This patch removes the NUMA PTE bits and associated helpers. As a
side-effect it increases the maximum possible swap space on x86-64.
One potential source of problems is races between the marking of PTEs
PROT_NONE, NUMA hinting faults and migration. It must be guaranteed that
a PTE being protected is not faulted in parallel, seen as a pte_none and
corrupting memory. The base case is safe but transhuge has problems in
the past due to an different migration mechanism and a dependance on page
lock to serialise migrations and warrants a closer look.
task_work hinting update parallel fault
------------------------ --------------
change_pmd_range
change_huge_pmd
__pmd_trans_huge_lock
pmdp_get_and_clear
__handle_mm_fault
pmd_none
do_huge_pmd_anonymous_page
read? pmd_lock blocks until hinting complete, fail !pmd_none test
write? __do_huge_pmd_anonymous_page acquires pmd_lock, checks pmd_none
pmd_modify
set_pmd_at
task_work hinting update parallel migration
------------------------ ------------------
change_pmd_range
change_huge_pmd
__pmd_trans_huge_lock
pmdp_get_and_clear
__handle_mm_fault
do_huge_pmd_numa_page
migrate_misplaced_transhuge_page
pmd_lock waits for updates to complete, recheck pmd_same
pmd_modify
set_pmd_at
Both of those are safe and the case where a transhuge page is inserted
during a protection update is unchanged. The case where two processes try
migrating at the same time is unchanged by this series so should still be
ok. I could not find a case where we are accidentally depending on the
PTE not being cleared and flushed. If one is missed, it'll manifest as
corruption problems that start triggering shortly after this series is
merged and only happen when NUMA balancing is enabled.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ppc64 should not be depending on DSISR_PROTFAULT and it's unexpected if
they are triggered. This patch adds warnings just in case they are being
accidentally depended upon.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert existing users of pte_numa and friends to the new helper. Note
that the kernel is broken after this patch is applied until the other page
table modifiers are also altered. This patch layout is to make review
easier.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull block driver changes from Jens Axboe:
"This contains:
- The 4k/partition fixes for brd from Boaz/Matthew.
- A few xen front/back block fixes from David Vrabel and Roger Pau
Monne.
- Floppy changes from Takashi, cleaning the device file creation.
- Switching libata to use the new blk-mq tagging policy, removing
code (and a suboptimal implementation) from libata. This will
throw you a merge conflict, since a bug in the original libata
tagging code was fixed since this code was branched. Trivial.
From Shaohua.
- Conversion of loop to blk-mq, from Ming Lei.
- Cleanup of the io_schedule() handling in bsg from Peter Zijlstra.
He claims it improves on unreadable code, which will cost him a
beer.
- Maintainer update or NDB, now handled by Markus Pargmann.
- NVMe:
- Optimization from me that avoids a kmalloc/kfree per IO for
smaller (<= 8KB) IO. This cuts about 1% of high IOPS CPU
overhead.
- Removal of (now) dead RCU code, a relic from before NVMe was
converted to blk-mq"
* 'for-3.20/drivers' of git://git.kernel.dk/linux-block:
xen-blkback: default to X86_32 ABI on x86
xen-blkfront: fix accounting of reqs when migrating
xen-blkback,xen-blkfront: add myself as maintainer
block: Simplify bsg complete all
floppy: Avoid manual call of device_create_file()
NVMe: avoid kmalloc/kfree for smaller IO
MAINTAINERS: Update NBD maintainer
libata: make sata_sil24 use fifo tag allocator
libata: move sas ata tag allocation to libata-scsi.c
libata: use blk taging
NVMe: within nvme_free_queues(), delete RCU sychro/deferred free
null_blk: suppress invalid partition info
brd: Request from fdisk 4k alignment
brd: Fix all partitions BUGs
axonram: Fix bug in direct_access
loop: add blk-mq.h include
block: loop: don't handle REQ_FUA explicitly
block: loop: introduce lo_discard() and lo_req_flush()
block: loop: say goodby to bio
block: loop: improve performance via blk-mq
Pull core block IO changes from Jens Axboe:
"This contains:
- A series from Christoph that cleans up and refactors various parts
of the REQ_BLOCK_PC handling. Contributions in that series from
Dongsu Park and Kent Overstreet as well.
- CFQ:
- A bug fix for cfq for realtime IO scheduling from Jeff Moyer.
