte_devmap support
mm: introduce ARCH_HAS_PTE_DEVMAP
mm: clean up is_device_*_page() definitions
mm/mmap: move common defines to mman-common.h
mm: move MAP_SYNC to asm-generic/mman-common.h
device-dax: "Hotremove" persistent memory that is used like normal RAM
mm/hotplug: make remove_memory() interface usable
device-dax: fix memory and resource leak if hotplug fails
include/linux/lz4.h: fix spelling and copy-paste errors in documentation
ipc/mqueue.c: only perform resource calculation if user valid
include/asm-generic/bug.h: fix "cut here" for WARN_ON for __WARN_TAINT architectures
scripts/gdb: add helpers to find and list devices
scripts/gdb: add lx-genpd-summary command
drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl
kernel/pid.c: convert struct pid count to refcount_t
drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings
select: shift restore_saved_sigmask_unless() into poll_select_copy_remaining()
select: change do_poll() to return -ERESTARTNOHAND rather than -EINTR
... -
isa_page_to_bus() is deprecated and is no longer used anywhere. Remove
it entirely.Link: http://lkml.kernel.org/r/20190613161155.16946-1-steve@sk2.org
Signed-off-by: Stephen Kitt
Acked-by: Thomas Gleixner
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
15 Jul, 2019
1 commit
-
A while ago Arnd made it possible to give new system calls the same
syscall number on all architectures (except alpha). To not break this
nice new feature let's mark 435 for clone3 as reserved on all
architectures that do not yet implement it.
Even if an architecture does not plan to implement it this ensures that
new system calls coming after clone3 will have the same number on all
architectures.Signed-off-by: Christian Brauner
Cc: linux-arch@vger.kernel.org
Cc: linux-alpha@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Link: https://lore.kernel.org/r/20190714192205.27190-2-christian@brauner.io
Reviewed-by: Arnd Bergmann
Signed-off-by: Christian Brauner
13 Jul, 2019
2 commits
-
Pull Kconfig updates from Masahiro Yamada:
- always require argument for --defconfig and remove the hard-coded
arch/$(ARCH)/defconfig path- make arch/$(SRCARCH)/configs/defconfig the new default of defconfig
- some code cleanups
* tag 'kconfig-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: remove meaningless if-conditional in conf_read()
kconfig: Fix spelling of sym_is_changable
unicore32: rename unicore32_defconfig to defconfig
kconfig: make arch/*/configs/defconfig the default of KBUILD_DEFCONFIG
kconfig: add static qualifier to expand_string()
kconfig: require the argument of --defconfig
kconfig: remove always false ifeq ($(KBUILD_DEFCONFIG,) conditional -
alpha allocates PTE pages with __get_free_page() and uses
GFP_KERNEL | __GFP_ZERO for the allocations.Switch it to the generic version that does exactly the same thing for the
kernel page tables and adds __GFP_ACCOUNT for the user PTEs.The alpha pte_free() and pte_free_kernel() versions are identical to the
generic ones and can be simply dropped.Link: http://lkml.kernel.org/r/1557296232-15361-3-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport
Cc: Albert Ou
Cc: Anshuman Khandual
Cc: Anton Ivanov
Cc: Arnd Bergmann
Cc: Catalin Marinas
Cc: Geert Uytterhoeven
Cc: Greentime Hu
Cc: Guan Xuetao
Cc: Guo Ren
Cc: Guo Ren
Cc: Helge Deller
Cc: Ley Foon Tan
Cc: Matthew Wilcox
Cc: Matt Turner
Cc: Michael Ellerman
Cc: Michal Hocko
Cc: Palmer Dabbelt
Cc: Paul Burton
Cc: Ralf Baechle
Cc: Richard Kuo
Cc: Richard Weinberger
Cc: Russell King
Cc: Sam Creasey
Cc: Vincent Chen
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
12 Jul, 2019
1 commit
-
Pull networking updates from David Miller:
"Some highlights from this development cycle:1) Big refactoring of ipv6 route and neigh handling to support
nexthop objects configurable as units from userspace. From David
Ahern.2) Convert explored_states in BPF verifier into a hash table,
significantly decreased state held for programs with bpf2bpf
calls, from Alexei Starovoitov.3) Implement bpf_send_signal() helper, from Yonghong Song.
