28 Jun, 2016
1 commit
-
This reverts commit 852ffd0f4e23248b47531058e531066a988434b5.
There are use cases where an intermediate boot kernel (1) uses kexec
to boot the final production kernel (2). For this scenario we should
provide the original boot information to the production kernel (2).
Therefore clearing the boot information during kexec() should not
be done.Cc: stable@vger.kernel.org # v3.17+
Reported-by: Steffen Maier
Signed-off-by: Michael Holzheu
Reviewed-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky
16 Jun, 2016
1 commit
-
On s390, there are two different hardware PMUs for counting and
sampling. Previously, both PMUs have shared the perf_hw_context
which is not correct and, recently, results in this warning:------------[ cut here ]------------
WARNING: CPU: 5 PID: 1 at kernel/events/core.c:8485 perf_pmu_register+0x420/0x428
Modules linked in:
CPU: 5 PID: 1 Comm: swapper/0 Not tainted 4.7.0-rc1+ #2
task: 00000009c5240000 ti: 00000009c5234000 task.ti: 00000009c5234000
Krnl PSW : 0704c00180000000 0000000000220c50 (perf_pmu_register+0x420/0x428)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3
Krnl GPRS: ffffffffffffffff 0000000000b15ac6 0000000000000000 00000009cb440000
000000000022087a 0000000000000000 0000000000b78fa0 0000000000000000
0000000000a9aa90 0000000000000084 0000000000000005 000000000088a97a
0000000000000004 0000000000749dd0 000000000022087a 00000009c5237cc0
Krnl Code: 0000000000220c44: a7f4ff54 brc 15,220aec
0000000000220c48: 92011000 mvi 0(%r1),1
#0000000000220c4c: a7f40001 brc 15,220c4e
>0000000000220c50: a7f4ff12 brc 15,220a74
0000000000220c54: 0707 bcr 0,%r7
0000000000220c56: 0707 bcr 0,%r7
0000000000220c58: ebdff0800024 stmg %r13,%r15,128(%r15)
0000000000220c5e: a7f13fe0 tmll %r15,16352
Call Trace:
([] perf_pmu_register+0x4a/0x428)
([] init_cpum_sampling_pmu+0x14c/0x1f8)
([] do_one_initcall+0x48/0x140)
([] kernel_init_freeable+0x1e6/0x2a0)
([] kernel_init+0x24/0x138)
([] kernel_thread_starter+0x6/0xc)
([] kernel_thread_starter+0x0/0xc)
Last Breaking-Event-Address:
[] perf_pmu_register+0x41c/0x428
---[ end trace 0c6ef9f5b771ad97 ]---Using the perf_sw_context is an option because the cpum_cf PMU does
not use interrupts. To make this more clear, initialize the
capabilities in the PMU structure.Signed-off-by: Hendrik Brueckner
Suggested-by: Peter Zijlstra
Acked-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky
26 May, 2016
1 commit
-
Pull perf updates from Ingo Molnar:
"Mostly tooling and PMU driver fixes, but also a number of late updates
such as the reworking of the call-chain size limiting logic to make
call-graph recording more robust, plus tooling side changes for the
new 'backwards ring-buffer' extension to the perf ring-buffer"* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
perf record: Read from backward ring buffer
perf record: Rename variable to make code clear
perf record: Prevent reading invalid data in record__mmap_read
perf evlist: Add API to pause/resume
perf trace: Use the ptr->name beautifier as default for "filename" args
perf trace: Use the fd->name beautifier as default for "fd" args
perf report: Add srcline_from/to branch sort keys
perf evsel: Record fd into perf_mmap
perf evsel: Add overwrite attribute and check write_backward
perf tools: Set buildid dir under symfs when --symfs is provided
perf trace: Only auto set call-graph to "dwarf" when syscalls are being traced
perf annotate: Sort list of recognised instructions
perf annotate: Fix identification of ARM blt and bls instructions
perf tools: Fix usage of max_stack sysctl
perf callchain: Stop validating callchains by the max_stack sysctl
perf trace: Fix exit_group() formatting
perf top: Use machine->kptr_restrict_warned
perf trace: Warn when trying to resolve kernel addresses with kptr_restrict=1
perf machine: Do not bail out if not managing to read ref reloc symbol
perf/x86/intel/p4: Trival indentation fix, remove space
...
