ARC HS Cores support configurable multiple interrupt priorities of upto
16 levels. In commit dec2b2849c ("ARCv2: intc: Allow interruption by
lowest priority interrupt") we switched to 15 which seems a bit
excessive given that there would be rare hardware implementing so many
preemption levels AND running Linux. It would seem that 2 levels will be
more common so switch to 1 as the default priority level. This will be
the "lower" priority level saving 0 for implementing NMI style support.
This scheme also works in systems with more than 2 prioity levels as
well.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Also remove the dependency on ARCv2, to increase compile coverage for
!ARCV2 builds
Acked-by: Daniel Lezcano <daniel.lezcnao@linaro.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC timers use aux registers for programming and this paves way for
moving ARC timer drivers into drivers/clocksource
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
commit 1c3c909303 broke PAE40. Macro pfn_pte(pfn, prot) creates paddr
from pfn, but the page shift was getting truncated to 32 bits since we lost
the proper cast to 64 bits (for PAE400
Instead of reverting that commit, use a better helper which is 32/64 bits
safe just like ARM implementation.
Fixes: 1c3c909303 ("ARC: mm: fix build breakage with STRICT_MM_TYPECHECKS")
Cc: <stable@vger.kernel.org> #4.4+
Signed-off-by: Yuriy Kolerov <yuriy.kolerov@synopsys.com>
[vgupta: massaged changelog]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Apparenty this is coming in the way of gcc fix which inhibits the usage
of LP_COUNT as a gpr.
Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This came up when reviewing code to address missing IRQ affinity
setting in AXS103 platform and/or implementing hierarchical IRQ domains
- smp_ipi_irq_setup() callers pass hwirq but in turn calls
request_percpu_irq() which expects a linux virq. So invoke
irq_find_mapping() to do the conversion
(also explicitify this in code by renaming the args appropriately)
- idu_of_init()/idu_cascade_isr() were similarly using linux virq where
hwirq is expected, so do the conversion using irqd_to_hwirq() helper
Signed-off-by: Yuriy Kolerov <yuriy.kolerov@synopsys.com>
[vgupta: made changelog a bit concise a bit]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The original syscall only used to return errno to indicate if cmpxchg
succeeded. It was not returning the "previous" value which typical cmpxchg
callers are interested in to build their slowpaths or retry loops.
Given user preemption in syscall return path etc, it is not wise to
check this in userspace afterwards, but should be what kernel actually
observed in the syscall.
So change the syscall interface to always return the previous value and
additionally set Z flag to indicate whether operation succeeded or not
(just like ARM implementation when they used to have this syscall)
The flag approach avoids having to put_user errno which is nice given
the use case for this syscall cares mostly about the "previous" value.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The loop was really needed in .debug_frame regime where wanted make it
as SH_ALLOC so that apply_relocate_add() would process it. That's not
needed for .eh_frame, so we check this in apply_relocate_add() which
gets called for each section.
Note that we need to save reference to "section name strings" section in
module_frob_arch_sections() since apply_relocate_add() doesn't get that
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The motivation is to identify ARC750 vs. ARC770 (we currently print
generic "ARC700").
A given ARC700 release could be 750 or 770, with same ARCNUM (or family
identifier which is unfortunate). The existing arc_cpu_tbl[] kept a single
concatenated string for core name and release which thus doesn't work
for 750 vs. 770 identification.
So split this into 2 tables, one with core names and other with release.
And while we are at it, get rid of the range checking for family numbers.
We just document the known to exist cores running Linux and ditch
others.
With this in place, we add detection of ARC750 which is
- cores 0x33 and before
- cores 0x34 and later with MMUv2
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This came to light when helping a customer with oldish ARC750 core who
were getting instruction errors because of lack of SWAPE but boot log
was incorrectly printing it as being present
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
On older arc700 cores, some of the features configured were not present
in Build config registers. To print about them at boot, we just use the
Kconfig option i.e. whether linux is built to use them or not.
So yes this seems bogus, but what else can be done. Moreover if linux is
booting with these enabled, then the Kconfig info is a good indicator
anyways.
