| Age | Commit message (Collapse) | Author |
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It seems following race is possible:
cpu0 cpux
smp_init->cpu_up->_cpu_up
__cpu_up
kick_cpu(1)
-------------------------------------------------------------------------
waiting online ...
... notify CPU_STARTING
set cpux active
set cpux online
-------------------------------------------------------------------------
finish waiting online
...
sched_init_smp
init_sched_domains(cpu_active_mask)
build_sched_domains
set cpux sibling info
-------------------------------------------------------------------------
Execution of cpu0 and cpux could be concurrent between two separator
lines.
So if the cpux sibling information was set too late (normally
impossible, but could be triggered by adding some delay in
start_secondary, after setting cpu online), build_sched_domains()
running on cpu0 might see cpux active, with an empty sibling mask, then
cause some bad address accessing like following:
[ 0.099855] Unable to handle kernel paging request for data at address 0xc00000038518078f
[ 0.099868] Faulting instruction address: 0xc0000000000b7a64
[ 0.099883] Oops: Kernel access of bad area, sig: 11 [#1]
[ 0.099895] PREEMPT SMP NR_CPUS=16 DEBUG_PAGEALLOC NUMA pSeries
[ 0.099922] Modules linked in:
[ 0.099940] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.0-rc1-00120-gb973425-dirty #16
[ 0.099956] task: c0000001fed80000 ti: c0000001fed7c000 task.ti: c0000001fed7c000
[ 0.099971] NIP: c0000000000b7a64 LR: c0000000000b7a40 CTR: c0000000000b4934
[ 0.099985] REGS: c0000001fed7f760 TRAP: 0300 Not tainted (3.10.0-rc1-00120-gb973425-dirty)
[ 0.099997] MSR: 8000000000009032 <SF,EE,ME,IR,DR,RI> CR: 24272828 XER: 20000003
[ 0.100045] SOFTE: 1
[ 0.100053] CFAR: c000000000445ee8
[ 0.100064] DAR: c00000038518078f, DSISR: 40000000
[ 0.100073]
GPR00: 0000000000000080 c0000001fed7f9e0 c000000000c84d48 0000000000000010
GPR04: 0000000000000010 0000000000000000 c0000001fc55e090 0000000000000000
GPR08: ffffffffffffffff c000000000b80b30 c000000000c962d8 00000003845ffc5f
GPR12: 0000000000000000 c00000000f33d000 c00000000000b9e4 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000001 0000000000000000
GPR20: c000000000ccf750 0000000000000000 c000000000c94d48 c0000001fc504000
GPR24: c0000001fc504000 c0000001fecef848 c000000000c94d48 c000000000ccf000
GPR28: c0000001fc522090 0000000000000010 c0000001fecef848 c0000001fed7fae0
[ 0.100293] NIP [c0000000000b7a64] .get_group+0x84/0xc4
[ 0.100307] LR [c0000000000b7a40] .get_group+0x60/0xc4
[ 0.100318] Call Trace:
[ 0.100332] [c0000001fed7f9e0] [c0000000000dbce4] .lock_is_held+0xa8/0xd0 (unreliable)
[ 0.100354] [c0000001fed7fa70] [c0000000000bf62c] .build_sched_domains+0x728/0xd14
[ 0.100375] [c0000001fed7fbe0] [c000000000af67bc] .sched_init_smp+0x4fc/0x654
[ 0.100394] [c0000001fed7fce0] [c000000000adce24] .kernel_init_freeable+0x17c/0x30c
[ 0.100413] [c0000001fed7fdb0] [c00000000000ba08] .kernel_init+0x24/0x12c
[ 0.100431] [c0000001fed7fe30] [c000000000009f74] .ret_from_kernel_thread+0x5c/0x68
[ 0.100445] Instruction dump:
[ 0.100456] 38800010 38a00000 4838e3f5 60000000 7c6307b4 2fbf0000 419e0040 3d220001
[ 0.100496] 78601f24 39491590 e93e0008 7d6a002a <7d69582a> f97f0000 7d4a002a e93e0010
[ 0.100559] ---[ end trace 31fd0ba7d8756001 ]---
This patch tries to move the sibling maps updating before
notify_cpu_starting() and cpu online, and a write barrier there to make
sure sibling maps are updated before active and online mask.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications. For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.