24 May, 2016
2 commits
-
most architectures are relying on mmap_sem for write in their
arch_setup_additional_pages. If the waiting task gets killed by the oom
killer it would block oom_reaper from asynchronous address space reclaim
and reduce the chances of timely OOM resolving. Wait for the lock in
the killable mode and return with EINTR if the task got killed while
waiting.Signed-off-by: Michal Hocko
Acked-by: Andy Lutomirski [x86 vdso]
Acked-by: Vlastimil Babka
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
…unprotect)_crashkres()
Commit 3f625002581b ("kexec: introduce a protection mechanism for the
crashkernel reserved memory") is a similar mechanism for protecting the
crash kernel reserved memory to previous crash_map/unmap_reserved_pages()
implementation, the new one is more generic in name and cleaner in code
(besides, some arch may not be allowed to unmap the pgtable).Therefore, this patch consolidates them, and uses the new
arch_kexec_protect(unprotect)_crashkres() to replace former
crash_map/unmap_reserved_pages() which by now has been only used by
S390.The consolidation work needs the crash memory to be mapped initially,
this is done in machine_kdump_pm_init() which is after
reserve_crashkernel(). Once kdump kernel is loaded, the new
arch_kexec_protect_crashkres() implemented for S390 will actually
unmap the pgtable like before.Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Minfei Huang <mhuang@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
21 May, 2016
1 commit
-
We need to call exit_thread from copy_process in a fail path. So make it
accept task_struct as a parameter.[v2]
* s390: exit_thread_runtime_instr doesn't make sense to be called for
non-current tasks.
* arm: fix the comment in vfp_thread_copy
* change 'me' to 'tsk' for task_struct
* now we can change only archs that actually have exit_thread[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Jiri Slaby
Cc: "David S. Miller"
Cc: "H. Peter Anvin"
Cc: "James E.J. Bottomley"
Cc: Aurelien Jacquiot
Cc: Benjamin Herrenschmidt
Cc: Catalin Marinas
Cc: Chen Liqin
Cc: Chris Metcalf
Cc: Chris Zankel
Cc: David Howells
Cc: Fenghua Yu
Cc: Geert Uytterhoeven
Cc: Guan Xuetao
Cc: Haavard Skinnemoen
Cc: Hans-Christian Egtvedt
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Ivan Kokshaysky
Cc: James Hogan
Cc: Jeff Dike
Cc: Jesper Nilsson
Cc: Jiri Slaby
Cc: Jonas Bonn
Cc: Koichi Yasutake
Cc: Lennox Wu
Cc: Ley Foon Tan
Cc: Mark Salter
Cc: Martin Schwidefsky
Cc: Matt Turner
Cc: Max Filippov
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Mikael Starvik
Cc: Paul Mackerras
Cc: Peter Zijlstra
Cc: Ralf Baechle
Cc: Rich Felker
Cc: Richard Henderson
Cc: Richard Kuo
Cc: Richard Weinberger
Cc: Russell King
Cc: Steven Miao
Cc: Thomas Gleixner
Cc: Tony Luck
Cc: Vineet Gupta
Cc: Will Deacon
Cc: Yoshinori Sato
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
20 May, 2016
1 commit
-
…ernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible changes:
- Honour the kernel.perf_event_max_stack knob more precisely by not counting
PERF_CONTEXT_{KERNEL,USER} when deciding when to stop adding entries to
the perf_sample->ip_callchain[] array (Arnaldo Carvalho de Melo)- Fix identation of 'stalled-backend-cycles' in 'perf stat' (Namhyung Kim)
- Update runtime using 'cpu-clock' event in 'perf stat' (Namhyung Kim)
- Use 'cpu-clock' for cpu targets in 'perf stat' (Namhyung Kim)
- Avoid fractional digits for integer scales in 'perf stat' (Andi Kleen)
- Store vdso buildid unconditionally, as it appears in callchains and
we're not checking those when creating the build-id table, so we
end up not being able to resolve VDSO symbols when doing analysis
on a different machine than the one where recording was done, possibly
of a different arch even (arm -> x86_64) (He Kuang)Infrastructure changes:
- Generalize max_stack sysctl handler, will be used for configuring
multiple kernel knobs related to callchains (Arnaldo Carvalho de Melo)Cleanups:
- Introduce DSO__NAME_KALLSYMS and DSO__NAME_KCORE, to stop using
open coded strings (Masami Hiramatsu)Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
19 May, 2016
1 commit
-
Pull s390 updates from Martin Schwidefsky:
"The s390 patches for the 4.7 merge window have the usual bug fixes and
cleanups, and the following new features:- An interface for dasd driver to query if a volume is online to
another operating system- A new ioctl for the dasd driver to verify the format for a range of
tracks- Following the example of x86 the struct fpu is now allocated with
the task_struct- The 'report_error' interface for the PCI bus to send an
adapter-error notification from user space to the service element
of the machine"* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (29 commits)
