02 Jan, 2017
1 commit
-
The build robot reports:
.tmp_kallsyms1.o: In function `kallsyms_relative_base':
>> (.rodata+0x8a18): undefined reference to `_text'This is when using 'make alldefconfig'. Adding this _text symbol to mark
the start of the kernel as in other architecture fixes this.Signed-off-by: Stafford Horne
Acked-by: Jonas Bonn
25 Dec, 2016
2 commits
-
There is no point in having an extra type for extra confusion. u64 is
unambiguous.Conversion was done with the following coccinelle script:
@rem@
@@
-typedef u64 cycle_t;@fix@
typedef cycle_t;
@@
-cycle_t
+u64Signed-off-by: Thomas Gleixner
Cc: Peter Zijlstra
Cc: John Stultz -
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
sed -i -e "s!$PATT!#include !" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)to do the replacement at the end of the merge window.
Requested-by: Al Viro
Signed-off-by: Linus Torvalds
15 Dec, 2016
1 commit
-
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/20161110113524.76501.87966.stgit@ahduyck-blue-test.jf.intel.com
Signed-off-by: Alexander Duyck
Cc: Jonas Bonn
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
13 Dec, 2016
1 commit
-
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
...
12 Dec, 2016
9 commits
-
During page fault handling we check the last instruction to understand
if the fault was for a read or for a write. By default we fall back to
read. New instructions were added to the openrisc 1.1 spec for an
atomic load/store pair (l.lwa/l.swa).This patch adds the opcode for l.swa (0x33) allowing it to be treated as
a write operation.Signed-off-by: Stefan Kristiansson
[shorne@gmail.com: expanded a bit on the comment]
Signed-off-by: Stafford Horne -
The openrisc.net domain expired and was taken over by squatters.
These updates point documentation to the new domain, mailing lists
and git repos.Also, Jonas is not the main maintainer anylonger, he reviews changes
but does not maintain a repo or sent pull requests. Updating this to
add Stafford and Stefan who are the active maintainers.Acked-by: Olof Kindgren
Signed-off-by: Stafford Horne -
Clearing out one todo item. Use the memblock boot time memory
which is the current standard.Tested-by: Guenter Roeck
Acked-by: Jonas
Signed-off-by: Stafford Horne -
The of_platform_populate call in the openrisc arch code is now redundant
as the DT core provides a default call. Openrisc has a NULL match table
which means only top level nodes with compatible strings will have
devices creates. The default version will also descend nodes in the
match table such as "simple-bus" which should be fine as openrisc
doesn't have any of these (though it is preferred that memory-mapped
peripherals be grouped under a bus node(s)).Signed-off-by: Rob Herring
Cc: Jonas Bonn
Tested-by: Guenter Roeck
Signed-off-by: Stafford Horne -
The build system now expects that NR_CPUS is defined.
Follow 4cbbbb4 ("microblaze: Fix missing NR_CPUS in menuconfig")
Signed-off-by: Stafford Horne
-
The output file format for or1k has changed from "elf32-or32"
to "elf32-or1k". Select the correct output format automatically
to be able to compile the kernel with both toolchain variants.Signed-off-by: Guenter Roeck
Tested-by: Guenter Roeck
Signed-off-by: Stafford Horne -
Historically OpenRISC GCC has reserved r10 which we now use to hold
the thread pointer for thread-local storage (TLS).Signed-off-by: Christian Svensson
Signed-off-by: Stefan Kristiansson
Tested-by: Guenter Roeck
Signed-off-by: Stafford Horne -
Fix signal handling for when signals are handled as the result of timers
or exceptions, previous code assumed syscalls. This was noticeable with X
crashing where it uses SIGALRM.This patch restores all regs before returning to userspace via
_resume_userspace instead of via syscall return path.The rt_sigreturn syscall is more like a context switch than a function
call; it entails a return from one context (the signal handler) to another
(the process in question). For a context switch like this there are
effectively no call-saved regs that remain constant across the transition.Reported-by: Sebastian Macke
Signed-off-by: Jonas Bonn
Tested-by: Guenter Roeck
[shorne@gmail.com: Updated comment better reflect change and issue]
Signed-off-by: Stafford Horne -
On OpenRISC, with its 8k pages, PAGE_SHIFT is defined to be 13.
That makes the expression (1UL << (PAGE_SHIFT-2)) evaluate
to 2048.