After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out. Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.
This removes all the powerpc uses of the __cpuinit macros. There
are no __CPUINIT users in assembly files in powerpc.
[1] https://lkml.org/lkml/2013/5/20/589
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Josh Boyer <jwboyer@gmail.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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This typedef is unnecessary and should just be removed.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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pci_iommu_init() and pci_direct_iommu_init() are not referenced anywhere,
so remove them.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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For an unknown relocation type since the value of r4 is just the 8bit
relocation type, the sum of r4 and r7 may yield an invalid memory
address. For example:
In normal case:
r4 = c00xxxxx
r7 = 40000000
r4 + r7 = 000xxxxx
For an unknown relocation type:
r4 = 000000xx
r7 = 40000000
r4 + r7 = 400000xx
400000xx is an invalid memory address for a board which has just
512M memory.
And for operations such as dcbst or icbi may cause bus error for an
invalid memory address on some platforms and then cause the board
reset. So we should skip the flush/invalidate the d/icache for
an unknown relocation type.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Acked-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Currently, we're using the combo (PCI bus + devfn) in the PCI
config accessors and PCI config accessors in EEH depends on them.
However, it's not safe to refer the PCI bus which might have been
removed during hotplug. So we're using device node in the PCI
config accessors and the corresponding backends just reuse them.
The patch also fix one potential risk: We possiblly have frozen
PE during the early PCI probe time, but we haven't setup the PE
mapping yet. So the errors should be counted to PE#0.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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The patch is for avoiding following build warnings:
The function .pnv_pci_ioda_fixup() references
the function __init .eeh_init().
This is often because .pnv_pci_ioda_fixup lacks a __init
The function .pnv_pci_ioda_fixup() references
the function __init .eeh_addr_cache_build().
This is often because .pnv_pci_ioda_fixup lacks a __init
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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We needn't the the whole backtrace other than one-line message in
the error reporting interrupt handler. For errors triggered by
access PCI config space or MMIO, we replace "WARN(1, ...)" with
pr_err() and dump_stack(). The patch also adds more output messages
to indicate what EEH core is doing. Besides, some printk() are
replaced with pr_warning().
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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On the PowerNV platform, the EEH address cache isn't built correctly
because we skipped the EEH devices without binding PE. The patch
fixes that.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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We have 2 fields in "struct pnv_phb" to trace the states. The patch
replace the fields with one and introduces flags for that. The patch
doesn't impact the logic.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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After reset (e.g. complete reset) in order to bring the fenced PHB
back, the PCIe link might not be ready yet. The patch intends to
make sure the PCIe link is ready before accessing its subordinate
PCI devices. The patch also fixes that wrong values restored to
PCI_COMMAND register for PCI bridges.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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When the PHB is fenced or dead, it's pointless to collect the data
from PCI config space of subordinate PCI devices since it should
return 0xFF's. The patch also fixes overwritten buffer while getting
PCI config data.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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This patch modifies the platform data of max8998 to use arrays for
specifying predefined voltages of buck1 and buck2 instead of separate
field for each voltage.
This allows to simplify the code a bit and will help in adding support
for Device Tree, which will be introduced in further patch.
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Acked-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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When we treclaim and trecheckpoint there's an unavoidable period when r1
will not be a valid kernel stack pointer.
This patch clears the MSR recoverable interrupt (RI) bit over these
regions to indicate we have an invalid kernel stack pointer.
For treclaim, the region over which we clear MSR RI is larger than
required to avoid the need for an extra costly mtmsrd.
Thanks to Paulus for suggesting this change.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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String instruction emulation would erroneously result in a segfault if
the upper bits of the EA are set and is so high that it fails access
check. Truncate the EA to 32 bits if the process is 32-bit.
Signed-off-by: James Yang <James.Yang@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Signed-off-by: Sebastien Bessiere <sebastien.bessiere@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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While running Linux as guest on top of phyp, we possiblly have
PE that includes single PCI device. However, we didn't return
its PCI bus correctly and it leads to failure on recovery from
EEH errors for single-dev-PE. The patch fixes the issue.
Cc: <stable@vger.kernel.org> # v3.7+
Cc: Steve Best <sbest@us.ibm.com>
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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While technically it's legal to write to PIR and have the identifier changed,
we don't implement logic to do so because we simply expose vcpu_id to the guest.
So instead, let's ignore writes to PIR. This ensures that we don't inject faults
into the guest for something the guest is allowed to do. While at it, we cross
our fingers hoping that it also doesn't mind that we broke its PIR read values.
Signed-off-by: Alexander Graf <agraf@suse.de>
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At present, if the guest creates a valid SLB (segment lookaside buffer)
entry with the slbmte instruction, then invalidates it with the slbie
instruction, then reads the entry with the slbmfee/slbmfev instructions,
the result of the slbmfee will have the valid bit set, even though the
entry is not actually considered valid by the host. This is confusing,
if not worse. This fixes it by zeroing out the orige and origv fields
of the SLB entry structure when the entry is invalidated.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
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With this, the guest can use 1TB segments as well as 256MB segments.
Since we now have the situation where a single emulated guest segment
could correspond to multiple shadow segments (as the shadow segments
are still 256MB segments), this adds a new kvmppc_mmu_flush_segment()
to scan for all shadow segments that need to be removed.
This restructures the guest HPT (hashed page table) lookup code to
use the correct hashing and matching functions for HPTEs within a
1TB segment. We use the standard hpt_hash() function instead of
open-coding the hash calculation, and we use HPTE_V_COMPARE() with
an AVPN value that has the B (segment size) field included. The
calculation of avpn is done a little earlier since it doesn't change
in the loop starting at the do_second label.
The computation in kvmppc_mmu_book3s_64_esid_to_vsid() changes so that
it returns a 256MB VSID even if the guest SLB entry is a 1TB entry.
This is because the users of this function are creating 256MB SLB
entries. We set a new VSID_1T flag so that entries created from 1T
segments don't collide with entries from 256MB segments.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
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The loop in kvmppc_mmu_book3s_64_xlate() that looks up a translation
in the guest hashed page table (HPT) keeps going if it finds an
HPTE that matches but doesn't allow access. This is incorrect; it
is different from what the hardware does, and there should never be
more than one matching HPTE anyway. This fixes it to stop when any
matching HPTE is found.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
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On entering a PR KVM guest, we invalidate the whole SLB before loading
up the guest entries. We do this using an slbia instruction, which
invalidates all entries except entry 0, followed by an slbie to
invalidate entry 0. However, the slbie turns out to be ineffective
in some circumstances (specifically when the host linear mapping uses
64k pages) because of errors in computing the parameter to the slbie.
The result is that the guest kernel hangs very early in boot because
it takes a DSI the first time it tries to access kernel data using
a linear mapping address in real mode.
Currently we construct bits 36 - 43 (big-endian numbering) of the slbie
parameter by taking bits 56 - 63 of the SLB VSID doubleword. These bits
for the tlbie are C (class, 1 bit), B (segment size, 2 bits) and 5
reserved bits. For the SLB VSID doubleword these are C (class, 1 bit),
reserved (1 bit), LP (large page size, 2 bits), and 4 reserved bits.
Thus we are not setting the B field correctly, and when LP = 01 as
it is for 64k pages, we are setting a reserved bit.
Rather than add more instructions to calculate the slbie parameter
correctly, this takes a simpler approach, which is to set entry 0 to
zeroes explicitly. Normally slbmte should not be used to invalidate
an entry, since it doesn't invalidate the ERATs, but it is OK to use
it to invalidate an entry if it is immediately followed by slbia,
which does invalidate the ERATs. (This has been confirmed with the
Power architects.) This approach takes fewer instructions and will
work whatever the contents of entry 0.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
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This makes sure the calculation of the proto-VSIDs used by PR KVM
is done with 64-bit arithmetic. Since vcpu3s->context_id[] is int,
when we do vcpu3s->context_id[0] << ESID_BITS the shift will be done
with 32-bit instructions, possibly leading to significant bits
getting lost, as the context id can be up to 524283 and ESID_BITS is
18. To fix this we cast the context id to u64 before shifting.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
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Availablity of the doorbell_exception function is guarded by
CONFIG_PPC_DOORBELL. Use the same define to guard our caller
of it.
Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
[agraf: improve patch description]
Signed-off-by: Alexander Graf <agraf@suse.de>
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git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc fixes from Ben Herrenschmidt:
"We discovered some breakage in our "EEH" (PCI Error Handling) code
while doing error injection, due to a couple of regressions. One of
them is due to a patch (37f02195bee9 "powerpc/pci: fix PCI-e devices
rescan issue on powerpc platform") that, in hindsight, I shouldn't
have merged considering that it caused more problems than it solved.
Please pull those two fixes. One for a simple EEH address cache
initialization issue. The other one is a patch from Guenter that I
had originally planned to put in 3.11 but which happens to also fix
that other regression (a kernel oops during EEH error handling and
possibly hotplug).
With those two, the couple of test machines I've hammered with error
injection are remaining up now. EEH appears to still fail to recover
on some devices, so there is another problem that Gavin is looking
into but at least it's no longer crashing the kernel."
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc/pci: Improve device hotplug initialization
powerpc/eeh: Add eeh_dev to the cache during boot
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Due to recent changes and expecations of proper cpu bindings, there are
now cases for many of the in-tree devicetrees where a WARN() will hit
on boot due to badly formatted /cpus nodes.
Downgrade this to a pr_warn() to be less alarmist, since it's not a
new problem.
Tested on Arndale, Cubox, Seaboard and Panda ES. Panda hits the WARN
without this, the others do not.
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Commit 37f02195b (powerpc/pci: fix PCI-e devices rescan issue on powerpc
platform) fixes a problem with interrupt and DMA initialization on hot
plugged devices. With this commit, interrupt and DMA initialization for
hot plugged devices is handled in the pci device enable function.
This approach has a couple of drawbacks. First, it creates two code paths
for device initialization, one for hot plugged devices and another for devices
known during the initial PCI scan. Second, the initialization code for hot
plugged devices is only called when the device is enabled, ie typically
in the probe function. Also, the platform specific setup code is called each
time pci_enable_device() is called, not only once during device discovery,
meaning it is actually called multiple times, once for devices discovered
during the initial scan and again each time a driver is re-loaded.
The visible result is that interrupt pins are only assigned to hot plugged
devices when the device driver is loaded. Effectively this changes the PCI
probe API, since pci_dev->irq and the device's dma configuration will now
only be valid after pci_enable() was called at least once. A more subtle
change is that platform specific PCI device setup is moved from device
discovery into the driver's probe function, more specifically into the
pci_enable_device() call.
To fix the inconsistencies, add new function pcibios_add_device.
Call pcibios_setup_device from pcibios_setup_bus_devices if device setup
is not complete, and from pcibios_add_device if bus setup is complete.
With this change, device setup code is moved back into device initialization,
and called exactly once for both static and hot plugged devices.
[ This also fixes a regression introduced by the above patch which
causes dev->irq to be overwritten under some cirumstances after
MSIs have been enabled for the device which leads to crashes due
to the MSI core "hijacking" dev->irq to store the base MSI number
and not the LSI. --BenH
]
Cc: Yuanquan Chen <Yuanquan.Chen@freescale.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Hiroo Matsumoto <matsumoto.hiroo@jp.fujitsu.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Conflicts:
arch/arm/Makefile
arch/arm/include/asm/glue-proc.h
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For LPAE, do_sect_fault used to be invoked as the second level access
flag handler. When transparent huge pages were introduced for LPAE,
do_page_fault was used instead.
Unfortunately, do_sect_fault remains defined but not used for LPAE code
resulting in a compile warning.
This patch surrounds do_sect_fault with #ifndef CONFIG_ARM_LPAE to fix
this warning.
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Starting up the C compiler can be a slow operation on some systems.
Though these calls don't individually take a lot of time, they add up.
Rearrange the ARM Makefile a bit to avoid extra calls to the compiler
when they can be easily avoided.
When running with the Chrome OS ARM cross compiler
"armv7a-cros-linux-gnueabi-", this shaved .55 seconds (from 5.31
seconds to 4.76 seconds) off an incremental build of the kernel:
time make -j32 ARCH=arm CROSS_COMPILE=armv7a-cros-linux-gnueabi-
Thanks to Mike Frysinger for the clean trick to make this work.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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The %.dtb dependency is specified to depend on the PHONY "scripts".
That means that it'll build every time even if the underlying dtb file
hasn't been touched. Use an order-only prerequisites to fix this.
Also mark "dtbs" as PHONY for correctness.
This was broken in (70b0476 ARM: 7513/1: Make sure dtc is built before
running it).
Reported-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Olof Johansson <olof@lixom.net>
Reviewed-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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now...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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new helpers - dir_emit_dot(file, ctx, dentry), dir_emit_dotdot(file, ctx),
dir_emit_dots(file, ctx).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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New method - ->iterate(file, ctx). That's the replacement for ->readdir();
it takes callback from ctx->actor, uses ctx->pos instead of file->f_pos and
calls dir_emit(ctx, ...) instead of filldir(data, ...). It does *not*
update file->f_pos (or look at it, for that matter); iterate_dir() does the
update.
Note that dir_emit() takes the offset from ctx->pos (and eventually
filldir_t will lose that argument).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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iterate_dir(): new helper, replacing vfs_readdir().
struct dir_context: contains the readdir callback (and will get more stuff
in it), embedded into whatever data that callback wants to deal with;
eventually, we'll be passing it to ->readdir() replacement instead of
(data,filldir) pair.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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io_remap_pfn_range() does all we need
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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io_remap_pfn_range() sets it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Adjustments to Xen's persistent clock via update_persistent_clock()
don't actually persist, as the Xen wallclock is a software only clock
and modifications to it do not modify the underlying CMOS RTC.
The x86_platform.set_wallclock hook is there to keep the hardware RTC
synchronized. On a guest this is pointless.
On Dom0 we can use the native implementaion which actually updates the
hardware RTC, but we still need to keep the software emulation of RTC
for the guests up to date. The subscription to the pvclock_notifier
allows us to emulate this easily. The notifier is called at every tick
and when the clock was set.
Right now we only use that notifier when the clock was set, but due to
the fact that it is called periodically from the timekeeping update
code, we can utilize it to emulate the NTP driven drift compensation
of update_persistant_clock() for the Xen wall (software) clock.
Add a 11 minutes periodic update to the pvclock_gtod notifier callback
to achieve that. The static variable 'next' which maintains that 11
minutes update cycle is protected by the core code serialization so
there is no need to add a Xen specific serialization mechanism.
[ tglx: Massaged changelog and added a few comments ]
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: <xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/1372329348-20841-6-git-send-email-david.vrabel@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Currently the Xen wallclock is only updated every 11 minutes if NTP is
synchronized to its clock source (using the sync_cmos_clock() work).
If a guest is started before NTP is synchronized it may see an
incorrect wallclock time.
Use the pvclock_gtod notifier chain to receive a notification when the
system time has changed and update the wallclock to match.
This chain is called on every timer tick and we want to avoid an extra
(expensive) hypercall on every tick. Because dom0 has historically
never provided a very accurate wallclock and guests do not expect one,
we can do this simply: the wallclock is only updated if the clock was
set.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: <xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/1372329348-20841-5-git-send-email-david.vrabel@citrix.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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... because the "clock_event_device framework" already accounts for idle
time through the "event_handler" function pointer in
xen_timer_interrupt().
The patch is intended as the completion of [1]. It should fix the double
idle times seen in PV guests' /proc/stat [2]. It should be orthogonal to
stolen time accounting (the removed code seems to be isolated).
The approach may be completely misguided.
[1] https://lkml.org/lkml/2011/10/6/10
[2] http://lists.xensource.com/archives/html/xen-devel/2010-08/msg01068.html
John took the time to retest this patch on top of v3.10 and reported:
"idle time is correctly incremented for pv and hvm for the normal
case, nohz=off and nohz=idle." so lets put this patch in.
CC: stable@vger.kernel.org
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: John Haxby <john.haxby@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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This fixes the problem that "init=" options may not be passed to kernel
correctly.
parse_mem_cmdline() of mn10300 arch gets rid of "mem=" string from
redboot_command_line. Then init_setup() parses the "init=" options from
static_command_line, which is a copy of redboot_command_line, and keeps
the pointer to the init options in execute_command variable.
Since the commit 026cee0 upstream (params: <level>_initcall-like kernel
parameters), static_command_line becomes overwritten by saved_command_line at
do_initcall_level(). Notice that saved_command_line is a command line
which includes "mem=" string.
As a result, execute_command may point to weird string by the length of
"mem=" parameter.
I noticed this problem when using the command line like this:
mem=128M console=ttyS0,115200 init=/bin/sh
Here is the processing flow of command line parameters.
start_kernel()
setup_arch(&command_line)
parse_mem_cmdline(cmdline_p)
* strcpy(boot_command_line, redboot_command_line);
* Remove "mem=xxx" from redboot_command_line.
* *cmdline_p = redboot_command_line;
setup_command_line(command_line) <-- command_line is redboot_command_line
* strcpy(saved_command_line, boot_command_line)
* strcpy(static_command_line, command_line)
parse_early_param()
strlcpy(tmp_cmdline, boot_command_line, COMMAND_LINE_SIZE);
parse_early_options(tmp_cmdline);
parse_args("early options", cmdline, NULL, 0, 0, 0, do_early_param);
parse_args("Booting ..", static_command_line, ...);
init_setup() <-- save the pointer in execute_command
rest_init()
kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
At this point, execute_command points to "/bin/sh" string.
kernel_init()
kernel_init_freeable()
do_basic_setup()
do_initcalls()
do_initcall_level()
(*) strcpy(static_command_line, saved_command_line);
Here, execute_command gets to point to "200" string !!
Signed-off-by: David Howells <dhowells@redhat.com>
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This fixes the following compile error:
CC block/scsi_ioctl.o
block/scsi_ioctl.c: In function 'sg_scsi_ioctl':
block/scsi_ioctl.c:449: error: invalid initializer
Signed-off-by: David Howells <dhowells@redhat.com>
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__iommu_alloc_buffer wants to split pages after allocation in order to
reduce the memory footprint. This does not work well with __GFP_COMP
pages, so drop this flag before allocation
One failure example is snd_malloc_dev_pages call dma_alloc_coherent with
__GFP_COMP.
Signed-off-by: Richard Zhao <rizhao@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
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It is common for one sg to include many pages, so mark all these
pages as clean to avoid unnecessary flushing on them in
set_pte_at() or update_mmu_cache().
The patch might improve loading performance of applciation code a bit.
On the below test code to read file(~1GByte size) from usb mass storage
disk to buffer created with mmap(PROT_READ | PROT_EXEC) on
Pandaboard, average ~1% improvement can be observed with the patch on
10 times test.
unsigned int sum = 0;
static unsigned long tv_diff(struct timeval *tv1, struct timeval *tv2)
{
return (tv2->tv_sec - tv1->tv_sec) * 1000000 +
(tv2->tv_usec - tv1->tv_usec);
}
int main(int argc, char *argv[])
{
char *mbuffer;
int fd;
int i;
unsigned long page_size, size;
struct stat stat;
struct timeval t1, t2;
page_size = getpagesize();
fd = open(argv[1], O_RDONLY);
assert(fd >= 0);
fstat(fd, &stat);
size = stat.st_size;
printf("%s: file %s, file size %lu, page size %lu\n", argv[0],
read_filename, size, page_size);
gettimeofday(&t1, NULL);
mbuffer = mmap(NULL, size, PROT_READ | PROT_EXEC, MAP_SHARED, fd, 0);
for (i = 0 ; i < size ; i += page_size)
sum += mbuffer[i];
munmap(mbuffer, page_size);
gettimeofday(&t2, NULL);
printf("\tread mmaped time: %luus\n", tv_diff(&t1, &t2));
close(fd);
}
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
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