- A stable patch fixing a potential crash in CFQ in OOM
situations. From Konstantin Khlebnikov.
- blk-mq:
- Add support for tag allocation policies, from Shaohua. This is
a prep patch enabling libata (and other SCSI parts) to use the
blk-mq tagging, instead of rolling their own.
- Various little tweaks from Keith and Mike, in preparation for
DM blk-mq support.
- Minor little fixes or tweaks from me.
- A double free error fix from Tony Battersby.
- The partition 4k issue fixes from Matthew and Boaz.
- Add support for zero+unprovision for blkdev_issue_zeroout() from
Martin"
* 'for-3.20/core' of git://git.kernel.dk/linux-block: (27 commits)
block: remove unused function blk_bio_map_sg
block: handle the null_mapped flag correctly in blk_rq_map_user_iov
blk-mq: fix double-free in error path
block: prevent request-to-request merging with gaps if not allowed
blk-mq: make blk_mq_run_queues() static
dm: fix multipath regression due to initializing wrong request
cfq-iosched: handle failure of cfq group allocation
block: Quiesce zeroout wrapper
block: rewrite and split __bio_copy_iov()
block: merge __bio_map_user_iov into bio_map_user_iov
block: merge __bio_map_kern into bio_map_kern
block: pass iov_iter to the BLOCK_PC mapping functions
block: add a helper to free bio bounce buffer pages
block: use blk_rq_map_user_iov to implement blk_rq_map_user
block: simplify bio_map_kern
block: mark blk-mq devices as stackable
block: keep established cmd_flags when cloning into a blk-mq request
block: add blk-mq support to blk_insert_cloned_request()
block: require blk_rq_prep_clone() be given an initialized clone request
blk-mq: add tag allocation policy
...
This time with:
* Generic page-table framework for ARM IOMMUs using the LPAE page-table
format, ARM-SMMU and Renesas IPMMU make use of it already.
* Break out of the IO virtual address allocator from the Intel IOMMU so
that it can be used by other DMA-API implementations too. The first
user will be the ARM64 common DMA-API implementation for IOMMUs
* Device tree support for Renesas IPMMU
* Various fixes and cleanups all over the place
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Merge tag 'iommu-updates-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:
"This time with:
- Generic page-table framework for ARM IOMMUs using the LPAE
page-table format, ARM-SMMU and Renesas IPMMU make use of it
already.
- Break out the IO virtual address allocator from the Intel IOMMU so
that it can be used by other DMA-API implementations too. The
first user will be the ARM64 common DMA-API implementation for
IOMMUs
- Device tree support for Renesas IPMMU
- Various fixes and cleanups all over the place"
* tag 'iommu-updates-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (36 commits)
iommu/amd: Convert non-returned local variable to boolean when relevant
iommu: Update my email address
iommu/amd: Use wait_event in put_pasid_state_wait
iommu/amd: Fix amd_iommu_free_device()
iommu/arm-smmu: Avoid build warning
iommu/fsl: Various cleanups
iommu/fsl: Use %pa to print phys_addr_t
iommu/omap: Print phys_addr_t using %pa
iommu: Make more drivers depend on COMPILE_TEST
iommu/ipmmu-vmsa: Fix IOMMU lookup when multiple IOMMUs are registered
iommu: Disable on !MMU builds
iommu/fsl: Remove unused fsl_of_pamu_ids[]
iommu/fsl: Fix section mismatch
iommu/ipmmu-vmsa: Use the ARM LPAE page table allocator
iommu: Fix trace_map() to report original iova and original size
iommu/arm-smmu: add support for iova_to_phys through ATS1PR
iopoll: Introduce memory-mapped IO polling macros
iommu/arm-smmu: don't touch the secure STLBIALL register
iommu/arm-smmu: make use of generic LPAE allocator
iommu: io-pgtable-arm: add non-secure quirk
...