4) Various classifier enhancements to mvpp2 driver, from Maxime
Chevallier.5) Add aRFS support to hns3 driver, from Jian Shen.
6) Fix use after free in inet frags by allocating fqdirs dynamically
and reworking how rhashtable dismantle occurs, from Eric Dumazet.7) Add act_ctinfo packet classifier action, from Kevin
Darbyshire-Bryant.8) Add TFO key backup infrastructure, from Jason Baron.
9) Remove several old and unused ISDN drivers, from Arnd Bergmann.
10) Add devlink notifications for flash update status to mlxsw driver,
from Jiri Pirko.11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski.
12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes.
13) Various enhancements to ipv6 flow label handling, from Eric
Dumazet and Willem de Bruijn.14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van
der Merwe, and others.15) Various improvements to axienet driver including converting it to
phylink, from Robert Hancock.16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean.
17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana
Radulescu.18) Add devlink health reporting to mlx5, from Moshe Shemesh.
19) Convert stmmac over to phylink, from Jose Abreu.
20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from
Shalom Toledo.21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera.
22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel.
23) Track spill/fill of constants in BPF verifier, from Alexei
Starovoitov.24) Support bounded loops in BPF, from Alexei Starovoitov.
25) Various page_pool API fixes and improvements, from Jesper Dangaard
Brouer.26) Just like ipv4, support ref-countless ipv6 route handling. From
Wei Wang.27) Support VLAN offloading in aquantia driver, from Igor Russkikh.
28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy.
29) Add flower GRE encap/decap support to nfp driver, from Pieter
Jansen van Vuuren.30) Protect against stack overflow when using act_mirred, from John
Hurley.31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen.
32) Use page_pool API in netsec driver, Ilias Apalodimas.
33) Add Google gve network driver, from Catherine Sullivan.
34) More indirect call avoidance, from Paolo Abeni.
35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan.
36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek.
37) Add MPLS manipulation actions to TC, from John Hurley.
38) Add sending a packet to connection tracking from TC actions, and
then allow flower classifier matching on conntrack state. From
Paul Blakey.39) Netfilter hw offload support, from Pablo Neira Ayuso"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits)
net/mlx5e: Return in default case statement in tx_post_resync_params
mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync().
net: dsa: add support for BRIDGE_MROUTER attribute
pkt_sched: Include const.h
net: netsec: remove static declaration for netsec_set_tx_de()
net: netsec: remove superfluous if statement
netfilter: nf_tables: add hardware offload support
net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload
net: flow_offload: add flow_block_cb_is_busy() and use it
net: sched: remove tcf block API
drivers: net: use flow block API
net: sched: use flow block API
net: flow_offload: add flow_block_cb_{priv, incref, decref}()
net: flow_offload: add list handling functions
net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()
net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
net: flow_offload: add flow_block_cb_setup_simple()
net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC
net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC
...
11 Jul, 2019
1 commit
-
Pull pidfd updates from Christian Brauner:
"This adds two main features.- First, it adds polling support for pidfds. This allows process
managers to know when a (non-parent) process dies in a race-free
way.The notification mechanism used follows the same logic that is
currently used when the parent of a task is notified of a child's
death. With this patchset it is possible to put pidfds in an
{e}poll loop and get reliable notifications for process (i.e.
thread-group) exit.- The second feature compliments the first one by making it possible
to retrieve pollable pidfds for processes that were not created
using CLONE_PIDFD.A lot of processes get created with traditional PID-based calls
such as fork() or clone() (without CLONE_PIDFD). For these
processes a caller can currently not create a pollable pidfd. This
is a problem for Android's low memory killer (LMK) and service
managers such as systemd.Both patchsets are accompanied by selftests.