s390/vmem: remove unused function parameter
s390/vmem: fix identity mapping
s390: add missing include statements
s390: add missing declarations
s390: make couple of variables and functions static
s390/cache: remove superfluous locking
s390/cpuinfo: simplify locking and skip offline cpus early
s390/3270: hangup the 3270 tty after a disconnect
s390/3270: handle reconnect of a tty with a different size
s390/3270: avoid endless I/O loop with disconnected 3270 terminals
s390/3270: fix garbled output on 3270 tty view
s390/3270: fix view reference counting
s390/3270: add missing tty_kref_put
s390/dumpstack: implement and use return_address()
s390/cpum_sf: Remove superfluous SMP function call
s390/cpum_cf: Remove superfluous SMP function call
s390/Kconfig: make z196 the default processor type
s390/sclp: avoid compile warning in sclp_pci_report
s390/fpu: allocate 'struct fpu' with the task_struct
s390/crypto: cleanup and move the header with the cpacf definitions
...
18 May, 2016
1 commit
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Pull livepatching updates from Jiri Kosina:
- remove of our own implementation of architecture-specific relocation
code and leveraging existing code in the module loader to perform
arch-dependent work, from Jessica Yu.The relevant patches have been acked by Rusty (for module.c) and
Heiko (for s390).- live patching support for ppc64le, which is a joint work of Michael
Ellerman and Torsten Duwe. This is coming from topic branch that is
share between livepatching.git and ppc tree.- addition of livepatching documentation from Petr Mladek
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
livepatch: make object/func-walking helpers more robust
livepatch: Add some basic livepatch documentation
powerpc/livepatch: Add live patching support on ppc64le
powerpc/livepatch: Add livepatch stack to struct thread_info
powerpc/livepatch: Add livepatch header
livepatch: Allow architectures to specify an alternate ftrace location
ftrace: Make ftrace_location_range() global
livepatch: robustify klp_register_patch() API error checking
Documentation: livepatch: outline Elf format and requirements for patch modules
livepatch: reuse module loader code to write relocations
module: s390: keep mod_arch_specific for livepatch modules
module: preserve Elf information for livepatch modules
Elf: add livepatch-specific Elf constants
17 May, 2016
1 commit
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This makes perf_callchain_{user,kernel}() receive the max stack
as context for the perf_callchain_entry, instead of accessing
the global sysctl_perf_event_max_stack.Cc: Adrian Hunter
Cc: Alexander Shishkin
Cc: Alexei Starovoitov
Cc: Brendan Gregg
Cc: David Ahern
Cc: Frederic Weisbecker
Cc: He Kuang
Cc: Jiri Olsa
Cc: Linus Torvalds
Cc: Masami Hiramatsu
Cc: Milian Wolff
Cc: Namhyung Kim
Cc: Peter Zijlstra
Cc: Stephane Eranian
Cc: Thomas Gleixner
Cc: Vince Weaver
Cc: Wang Nan
Cc: Zefan Li
Link: http://lkml.kernel.org/n/tip-kolmn1yo40p7jhswxwrc7rrd@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo
10 May, 2016
5 commits
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arch_mmap_rnd, cpu_have_feature, and arch_randomize_brk are all
defined as globally visible variables.
However the files they are defined in do not include the header files
with the declaration. To avoid a possible mismatch add the missing
include statements so we have proper type checking in place.Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky -
arch_dup_task_struct and the per cpu variable mt_cycles are globally
visible, but do not have any header file with a declaration.
Therefore add it so we have proper type checking in place.Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky -
copy_oldmem_user() and ap_jumptable are private to the files they are
being used in. Therefore make them static.Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky -
With "s390/cpuinfo: simplify locking and skip offline cpus early" we
prevent already that cpus will go away. The additional
get_online_cpus() / put_online_cpus() within show_cacheinfo() is not
needed anymore.Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky -
Move the get_online_cpus() and put_online_cpus() to the start and stop
operation of the seqfile ops. This way there is no need to lock cpu
hotplug again and again for each single cpu.This way we can also skip offline cpus early if we simply use
cpumask_next() within the next operation.Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky
06 May, 2016
1 commit
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In order to enable symmetric hotplug, we must mirror the online &&
!active state of cpu-down on the cpu-up side.However, to retain sanity, limit this state to per-cpu kthreads.