Merge second set of updates from Andrew Morton:
"More of MM"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (83 commits)
mm/nommu.c: fix arithmetic overflow in __vm_enough_memory()
mm/mmap.c: fix arithmetic overflow in __vm_enough_memory()
vmstat: Reduce time interval to stat update on idle cpu
mm/page_owner.c: remove unnecessary stack_trace field
Documentation/filesystems/proc.txt: describe /proc/<pid>/map_files
mm: incorporate read-only pages into transparent huge pages
vmstat: do not use deferrable delayed work for vmstat_update
mm: more aggressive page stealing for UNMOVABLE allocations
mm: always steal split buddies in fallback allocations
mm: when stealing freepages, also take pages created by splitting buddy page
mincore: apply page table walker on do_mincore()
mm: /proc/pid/clear_refs: avoid split_huge_page()
mm: pagewalk: fix misbehavior of walk_page_range for vma(VM_PFNMAP)
mempolicy: apply page table walker on queue_pages_range()
arch/powerpc/mm/subpage-prot.c: use walk->vma and walk_page_vma()
memcg: cleanup preparation for page table walk
numa_maps: remove numa_maps->vma
numa_maps: fix typo in gather_hugetbl_stats
pagemap: use walk->vma instead of calling find_vma()
clear_refs: remove clear_refs_private->vma and introduce clear_refs_test_walk()
...
Including:
- Update of all defconfigs
- Addition of a bunch of config options to modernise our defconfigs
- Some PS3 updates from Geoff
- Optimised memcmp for 64 bit from Anton
- Fix for kprobes that allows 'perf probe' to work from Naveen
- Several cxl updates from Ian & Ryan
- Expanded support for the '24x7' PMU from Cody & Sukadev
- Freescale updates from Scott:
"Highlights include 8xx optimizations, some more work on datapath device
tree content, e300 machine check support, t1040 corenet error reporting,
and various cleanups and fixes."
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Merge tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull powerpc updates from Michael Ellerman:
- Update of all defconfigs
- Addition of a bunch of config options to modernise our defconfigs
- Some PS3 updates from Geoff
- Optimised memcmp for 64 bit from Anton
- Fix for kprobes that allows 'perf probe' to work from Naveen
- Several cxl updates from Ian & Ryan
- Expanded support for the '24x7' PMU from Cody & Sukadev
- Freescale updates from Scott:
"Highlights include 8xx optimizations, some more work on datapath
device tree content, e300 machine check support, t1040 corenet
error reporting, and various cleanups and fixes"
* tag 'powerpc-3.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (102 commits)
cxl: Add missing return statement after handling AFU errror
cxl: Fail AFU initialisation if an invalid configuration record is found
cxl: Export optional AFU configuration record in sysfs
powerpc/mm: Warn on flushing tlb page in kernel context
powerpc/powernv: Add OPAL soft-poweroff routine
powerpc/perf/hv-24x7: Document sysfs event description entries
powerpc/perf/hv-gpci: add the remaining gpci requests
powerpc/perf/{hv-gpci, hv-common}: generate requests with counters annotated
powerpc/perf/hv-24x7: parse catalog and populate sysfs with events
perf: define EVENT_DEFINE_RANGE_FORMAT_LITE helper
perf: add PMU_EVENT_ATTR_STRING() helper
perf: provide sysfs_show for struct perf_pmu_events_attr
powerpc/kernel: Avoid initializing device-tree pointer twice
powerpc: Remove old compile time disabled syscall tracing code
powerpc/kernel: Make syscall_exit a local label
cxl: Fix device_node reference counting
powerpc/mm: bail out early when flushing TLB page
powerpc: defconfigs: add MTD_SPI_NOR (new dependency for M25P80)
perf/powerpc: reset event hw state when adding it to the PMU
powerpc/qe: Use strlcpy()
...
We don't have to use mm_walk->private to pass vma to the callback function
because of mm_walk->vma. And walk_page_vma() is useful if we walk over a
single vma.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
LKP has triggered a compiler warning after my recent patch "mm: account
pmd page tables to the process":
mm/mmap.c: In function 'exit_mmap':
>> mm/mmap.c:2857:2: warning: right shift count >= width of type [enabled by default]
The code:
> 2857 WARN_ON(mm_nr_pmds(mm) >
2858 round_up(FIRST_USER_ADDRESS, PUD_SIZE) >> PUD_SHIFT);
In this, on tile, we have FIRST_USER_ADDRESS defined as 0. round_up() has
the same type -- int. PUD_SHIFT.
I think the best way to fix it is to define FIRST_USER_ADDRESS as unsigned
long. On every arch for consistency.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently we have many duplicates in definitions around
follow_huge_addr(), follow_huge_pmd(), and follow_huge_pud(), so this
patch tries to remove the m. The basic idea is to put the default
implementation for these functions in mm/hugetlb.c as weak symbols
(regardless of CONFIG_ARCH_WANT_GENERAL_HUGETL B), and to implement
arch-specific code only when the arch needs it.