It's perhaps worth noting that the work done so far and the work done
in this branch for pidfd_open() and polling support do already see
some adoption:- Android is in the process of backporting this work to all their LTS
kernels [1]- Service managers make use of pidfd_send_signal but will need to
wait until we enable waiting on pidfds for full adoption.- And projects I maintain make use of both pidfd_send_signal and
CLONE_PIDFD [2] and will use polling support and pidfd_open() too"[1] https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.9+backport%22
https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.14+backport%22
https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.19+backport%22[2] https://github.com/lxc/lxc/blob/aab6e3eb73c343231cdde775db938994fc6f2803/src/lxc/start.c#L1753
* tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
tests: add pidfd_open() tests
arch: wire-up pidfd_open()
pid: add pidfd_open()
pidfd: add polling selftests
pidfd: add polling support
09 Jul, 2019
3 commits
-
…iederm/user-namespace
Pull force_sig() argument change from Eric Biederman:
"A source of error over the years has been that force_sig has taken a
task parameter when it is only safe to use force_sig with the current
task.The force_sig function is built for delivering synchronous signals
such as SIGSEGV where the userspace application caused a synchronous
fault (such as a page fault) and the kernel responded with a signal.Because the name force_sig does not make this clear, and because the
force_sig takes a task parameter the function force_sig has been
abused for sending other kinds of signals over the years. Slowly those
have been fixed when the oopses have been tracked down.This set of changes fixes the remaining abusers of force_sig and
carefully rips out the task parameter from force_sig and friends
making this kind of error almost impossible in the future"* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus
signal: Remove the signal number and task parameters from force_sig_info
signal: Factor force_sig_info_to_task out of force_sig_info
signal: Generate the siginfo in force_sig
signal: Move the computation of force into send_signal and correct it.
signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
signal: Remove the task parameter from force_sig_fault
signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
signal: Explicitly call force_sig_fault on current
signal/unicore32: Remove tsk parameter from __do_user_fault
signal/arm: Remove tsk parameter from __do_user_fault
signal/arm: Remove tsk parameter from ptrace_break
signal/nds32: Remove tsk parameter from send_sigtrap
signal/riscv: Remove tsk parameter from do_trap
signal/sh: Remove tsk parameter from force_sig_info_fault
signal/um: Remove task parameter from send_sigtrap
signal/x86: Remove task parameter from send_sigtrap
signal: Remove task parameter from force_sig_mceerr
signal: Remove task parameter from force_sig
signal: Remove task parameter from force_sigsegv
... -
Pull locking updates from Ingo Molnar:
"The main changes in this cycle are:- rwsem scalability improvements, phase #2, by Waiman Long, which are
rather impressive:"On a 2-socket 40-core 80-thread Skylake system with 40 reader
and writer locking threads, the min/mean/max locking operations
done in a 5-second testing window before the patchset were:40 readers, Iterations Min/Mean/Max = 1,807/1,808/1,810
40 writers, Iterations Min/Mean/Max = 1,807/50,344/151,255After the patchset, they became:
40 readers, Iterations Min/Mean/Max = 30,057/31,359/32,741
40 writers, Iterations Min/Mean/Max = 94,466/95,845/97,098"There's a lot of changes to the locking implementation that makes
it similar to qrwlock, including owner handoff for more fair
locking.Another microbenchmark shows how across the spectrum the
improvements are:"With a locking microbenchmark running on 5.1 based kernel, the
total locking rates (in kops/s) on a 2-socket Skylake system
with equal numbers of readers and writers (mixed) before and
after this patchset were:# of Threads Before Patch After Patch
------------ ------------ -----------
2 2,618 4,193
4 1,202 3,726
8 802 3,622
16 729 3,359
32 319 2,826
64 102 2,744"The changes are extensive and the patch-set has been through
several iterations addressing various locking workloads. There
might be more regressions, but unless they are pathological I
believe we want to use this new implementation as the baseline
going forward.- jump-label optimizations by Daniel Bristot de Oliveira: the primary
motivation was to remove IPI disturbance of isolated RT-workload
CPUs, which resulted in the implementation of batched jump-label
updates. Beyond the improvement of the real-time characteristics
kernel, in one test this patchset improved static key update
overhead from 57 msecs to just 1.4 msecs - which is a nice speedup
as well.- atomic64_t cross-arch type cleanups by Mark Rutland: over the last
~10 years of atomic64_t existence the various types used by the
APIs only had to be self-consistent within each architecture -
which means they became wildly inconsistent across architectures.
Mark puts and end to this by reworking all the atomic64
implementations to use 's64' as the base type for atomic64_t, and
to ensure that this type is consistently used for parameters and
return values in the API, avoiding further problems in this area.- A large set of small improvements to lockdep by Yuyang Du: type
cleanups, output cleanups, function return type and othr cleanups
all around the place.- A set of percpu ops cleanups and fixes by Peter Zijlstra.