Over time these "hacks" accumulated in read_arc_build_cfg_regs() as well
as arc_cpu_mumbojumbo(). so refactor and move all of those in a single
place: read_arc_build_cfg_regs(). This causes some code redcution too:
| bloat-o-meter2 arch/arc/kernel/setup.o.0 arch/arc/kernel/setup.o.1
| add/remove: 0/0 grow/shrink: 2/1 up/down: 64/-132 (-68)
| function old new delta
| setup_processor 610 670 +60
| cpuinfo_arc700 76 80 +4
| arc_cpu_mumbojumbo 752 620 -132
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Previously we would not print the case when IOC existed but was not
enabled.
And while at it, reduce one line off boot printing by consolidating
the Peripheral address space and IO-Coherency which in a way
applies to them
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
if user disables IOC from debugger at startup (by clearing @ioc_enable),
@ioc_exists is cleared too. This means boot prints don't capture the
fact that IOC was present but disabled which could be misleading.
So invert how we use @ioc_enable and @ioc_exists and make it more
canonical. @ioc_exists represent whether hardware is present or not and
stays same whether enabled or not. @ioc_enable is still user driven,
but will be auto-disabled if IOC hardware is not present, i.e. if
@ioc_exist=0. This is opposite to what we were doing before, but much
clearer.
This means @ioc_enable is now the "exported" toggle in rest of code such
as dma mapping API.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Older ARC700 cores (ARC750 specifically) lack instructions to implement
atomic r-w-w. This is problematic for userspace libraries such as NPTL
which need atomic primitives. So enable them by providing kernel assist.
This is costly but really the only sane soluton (othern than tight
spinning using the otherwise availiable atomic exchange EX instruciton).
Good thing is there are only a few of these cores running Linux out in
the wild.
This only works on UP systems.
Reviewed-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The cast valid since TASK_SIZE * 2 will never actually cause overflow.
| CC fs/binfmt_elf.o
| In file included from ../include/linux/elf.h:4:0,
| from ../include/linux/module.h:15,
| from ../fs/binfmt_elf.c:12:
| ../fs/binfmt_elf.c: In function load_elf_binar:
| ../arch/arc/include/asm/elf.h:57:29: warning: integer overflow in expression [-Woverflow]
| #define ELF_ET_DYN_BASE (2 * TASK_SIZE / 3)
| ^
| ../fs/binfmt_elf.c:921:16: note: in expansion of macro ELF_ET_DYN_BASE
| load_bias = ELF_ET_DYN_BASE - vaddr;
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The IDU intc is technically part of MCIP (Multi-core IP) hence
historically was only available in a SMP hardware build (and thus only
in a SMP kernel build). Now that hardware restriction has been lifted,
so a UP kernel needs to support it.
This requires breaking mcip.c into parts which are strictly SMP
(inter-core interrupts) and IDU which in reality is just another
intc and thus has no bearing on SMP.
This change allows IDU in UP builds and with a suitable device tree, we
can have the cascaded intc system
ARCv2 core intc <---> ARCv2 IDU intc <---> periperals
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Commit d9676fa152 ("ARCv2: Enable LOCKDEP"), changed
local_save_flags() to not return raw STATUS32 but encoded in the form
such that it could be fed directly to CLRI/SETI instructions.
However the STATUS32.E[] was not captured correctly as it corresponds to
bits [4:1] in the register and not [3:0]
Fixes: d9676fa152 ("ARCv2: Enable LOCKDEP")
Cc: Evgeny Voevodin <evgeny.voevodin@intel.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
1. detect whether binutils supports the cfi pseudo ops
2. define conditional macros to generate the ops
3. define new ENTRY_CFI/END_CFI to annotate hand asm code.
- Needed because we don't want to emit dwarf info in general ENTRY/END
used by lowest level trap/exception/interrutp handlers as unwinder
gets confused trying to unwind out of them. We want unwinder to
instead stop when it hits onfo those routines
- These provide minimal start/end cfi ops assuming routine doesn't
touch stack memory/regs
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
We used to live with PERF_COUNT_HW_CACHE_REFERENCES and
PERF_COUNT_HW_CACHE_REFERENCES not specified on ARC.