For follow_huge_addr(), only powerpc and ia64 have their own
implementation, and in all other architectures this function just returns
ERR_PTR(-EINVAL). So this patch sets returning ERR_PTR(-EINVAL) as
default.
As for follow_huge_(pmd|pud)(), if (pmd|pud)_huge() is implemented to
always return 0 in your architecture (like in ia64 or sparc,) it's never
called (the callsite is optimized away) no matter how implemented it is.
So in such architectures, we don't need arch-specific implementation.
In some architecture (like mips, s390 and tile,) their current
arch-specific follow_huge_(pmd|pud)() are effectively identical with the
common code, so this patch lets these architecture use the common code.
One exception is metag, where pmd_huge() could return non-zero but it
expects follow_huge_pmd() to always return NULL. This means that we need
arch-specific implementation which returns NULL. This behavior looks
strange to me (because non-zero pmd_huge() implies that the architecture
supports PMD-based hugepage, so follow_huge_pmd() can/should return some
relevant value,) but that's beyond this cleanup patch, so let's keep it.
Justification of non-trivial changes:
- in s390, follow_huge_pmd() checks !MACHINE_HAS_HPAGE at first, and this
patch removes the check. This is OK because we can assume MACHINE_HAS_HPAGE
is true when follow_huge_pmd() can be called (note that pmd_huge() has
the same check and always returns 0 for !MACHINE_HAS_HPAGE.)
- in s390 and mips, we use HPAGE_MASK instead of PMD_MASK as done in common
code. This patch forces these archs use PMD_MASK, but it's OK because
they are identical in both archs.
In s390, both of HPAGE_SHIFT and PMD_SHIFT are 20.
In mips, HPAGE_SHIFT is defined as (PAGE_SHIFT + PAGE_SHIFT - 3) and
PMD_SHIFT is define as (PAGE_SHIFT + PAGE_SHIFT + PTE_ORDER - 3), but
PTE_ORDER is always 0, so these are identical.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull RCU updates from Ingo Molnar:
"The main RCU changes in this cycle are:
- Documentation updates.
- Miscellaneous fixes.
- Preemptible-RCU fixes, including fixing an old bug in the
interaction of RCU priority boosting and CPU hotplug.
- SRCU updates.
- RCU CPU stall-warning updates.
- RCU torture-test updates"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
rcu: Initialize tiny RCU stall-warning timeouts at boot
rcu: Fix RCU CPU stall detection in tiny implementation
rcu: Add GP-kthread-starvation checks to CPU stall warnings
rcu: Make cond_resched_rcu_qs() apply to normal RCU flavors
rcu: Optionally run grace-period kthreads at real-time priority
ksoftirqd: Use new cond_resched_rcu_qs() function
ksoftirqd: Enable IRQs and call cond_resched() before poking RCU
rcutorture: Add more diagnostics in rcu_barrier() test failure case
torture: Flag console.log file to prevent holdovers from earlier runs
torture: Add "-enable-kvm -soundhw pcspk" to qemu command line
rcutorture: Handle different mpstat versions
rcutorture: Check from beginning to end of grace period
rcu: Remove redundant rcu_batches_completed() declaration
rcutorture: Drop rcu_torture_completed() and friends
rcu: Provide rcu_batches_completed_sched() for TINY_RCU
rcutorture: Use unsigned for Reader Batch computations
rcutorture: Make build-output parsing correctly flag RCU's warnings
rcu: Make _batches_completed() functions return unsigned long
rcutorture: Issue warnings on close calls due to Reader Batch blows
documentation: Fix smp typo in memory-barriers.txt
...
This patch introduces a new module parameter for the KVM module; when it
is present, KVM attempts a bit of polling on every HLT before scheduling
itself out via kvm_vcpu_block.
This parameter helps a lot for latency-bound workloads---in particular
I tested it with O_DSYNC writes with a battery-backed disk in the host.
In this case, writes are fast (because the data doesn't have to go all
the way to the platters) but they cannot be merged by either the host or
the guest. KVM's performance here is usually around 30% of bare metal,
or 50% if you use cache=directsync or cache=writethrough (these
parameters avoid that the guest sends pointless flush requests, and
at the same time they are not slow because of the battery-backed cache).
The bad performance happens because on every halt the host CPU decides
to halt itself too. When the interrupt comes, the vCPU thread is then
migrated to a new physical CPU, and in general the latency is horrible
because the vCPU thread has to be scheduled back in.
With this patch performance reaches 60-65% of bare metal and, more
important, 99% of what you get if you use idle=poll in the guest. This
means that the tunable gets rid of this particular bottleneck, and more
work can be done to improve performance in the kernel or QEMU.
Of course there is some price to pay; every time an otherwise idle vCPUs
is interrupted by an interrupt, it will poll unnecessarily and thus
impose a little load on the host. The above results were obtained with
a mostly random value of the parameter (500000), and the load was around
1.5-2.5% CPU usage on one of the host's core for each idle guest vCPU.
The patch also adds a new stat, /sys/kernel/debug/kvm/halt_successful_poll,
that can be used to tune the parameter. It counts how many HLT
instructions received an interrupt during the polling period; each
successful poll avoids that Linux schedules the VCPU thread out and back
in, and may also avoid a likely trip to C1 and back for the physical CPU.
While the VM is idle, a Linux 4 VCPU VM halts around 10 times per second.
Of these halts, almost all are failed polls. During the benchmark,
instead, basically all halts end within the polling period, except a more
or less constant stream of 50 per second coming from vCPUs that are not
running the benchmark. The wasted time is thus very low. Things may
be slightly different for Windows VMs, which have a ~10 ms timer tick.
The effect is also visible on Marcelo's recently-introduced latency
test for the TSC deadline timer. Though of course a non-RT kernel has
awful latency bounds, the latency of the timer is around 8000-10000 clock
cycles compared to 20000-120000 without setting halt_poll_ns. For the TSC
deadline timer, thus, the effect is both a smaller average latency and
a smaller variance.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Kim Phillips reported following build failure.
LD init/built-in.o
mm/built-in.o: In function `free_pages_prepare':
mm/page_alloc.c:770: undefined reference to `.kernel_map_pages'
mm/built-in.o: In function `prep_new_page':
mm/page_alloc.c:933: undefined reference to `.kernel_map_pages'
mm/built-in.o: In function `map_pages':
mm/compaction.c:61: undefined reference to `.kernel_map_pages'
make: *** [vmlinux] Error 1
Reason for this problem is that commit 031bc5743f
("mm/debug-pagealloc: make debug-pagealloc boottime configurable")
forgot to remove the old declaration of kernel_map_pages() for some
architectures. This patch removes them to fix build failure.
Reported-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: David Miller <davem@davemloft.net>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Function __flush_tlb_page() must only be called for user contexts, so
put in extra hardening to warn on calling it for kernel context.
Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Register a notifier for a OPAL message indicating that the machine
should prepare itself for a graceful power off.
OPAL will tell us if the power off is a reboot or shutdown, but for now
we perform the same orderly_poweroff action.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Freescale updates from Scott:
"Highlights include 8xx optimizations, some more work on datapath device
tree content, e300 machine check support, t1040 corenet error reporting,
and various cleanups and fixes."
Currently a PAMU driver patch is very likely to receive some
checkpatch complaints about the code in the context of the
patch. This patch is an attempt to fix most of that and make
the driver more readable
Also fixed a subset of the sparse and coccinelle reported
issues.
Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Add the remaining gpci requests that contain counters suitable for use
by perf. Omit those that don't contain any counters (but note their
ommision).
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds (in req-gen/) a framework for defining gpci counter requests.
It uses macro magic similar to ftrace.
Also convert the existing hv-gpci request structures and enum values to
use the new framework (and adjust old users of the structs and enum
values to cope with changes in naming).
In exchange for this macro disaster, we get autogenerated event listing
for GPCI in sysfs, build time field offset checking, and zero
duplication of information about GPCI requests.
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Retrieves and parses the 24x7 catalog on POWER systems that supply it
(right now, only POWER 8). Events are exposed via sysfs in the standard
fashion, and are all parameterized.
$ cd /sys/bus/event_source/devices/hv_24x7/events
$ cat HPM_CS_FROM_L4_LDATA__PHYS_CORE
domain=0x2,offset=0xd58,core=?,lpar=0x0
$ cat HPM_TLBIE__VCPU_HOME_CHIP
domain=0x4,offset=0x358,vcpu=?,lpar=?
where user is required to specify values for the fields with '?' (like
core, vcpu, lpar above), when specifying the event with the perf tool.
Catalog is (at the moment) only parsed on boot. It needs re-parsing
when a some hypervisor events occur. At that point we'll also need to
prevent old events from continuing to function (counter that is passed
in via spare space in the config values?).
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Define a lite version of the EVENT_DEFINE_RANGE_FORMAT() that avoids
defining helper functions for the bit-field ranges.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
As commit 50ba08f3 ("of/fdt: Don't clear initial_boot_params
if fdt_check_header() fails") does, the device-tree pointer
"initial_boot_params" is initialized by early_init_dt_verify(),
which is called by early_init_devtree(). So we needn't explicitly
initialize that again in early_init_devtree().
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We have code to do syscall tracing which is disabled at compile time by
default. It's not been touched since the dawn of time (ie. v2.6.12).
There are now better ways to do syscall tracing, ie. using the
raw_syscall, or syscall tracepoints.
For the specific case of tracing syscalls at boot on a system that
doesn't get to userspace, you can boot with:
trace_event=syscalls tp_printk=on
Which will trace syscalls from boot, and echo all output to the console.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently when we back trace something that is in a syscall we see
something like this:
[c000000000000000] [c000000000000000] SyS_read+0x6c/0x110
[c000000000000000] [c000000000000000] syscall_exit+0x0/0x98
Although it's entirely correct, seeing syscall_exit at the bottom can be
confusing - we were exiting from a syscall and then called SyS_read() ?
If we instead change syscall_exit to be a local label we get something
more intuitive:
[c0000001fa46fde0] [c00000000026719c] SyS_read+0x6c/0x110
[c0000001fa46fe30] [c000000000009264] system_call+0x38/0xd0
ie. we were handling a system call, and it was SyS_read().
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When unbinding and rebinding the driver on a system with a card in PHB0, this
error condition is reached after a few attempts:
ERROR: Bad of_node_put() on /pciex@3fffe40000000
CPU: 0 PID: 3040 Comm: bash Not tainted 3.18.0-rc3-12545-g3627ffe #152
Call Trace:
[c000000721acb5c0] [c00000000086ef94] .dump_stack+0x84/0xb0 (unreliable)
[c000000721acb640] [c00000000073a0a8] .of_node_release+0xd8/0xe0
[c000000721acb6d0] [c00000000044bc44] .kobject_release+0x74/0xe0
[c000000721acb760] [c0000000007394fc] .of_node_put+0x1c/0x30
[c000000721acb7d0] [c000000000545cd8] .cxl_probe+0x1a98/0x1d50
[c000000721acb900] [c0000000004845a0] .local_pci_probe+0x40/0xc0
[c000000721acb980] [c000000000484998] .pci_device_probe+0x128/0x170
[c000000721acba30] [c00000000052400c] .driver_probe_device+0xac/0x2a0
[c000000721acbad0] [c000000000522468] .bind_store+0x108/0x160
[c000000721acbb70] [c000000000521448] .drv_attr_store+0x38/0x60
[c000000721acbbe0] [c000000000293840] .sysfs_kf_write+0x60/0xa0
[c000000721acbc50] [c000000000292500] .kernfs_fop_write+0x140/0x1d0
[c000000721acbcf0] [c000000000208648] .vfs_write+0xd8/0x260
[c000000721acbd90] [c000000000208b18] .SyS_write+0x58/0x100
[c000000721acbe30] [c000000000009258] syscall_exit+0x0/0x98
We are missing a call to of_node_get(). pnv_pci_to_phb_node() should
call of_node_get() otherwise np's reference count isn't incremented and
it might go away. Rename pnv_pci_to_phb_node() to pnv_pci_get_phb_node()
so it's clear it calls of_node_get().
Signed-off-by: Ryan Grimm <grimm@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
MMU_NO_CONTEXT is conditionally defined as 0 or (unsigned int)-1. However,
in __flush_tlb_page() a corresponding variable is only tested for open
coded 0, which can cause NULL pointer dereference if `mm' argument was
legitimately passed as such.
Bail out early in case the first argument is NULL, thus eliminate confusion
between different values of MMU_NO_CONTEXT and avoid disabling and then
re-enabling preemption unnecessarily.
Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Convert the powermac PCI driver to use the generic config access functions.
This changes accesses from (in|out)_(8|le16|le32) to readX/writeX variants.
I believe these should be equivalent for PCI config space accesses, but
confirmation would be nice.
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Michael Ellerman <mpe@ellerman.id.au>
CC: linuxppc-dev@lists.ozlabs.org
Convert the fsl_pci driver to use the generic config access functions.
This changes accesses from (in|out)_(8|le16|le32) to readX/writeX variants.
I believe these should be equivalent for PCI config space accesses, but
confirmation would be nice.
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Michael Ellerman <mpe@ellerman.id.au>
CC: linuxppc-dev@lists.ozlabs.org
These defconfigs contain the CONFIG_M25P80 symbol, which is now
dependent on the MTD_SPI_NOR symbol. Add CONFIG_MTD_SPI_NOR to satisfy
the new dependency.
At the same time, drop the now-nonexistent CONFIG_MTD_CHAR symbol.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Scott Wood <scottwood@freescale.com>
When adding an event to the PMU with PERF_EF_START the STOPPED and UPTODATE
flags need to be cleared in the hw.event status variable because they are
preventing the update of the event count on overflow interrupt.
Signed-off-by: Alexandru-Cezar Sardan <alexandru.sardan@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Replace strcpy and strncpy with strlcpy to avoid strings that are too
big, or lack null termination.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
[scottwood@freescale.com: cleaned up commit message]
Signed-off-by: Scott Wood <scottwood@freescale.com>
The of_node_put() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Fix the GPIO address in the device tree to match the documented location.
Signed-off-by: Alessio Igor Bogani <alessio.bogani@elettra.eu>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Change-Id: I16e63db731e55a3d60d4e147573c1af8718082d3
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Geoff Thorpe <Geoff.Thorpe@freescale.com>
Signed-off-by: Hai-Ying Wang <Haiying.Wang@freescale.com>
[Emil Medve: Sync with the upstream binding]
Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Geoff Thorpe <Geoff.Thorpe@freescale.com>
Signed-off-by: Hai-Ying Wang <Haiying.Wang@freescale.com>
[Emil Medve: Sync with the upstream binding]
Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Add support for the Artesyn MVME2500 Single Board Computer.
The MVME2500 is a 6U form factor VME64 computer with:
- A single Freescale QorIQ P2010 CPU
- 1 GB of DDR3 onboard memory
- Three Gigabit Ethernets
- Five 16550 compatible UARTS
- One USB 2.0 port, one SHDC socket and one SATA connector
- One PCI/PCI eXpress Mezzanine Card (PMC/XMC) Slot
- MultiProcessor Interrupt Controller (MPIC)
- A DS1375T Real Time Clock (RTC) and 512 KB of Non-Volatile Memory
- Two 64 KB EEPROMs
- U-Boot in 16 SPI Flash
This patch is based on linux-3.18 and has been boot tested.
Signed-off-by: Alessio Igor Bogani <alessio.bogani@elettra.eu>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Commit 746c9e9f92 "of/base: Fix PowerPC address parsing hack" limited
the applicability of the workaround whereby a missing ranges is treated
as an empty ranges. This workaround was hiding a bug in the etsec2
device tree nodes, which have children with reg, but did not have
ranges.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Reported-by: Alexander Graf <agraf@suse.de>
All accessed to PGD entries are done via 0(r11).
By using lower part of swapper_pg_dir as load index to r11, we can remove the
ori instruction.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
L1 base address is now aligned so we can insert L1 index into r11 directly and
then preserve r10
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
When pages are not 4K, PGDIR table is allocated with kmalloc(). In order to
optimise TLB handlers, aligned memory is needed. kmalloc() doesn't provide
aligned memory blocks, so lets use a kmem_cache pool instead.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Kernel MMU handling code handles validity of entries via _PMD_PRESENT which
corresponds to V bit in MD_TWC and MI_TWC. When the V bit is not set, MPC8xx
triggers TLBError exception. So we don't have to check that and branch ourself
to TLBError. We can set TLB entries with non present entries, remove all those
tests and let the 8xx handle it. This reduce the number of cycle when the
entries are valid which is the case most of the time, and doesn't significantly
increase the time for handling invalid entries.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Since commit 33fb845a6f ("powerpc/8xx: Don't use MD_TWC for walk"), MD_EPN and
MD_TWC are not writen anymore in FixupDAR so saving r3 has become useless.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>