- Misc other changes - please see the Git log for more details"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (82 commits)
locking/lockdep: increase size of counters for lockdep statistics
locking/atomics: Use sed(1) instead of non-standard head(1) option
locking/lockdep: Move mark_lock() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING
x86/jump_label: Make tp_vec_nr static
x86/percpu: Optimize raw_cpu_xchg()
x86/percpu, sched/fair: Avoid local_clock()
x86/percpu, x86/irq: Relax {set,get}_irq_regs()
x86/percpu: Relax smp_processor_id()
x86/percpu: Differentiate this_cpu_{}() and __this_cpu_{}()
locking/rwsem: Guard against making count negative
locking/rwsem: Adaptive disabling of reader optimistic spinning
locking/rwsem: Enable time-based spinning on reader-owned rwsem
locking/rwsem: Make rwsem->owner an atomic_long_t
locking/rwsem: Enable readers spinning on writer
locking/rwsem: Clarify usage of owner's nonspinaable bit
locking/rwsem: Wake up almost all readers in wait queue
locking/rwsem: More optimal RT task handling of null owner
locking/rwsem: Always release wait_lock before waking up tasks
locking/rwsem: Implement lock handoff to prevent lock starvation
locking/rwsem: Make rwsem_spin_on_owner() return owner state
... -
Pull SMP/hotplug updates from Thomas Gleixner:
"A small set of updates for SMP and CPU hotplug:- Abort disabling secondary CPUs in the freezer when a wakeup is
pending instead of evaluating it only after all CPUs have been
offlined.- Remove the shared annotation for the strict per CPU cfd_data in the
smp function call core code.- Remove the return values of smp_call_function() and on_each_cpu()
as they are unconditionally 0. Fixup the few callers which actually
bothered to check the return value"* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
smp: Remove smp_call_function() and on_each_cpu() return values
smp: Do not mark call_function_data as shared
cpu/hotplug: Abort disabling secondary CPUs if wakeup is pending
cpu/hotplug: Fix notify_cpu_starting() reference in bringup_wait_for_ap()
28 Jun, 2019
1 commit
-
This wires up the pidfd_open() syscall into all arches at once.
Signed-off-by: Christian Brauner
Reviewed-by: David Howells
Reviewed-by: Oleg Nesterov
Acked-by: Arnd Bergmann
Cc: "Eric W. Biederman"
Cc: Kees Cook
Cc: Joel Fernandes (Google)
Cc: Thomas Gleixner
Cc: Jann Horn
Cc: Andy Lutomirsky
Cc: Andrew Morton
Cc: Aleksa Sarai
Cc: Linus Torvalds
Cc: Al Viro
Cc: linux-api@vger.kernel.org
Cc: linux-alpha@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Cc: linux-arch@vger.kernel.org
Cc: x86@kernel.org
23 Jun, 2019
1 commit
-
The return value is fixed. Remove it and amend the callers.
[ tglx: Fixup arm/bL_switcher and powerpc/rtas ]
Signed-off-by: Nadav Amit
Signed-off-by: Thomas Gleixner
Cc: Peter Zijlstra
Cc: Andy Lutomirski
Cc: Borislav Petkov
Cc: Dave Hansen
Cc: Richard Henderson
Cc: Ivan Kokshaysky
Cc: Matt Turner
Cc: Tony Luck
Cc: Fenghua Yu
Cc: Andrew Morton
Link: https://lkml.kernel.org/r/20190613064813.8102-2-namit@vmware.com
20 Jun, 2019
1 commit
-
Alexei Starovoitov says:
====================
pull-request: bpf-next 2019-06-19The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) new SO_REUSEPORT_DETACH_BPF setsocktopt, from Martin.
2) BTF based map definition, from Andrii.
3) support bpf_map_lookup_elem for xskmap, from Jonathan.
4) bounded loops and scalar precision logic in the verifier, from Alexei.
====================Signed-off-by: David S. Miller
17 Jun, 2019
1 commit
-
Signed-off-by: Ingo Molnar
15 Jun, 2019
1 commit
-
There is SO_ATTACH_REUSEPORT_[CE]BPF but there is no DETACH.