Those events are actually aliases to 2 cache events that we do support
and so this change sets "cache-reference" and "cache-misses" events
in the same way as "L1-dcache-loads" and L1-dcache-load-misses.
And while at it adding debug info for cache events as well as doing a
subtle fix in HW events debug info - config value is much better
represented by hex so we may see not only event index but as well other
control bits set (if they exist).
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Build brekeage since last changes to generic atomic operations.
Added couple of missing macros which are now mandatory
Signed-off-by: Noam Camus <noamca@mellanox.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARCv2 ISA provides 64-bit exclusive load/stores so use them to implement
the 64-bit atomics and elide the spinlock based generic 64-bit atomics
boot tested with atomic64 self-test (and GOD bless the person who wrote
them, I realized my inline assmebly is sloppy as hell)
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
HS release 3.0 provides for even more flexibility in specifying the
volatile address space for mapping peripherals.
With HS 2.1 @start was made flexible / programmable - with HS 3.0 even
@end can be setup (vs. fixed to 0xFFFF_FFFF before).
So add code to reflect that and while at it remove an unused struct
defintion
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Pull uaccess fixes from Al Viro:
"Fixes for broken uaccess primitives - mostly lack of proper zeroing
in copy_from_user()/get_user()/__get_user(), but for several
architectures there's more (broken clear_user() on frv and
strncpy_from_user() on hexagon)"
* 'uaccess-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits)
avr32: fix copy_from_user()
microblaze: fix __get_user()
microblaze: fix copy_from_user()
m32r: fix __get_user()
blackfin: fix copy_from_user()
sparc32: fix copy_from_user()
sh: fix copy_from_user()
sh64: failing __get_user() should zero
score: fix copy_from_user() and friends
score: fix __get_user/get_user
s390: get_user() should zero on failure
ppc32: fix copy_from_user()
parisc: fix copy_from_user()
openrisc: fix copy_from_user()
nios2: fix __get_user()
nios2: copy_from_user() should zero the tail of destination
mn10300: copy_from_user() should zero on access_ok() failure...
mn10300: failing __get_user() and get_user() should zero
mips: copy_from_user() must zero the destination on access_ok() failure
ARC: uaccess: get_user to zero out dest in cause of fault
...
Add ARC as an arch that supports PCI_MSI_IRQ_DOMAIN and add generation of
msi.h in the ARC arch.
Signed-off-by: Joao Pinto <jpinto@synopsys.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
| CC mm/memory.o
| In file included from ../mm/memory.c:53:0:
| ../include/linux/pfn_t.h: In function ‘pfn_t_pte’:
| ../include/linux/pfn_t.h:78:2: error: conversion to non-scalar type requested
| return pfn_pte(pfn_t_to_pfn(pfn), pgprot);
With STRICT_MM_TYPECHECKS pte_t is a struct and the offending code
forces a cast which ends up shifting a struct and hence the gcc warning.
Note that in recent past some of the arches (aarch64, s390) made
STRICT_MM_TYPECHECKS default, but we don't for ARC as this leads to slightly
worse generated code, given ARC ABI definition of returning structs
(which pte_t would become)
Quoting from ARC ABI...
"Results of type struct are returned in a caller-supplied temporary
variable whose address is passed in r0.
For such functions, the arguments are shifted so that they are
passed in r1 and up."
So
- struct to be returned would be allocated on stack requiring extra
code at call sites
- callee updates stack memory to facilitate the return (vs. simple
MOV into return reg r0)
Hence STRICT_MM_TYPECHECKS is not enabled by default for ARC
Cc: <stable@vger.kernel.org> #4.4+
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
The syscall ABI includes the gcc functional calling ABI since a syscall
implies userland caller and kernel callee.
The current gcc ABI (v3) for ARCv2 ISA required 64-bit data be passed in
even-odd register pairs, (potentially punching reg holes when passing such
values as args). This was partly driven by the fact that the double-word
LDD/STD instructions in ARCv2 expect the register alignment and thus gcc
forcing this avoids extra MOV at the cost of a few unused register (which we
have plenty anyways).