Aside from the change to set_cpus_allowed_ptr(), which allow moving
the per-cpu kthreads on, the other critical piece is the cpu selection
for pinned tasks in select_task_rq(). This avoids dropping into
select_fallback_rq().select_fallback_rq() cannot be allowed to select !active cpus because
its used to migrate user tasks away. And we do not want to move user
tasks onto cpus that are in transition.Requested-by: Thomas Gleixner
Signed-off-by: Peter Zijlstra (Intel)
Tested-by: Thomas Gleixner
Cc: Lai Jiangshan
Cc: Jan H. Schönherr
Cc: Oleg Nesterov
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160301152303.GV6356@twins.programming.kicks-ass.net
Signed-off-by: Thomas Gleixner
04 May, 2016
1 commit
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Implement return_address() and use it instead of __builtin_return_address(n).
__builtin_return_address(n) is not guaranteed to work for n > 0,
therefore implement a private return_address() function which walks
the stack frames and returns the proper return address.This way we get also rid of a compile warning which gcc 6.1 emits and
look like all other architectures.Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky
03 May, 2016
2 commits
-
Since commit 3b9d6da67e11 ("cpu/hotplug: Fix rollback during error-out
in __cpu_disable()") it is ensured that callbacks of CPU_ONLINE and
CPU_DOWN_PREPARE are processed on the hotplugged CPU. Due to this SMP
function calls are no longer required.Replace smp_call_function_single() with a direct call of
setup_pmc_cpu(). To keep the calling convention, interrupts are
explicitly disabled around the call.Cc: linux-s390@vger.kernel.org
Signed-off-by: Anna-Maria Gleixner
Acked-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky -
Since commit 3b9d6da67e11 ("cpu/hotplug: Fix rollback during error-out
in __cpu_disable()") it is ensured that callbacks of CPU_ONLINE and
CPU_DOWN_PREPARE are processed on the hotplugged CPU. Due to this SMP
function calls are no longer required.Replace smp_call_function_single() with a direct call of
setup_pmc_cpu(). To keep the calling convention, interrupts are
explicitly disabled around the call.Cc: linux-s390@vger.kernel.org
Signed-off-by: Anna-Maria Gleixner
Acked-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky
21 Apr, 2016
1 commit
-
Analog to git commit 0c8c0f03e3a292e031596484275c14cf39c0ab7a
"x86/fpu, sched: Dynamically allocate 'struct fpu'"
move the struct fpu to the end of the struct thread_struct,
set CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and add the
setup_task_size() function to calculate the correct size
fo the task struct.For the performance_defconfig this increases the size of
struct task_struct from 7424 bytes to 7936 bytes (MACHINE_HAS_VX==1)
or 7552 bytes (MACHINE_HAS_VX==0). The dynamic allocation of the
struct fpu is removed. The slab cache uses an 8KB block for the
task struct in all cases, there is enough room for the struct fpu.
For MACHINE_HAS_VX==1 each task now needs 512 bytes less memory.Signed-off-by: Martin Schwidefsky
01 Apr, 2016
3 commits
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Livepatch needs to utilize the symbol information contained in the
mod_arch_specific struct in order to be able to call the s390
apply_relocate_add() function to apply relocations. Keep a reference to
syminfo if the module is a livepatch module. Remove the redundant vfree()
in module_finalize() since module_arch_freeing_init() (which also frees
those structures) is called in do_init_module(). If the module isn't a
livepatch module, we free the structures in module_arch_freeing_init() as
usual.Signed-off-by: Jessica Yu
Reviewed-by: Miroslav Benes
Acked-by: Josh Poimboeuf
Acked-by: Heiko Carstens
Signed-off-by: Jiri Kosina -
Pull s390 fixes from Martin Schwidefsky:
- A proper fix for the locking issue in the dasd driver
- Wire up the new preadv2 nad pwritev2 system calls
- Add the mark_rodata_ro function and set DEBUG_RODATA=y
- A few more bug fixes.* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390: wire up preadv2/pwritev2 syscalls
s390/pci: PCI function group 0 is valid for clp_query_pci_fn
s390/crypto: provide correct file mode at device register.