This patch adds SO_DETACH_REUSEPORT_BPF sockopt. The same
sockopt can be used to undo both SO_ATTACH_REUSEPORT_[CE]BPF.reseport_detach_prog() is added and it is mostly a mirror
of the existing reuseport_attach_prog(). The differences are,
it does not call reuseport_alloc() and returns -ENOENT when
there is no old prog.Cc: Craig Gallek
Signed-off-by: Martin KaFai Lau
Reviewed-by: Stanislav Fomichev
Signed-off-by: Daniel Borkmann
09 Jun, 2019
1 commit
-
Until recently, if KBUILD_DEFCONFIG was not set by the arch Makefile,
the default path arch/*/defconfig was used.The last users of the default are gone by the following commits:
- Commit f3e20ad67b4c ("s390: move arch/s390/defconfig to
arch/s390/configs/defconfig")- Commit 986a13769c4b ("alpha: move arch/alpha/defconfig to
arch/alpha/configs/defconfig")Let's set arch/*/configs/defconfig as a new default. This saves
KBUILD_DEFCONFIG for some architectures.Signed-off-by: Masahiro Yamada
Acked-by: Catalin Marinas
05 Jun, 2019
2 commits
-
Based on 1 normalized pattern(s):
this file is released under the gplv2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 68 file(s).
Signed-off-by: Thomas Gleixner
Reviewed-by: Armijn Hemel
Reviewed-by: Allison Randal
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190114.292346262@linutronix.de
Signed-off-by: Greg Kroah-Hartman -
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 59 temple place suite 330 boston ma 02111
1307 usaextracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 136 file(s).
Signed-off-by: Thomas Gleixner
Reviewed-by: Alexios Zavras
Reviewed-by: Allison Randal
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de
Signed-off-by: Greg Kroah-Hartman
03 Jun, 2019
1 commit
-
As a step towards making the atomic64 API use consistent types treewide,
let's have the alpha atomic64 implementation use s64 as the underlying
type for atomic64_t, rather than long, matching the generated headers.As atomic64_read() depends on the generic defintion of atomic64_t, this
still returns long. This will be converted in a subsequent patch.Otherwise, there should be no functional change as a result of this
patch.Signed-off-by: Mark Rutland
Signed-off-by: Peter Zijlstra (Intel)
Cc: Ivan Kokshaysky
Cc: Linus Torvalds
Cc: Matt Turner
Cc: Peter Zijlstra
Cc: Richard Henderson
Cc: Thomas Gleixner
Cc: Will Deacon
Cc: aou@eecs.berkeley.edu
Cc: arnd@arndb.de
Cc: bp@alien8.de
Cc: catalin.marinas@arm.com
Cc: davem@davemloft.net
Cc: fenghua.yu@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: jhogan@kernel.org
Cc: linux@armlinux.org.uk
Cc: mpe@ellerman.id.au
Cc: palmer@sifive.com
Cc: paul.burton@mips.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: tony.luck@intel.com
Cc: vgupta@synopsys.com
Link: https://lkml.kernel.org/r/20190522132250.26499-5-mark.rutland@arm.com
Signed-off-by: Ingo Molnar
31 May, 2019
3 commits
-
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:GPL-2.0
Reported-by: Masahiro Yamada
Signed-off-by: Greg Kroah-Hartman
Reviewed-by: Kate Stewart
Signed-off-by: Greg Kroah-Hartman -
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usaextracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1334 file(s).
Signed-off-by: Thomas Gleixner
Reviewed-by: Allison Randal
Reviewed-by: Richard Fontana
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman -
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later versionextracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: Thomas Gleixner
Reviewed-by: Allison Randal
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman
29 May, 2019
1 commit
-
As synchronous exceptions really only make sense against the current
task (otherwise how are you synchronous) remove the task parameter
from from force_sig_fault to make it explicit that is what is going
on.The two known exceptions that deliver a synchronous exception to a
stopped ptraced task have already been changed to
force_sig_fault_to_task.The callers have been changed with the following emacs regular expression
(with obvious variations on the architectures that take more arguments)
to avoid typos:force_sig_fault[(]\([^,]+\)[,]\([^,]+\)[,]\([^,]+\)[,]\W+current[)]
->
force_sig_fault(\1,\2,\3)Signed-off-by: "Eric W. Biederman"
27 May, 2019
1 commit
-
All of the remaining callers pass current into force_sig so
remove the task parameter to make this obvious and to make
misuse more difficult in the future.This also makes it clear force_sig passes current into force_sig_info.