This however was rejected as part of upstreaming gcc port to HS. So the new
ABI v4 doesn't enforce the even-odd reg restriction.
Do note that for ARCompact ISA builds v3 and v4 are practically the same in
terms of gcc code generation.
In terms of change management, we infer the new ABI if gcc 6.x onwards
is used for building the kernel.
This also needs a stable backport to enable older kernels to work with
new tools/user-space
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
User mode callee regs are explicitly collected before signal delivery or
breakpoint trap. r25 is special for kernel as it serves as task pointer,
so user mode value is clobbered very early. It is saved in pt_regs where
generally only scratch (aka caller saved) regs are saved.
The code to access the corresponding pt_regs location had a subtle bug as
it was using load/store with scaling of offset, whereas the offset was already
byte wise correct. So fix this by replacing LD.AS with a standard LD
Cc: <stable@vger.kernel.org>
Signed-off-by: Liav Rehana <liavr@mellanox.com>
Reviewed-by: Alexey Brodkin <abrodkin@synopsys.com>
[vgupta: rewrote title and commit log]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
trace_hardirqs_on_caller() in lockdep.c expects to be called before, not
after interrupts are actually enabled.
The following comment in kernel/locking/lockdep.c substantiates this
claim:
"
/*
* We're enabling irqs and according to our state above irqs weren't
* already enabled, yet we find the hardware thinks they are in fact
* enabled.. someone messed up their IRQ state tracing.
*/
"
An example can be found in include/linux/irqflags.h:
do { trace_hardirqs_on(); raw_local_irq_enable(); } while (0)
Without this change, we hit the following DEBUG_LOCKS_WARN_ON.
[ 7.760000] ------------[ cut here ]------------
[ 7.760000] WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:2711 resume_user_mode_begin+0x48/0xf0
[ 7.770000] DEBUG_LOCKS_WARN_ON(!irqs_disabled())
[ 7.780000] Modules linked in:
[ 7.780000] CPU: 0 PID: 1 Comm: init Not tainted 4.7.0-00003-gc668bb9-dirty #366
[ 7.790000]
[ 7.790000] Stack Trace:
[ 7.790000] arc_unwind_core.constprop.1+0xa4/0x118
[ 7.800000] warn_slowpath_fmt+0x72/0x158
[ 7.800000] resume_user_mode_begin+0x48/0xf0
[ 7.810000] ---[ end trace 6f6a7a8fae20d2f0 ]---
Signed-off-by: Daniel Mentz <danielmentz@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Things have been calm here - nothing much except for a few fixes
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=/rhI
-----END PGP SIGNATURE-----
Merge tag 'arc-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC updates from Vineet Gupta:
"Things have been calm here - nothing much except for a few fixes"
* tag 'arc-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: mm: don't loose PTE_SPECIAL in pte_modify()
ARC: dma: fix address translation in arc_dma_free
ARC: typo fix in mm/ioremap.c
ARC: fix linux-next build breakage
LTP madvise05 was generating mm splat
| [ARCLinux]# /sd/ltp/testcases/bin/madvise05
| BUG: Bad page map in process madvise05 pte:80e08211 pmd:9f7d4000
| page:9fdcfc90 count:1 mapcount:-1 mapping: (null) index:0x0 flags: 0x404(referenced|reserved)
| page dumped because: bad pte
| addr:200b8000 vm_flags:00000070 anon_vma: (null) mapping: (null) index:1005c
| file: (null) fault: (null) mmap: (null) readpage: (null)
| CPU: 2 PID: 6707 Comm: madvise05
And for newer kernels, the system was rendered unusable afterwards.
The problem was mprotect->pte_modify() clearing PTE_SPECIAL (which is
set to identify the special zero page wired to the pte).
When pte was finally unmapped, special casing for zero page was not
done, and instead it was treated as a "normal" page, tripping on the
map counts etc.
This fixes ARC STAR 9001053308
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Pull locking updates from Ingo Molnar:
"The locking tree was busier in this cycle than the usual pattern - a
couple of major projects happened to coincide.
The main changes are:
- implement the atomic_fetch_{add,sub,and,or,xor}() API natively
across all SMP architectures (Peter Zijlstra)
- add atomic_fetch_{inc/dec}() as well, using the generic primitives
(Davidlohr Bueso)
- optimize various aspects of rwsems (Jason Low, Davidlohr Bueso,
Waiman Long)
- optimize smp_cond_load_acquire() on arm64 and implement LSE based
atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
on arm64 (Will Deacon)
- introduce smp_acquire__after_ctrl_dep() and fix various barrier
mis-uses and bugs (Peter Zijlstra)
- after discovering ancient spin_unlock_wait() barrier bugs in its
implementation and usage, strengthen its semantics and update/fix
usage sites (Peter Zijlstra)
- optimize mutex_trylock() fastpath (Peter Zijlstra)
- ... misc fixes and cleanups"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API
locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire()
locking/static_keys: Fix non static symbol Sparse warning
locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec()
locking/atomic, arch/tile: Fix tilepro build
locking/atomic, arch/m68k: Remove comment
locking/atomic, arch/arc: Fix build
locking/Documentation: Clarify limited control-dependency scope
locking/atomic, arch/rwsem: Employ atomic_long_fetch_add()
locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire()
locking/atomic, arch/mips: Convert to _relaxed atomics
locking/atomic, arch/alpha: Convert to _relaxed atomics
locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions
locking/atomic: Remove linux/atomic.h:atomic_fetch_or()
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
locking/atomic: Fix atomic64_relaxed() bits
locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
...
__GFP_REPEAT has a rather weak semantic but since it has been introduced
around 2.6.12 it has been ignored for low order allocations.
pte_alloc_one_kernel uses __get_order_pte but this is obviously always
zero because BITS_FOR_PTE is not larger than 9 yet the page size is
always larger than 4K. This means that this flag has never been
actually useful here because it has always been used only for
PAGE_ALLOC_COSTLY requests.
Link: http://lkml.kernel.org/r/1464599699-30131-7-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since all architectures have this implemented now natively, remove this
dead code.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Implement FETCH-OP atomic primitives, these are very similar to the
existing OP-RETURN primitives we already have, except they return the
value of the atomic variable _before_ modification.
This is especially useful for irreversible operations -- such as
bitops (because it becomes impossible to reconstruct the state prior
to modification).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch updates/fixes all spin_unlock_wait() implementations.
The update is in semantics; where it previously was only a control
dependency, we now upgrade to a full load-acquire to match the
store-release from the spin_unlock() we waited on. This ensures that
when spin_unlock_wait() returns, we're guaranteed to observe the full
critical section we waited on.
This fixes a number of spin_unlock_wait() users that (not
unreasonably) rely on this.
I also fixed a number of ticket lock versions to only wait on the
current lock holder, instead of for a full unlock, as this is
sufficient.
Furthermore; again for ticket locks; I added an smp_rmb() in between
the initial ticket load and the spin loop testing the current value
because I could not convince myself the address dependency is
sufficient, esp. if the loads are of different sizes.
I'm more than happy to remove this smp_rmb() again if people are
certain the address dependency does indeed work as expected.
Note: PPC32 will be fixed independently
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: chris@zankel.net
Cc: cmetcalf@mellanox.com
Cc: davem@davemloft.net
Cc: dhowells@redhat.com
Cc: james.hogan@imgtec.com
Cc: jejb@parisc-linux.org
Cc: linux@armlinux.org.uk
Cc: mpe@ellerman.id.au
Cc: ralf@linux-mips.org
Cc: realmz6@gmail.com
Cc: rkuo@codeaurora.org
Cc: rth@twiddle.net
Cc: schwidefsky@de.ibm.com
Cc: tony.luck@intel.com
Cc: vgupta@synopsys.com
Cc: ysato@users.sourceforge.jp
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This reverts commit e78fdfef84.
The issue was fixed in hardware in HS2.1C release and there are no known
external users of affected RTL so revert the whole delayed retry series !
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This reverts commit b89aa12c17.
The issue was fixed in hardware in HS2.1C release and there are no known
external users of affected RTL so revert the whole delayed retry series !
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This reverts commit 1097163870.
The issue was fixed in hardware in HS2.1C release and there are no known
external users of affected RTL - so revert thw whole delayed retry
series !
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
I have only one patch for asm-generic in this release, this one is from
James Hogan and updates the generic system call table for renameat2
so we don't need to provide both renameat and renameat2 in newly
added architectures.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=ae81
-----END PGP SIGNATURE-----
Merge tag 'asm-generic-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic cleanup from Arnd Bergmann:
"I have only one patch for asm-generic in this release, this one is
from James Hogan and updates the generic system call table for
renameat2 so we don't need to provide both renameat and renameat2 in
newly added architectures"
* tag 'asm-generic-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
asm-generic: Drop renameat syscall from default list
Merge updates from Andrew Morton:
- fsnotify fix
- poll() timeout fix
- a few scripts/ tweaks
- debugobjects updates
- the (small) ocfs2 queue
- Minor fixes to kernel/padata.c
- Maybe half of the MM queue
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (117 commits)
mm, page_alloc: restore the original nodemask if the fast path allocation failed
mm, page_alloc: uninline the bad page part of check_new_page()
mm, page_alloc: don't duplicate code in free_pcp_prepare
mm, page_alloc: defer debugging checks of pages allocated from the PCP
mm, page_alloc: defer debugging checks of freed pages until a PCP drain
cpuset: use static key better and convert to new API
mm, page_alloc: inline pageblock lookup in page free fast paths
mm, page_alloc: remove unnecessary variable from free_pcppages_bulk
mm, page_alloc: pull out side effects from free_pages_check
mm, page_alloc: un-inline the bad part of free_pages_check
mm, page_alloc: check multiple page fields with a single branch
mm, page_alloc: remove field from alloc_context
mm, page_alloc: avoid looking up the first zone in a zonelist twice
mm, page_alloc: shortcut watermark checks for order-0 pages
mm, page_alloc: reduce cost of fair zone allocation policy retry
mm, page_alloc: shorten the page allocator fast path
mm, page_alloc: check once if a zone has isolated pageblocks
mm, page_alloc: move __GFP_HARDWALL modifications out of the fastpath
mm, page_alloc: simplify last cpupid reset
mm, page_alloc: remove unnecessary initialisation from __alloc_pages_nodemask()
...
I've just discovered that the useful-sounding has_transparent_hugepage()
is actually an architecture-dependent minefield: on some arches it only
builds if CONFIG_TRANSPARENT_HUGEPAGE=y, on others it's also there when
not, but on some of those (arm and arm64) it then gives the wrong
answer; and on mips alone it's marked __init, which would crash if
called later (but so far it has not been called later).
Straighten this out: make it available to all configs, with a sensible
default in asm-generic/pgtable.h, removing its definitions from those
arches (arc, arm, arm64, sparc, tile) which are served by the default,
adding #define has_transparent_hugepage has_transparent_hugepage to
those (mips, powerpc, s390, x86) which need to override the default at
runtime, and removing the __init from mips (but maybe that kind of code
should be avoided after init: set a static variable the first time it's
called).
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc]
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [arch/s390]
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The default 256 bytes sometimes is just not enough.
We usually provide earlycon=... and console=... and ip=...
All this and more may need more room.
Signed-off-by: Noam Camus <noamc@ezchip.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Since the CTOP is SMT hardware multi-threaded, we need to hint
the HW that now will be a very good time to do a hardware
thread context switching. This is done by issuing the schd.rw
instruction (binary coded here so as to not require specific
revision of GCC to build the kernel).
sched.rw means that Thread becomes eligible for execution by
the threads scheduler after all pending read/write
transactions were completed.
Implementing cpu_relax_lowlatency() with barrier()
Since with current semantics of cpu_relax() it may take a
while till yielded CPU will get back.
Signed-off-by: Noam Camus <noamc@ezchip.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
