Implement functions watchdog_nmi_enable and watchdog_nmi_disable to
enable/disable nmi watchdog. Sparc uses arch specific nmi watchdog
handler. Currently, we do not have a way to enable/disable nmi watchdog
dynamically. With these patches we can enable or disable arch specific
nmi watchdogs using proc or sysctl interface.
Example commands.
To enable: echo 1 > /proc/sys/kernel/nmi_watchdog
To disable: echo 0 > /proc/sys/kernel/nmi_watchdog
It can also achieved using the sysctl parameter kernel.nmi_watchdog
Link: http://lkml.kernel.org/r/1478034826-43888-4-git-send-email-babu.moger@oracle.com
Signed-off-by: Babu Moger <babu.moger@oracle.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Josh Hunt <johunt@akamai.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This change allows us to pass DMA_ATTR_SKIP_CPU_SYNC which allows us to
avoid invoking cache line invalidation if the driver will just handle it
via a sync_for_cpu or sync_for_device call.
Link: http://lkml.kernel.org/r/20161110113544.76501.40008.stgit@ahduyck-blue-test.jf.intel.com
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull smp hotplug updates from Thomas Gleixner:
"This is the final round of converting the notifier mess to the state
machine. The removal of the notifiers and the related infrastructure
will happen around rc1, as there are conversions outstanding in other
trees.
The whole exercise removed about 2000 lines of code in total and in
course of the conversion several dozen bugs got fixed. The new
mechanism allows to test almost every hotplug step standalone, so
usage sites can exercise all transitions extensively.
There is more room for improvement, like integrating all the
pointlessly different architecture mechanisms of synchronizing,
setting cpus online etc into the core code"
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
tracing/rb: Init the CPU mask on allocation
soc/fsl/qbman: Convert to hotplug state machine
soc/fsl/qbman: Convert to hotplug state machine
zram: Convert to hotplug state machine
KVM/PPC/Book3S HV: Convert to hotplug state machine
arm64/cpuinfo: Convert to hotplug state machine
arm64/cpuinfo: Make hotplug notifier symmetric
mm/compaction: Convert to hotplug state machine
iommu/vt-d: Convert to hotplug state machine
mm/zswap: Convert pool to hotplug state machine
mm/zswap: Convert dst-mem to hotplug state machine
mm/zsmalloc: Convert to hotplug state machine
mm/vmstat: Convert to hotplug state machine
mm/vmstat: Avoid on each online CPU loops
mm/vmstat: Drop get_online_cpus() from init_cpu_node_state/vmstat_cpu_dead()
tracing/rb: Convert to hotplug state machine
oprofile/nmi timer: Convert to hotplug state machine
net/iucv: Use explicit clean up labels in iucv_init()
x86/pci/amd-bus: Convert to hotplug state machine
x86/oprofile/nmi: Convert to hotplug state machine
...
Pull locking updates from Ingo Molnar:
"The tree got pretty big in this development cycle, but the net effect
is pretty good:
115 files changed, 673 insertions(+), 1522 deletions(-)
The main changes were:
- Rework and generalize the mutex code to remove per arch mutex
primitives. (Peter Zijlstra)
- Add vCPU preemption support: add an interface to query the
preemption status of vCPUs and use it in locking primitives - this
optimizes paravirt performance. (Pan Xinhui, Juergen Gross,
Christian Borntraeger)
- Introduce cpu_relax_yield() and remov cpu_relax_lowlatency() to
clean up and improve the s390 lock yielding machinery and its core
kernel impact. (Christian Borntraeger)
- Micro-optimize mutexes some more. (Waiman Long)
- Reluctantly add the to-be-deprecated mutex_trylock_recursive()
interface on a temporary basis, to give the DRM code more time to
get rid of its locking hacks. Any other users will be NAK-ed on
sight. (We turned off the deprecation warning for the time being to
not pollute the build log.) (Peter Zijlstra)
- Improve the rtmutex code a bit, in light of recent long lived
bugs/races. (Thomas Gleixner)
- Misc fixes, cleanups"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
x86/paravirt: Fix bool return type for PVOP_CALL()
x86/paravirt: Fix native_patch()
locking/ww_mutex: Use relaxed atomics
locking/rtmutex: Explain locking rules for rt_mutex_proxy_unlock()/init_proxy_locked()
locking/rtmutex: Get rid of RT_MUTEX_OWNER_MASKALL
x86/paravirt: Optimize native pv_lock_ops.vcpu_is_preempted()
locking/mutex: Break out of expensive busy-loop on {mutex,rwsem}_spin_on_owner() when owner vCPU is preempted
locking/osq: Break out of spin-wait busy waiting loop for a preempted vCPU in osq_lock()
Documentation/virtual/kvm: Support the vCPU preemption check
x86/xen: Support the vCPU preemption check
x86/kvm: Support the vCPU preemption check
x86/kvm: Support the vCPU preemption check
kvm: Introduce kvm_write_guest_offset_cached()
locking/core, x86/paravirt: Implement vcpu_is_preempted(cpu) for KVM and Xen guests
locking/spinlocks, s390: Implement vcpu_is_preempted(cpu)
locking/core, powerpc: Implement vcpu_is_preempted(cpu)
sched/core: Introduce the vcpu_is_preempted(cpu) interface
sched/wake_q: Rename WAKE_Q to DEFINE_WAKE_Q
locking/core: Provide common cpu_relax_yield() definition
locking/mutex: Don't mark mutex_trylock_recursive() as deprecated, temporarily
...
Pull sparc updates from David Miller:
"Just a bunch of small cleanups and fixes here, and support for user
probes from Allen Pais"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc: fix a building error reported by kbuild
sparc64: fix typo in pgd_clear()
sparc64: restore irq in error paths in iommu
sparc: leon: Fix a retry loop in leon_init_timers()
sparc64: make string buffers large enough
sparc64: move dereference after check for NULL
sparc: kernel: use builtin_platform_driver
sparc64:Support User Probes for sparc
>> arch/sparc/include/asm/topology_64.h:44:44:
error: implicit declaration of function 'cpu_data'
[-Werror=implicit-function-declaration]
#define topology_physical_package_id(cpu) (cpu_data(cpu).proc_id)
^
Let's include cpudata.h in topology_64.h.
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
It really has to be pgdp, not pgd.
It just happend to work since all callers have 'pgd' as an argument.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are some error paths where we should restore IRQs but we don't.
Fixes: bb620c3d39 ("sparc: Make sparc64 use scalable lib/iommu-common.c functions")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The original code causes a static checker warning because it has a
continue inside a do { } while (0); loop. In that context, a continue
and a break are equivalent. The intent was to go back to the start of
the loop so the continue was a bug.
I've added a retry label at the start and changed the continue to a goto
retry. Then I removed the do { } while (0) loop and pulled the code in
one indent level.
Fixes: 2791c1a439 ("SPARC/LEON: added support for selecting Timer Core and Timer within core")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
My static checker complains that if "lvl" is ULONG_MAX (this is 64 bit)
then some of the strings will overflow. I don't know if that's possible
but it seems simple enough to make the buffers slightly larger.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We shouldn't dereference "iommu" until after we have checked that it is
non-NULL.
Fixes: f08978b0fd ("sparc64: Enable sun4v dma ops to use IOMMU v2 APIs")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use builtin_platform_driver() helper to simplify the code.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Eric Saint Etienne <eric.saint.etienne@oracle.com>
Signed-off-by: Allen Pais <allen.pais@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch exports the sender chronograph stats via the socket
SO_TIMESTAMPING channel. Currently we can instrument how long a
particular application unit of data was queued in TCP by tracking
SOF_TIMESTAMPING_TX_SOFTWARE and SOF_TIMESTAMPING_TX_SCHED. Having
these sender chronograph stats exported simultaneously along with
these timestamps allow further breaking down the various sender
limitation. For example, a video server can tell if a particular
chunk of video on a connection takes a long time to deliver because
TCP was experiencing small receive window. It is not possible to
tell before this patch without packet traces.
To prepare these stats, the user needs to set
SOF_TIMESTAMPING_OPT_STATS and SOF_TIMESTAMPING_OPT_TSONLY flags
while requesting other SOF_TIMESTAMPING TX timestamps. When the
timestamps are available in the error queue, the stats are returned
in a separate control message of type SCM_TIMESTAMPING_OPT_STATS,
in a list of TLVs (struct nlattr) of types: TCP_NLA_BUSY_TIME,
TCP_NLA_RWND_LIMITED, TCP_NLA_SNDBUF_LIMITED. Unit is microsecond.
Signed-off-by: Francis Yan <francisyyan@gmail.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.
The previous convention of keeping the files around until the CPU is dead
has not been preserved as there is no point to keep them available when the
cpu is going down. This makes the hotplug call symmetric.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Cc: rt@linuxtronix.de
Link: http://lkml.kernel.org/r/20161117183541.8588-18-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Drop duplicate header scatterlist.h from iommu_common.h.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This new config parameter limits the space used for "Lock debugging:
prove locking correctness" by about 4MB. The current sparc systems have
the limitation of 32MB size for kernel size including .text, .data and
.bss sections. With PROVE_LOCKING feature, the kernel size could grow
beyond this limit and causing system boot-up issues. With this option,
kernel limits the size of the entries of lock_chains, stack_trace etc.,
so that kernel fits in required size limit. This is not visible to user
and only used for sparc.
Signed-off-by: Babu Moger <babu.moger@oracle.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
ATU 64bit addressing allows PCIe devices with 64bit DMA capabilities
to use ATU for 64bit DMA.
Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Reviewed-by: chris hyser <chris.hyser@oracle.com>
Acked-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add Hypervisor IOMMU v2 APIs pci_iotsb_map(), pci_iotsb_demap() and
enable sun4v dma ops to use IOMMU v2 API for all PCIe devices with
64bit DMA mask.
Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Reviewed-by: chris hyser <chris.hyser@oracle.com>
Acked-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to use Hypervisor (HV) IOMMU v2 API for map/demap, each PCIe
device has to be bound to IOTSB using HV API pci_iotsb_bind().
Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Reviewed-by: chris hyser <chris.hyser@oracle.com>
Acked-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Like legacy IOMMU, use common iommu_map_table and iommu_pool for ATU.
This change initializes iommu_map_table and iommu_pool for ATU.
Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Reviewed-by: chris hyser <chris.hyser@oracle.com>
Reviewed-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ATU (Address Translation Unit) is a new IOMMU in SPARC supported with
Hypervisor IOMMU v2 APIs.
Current SPARC IOMMU supports only 32bit address ranges and one TSB
per PCIe root complex that has a 2GB per root complex DVMA space
limit. The limit has become a scalability bottleneck nowadays that
a typical 10G/40G NIC can consume 300MB-500MB DVMA space per
instance. When DVMA resource is exhausted, devices will not be usable
since the driver can't allocate DVMA.
ATU removes bottleneck by allowing guest os to create IOTSB of size
32G (or more) with 64bit address ranges available in ATU HW. 32G is
more than enough DVMA space to be shared by all PCIe devices under
root complex contrast to 2G space provided by legacy IOMMU.
ATU allows PCIe devices to use 64bit DMA addressing. Devices
which choose to use 32bit DMA mask will continue to work with the
existing legacy IOMMU.
Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Reviewed-by: chris hyser <chris.hyser@oracle.com>
Acked-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This change allows ATU (new IOMMU) in SPARC systems to request
large (32M) contiguous memory during boot for creating IOTSB backing
store.
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
No need to duplicate the same define everywhere. Since
the only user is stop-machine and the only provider is
s390, we can use a default implementation of cpu_relax_yield()
in sched.h.
Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
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: Will Deacon <will.deacon@arm.com>
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-s390 <linux-s390@vger.kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1479298985-191589-1-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As there are no users left, we can remove cpu_relax_lowlatency()
implementations from every architecture.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Cc: <linux-arch@vger.kernel.org>
Link: http://lkml.kernel.org/r/1477386195-32736-6-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
For spinning loops people do often use barrier() or cpu_relax().
For most architectures cpu_relax and barrier are the same, but on
some architectures cpu_relax can add some latency.
For example on power,sparc64 and arc, cpu_relax can shift the CPU
towards other hardware threads in an SMT environment.
On s390 cpu_relax does even more, it uses an hypercall to the
hypervisor to give up the timeslice.
In contrast to the SMT yielding this can result in larger latencies.
In some places this latency is unwanted, so another variant
"cpu_relax_lowlatency" was introduced. Before this is used in more
and more places, lets revert the logic and provide a cpu_relax_yield
that can be called in places where yielding is more important than
latency. By default this is the same as cpu_relax on all architectures.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1477386195-32736-2-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A compile warning is introduced by a commit to fix the find_node().
This patch fix the compile warning by moving find_node() into __init
section. Because find_node() is only used by memblock_nid_range() which
is only used by a __init add_node_ranges(). find_node() and
memblock_nid_range() should also be inside __init section.
Signed-off-by: Thomas Tai <thomas.tai@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When booting up LDOM, find_node() warns that a physical address
doesn't match a NUMA node.
WARNING: CPU: 0 PID: 0 at arch/sparc/mm/init_64.c:835
find_node+0xf4/0x120 find_node: A physical address doesn't
match a NUMA node rule. Some physical memory will be
owned by node 0.Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 4.9.0-rc3 #4
Call Trace:
[0000000000468ba0] __warn+0xc0/0xe0
[0000000000468c74] warn_slowpath_fmt+0x34/0x60
[00000000004592f4] find_node+0xf4/0x120
[0000000000dd0774] add_node_ranges+0x38/0xe4
[0000000000dd0b1c] numa_parse_mdesc+0x268/0x2e4
[0000000000dd0e9c] bootmem_init+0xb8/0x160
[0000000000dd174c] paging_init+0x808/0x8fc
[0000000000dcb0d0] setup_arch+0x2c8/0x2f0
[0000000000dc68a0] start_kernel+0x48/0x424
[0000000000dcb374] start_early_boot+0x27c/0x28c
[0000000000a32c08] tlb_fixup_done+0x4c/0x64
[0000000000027f08] 0x27f08
It is because linux use an internal structure node_masks[] to
keep the best memory latency node only. However, LDOM mdesc can
contain single latency-group with multiple memory latency nodes.
If the address doesn't match the best latency node within
node_masks[], it should check for an alternative via mdesc.
The warning message should only be printed if the address
doesn't match any node_masks[] nor within mdesc. To minimize
the impact of searching mdesc every time, the last matched
mask and index is stored in a variable.
Signed-off-by: Thomas Tai <thomas.tai@oracle.com>
Reviewed-by: Chris Hyser <chris.hyser@oracle.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the vmalloc area gets fragmented, and because the firmware
mapping area sits between where modules live and the vmalloc area, we
can sometimes receive requests for enormous kernel TLB range flushes.
When this happens the cpu just spins flushing billions of pages and
this triggers the NMI watchdog and other problems.
We took care of this on the TSB side by doing a linear scan of the
table once we pass a certain threshold.
Do something similar for the TLB flush, however we are limited by
the TLB flush facilities provided by the different chip variants.
First of all we use an (mostly arbitrary) cut-off of 256K which is
about 32 pages. This can be tuned in the future.
The huge range code path for each chip works as follows:
1) On spitfire we flush all non-locked TLB entries using diagnostic
acceses.
2) On cheetah we use the "flush all" TLB flush.
3) On sun4v/hypervisor we do a TLB context flush on context 0, which
unlike previous chips does not remove "permanent" or locked
entries.
We could probably do something better on spitfire, such as limiting
the flush to kernel TLB entries or even doing range comparisons.
However that probably isn't worth it since those chips are old and
the TLB only had 64 entries.
Reported-by: James Clarke <jrtc27@jrtc27.com>
Tested-by: James Clarke <jrtc27@jrtc27.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Just like the non-cross-call TLB flush handlers, the cross-call ones need
to avoid doing PC-relative branches outside of their code blocks.
Signed-off-by: David S. Miller <davem@davemloft.net>
If the number of pages we are flushing is more than twice the number
of entries in the TSB, just scan the TSB table for matches rather
than probing each and every page in the range.
Based upon a patch and report by James Clarke.
Signed-off-by: David S. Miller <davem@davemloft.net>
Additionally, if the offset will overflow the immediate for a ba,pt
instruction, fall back on a standard ba to get an extra 3 bits.
Signed-off-by: James Clarke <jrtc27@jrtc27.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we copy code over to patch another piece of code, we can only use
PC-relative branches that target code within that piece of code.
Such PC-relative branches cannot be made to external symbols because
the patch moves the location of the code and thus modifies the
relative address of external symbols.
Use an absolute jmpl to fix this problem.
Signed-off-by: David S. Miller <davem@davemloft.net>
Its all generic atomic_long_t stuff now.
Tested-by: Jason Low <jason.low2@hpe.com>
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>
Now that all of the user copy routines are converted to return
accurate residual lengths when an exception occurs, we no longer need
the broken fixup routines.
Signed-off-by: David S. Miller <davem@davemloft.net>
Report the exact number of bytes which have not been successfully
copied when an exception occurs, using the running remaining length.
Signed-off-by: David S. Miller <davem@davemloft.net>
Report the exact number of bytes which have not been successfully
copied when an exception occurs, using the running remaining length.
Signed-off-by: David S. Miller <davem@davemloft.net>
Report the exact number of bytes which have not been successfully
copied when an exception occurs, using the running remaining length.
Signed-off-by: David S. Miller <davem@davemloft.net>
Report the exact number of bytes which have not been successfully
copied when an exception occurs, using the running remaining length.
Signed-off-by: David S. Miller <davem@davemloft.net>
Report the exact number of bytes which have not been successfully
copied when an exception occurs, using the running remaining length.
Signed-off-by: David S. Miller <davem@davemloft.net>
Report the exact number of bytes which have not been successfully
copied when an exception occurs, using the running remaining length.
Signed-off-by: David S. Miller <davem@davemloft.net>
Report the exact number of bytes which have not been successfully
copied when an exception occurs, using the running remaining length.
Signed-off-by: David S. Miller <davem@davemloft.net>
The fixup helper function mechanism for handling user copy fault
handling is not %100 accurrate, and can never be made so.
We are going to transition the code to return the running return
return length, which is always kept track in one or more registers
of each of these routines.
In order to convert them one by one, we have to allow the existing
behavior to continue functioning.
Therefore make all the copy code that wants the fixup helper to be
used return negative one.
After all of the user copy routines have been converted, this logic
and the fixup helpers themselves can be removed completely.
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix [-Wold-style-declaration] GCC warnings by moving the inline keyword
before the return type.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