s390/mm: handle PTE-mapped tail pages in fast gup
s390: add DEBUG_RODATA support
s390: disable postinit-readonly for now
s390/dasd: reorder lcu and device lock
s390/cpum_sf: Fix cpu hotplug notifier transitions
s390/cpum_cf: Fix missing cpu hotplug notifier transition -
Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky
26 Mar, 2016
1 commit
-
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.Move the definition of __irq_entry to so that the
users don't need to pull in . Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.Signed-off-by: Alexander Potapenko
Acked-by: Steven Rostedt
Cc: Christoph Lameter
Cc: Pekka Enberg
Cc: David Rientjes
Cc: Joonsoo Kim
Cc: Andrey Konovalov
Cc: Dmitry Vyukov
Cc: Andrey Ryabinin
Cc: Konstantin Serebryany
Cc: Dmitry Chernenkov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
18 Mar, 2016
1 commit
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This changes several users of manual "on"/"off" parsing to use
strtobool.Some side-effects:
- these uses will now parse y/n/1/0 meaningfully too
- the early_param uses will now bubble up parse errorsSigned-off-by: Kees Cook
Acked-by: Heiko Carstens
Acked-by: Michael Ellerman
Cc: Amitkumar Karwar
Cc: Andy Shevchenko
Cc: Daniel Borkmann
Cc: Joe Perches
Cc: Kalle Valo
Cc: Martin Schwidefsky
Cc: Nishant Sarmukadam
Cc: Rasmus Villemoes
Cc: Steve French
Cc: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
17 Mar, 2016
4 commits
-
The cpumf_pmu_notfier() hotplug callback lacks handling of the
CPU_DOWN_FAILED case. That means, if CPU_DOWN_PREPARE failes, the PMC
of the CPU is not setup again. Furthermore the CPU_ONLINE_FROZEN case
will never be processed because of masking the switch expression with
CPU_TASKS_FROZEN.Add handling for CPU_DOWN_FAILED transition to setup the PMC of the
CPU. Remove CPU_ONLINE_FROZEN case.Signed-off-by: Anna-Maria Gleixner
Acked-by: Hendrik Brueckner
Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky -
The cpumf_pmu_notfier() hotplug callback lacks handling of the
CPU_DOWN_FAILED case. That means, if CPU_DOWN_PREPARE failes, the PMC
of the CPU is not setup again.Add handling for CPU_DOWN_FAILED transition to setup the PMC of the
CPU.Signed-off-by: Anna-Maria Gleixner
Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky -
Merge first patch-bomb from Andrew Morton:
- some misc things
- ofs2 updates
- about half of MM
- checkpatch updates
- autofs4 update
* emailed patches from Andrew Morton : (120 commits)
autofs4: fix string.h include in auto_dev-ioctl.h
autofs4: use pr_xxx() macros directly for logging
autofs4: change log print macros to not insert newline
autofs4: make autofs log prints consistent
autofs4: fix some white space errors
autofs4: fix invalid ioctl return in autofs4_root_ioctl_unlocked()
autofs4: fix coding style line length in autofs4_wait()
autofs4: fix coding style problem in autofs4_get_set_timeout()
autofs4: coding style fixes
autofs: show pipe inode in mount options
kallsyms: add support for relative offsets in kallsyms address table
kallsyms: don't overload absolute symbol type for percpu symbols
x86: kallsyms: disable absolute percpu symbols on !SMP
checkpatch: fix another left brace warning
checkpatch: improve UNSPECIFIED_INT test for bare signed/unsigned uses
checkpatch: warn on bare unsigned or signed declarations without int
checkpatch: exclude asm volatile from complex macro check
mm: memcontrol: drop unnecessary lru locking from mem_cgroup_migrate()
mm: migrate: consolidate mem_cgroup_migrate() calls
mm/compaction: speed up pageblock_pfn_to_page() when zone is contiguous
... -
Pull s390 updates from Martin Schwidefsky:
- Add the CPU id for the new z13s machine
- Add a s390 specific XOR template for RAID-5 checksumming based on the
XC instruction. Remove all other alternatives, XC is always faster- The merge of our four different stack tracers into a single one
- Tidy up the code related to page tables, several large inline
functions are now out-of-line. Bloat-o-meter reports ~11K text size
reduction- A binary interface for the priviledged CLP instruction to retrieve
the hardware view of the installed PCI functions- Improvements for the dasd format code
- Bug fixes and cleanups
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (31 commits)
s390/pci: enforce fmb page boundary rule
s390: fix floating pointer register corruption (again)
s390/cpumf: add missing lpp magic initialization
s390: Fix misspellings in comments
s390/mm: split arch/s390/mm/pgtable.c
s390/mm: uninline pmdp_xxx functions from pgtable.h
s390/mm: uninline ptep_xxx functions from pgtable.h
s390/pci: add ioctl interface for CLP
s390: Use pr_warn instead of pr_warning
s390/dasd: remove casts to dasd_*_private
s390/dasd: Refactor dasd format functions
s390/dasd: Simplify code in format logic
s390/dasd: Improve dasd format code
s390/percpu: remove this_cpu_cmpxchg_double_4
s390/cpumf: Improve guest detection heuristics
s390/fault: merge report_user_fault implementations
s390/dis: use correct escape sequence for '%' character
s390/kvm: simplify set_guest_storage_key
s390/oprofile: add z13/z13s model numbers
s390: add z13s model number to z13 elf platform
...
16 Mar, 2016
2 commits
-
We can use debug_pagealloc_enabled() to check if we can map the identity
mapping with 1MB/2GB pages as well as to print the current setting in
dump_stack.Signed-off-by: Christian Borntraeger
Reviewed-by: Heiko Carstens
Cc: Thomas Gleixner
Acked-by: David Rientjes
Cc: Laura Abbott
Cc: Joonsoo Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Pull cpu hotplug updates from Thomas Gleixner:
"This is the first part of the ongoing cpu hotplug rework:- Initial implementation of the state machine
- Runs all online and prepare down callbacks on the plugged cpu and
not on some random processor- Replaces busy loop waiting with completions
- Adds tracepoints so the states can be followed"
More detailed commentary on this work from an earlier email:
"What's wrong with the current cpu hotplug infrastructure?- Asymmetry
The hotplug notifier mechanism is asymmetric versus the bringup and
teardown. This is mostly caused by the notifier mechanism.- Largely undocumented dependencies
While some notifiers use explicitely defined notifier priorities,
we have quite some notifiers which use numerical priorities to
express dependencies without any documentation why.- Control processor driven
Most of the bringup/teardown of a cpu is driven by a control
processor. While it is understandable, that preperatory steps,
like idle thread creation, memory allocation for and initialization
of essential facilities needs to be done before a cpu can boot,
there is no reason why everything else must run on a control
processor. Before this patch series, bringup looks like this:Control CPU Booting CPU
do preparatory steps
kick cpu into lifedo low level init
sync with booting cpu sync with control cpu
bring the rest up
- All or nothing approach
There is no way to do partial bringups. That's something which is
really desired because we waste e.g. at boot substantial amount of
time just busy waiting that the cpu comes to life. That's stupid
as we could very well do preparatory steps and the initial IPI for
other cpus and then go back and do the necessary low level
synchronization with the freshly booted cpu.- Minimal debuggability
Due to the notifier based design, it's impossible to switch between
two stages of the bringup/teardown back and forth in order to test
the correctness. So in many hotplug notifiers the cancel
mechanisms are either not existant or completely untested.- Notifier [un]registering is tedious
To [un]register notifiers we need to protect against hotplug at
every callsite. There is no mechanism that bringup/teardown
callbacks are issued on the online cpus, so every caller needs to
do it itself. That also includes error rollback.What's the new design?
The base of the new design is a symmetric state machine, where both
the control processor and the booting/dying cpu execute a well
defined set of states. Each state is symmetric in the end, except
for some well defined exceptions, and the bringup/teardown can be
stopped and reversed at almost all states.So the bringup of a cpu will look like this in the future:
Control CPU Booting CPU
do preparatory steps
kick cpu into lifedo low level init
sync with booting cpu sync with control cpu
bring itself up
The synchronization step does not require the control cpu to wait.
That mechanism can be done asynchronously via a worker or some
other mechanism.The teardown can be made very similar, so that the dying cpu cleans
up and brings itself down. Cleanups which need to be done after
the cpu is gone, can be scheduled asynchronously as well.There is a long way to this, as we need to refactor the notion when a
cpu is available. Today we set the cpu online right after it comes
out of the low level bringup, which is not really correct.The proper mechanism is to set it to available, i.e. cpu local
threads, like softirqd, hotplug thread etc. can be scheduled on that
cpu, and once it finished all booting steps, it's set to online, so
general workloads can be scheduled on it. The reverse happens on
teardown. First thing to do is to forbid scheduling of general
workloads, then teardown all the per cpu resources and finally shut it
off completely.This patch series implements the basic infrastructure for this at the
core level. This includes the following:- Basic state machine implementation with well defined states, so
ordering and prioritization can be expressed.- Interfaces to [un]register state callbacks
This invokes the bringup/teardown callback on all online cpus with
the proper protection in place and [un]installs the callbacks in
the state machine array.For callbacks which have no particular ordering requirement we have
a dynamic state space, so that drivers don't have to register an
explicit hotplug state.If a callback fails, the code automatically does a rollback to the
previous state.- Sysfs interface to drive the state machine to a particular step.
This is only partially functional today. Full functionality and
therefor testability will be achieved once we converted all
existing hotplug notifiers over to the new scheme.- Run all CPU_ONLINE/DOWN_PREPARE notifiers on the booting/dying
processor:Control CPU Booting CPU
do preparatory steps
kick cpu into lifedo low level init
sync with booting cpu sync with control cpu
wait for boot
bring itself upSignal completion to control cpu
In a previous step of this work we've done a full tree mechanical
conversion of all hotplug notifiers to the new scheme. The balance
is a net removal of about 4000 lines of code.This is not included in this series, as we decided to take a
different approach. Instead of mechanically converting everything
over, we will do a proper overhaul of the usage sites one by one so
they nicely fit into the symmetric callback scheme.I decided to do that after I looked at the ugliness of some of the
converted sites and figured out that their hotplug mechanism is
completely buggered anyway. So there is no point to do a
mechanical conversion first as we need to go through the usage
sites one by one again in order to achieve a full symmetric and
testable behaviour"* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
cpu/hotplug: Document states better
cpu/hotplug: Fix smpboot thread ordering
cpu/hotplug: Remove redundant state check
cpu/hotplug: Plug death reporting race
rcu: Make CPU_DYING_IDLE an explicit call
cpu/hotplug: Make wait for dead cpu completion based
cpu/hotplug: Let upcoming cpu bring itself fully up
arch/hotplug: Call into idle with a proper state
cpu/hotplug: Move online calls to hotplugged cpu
cpu/hotplug: Create hotplug threads
cpu/hotplug: Split out the state walk into functions
cpu/hotplug: Unpark smpboot threads from the state machine
cpu/hotplug: Move scheduler cpu_online notifier to hotplug core
cpu/hotplug: Implement setup/removal interface
cpu/hotplug: Make target state writeable
cpu/hotplug: Add sysfs state interface
cpu/hotplug: Hand in target state to _cpu_up/down
cpu/hotplug: Convert the hotplugged cpu work to a state machine
cpu/hotplug: Convert to a state machine for the control processor
cpu/hotplug: Add tracepoints
...
15 Mar, 2016
2 commits
-
Pull locking changes from Ingo Molnar:
"Various updates:- Futex scalability improvements: remove page lock use for shared
futex get_futex_key(), which speeds up 'perf bench futex hash'
benchmarks by over 40% on a 60-core Westmere. This makes anon-mem
shared futexes perform close to private futexes. (Mel Gorman)- lockdep hash collision detection and fix (Alfredo Alvarez
Fernandez)- lockdep testing enhancements (Alfredo Alvarez Fernandez)
- robustify lockdep init by using hlists (Andrew Morton, Andrey
Ryabinin)- mutex and csd_lock micro-optimizations (Davidlohr Bueso)
- small x86 barriers tweaks (Michael S Tsirkin)
- qspinlock updates (Waiman Long)"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
locking/csd_lock: Use smp_cond_acquire() in csd_lock_wait()
locking/csd_lock: Explicitly inline csd_lock*() helpers
futex: Replace barrier() in unqueue_me() with READ_ONCE()
locking/lockdep: Detect chain_key collisions
locking/lockdep: Prevent chain_key collisions
tools/lib/lockdep: Fix link creation warning
tools/lib/lockdep: Add tests for AA and ABBA locking
tools/lib/lockdep: Add userspace version of READ_ONCE()
tools/lib/lockdep: Fix the build on recent kernels
locking/qspinlock: Move __ARCH_SPIN_LOCK_UNLOCKED to qspinlock_types.h
locking/mutex: Allow next waiter lockless wakeup
locking/pvqspinlock: Enable slowpath locking count tracking
locking/qspinlock: Use smp_cond_acquire() in pending code
locking/pvqspinlock: Move lock stealing count tracking code into pv_queued_spin_steal_lock()
locking/mcs: Fix mcs_spin_lock() ordering
futex: Remove requirement for lock_page() in get_futex_key()
futex: Rename barrier references in ordering guarantees
locking/atomics: Update comment about READ_ONCE() and structures
locking/lockdep: Eliminate lockdep_init()
locking/lockdep: Convert hash tables to hlists
... -
Pull ram resource handling changes from Ingo Molnar:
"Core kernel resource handling changes to support NVDIMM error
injection.This tree introduces a new I/O resource type, IORESOURCE_SYSTEM_RAM,
for System RAM while keeping the current IORESOURCE_MEM type bit set
for all memory-mapped ranges (including System RAM) for backward
compatibility.With this resource flag it no longer takes a strcmp() loop through the
resource tree to find "System RAM" resources.The new resource type is then used to extend ACPI/APEI error injection
facility to also support NVDIMM"* 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ACPI/EINJ: Allow memory error injection to NVDIMM
resource: Kill walk_iomem_res()
x86/kexec: Remove walk_iomem_res() call with GART type
x86, kexec, nvdimm: Use walk_iomem_res_desc() for iomem search
resource: Add walk_iomem_res_desc()
memremap: Change region_intersects() to take @flags and @desc
arm/samsung: Change s3c_pm_run_res() to use System RAM type
resource: Change walk_system_ram() to use System RAM type
drivers: Initialize resource entry to zero
xen, mm: Set IORESOURCE_SYSTEM_RAM to System RAM
kexec: Set IORESOURCE_SYSTEM_RAM for System RAM
arch: Set IORESOURCE_SYSTEM_RAM flag for System RAM
ia64: Set System RAM type and descriptor
x86/e820: Set System RAM type and descriptor
resource: Add I/O resource descriptor
resource: Handle resource flags properly
resource: Add System RAM resource type
10 Mar, 2016
2 commits
-
There is a tricky interaction between the machine check handler
and the critical sections of load_fpu_regs and save_fpu_regs
functions. If the machine check interrupts one of the two
functions the critical section cleanup will complete the function
before the machine check handler s390_do_machine_check is called.
Trouble is that the machine check handler needs to validate the
floating point registers *before* and not *after* the completion
of load_fpu_regs/save_fpu_regs.The simplest solution is to rewind the PSW to the start of the
load_fpu_regs/save_fpu_regs and retry the function after the
return from the machine check handler.Tested-by: Christian Borntraeger
Cc: # 4.3+
Signed-off-by: Martin Schwidefsky -
Add the missing lpp magic initialization for cpu 0. Without this all
samples on cpu 0 do not have the most significant bit set in the
program parameter field, which we use to distinguish between guest and
host samples if the pid is also 0.We did initialize the lpp magic in the absolute zero lowcore but
forgot that when switching to the allocated lowcore on cpu 0 only.Reported-by: Shu Juan Zhang
Acked-by: Christian Borntraeger
Cc: stable@vger.kernel.org # v4.4+
Fixes: e22cf8ca6f75 ("s390/cpumf: rework program parameter setting to detect guest samples")
Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky
08 Mar, 2016
3 commits
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Signed-off-by: Adam Buchbinder
Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky -
The pgtable.c file is quite big, before it grows any larger split it
into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related
header definitions into the new gmap.h header and all of the pgste
helpers from pgtable.h to pgtable.c.Signed-off-by: Martin Schwidefsky
-
we have to check bit 40 of the facility list before issuing LPP
and not bit 48. Otherwise a guest running on a system with
"The decimal-floating-point zoned-conversion facility" and without
the "The set-program-parameters facility" might crash on an lpp
instruction.Signed-off-by: Christian Borntraeger
Cc: stable@vger.kernel.org # v4.4+
Fixes: e22cf8ca6f75 ("s390/cpumf: rework program parameter setting to detect guest samples")
Signed-off-by: Martin Schwidefsky
07 Mar, 2016
1 commit
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Convert the uses of pr_warning to pr_warn so there are fewer
uses of the old pr_warning.Miscellanea:
o Align arguments
o Coalesce formatsSigned-off-by: Joe Perches
Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky
04 Mar, 2016
1 commit
-
Signed-off-by: Ingo Molnar