The correct value for PTRS_PER_PGD should be 256.Correcting the PTRS_PER_PGD define unveiled a bug in map_ram(),
where PTRS_PER_PGD was used when the intent was to iterate
over a set of page table entries.
This patch corrects that issue as well.Signed-off-by: Stefan Kristiansson
Acked-by: Jonas Bonn
Tested-by: Guenter Roeck
Signed-off-by: Stafford Horne
17 Nov, 2016
1 commit
-
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
Signed-off-by: Christian Borntraeger
Reviewed-by: David Hildenbrand
Acked-by: Russell King
Cc: Andrew Morton
Cc: Catalin Marinas
Cc: Heiko Carstens
Cc: Linus Torvalds
Cc: Martin Schwidefsky
Cc: Nicholas Piggin
Cc: Noam Camus
Cc: Paul E. McKenney
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Will Deacon
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-s390
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
16 Nov, 2016
2 commits
-
As there are no users left, we can remove cpu_relax_lowlatency()
implementations from every architecture.Signed-off-by: Christian Borntraeger
Signed-off-by: Peter Zijlstra (Intel)
Cc: Catalin Marinas
Cc: Heiko Carstens
Cc: Linus Torvalds
Cc: Martin Schwidefsky
Cc: Nicholas Piggin
Cc: Noam Camus
Cc: Peter Zijlstra
Cc: Russell King
Cc: Thomas Gleixner
Cc: Will Deacon
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Cc:
Link: http://lkml.kernel.org/r/1477386195-32736-6-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar -
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
Signed-off-by: Peter Zijlstra (Intel)
Cc: Catalin Marinas
Cc: Heiko Carstens
Cc: Linus Torvalds
Cc: Martin Schwidefsky
Cc: Nicholas Piggin
Cc: Noam Camus
Cc: Peter Zijlstra
Cc: Russell King
Cc: Thomas Gleixner
Cc: Will Deacon
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
11 Nov, 2016
1 commit
-
Signed-off-by: Ingo Molnar
07 Nov, 2016
1 commit
-
openrisc qemu tests fail with the following crash.
Unable to handle kernel access at virtual address 0xc0300c34
Oops#: 0001
CPU #: 0
PC: c016c710 SR: 0000ae67 SP: c1017e04
GPR00: 00000000 GPR01: c1017e04 GPR02: c0300c34 GPR03: c0300c34
GPR04: 00000000 GPR05: c0300cb0 GPR06: c0300c34 GPR07: 000000ff
GPR08: c107f074 GPR09: c0199ef4 GPR10: c1016000 GPR11: 00000000
GPR12: 00000000 GPR13: c107f044 GPR14: c0473774 GPR15: 07ce0000
GPR16: 00000000 GPR17: c107ed8a GPR18: 00009600 GPR19: c107f044
GPR20: c107ee74 GPR21: 00000003 GPR22: c0473770 GPR23: 00000033
GPR24: 000000bf GPR25: 00000019 GPR26: c046400c GPR27: 00000001
GPR28: c0464028 GPR29: c1018000 GPR30: 00000006 GPR31: ccf37483
RES: 00000000 oGPR11: ffffffff
Process swapper (pid: 1, stackpage=c1001960)Stack: Stack dump [0xc1017cf8]:
sp + 00: 0xc1017e04
sp + 04: 0xc0300c34
sp + 08: 0xc0300c34
sp + 12: 0x00000000
...Bisect points to commit d2ec3f77de8e ("pty: make ptmx file ops read-only
after init"). Fix by defining __ro_after_init for the openrisc
architecture, similar to parisc.Fixes: d2ec3f77de8e ("pty: make ptmx file ops read-only after init")
Cc: Kees Cook
Signed-off-by: Guenter Roeck
Acked-by: Stafford Horne
25 Oct, 2016
1 commit
-
Its all generic atomic_long_t stuff now.
Tested-by: Jason Low
Signed-off-by: Peter Zijlstra (Intel)
Cc: Andrew Morton
Cc: Linus Torvalds
Cc: Paul E. McKenney
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar
12 Oct, 2016
1 commit
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Pull uaccess.h prepwork from Al Viro:
"Preparations to tree-wide switch to use of linux/uaccess.h (which,
obviously, will allow to start unifying stuff for real). The last step
there, iePATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
sed -i -e "s!$PATT!#include !" \
`git grep -l "$PATT"|grep -v ^include/linux/uaccess.h`is not taken here - I would prefer to do it once just before or just
after -rc1. However, everything should be ready for it"* 'work.uaccess2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
remove a stray reference to asm/uaccess.h in docs
sparc64: separate extable_64.h, switch elf_64.h to it
score: separate extable.h, switch module.h to it
mips: separate extable.h, switch module.h to it
x86: separate extable.h, switch sections.h to it
remove stray include of asm/uaccess.h from cacheflush.h
mn10300: remove a bogus processor.h->uaccess.h include
xtensa: split uaccess.h into C and asm sides
bonding: quit messing with IOCTL
kill __kernel_ds_p off
mn10300: finish verify_area() off
frv: move HAVE_ARCH_UNMAPPED_AREA to pgtable.h
exceptions: detritus removal
08 Oct, 2016
1 commit
-
When doing an nmi backtrace of many cores, most of which are idle, the
output is a little overwhelming and very uninformative. Suppress
messages for cpus that are idling when they are interrupted and just
emit one line, "NMI backtrace for N skipped: idling at pc 0xNNN".We do this by grouping all the cpuidle code together into a new
.cpuidle.text section, and then checking the address of the interrupted
PC to see if it lies within that section.This commit suitably tags x86 and tile idle routines, and only adds in
the minimal framework for other architectures.Link: http://lkml.kernel.org/r/1472487169-14923-5-git-send-email-cmetcalf@mellanox.com
Signed-off-by: Chris Metcalf
Acked-by: Peter Zijlstra (Intel)
Tested-by: Peter Zijlstra (Intel)
Tested-by: Daniel Thompson [arm]
Tested-by: Petr Mladek
Cc: Aaron Tomlin
Cc: Peter Zijlstra (Intel)
Cc: "Rafael J. Wysocki"
Cc: Russell King
Cc: Thomas Gleixner
Cc: Ingo Molnar
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
28 Sep, 2016
1 commit
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externs and defines for stuff that is never used
Signed-off-by: Al Viro
18 Sep, 2016
1 commit
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Since commit acb2505d0119 ("openrisc: fix copy_from_user()"),
copy_from_user() returns the number of bytes requested, not the
number of bytes not copied.Cc: Al Viro
Fixes: acb2505d0119 ("openrisc: fix copy_from_user()")
Signed-off-by: Guenter Roeck
14 Sep, 2016
1 commit
-
... that should zero on faults. Also remove the helpful
logics wrt range truncation copied from ppc32. Where it had ever
been needed only in case of copy_from_user() *and* had not been merged
into the mainline until a month after the need had disappeared.
A decade before openrisc went into mainline, I might add...Cc: stable@vger.kernel.org
Signed-off-by: Al Viro
04 Aug, 2016
1 commit
-
The dma-mapping core and the implementations do not change the DMA
attributes passed by pointer. Thus the pointer can point to const data.
However the attributes do not have to be a bitfield. Instead unsigned
long will do fine:1. This is just simpler. Both in terms of reading the code and setting
attributes. Instead of initializing local attributes on the stack
and passing pointer to it to dma_set_attr(), just set the bits.2. It brings safeness and checking for const correctness because the
attributes are passed by value.Semantic patches for this change (at least most of them):
virtual patch
virtual context@r@
identifier f, attrs;@@
f(...,
- struct dma_attrs *attrs
+ unsigned long attrs
, ...)
{
...
}@@
identifier r.f;
@@
f(...,
- NULL
+ 0
)and
// Options: --all-includes
virtual patch
virtual context@r@
identifier f, attrs;
type t;@@
t f(..., struct dma_attrs *attrs);@@
identifier r.f;
@@
f(...,
- NULL
+ 0
)Link: http://lkml.kernel.org/r/1468399300-5399-2-git-send-email-k.kozlowski@samsung.com
Signed-off-by: Krzysztof Kozlowski
Acked-by: Vineet Gupta
Acked-by: Robin Murphy
Acked-by: Hans-Christian Noren Egtvedt
Acked-by: Mark Salter [c6x]
Acked-by: Jesper Nilsson [cris]
Acked-by: Daniel Vetter [drm]
Reviewed-by: Bart Van Assche
Acked-by: Joerg Roedel [iommu]
Acked-by: Fabien Dessenne [bdisp]
Reviewed-by: Marek Szyprowski [vb2-core]
Acked-by: David Vrabel [xen]
Acked-by: Konrad Rzeszutek Wilk [xen swiotlb]
Acked-by: Joerg Roedel [iommu]
Acked-by: Richard Kuo [hexagon]
Acked-by: Geert Uytterhoeven [m68k]
Acked-by: Gerald Schaefer [s390]
Acked-by: Bjorn Andersson
Acked-by: Hans-Christian Noren Egtvedt [avr32]
Acked-by: Vineet Gupta [arc]
Acked-by: Robin Murphy [arm64 and dma-iommu]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
03 Aug, 2016
1 commit
-
There was only one use of __initdata_refok and __exit_refok
__init_refok was used 46 times against 82 for __ref.
Those definitions are obsolete since commit 312b1485fb50 ("Introduce new
section reference annotations tags: __ref, __refdata, __refconst")This patch removes the following compatibility definitions and replaces
them treewide./* compatibility defines */
#define __init_refok __ref
#define __initdata_refok __refdata
#define __exit_refok __refI can also provide separate patches if necessary.
(One patch per tree and check in 1 month or 2 to remove old definitions)[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/1466796271-3043-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick
Cc: Ingo Molnar
Cc: Sam Ravnborg
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
27 Jul, 2016
3 commits
-
Merge updates from Andrew Morton:
- a few misc bits
- ocfs2
- most(?) of MM
* emailed patches from Andrew Morton : (125 commits)
thp: fix comments of __pmd_trans_huge_lock()
cgroup: remove unnecessary 0 check from css_from_id()
cgroup: fix idr leak for the first cgroup root
mm: memcontrol: fix documentation for compound parameter
mm: memcontrol: remove BUG_ON in uncharge_list
mm: fix build warnings in
mm, thp: convert from optimistic swapin collapsing to conservative
mm, thp: fix comment inconsistency for swapin readahead functions
thp: update Documentation/{vm/transhuge,filesystems/proc}.txt
shmem: split huge pages beyond i_size under memory pressure
thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE
khugepaged: add support of collapse for tmpfs/shmem pages
shmem: make shmem_inode_info::lock irq-safe
khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page()
thp: extract khugepaged from mm/huge_memory.c
shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings
shmem: add huge pages support
shmem: get_unmapped_area align huge page
shmem: prepare huge= mount option and sysfs knob
mm, rmap: account shmem thp pages
... -
Pull GPIO updates from Linus Walleij:
"This is the bulk of GPIO changes for the v4.8 kernel cycle. The big
news is the completion of the chardev ABI which I'm very happy about
and apart from that it's an ordinary, quite busy cycle. The details
are below.The patches are tested in linux-next for some time, patches to other
subsystem mostly have ACKs.I got overly ambitious with configureing lines as input for IRQ lines
but it turns out that some controllers have their interrupt-enable and
input-enabling in orthogonal settings so the assumption that all IRQ
lines are input lines does not hold. Oh well, revert and back to the
drawing board with that.Core changes:
- The big item is of course the completion of the character device
ABI. It has now replaced and surpassed the former unmaintainable
sysfs ABI: we can now hammer (bitbang) individual lines or sets of
lines and read individual lines or sets of lines from userspace,
and we can also register to listen to GPIO events from userspace.As a tie-in we have two new tools in tools/gpio: gpio-hammer and
gpio-event-mon that illustrate the proper use of the new ABI. As
someone said: the wild west days of GPIO are now over.- Continued to remove the pointless ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB
Kconfig symbols. I'm patching hexagon, openrisc, powerpc, sh,
unicore, ia64 and microblaze. These are either ACKed by their
maintainers or patched anyways after a grace period and no response
from maintainers.Some archs (ARM) come in from their trees, and others (x86) are
still not fixed, so I might send a second pull request to root it
out later in this merge window, or just defer to v4.9.- The GPIO tools are moved to the tools build system.
New drivers:
- New driver for the MAX77620/MAX20024.
- New driver for the Intel Merrifield.
- Enabled PCA953x for the TI PCA9536.
- Enabled PCA953x for the Intel Edison.
- Enabled R8A7792 in the RCAR driver.
Driver improvements:
- The STMPE and F7188x now supports the .get_direction() callback.
- The Xilinx driver supports setting multiple lines at once.
- ACPI support for the Vulcan GPIO controller.
- The MMIO GPIO driver supports device tree probing.
- The Acer One 10 is supported through the _DEP ACPI attribute.
Cleanups:
- A major cleanup of the OF/DT support code. It is way easier to
read and understand now, probably this improves performance too.- Drop a few redundant .owner assignments.
- Remove CLPS711x boardfile support: we are 100% DT"
* tag 'gpio-v4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (67 commits)
MAINTAINERS: Add INTEL MERRIFIELD GPIO entry
gpio: dwapb: add missing fwnode_handle_put() in dwapb_gpio_get_pdata()
gpio: merrifield: Protect irq_ack() and gpio_set() by lock
gpio: merrifield: Introduce GPIO driver to support Merrifield
gpio: intel-mid: Make it depend to X86_INTEL_MID
gpio: intel-mid: Sort header block alphabetically
gpio: intel-mid: Remove potentially harmful code
gpio: rcar: add R8A7792 support
gpiolib: remove duplicated include from gpiolib.c
Revert "gpio: convince line to become input in irq helper"
gpiolib: of_find_gpio(): Don't discard errors
gpio: of: Allow overriding the device node
gpio: free handles in fringe cases
gpio: tps65218: Add platform_device_id table
gpio: max77620: get gpio value based on direction
gpio: lynxpoint: avoid potential warning on error path
tools/gpio: add install section
tools/gpio: move to tools buildsystem
gpio: intel-mid: switch to devm_gpiochip_add_data()
gpio: 74x164: Use spi_write() helper instead of open coding
... -
We always have vma->vm_mm around.
Link: http://lkml.kernel.org/r/1466021202-61880-8-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
25 Jun, 2016
1 commit
-
This is the third version of the patchset previously sent [1]. I have
basically only rebased it on top of 4.7-rc1 tree and dropped "dm: get
rid of superfluous gfp flags" which went through dm tree. I am sending
it now because it is tree wide and chances for conflicts are reduced
considerably when we want to target rc2. I plan to send the next step
and rename the flag and move to a better semantic later during this
release cycle so we will have a new semantic ready for 4.8 merge window
hopefully.Motivation:
While working on something unrelated I've checked the current usage of
__GFP_REPEAT in the tree. It seems that a majority of the usage is and
always has been bogus because __GFP_REPEAT has always been about costly
high order allocations while we are using it for order-0 or very small
orders very often. It seems that a big pile of them is just a
copy&paste when a code has been adopted from one arch to another.I think it makes some sense to get rid of them because they are just
making the semantic more unclear. Please note that GFP_REPEAT is
documented as* __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
* _might_ fail. This depends upon the particular VM implementation.
while !costly requests have basically nofail semantic. So one could
reasonably expect that order-0 request with __GFP_REPEAT will not loop
for ever. This is not implemented right now though.I would like to move on with __GFP_REPEAT and define a better semantic
for it.$ git grep __GFP_REPEAT origin/master | wc -l
111
$ git grep __GFP_REPEAT | wc -l
36So we are down to the third after this patch series. The remaining
places really seem to be relying on __GFP_REPEAT due to large allocation
requests. This still needs some double checking which I will do later
after all the simple ones are sorted out.I am touching a lot of arch specific code here and I hope I got it right
but as a matter of fact I even didn't compile test for some archs as I
do not have cross compiler for them. Patches should be quite trivial to
review for stupid compile mistakes though. The tricky parts are usually
hidden by macro definitions and thats where I would appreciate help from
arch maintainers.[1] http://lkml.kernel.org/r/1461849846-27209-1-git-send-email-mhocko@kernel.org
This patch (of 19):
__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. Yet we
have the full kernel tree with its usage for apparently order-0
allocations. This is really confusing because __GFP_REPEAT is
explicitly documented to allow allocation failures which is a weaker
semantic than the current order-0 has (basically nofail).Let's simply drop __GFP_REPEAT from those places. This would allow to
identify place which really need allocator to retry harder and formulate
a more specific semantic for what the flag is supposed to do actually.Link: http://lkml.kernel.org/r/1464599699-30131-2-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko
Cc: "David S. Miller"
Cc: "H. Peter Anvin"
Cc: "James E.J. Bottomley"
Cc: "Theodore Ts'o"
Cc: Andy Lutomirski
Cc: Benjamin Herrenschmidt
Cc: Catalin Marinas
Cc: Chen Liqin
Cc: Chris Metcalf [for tile]
Cc: Guan Xuetao
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Jan Kara
Cc: John Crispin
Cc: Lennox Wu
Cc: Ley Foon Tan
Cc: Martin Schwidefsky
Cc: Matt Fleming
Cc: Ralf Baechle
Cc: Rich Felker
Cc: Russell King
Cc: Thomas Gleixner
Cc: Vineet Gupta
Cc: Will Deacon
Cc: Yoshinori Sato
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 Jun, 2016
1 commit
-
Replace "select ARCH_REQUIRE_GPIOLIB" with "select GPIOLIB"
as this can now be selected directly.Cc: Michael Büsch
Cc: Jonas Bonn
Cc: linux@lists.openrisc.net
Signed-off-by: Linus Walleij
25 May, 2016
1 commit
-
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
21 May, 2016
2 commits
-
The binary GCD algorithm is based on the following facts:
1. If a and b are all evens, then gcd(a,b) = 2 * gcd(a/2, b/2)
2. If a is even and b is odd, then gcd(a,b) = gcd(a/2, b)
3. If a and b are all odds, then gcd(a,b) = gcd((a-b)/2, b) = gcd((a+b)/2, b)Even on x86 machines with reasonable division hardware, the binary
algorithm runs about 25% faster (80% the execution time) than the
division-based Euclidian algorithm.On platforms like Alpha and ARMv6 where division is a function call to
emulation code, it's even more significant.There are two variants of the code here, depending on whether a fast
__ffs (find least significant set bit) instruction is available. This
allows the unpredictable branches in the bit-at-a-time shifting loop to
be eliminated.If fast __ffs is not available, the "even/odd" GCD variant is used.
I use the following code to benchmark:
#include
#include
#include
#include
#include
#include#define swap(a, b) \
do { \
a ^= b; \
b ^= a; \
a ^= b; \
} while (0)unsigned long gcd0(unsigned long a, unsigned long b)
{
unsigned long r;if (a < b) {
swap(a, b);
}if (b == 0)
return a;while ((r = a % b) != 0) {
a = b;
b = r;
}return b;
}unsigned long gcd1(unsigned long a, unsigned long b)
{
unsigned long r = a | b;if (!a || !b)
return r;b >>= __builtin_ctzl(b);
for (;;) {
a >>= __builtin_ctzl(a);
if (a == b)
return a << __builtin_ctzl(r);if (a < b)
swap(a, b);
a -= b;
}
}unsigned long gcd2(unsigned long a, unsigned long b)
{
unsigned long r = a | b;if (!a || !b)
return r;r &= -r;
while (!(b & r))
b >>= 1;for (;;) {
while (!(a & r))
a >>= 1;
if (a == b)
return a;if (a < b)
swap(a, b);
a -= b;
a >>= 1;
if (a & r)
a += b;
a >>= 1;
}
}unsigned long gcd3(unsigned long a, unsigned long b)
{
unsigned long r = a | b;if (!a || !b)
return r;b >>= __builtin_ctzl(b);
if (b == 1)
return r & -r;for (;;) {
a >>= __builtin_ctzl(a);
if (a == 1)
return r & -r;
if (a == b)
return a << __builtin_ctzl(r);if (a < b)
swap(a, b);
a -= b;
}
}unsigned long gcd4(unsigned long a, unsigned long b)
{
unsigned long r = a | b;if (!a || !b)
return r;r &= -r;
while (!(b & r))
b >>= 1;
if (b == r)
return r;for (;;) {
while (!(a & r))
a >>= 1;
if (a == r)
return r;
if (a == b)
return a;if (a < b)
swap(a, b);
a -= b;
a >>= 1;
if (a & r)
a += b;
a >>= 1;
}
}static unsigned long (*gcd_func[])(unsigned long a, unsigned long b) = {
gcd0, gcd1, gcd2, gcd3, gcd4,
};#define TEST_ENTRIES (sizeof(gcd_func) / sizeof(gcd_func[0]))
#if defined(__x86_64__)
#define rdtscll(val) do { \
unsigned long __a,__d; \
__asm__ __volatile__("rdtsc" : "=a" (__a), "=d" (__d)); \
(val) = ((unsigned long long)__a) | (((unsigned long long)__d)<= start)
ret = end - start;
else
ret = ~0ULL - start + 1 + end;*res = gcd_res;
return ret;
}#else
static inline struct timespec read_time(void)
{
struct timespec time;
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time);
return time;
}static inline unsigned long long diff_time(struct timespec start, struct timespec end)
{
struct timespec temp;if ((end.tv_nsec - start.tv_nsec) < 0) {
temp.tv_sec = end.tv_sec - start.tv_sec - 1;
temp.tv_nsec = 1000000000ULL + end.tv_nsec - start.tv_nsec;
} else {
temp.tv_sec = end.tv_sec - start.tv_sec;
temp.tv_nsec = end.tv_nsec - start.tv_nsec;
}return temp.tv_sec * 1000000000ULL + temp.tv_nsec;
}static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long),
unsigned long a, unsigned long b, unsigned long *res)
{
struct timespec start, end;
unsigned long gcd_res;start = read_time();
gcd_res = gcd(a, b);
end = read_time();*res = gcd_res;
return diff_time(start, end);
}#endif
static inline unsigned long get_rand()
{
if (sizeof(long) == 8)
return (unsigned long)rand() << 32 | rand();
else
return rand();
}int main(int argc, char **argv)
{
unsigned int seed = time(0);
int loops = 100;
int repeats = 1000;
unsigned long (*res)[TEST_ENTRIES];
unsigned long long elapsed[TEST_ENTRIES];
int i, j, k;for (;;) {
int opt = getopt(argc, argv, "n:r:s:");
/* End condition always first */
if (opt == -1)
break;switch (opt) {
case 'n':
loops = atoi(optarg);
break;
case 'r':
repeats = atoi(optarg);
break;
case 's':
seed = strtoul(optarg, NULL, 10);
break;
default:
/* You won't actually get here. */
break;
}
}res = malloc(sizeof(unsigned long) * TEST_ENTRIES * loops);
memset(elapsed, 0, sizeof(elapsed));srand(seed);
for (j = 0; j < loops; j++) {
unsigned long a = get_rand();
/* Do we have args? */
unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
unsigned long long min_elapsed[TEST_ENTRIES];
for (k = 0; k < repeats; k++) {
for (i = 0; i < TEST_ENTRIES; i++) {
unsigned long long tmp = benchmark_gcd_func(gcd_func[i], a, b, &res[j][i]);
if (k == 0 || min_elapsed[i] > tmp)
min_elapsed[i] = tmp;
}
}
for (i = 0; i < TEST_ENTRIES; i++)
elapsed[i] += min_elapsed[i];
}for (i = 0; i < TEST_ENTRIES; i++)
printf("gcd%d: elapsed %llu\n", i, elapsed[i]);k = 0;
srand(seed);
for (j = 0; j < loops; j++) {
unsigned long a = get_rand();
unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
for (i = 1; i < TEST_ENTRIES; i++) {
if (res[j][i] != res[j][0])
break;
}
if (i < TEST_ENTRIES) {
if (k == 0) {
k = 1;
fprintf(stderr, "Error:\n");
}
fprintf(stderr, "gcd(%lu, %lu): ", a, b);
for (i = 0; i < TEST_ENTRIES; i++)
fprintf(stderr, "%ld%s", res[j][i], i < TEST_ENTRIES - 1 ? ", " : "\n");
}
}if (k == 0)
fprintf(stderr, "PASS\n");free(res);
return 0;
}Compiled with "-O2", on "VirtualBox 4.4.0-22-generic #38-Ubuntu x86_64" got:
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 10174
gcd1: elapsed 2120
gcd2: elapsed 2902
gcd3: elapsed 2039
gcd4: elapsed 2812
PASS
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 9309
gcd1: elapsed 2280
gcd2: elapsed 2822
gcd3: elapsed 2217
gcd4: elapsed 2710
PASS
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 9589
gcd1: elapsed 2098
gcd2: elapsed 2815
gcd3: elapsed 2030
gcd4: elapsed 2718
PASS
zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
gcd0: elapsed 9914
gcd1: elapsed 2309
gcd2: elapsed 2779
gcd3: elapsed 2228
gcd4: elapsed 2709
PASS[akpm@linux-foundation.org: avoid #defining a CONFIG_ variable]
Signed-off-by: Zhaoxiu Zeng
Signed-off-by: George Spelvin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Define HAVE_EXIT_THREAD for archs which want to do something in
exit_thread. For others, let's define exit_thread as an empty inline.This is a cleanup before we change the prototype of exit_thread to
accept a task parameter.[akpm@linux-foundation.org: fix mips]
Signed-off-by: Jiri Slaby
Cc: "David S. Miller"
Cc: "H. Peter Anvin"
Cc: "James E.J. Bottomley"
Cc: Aurelien Jacquiot
Cc: Benjamin Herrenschmidt
Cc: Catalin Marinas
Cc: Chen Liqin
Cc: Chris Metcalf
Cc: Chris Zankel
Cc: David Howells
Cc: Fenghua Yu
Cc: Geert Uytterhoeven
Cc: Guan Xuetao
Cc: Haavard Skinnemoen
Cc: Hans-Christian Egtvedt
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Ivan Kokshaysky
Cc: James Hogan
Cc: Jeff Dike
Cc: Jesper Nilsson
Cc: Jiri Slaby
Cc: Jonas Bonn
Cc: Koichi Yasutake
Cc: Lennox Wu
Cc: Ley Foon Tan
Cc: Mark Salter
Cc: Martin Schwidefsky
Cc: Matt Turner
Cc: Max Filippov
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Mikael Starvik
Cc: Paul Mackerras
Cc: Peter Zijlstra
Cc: Ralf Baechle
Cc: Rich Felker
Cc: Richard Henderson
Cc: Richard Kuo
Cc: Richard Weinberger
Cc: Russell King
Cc: Steven Miao
Cc: Thomas Gleixner
Cc: Tony Luck
Cc: Vineet Gupta
Cc: Will Deacon
Cc: Yoshinori Sato
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
05 May, 2016
1 commit
-
The newer renameat2 syscall provides all the functionality provided by
the renameat syscall and adds flags, so future architectures won't need
to include renameat.Therefore drop the renameat syscall from the generic syscall list unless
__ARCH_WANT_RENAMEAT is defined by the architecture's unistd.h prior to
including asm-generic/unistd.h, and adjust all architectures using the
generic syscall list to define it so that no in-tree architectures are
affected.Signed-off-by: James Hogan
Acked-by: Vineet Gupta
Cc: linux-arch@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: Catalin Marinas
Cc: Will Deacon
Cc: linux-arm-kernel@lists.infradead.org
Cc: Mark Salter
Cc: Aurelien Jacquiot
Cc: linux-c6x-dev@linux-c6x.org
Cc: Richard Kuo
Cc: linux-hexagon@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: Jonas Bonn
Cc: linux@lists.openrisc.net
Cc: Chen Liqin
Cc: Lennox Wu
Cc: Chris Metcalf
Cc: Guan Xuetao
Cc: Ley Foon Tan
Cc: nios2-dev@lists.rocketboards.org
Cc: Yoshinori Sato
Cc: uclinux-h8-devel@lists.sourceforge.jp
Signed-off-by: Arnd Bergmann
22 Apr, 2016
1 commit
-
To align with generic code and other architectures that expect the macro
page_to_virt to produce an expression whose type is 'void*', drop the
arch specific definition, which is never referenced anyway.Acked-by: Andrew Morton
Signed-off-by: Ard Biesheuvel
Signed-off-by: Will Deacon
26 Mar, 2016
1 commit
-
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.Move the definition of __irq_entry to so that the
users don't need to pull in . Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.Signed-off-by: Alexander Potapenko
Acked-by: Steven Rostedt
Cc: Christoph Lameter
Cc: Pekka Enberg
Cc: David Rientjes
Cc: Joonsoo Kim
Cc: Andrey Konovalov
Cc: Dmitry Vyukov
Cc: Andrey Ryabinin
Cc: Konstantin Serebryany
Cc: Dmitry Chernenkov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
25 Mar, 2016
1 commit
-
Pull asm-generic updates from Arnd Bergmann:
"There are only three patches this time, most other changes to files in
include/asm-generic tend to go through the tree of whoever depends on
the change.Two patches are cleanups for stuff that is no longer needed, the main
change is to adapt the generic version of BUG_ON() for CONFIG_BUG=n to
make it behave consistently with BUG().This avoids undefined behavior along with a number of warnings about
that undefined behavior in randconfig builds when we keep going on
after hitting a BUG_ON()"* tag 'asm-generic-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
asm-generic: remove old nonatomic-io wrapper files
asm-generic: default BUG_ON(x) to if(x)BUG()
asm-generic: page.h: Remove useless get_user_page and free_user_page
26 Feb, 2016
1 commit
-
They are not symmetric with each other, neither are used in real world
(can not be found by grep command in source code root directory), so
remove them.Signed-off-by: Chen Gang
Acked-by: Russell King
Acked-by: Greg Ungerer
Signed-off-by: Arnd Bergmann
