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c17b0aadb7
I have one regression fix for a minor build problem after the architecture removal series, plus a rework of the barriers in the readl/writel functions, thanks to work by Sinan Kaya: This started from a discussion on the linuxpcc and rdma mailing lists [1]. To summarize, we decided that architectures are responsible to serialize readl() and writel() accesses on a device MMIO space relative to DMA performed by that device. This series provides a pessimistic implementation of that behavior for asm-generic/io.h, which is in turn used by a number of architectures (h8300, microblaze, nios2, openrisc, s390, sparc, um, unicore32, and xtensa). Some of those presumably need no extra barriers, or something weaker than rmb()/wmb(), and they are advised to override the new default for better performance. For inb()/outb(), the same barriers are used, but architectures might want to add another barrier to outb() here if that can guarantee non-posted behavior (some architectures can, others cannot do that). The readl_relaxed()/writel_relaxed() family of functions retains the existing behavior with no extra barriers. [1]: https://lists.ozlabs.org/pipermail/linuxppc-dev/2018-March/170481.html -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJazitHAAoJEGCrR//JCVInd0wP/iMzr1HWDgMjeeuxekFjwWDg 9fL+BFt1afeYb4wniqJcF7ymLow/H5Fbhj4dwM1p34De+CZ3+3JGNyK8qzoeKPjR I2U5QqjWCHWDqpWRGWxO28dbs5/1EoW1zgctTNMUPHiamnomz9XIn0xaVKpu4HZ3 OtaeJm8seKTSj1+A2fye9sDpqMUJuVcnZAWJgqMJ8T98uMBOiJYWHftnFEJpSlwG SJSt4AYsJnE+3BFawX1g3VWrHn9WN1uwVasJ1INFkLYNuLMYaK7RYjoBWNwHW+RQ luq4xZE+HZehyZptilfs05x2IlhGSOVN5m0nVM2if9aXoEoO1UdaySbwO6Ukq085 VyfCzY+k4l0v44o4JqaSyAFLEae0809E6cQcGg3cjdstQv1Q3cgAJ96myP0x+QTw b0xJGoo46eOfqpK4njARyjTSceYPgzkB5Dqngg9rCuh+EogotWpRRDB6zoeGGRK8 oOzMp0qLsAZFcYvjft5h0Cp6X51qfyJpBkJkvnASmF4yJPZlpCRGux+HM3jFb9bV zbH+KPqTa47OmOK8MNIaFHMR1yMgZU6B2oEwFDEaG0M+6FC5irMSkgcDwIIMJXlJ wLp7+4WhwFzFDe1mp/tKM5V4h9D6vQtSUjgOJffhxRXqCMkxc7eABmYBBkjMCsca ibKXyZN16d1kRU9j7upb =oBQh -----END PGP SIGNATURE----- Merge tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic fixes from Arnd Bergmann: "I have one regression fix for a minor build problem after the architecture removal series, plus a rework of the barriers in the readl/writel functions, thanks to work by Sinan Kaya: This started from a discussion on the linuxpcc and rdma mailing lists[1]. To summarize, we decided that architectures are responsible to serialize readl() and writel() accesses on a device MMIO space relative to DMA performed by that device. This series provides a pessimistic implementation of that behavior for asm-generic/io.h, which is in turn used by a number of architectures (h8300, microblaze, nios2, openrisc, s390, sparc, um, unicore32, and xtensa). Some of those presumably need no extra barriers, or something weaker than rmb()/wmb(), and they are advised to override the new default for better performance. For inb()/outb(), the same barriers are used, but architectures might want to add another barrier to outb() here if that can guarantee non-posted behavior (some architectures can, others cannot do that). The readl_relaxed()/writel_relaxed() family of functions retains the existing behavior with no extra barriers" [1] https://lists.ozlabs.org/pipermail/linuxppc-dev/2018-March/170481.html * tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: io: change writeX_relaxed() to remove barriers io: change readX_relaxed() to remove barriers dts: remove cris & metag dts hard link file io: change inX() to have their own IO barrier overrides io: change outX() to have their own IO barrier overrides io: define stronger ordering for the default writeX() implementation io: define stronger ordering for the default readX() implementation io: define several IO & PIO barrier types for the asm-generic version |
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.. | ||
bitops | ||
4level-fixup.h | ||
5level-fixup.h | ||
asm-offsets.h | ||
asm-prototypes.h | ||
atomic-instrumented.h | ||
atomic-long.h | ||
atomic.h | ||
atomic64.h | ||
audit_change_attr.h | ||
audit_dir_write.h | ||
audit_read.h | ||
audit_signal.h | ||
audit_write.h | ||
barrier.h | ||
bitops.h | ||
bitsperlong.h | ||
bug.h | ||
bugs.h | ||
cache.h | ||
cacheflush.h | ||
checksum.h | ||
cmpxchg-local.h | ||
cmpxchg.h | ||
current.h | ||
delay.h | ||
device.h | ||
div64.h | ||
dma-contiguous.h | ||
dma-mapping.h | ||
dma.h | ||
early_ioremap.h | ||
emergency-restart.h | ||
error-injection.h | ||
exec.h | ||
export.h | ||
extable.h | ||
fb.h | ||
fixmap.h | ||
ftrace.h | ||
futex.h | ||
getorder.h | ||
gpio.h | ||
hardirq.h | ||
hugetlb.h | ||
hw_irq.h | ||
ide_iops.h | ||
int-ll64.h | ||
io.h | ||
ioctl.h | ||
iomap.h | ||
irq.h | ||
irq_regs.h | ||
irq_work.h | ||
irqflags.h | ||
kdebug.h | ||
kmap_types.h | ||
kprobes.h | ||
kvm_para.h | ||
linkage.h | ||
local.h | ||
local64.h | ||
mcs_spinlock.h | ||
memory_model.h | ||
mm-arch-hooks.h | ||
mm_hooks.h | ||
mmu.h | ||
mmu_context.h | ||
module.h | ||
msi.h | ||
page.h | ||
param.h | ||
parport.h | ||
pci.h | ||
pci_iomap.h | ||
percpu.h | ||
pgalloc.h | ||
pgtable-nop4d-hack.h | ||
pgtable-nop4d.h | ||
pgtable-nopmd.h | ||
pgtable-nopud.h | ||
pgtable.h | ||
preempt.h | ||
ptrace.h | ||
qrwlock.h | ||
qrwlock_types.h | ||
qspinlock.h | ||
qspinlock_types.h | ||
resource.h | ||
rwsem.h | ||
seccomp.h | ||
sections.h | ||
segment.h | ||
serial.h | ||
set_memory.h | ||
signal.h | ||
simd.h | ||
sizes.h | ||
spinlock.h | ||
statfs.h | ||
string.h | ||
switch_to.h | ||
syscall.h | ||
syscalls.h | ||
termios-base.h | ||
termios.h | ||
timex.h | ||
tlb.h | ||
tlbflush.h | ||
topology.h | ||
trace_clock.h | ||
uaccess.h | ||
unaligned.h | ||
unistd.h | ||
user.h | ||
vga.h | ||
vmlinux.lds.h | ||
vtime.h | ||
word-at-a-time.h | ||
xor.h |