Signed-off-by: "Eric W. Biederman"
24 May, 2019
1 commit
-
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 or at your option any
later version you should have received a copy of the gnu general
public license for example usr src linux copying if not write to the
free software foundation inc 675 mass ave cambridge ma 02139 usaextracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 20 file(s).
Signed-off-by: Thomas Gleixner
Reviewed-by: Allison Randal
Reviewed-by: Kate Stewart
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170858.552543146@linutronix.de
Signed-off-by: Greg Kroah-Hartman
21 May, 2019
2 commits
-
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:GPL-2.0-only
Signed-off-by: Thomas Gleixner
Signed-off-by: Greg Kroah-Hartman -
Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have MODULE_LICENCE("GPL*") inside which was used in the initial
scan/conversion to ignore the fileThese files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:GPL-2.0-only
Signed-off-by: Thomas Gleixner
Signed-off-by: Greg Kroah-Hartman
18 May, 2019
2 commits
-
As of Linux 5.1, alpha and s390 are the last architectures that
have defconfig in arch/*/ instead of arch/*/configs/.$ find arch -name defconfig | sort
arch/alpha/defconfig
arch/arm64/configs/defconfig
arch/csky/configs/defconfig
arch/nds32/configs/defconfig
arch/riscv/configs/defconfig
arch/s390/defconfigThe arch/$(ARCH)/defconfig is the hard-coded default in Kconfig,
and I want to deprecate it after evacuating the remaining defconfig
into the standard location, arch/*/configs/.Define KBUILD_DEFCONFIG like other architectures, and move defconfig
into the configs/ subdirectory.Signed-off-by: Masahiro Yamada
Reviewed-by: Paul Walmsley -
Pull more vfs mount updates from Al Viro:
"Propagation of new syscalls to other architectures + cosmetic change
from Christian (fscontext didn't follow the convention for anon inode
names)"* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
uapi: Wire up the mount API syscalls on non-x86 arches [ver #2]
uapi, x86: Fix the syscall numbering of the mount API syscalls [ver #2]
uapi, fsopen: use square brackets around "fscontext" [ver #2]
17 May, 2019
2 commits
-
Pull nommu generic uaccess updates from Arnd Bergmann:
"asm-generic: kill and improve nommu generic uaccess helpersChristoph Hellwig writes:
This is a series doing two somewhat interwinded things. It improves
the asm-generic nommu uaccess helper to optionally be entirely
generic and not require any arch helpers for the actual uaccess.
For the generic uaccess.h to actually be generically useful I also
had to kill off the mess we made of , which really
shouldn't exist on most architectures"* tag 'asm-generic-nommu' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
asm-generic: optimize generic uaccess for 8-byte loads and stores
asm-generic: provide entirely generic nommu uaccess
arch: mostly remove
asm-generic: don't include from -
Wire up the mount API syscalls on non-x86 arches.
Reported-by: Arnd Bergmann
Signed-off-by: David Howells
Reviewed-by: Arnd Bergmann
Signed-off-by: Al Viro
15 May, 2019
2 commits
-
Patch series "provide a generic free_initmem implementation", v2.
Many architectures implement free_initmem() in exactly the same or very
similar way: they wrap the call to free_initmem_default() with sometimes
different 'poison' parameter.These patches switch those architectures to use a generic implementation
that does free_initmem_default(POISON_FREE_INITMEM).This was inspired by Christoph's patches for free_initrd_mem [1] and I
shamelessly copied changelog entries from his patches :)[1] https://lore.kernel.org/lkml/20190213174621.29297-1-hch@lst.de/
This patch (of 2):
For most architectures free_initmem just a wrapper for the same
free_initmem_default(-1) call. Provide that as a generic implementation
marked __weak.Link: http://lkml.kernel.org/r/1550515285-17446-2-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport
Reviewed-by: Andrew Morton
Cc: Christoph Hellwig
Cc: Palmer Dabbelt
Cc: Richard Kuo
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
For most architectures free_initrd_mem just expands to the same
free_reserved_area call. Provide that as a generic implementation marked
__weak.Link: http://lkml.kernel.org/r/20190213174621.29297-8-hch@lst.de
Signed-off-by: Christoph Hellwig
Acked-by: Geert Uytterhoeven [m68k]
Acked-by: Mike Rapoport
Cc: Catalin Marinas [arm64]
Cc: Steven Price
Cc: Alexander Viro
Cc: Guan Xuetao
Cc: Russell King
Cc: Will Deacon
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds