Commit description is copied from the original post of this bug:
http://comments.gmane.org/gmane.linux.kernel.mm/135349
Kernels after v3.9 use kmalloc_size(INDEX_NODE + 1) to get the next
larger cache size than the size index INDEX_NODE mapping. In kernels
3.9 and earlier we used malloc_sizes[INDEX_L3 + 1].cs_size.
However, sometimes we can't get the right output we expected via
kmalloc_size(INDEX_NODE + 1), causing a BUG().
The mapping table in the latest kernel is like:
index = {0, 1, 2 , 3, 4, 5, 6, n}
size = {0, 96, 192, 8, 16, 32, 64, 2^n}
The mapping table before 3.10 is like this:
index = {0 , 1 , 2, 3, 4 , 5 , 6, n}
size = {32, 64, 96, 128, 192, 256, 512, 2^(n+3)}
The problem on my mips64 machine is as follows:
(1) When configured DEBUG_SLAB && DEBUG_PAGEALLOC && DEBUG_LOCK_ALLOC
&& DEBUG_SPINLOCK, the sizeof(struct kmem_cache_node) will be "150",
and the macro INDEX_NODE turns out to be "2": #define INDEX_NODE
kmalloc_index(sizeof(struct kmem_cache_node))
(2) Then the result of kmalloc_size(INDEX_NODE + 1) is 8.
(3) Then "if(size >= kmalloc_size(INDEX_NODE + 1)" will lead to "size
= PAGE_SIZE".
(4) Then "if ((size >= (PAGE_SIZE >> 3))" test will be satisfied and
"flags |= CFLGS_OFF_SLAB" will be covered.
(5) if (flags & CFLGS_OFF_SLAB)" test will be satisfied and will go to
"cachep->slabp_cache = kmalloc_slab(slab_size, 0u)", and the result
here may be NULL while kernel bootup.
(6) Finally,"BUG_ON(ZERO_OR_NULL_PTR(cachep->slabp_cache));" causes the
BUG info as the following shows (may be only mips64 has this problem):
This patch fixes the problem of kmalloc_size(INDEX_NODE + 1) and removes
the BUG by adding 'size >= 256' check to guarantee that all necessary
small sized slabs are initialized regardless sequence of slab size in
mapping table.
Fixes: e33660165c ("slab: Use common kmalloc_index/kmalloc_size...")
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reported-by: Liuhailong <liu.hailong6@zte.com.cn>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As include/uapi/linux/userfaultfd.h is a user visible header file, it
should not include kernel-exclusive header files.
So trying to build the userfaultfd test program from the selftests
directory fails, since it contains a reference to linux/compiler.h. As
it turns out, that header is not really needed there, so we can simply
remove it to fix that issue.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
a few i915 fixes for v4.3.
* tag 'drm-intel-fixes-2015-10-01' of git://anongit.freedesktop.org/drm-intel:
drm/i915: Call non-locking version of drm_kms_helper_poll_enable(), v2
drm: Add a non-locking version of drm_kms_helper_poll_enable(), v2
drm/i915: Consider HW CSB write pointer before resetting the sw read pointer
drm/i915/skl: Don't call intel_prepare_ddi when encoder list isn't yet initialized.
A single commit to fix a command submission hang regression.
Pull request of 2015-10-01
* tag 'vmwgfx-fixes-4.3-151001' of git://people.freedesktop.org/~thomash/linux:
drm/vmwgfx: Fix a command submission hang regression
This pull request includes regression fixups, build warnings, and
trivial cleanups which mostly remove some codes not used anymore.
* 'exynos-drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/daeinki/drm-exynos:
drm/exynos: Staticize local function in exynos_drm_gem.c
drm/exynos: fimd: actually disable dp clock
drm/exynos: dp: remove suspend/resume functions
drm/exynos: remove unused mode_fixup() code
drm/exynos: remove decon_mode_fixup()
drm/exynos: remove fimd_mode_fixup()
drm/exynos: rotator: Clock control is unused if !PM
drm/exynos: fimc: Clock control is unused if !PM
drm/exynos: Suspend/resume is unused if !PM
drm/exynos: create a fake mmap offset with gem creation
drm/exynos: remove call to drm_gem_free_mmap_offset()
drm/exynos: Remove useless EXPORT_SYMBOL_GPLs
drm/exynos: cleanup line feed in exynos_drm_gem_get_ioctl
drm/exynos: cleanup function calling written twice
drm/exynos: staticize exynos_drm_gem_init()
drm/exynos: remove unnecessary NULL assignment
drm/exynos: fix missed calling of drm_prime_gem_destroy()
drm/exynos: fix layering violation of address
radeon and amdgpu fixes for 4.3.
- backlight s/r fixes
- typo fix from Dan
- vm debugging fix
- remove import_gpu_mem after discussion with Daniel
* 'drm-fixes-4.3' of git://people.freedesktop.org/~agd5f/linux:
drm/amdgpu: only print meaningful VM faults
drm/amdgpu/cgs: remove import_gpu_mem
drm/amdgpu: Restore LCD backlight level on resume
drm/radeon: Restore LCD backlight level on resume (>= R5xx)
drm/amdgpu: signedness bug in amdgpu_cs_parser_init()
Pull KVM fixes from Paolo Bonzini:
"(Relatively) a lot of reverts, mostly.
Bugs have trickled in for a new feature in 4.2 (MTRR support in
guests) so I'm reverting it all; let's not make this -rc period busier
for KVM than it's been so far. This covers the four reverts from me.
The fifth patch is being reverted because Radim found a bug in the
implementation of stable scheduler clock, *but* also managed to
implement the feature entirely without hypervisor support. So instead
of fixing the hypervisor side we can remove it completely; 4.4 will
get the new implementation"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
Use WARN_ON_ONCE for missing X86_FEATURE_NRIPS
Update KVM homepage Url
Revert "KVM: SVM: use NPT page attributes"
Revert "KVM: svm: handle KVM_X86_QUIRK_CD_NW_CLEARED in svm_get_mt_mask"
Revert "KVM: SVM: Sync g_pat with guest-written PAT value"
Revert "KVM: x86: apply guest MTRR virtualization on host reserved pages"
Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock system MSR"
Pull rdma fixes from Doug Ledford:
- Fixes for mlx5 related issues
- Fixes for ipoib multicast handling
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma:
IB/ipoib: increase the max mcast backlog queue
IB/ipoib: Make sendonly multicast joins create the mcast group
IB/ipoib: Expire sendonly multicast joins
IB/mlx5: Remove pa_lkey usages
IB/mlx5: Remove support for IB_DEVICE_LOCAL_DMA_LKEY
IB/iser: Add module parameter for always register memory
xprtrdma: Replace global lkey with lkey local to PD
6910fa1 ("arm64: enable PTE type bit in the mask for pte_modify") fixes
a problem whereby a large block of PROT_NONE mapped memory is
incorrectly mapped as block descriptors when mprotect is called.
Unfortunately, a subtle bug was introduced by this fix to the THP logic.
If one mmaps a large block of memory, then faults it such that it is
collapsed into THPs; resulting calls to mprotect on this area of memory
will lead to incorrect table descriptors being written instead of block
descriptors. This is because pmd_modify calls pte_modify which is now
allowed to modify the type of the page table entry.
This patch reverts commit 6910fa16db, and
fixes the problem it was trying to address by adjusting PAGE_NONE to
represent a table entry. Thus no change in pte type is required when
moving from PROT_NONE to a different protection.
Fixes: 6910fa16db ("arm64: enable PTE type bit in the mask for pte_modify")
Cc: <stable@vger.kernel.org> # 4.0+
Cc: Feng Kan <fkan@apm.com>
Reported-by: Ganapatrao Kulkarni <Ganapatrao.Kulkarni@caviumnetworks.com>
Tested-by: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
FEXPORT also marks the symbol as code using .type symbol, @function.
Without objdump -d will output only a hexdump for code following the
affected symbols.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The cpu feature flags are not ever going to change, so warning
everytime can cause a lot of kernel log spam
(in our case more than 10GB/hour).
The warning seems to only occur when nested virtualization is
enabled, so it's probably triggered by a KVM bug. This is a
sensible and safe change anyway, and the KVM bug fix might not
be suitable for stable releases anyway.
Cc: stable@vger.kernel.org
Signed-off-by: Dirk Mueller <dmueller@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The patch f9db0d0f1b ("perf callchain: Allow disabling call graphs
per event") added an ability to enable/disable callchain recording per
event. But it had a problem when the enablement setting is changed at
'perf report' time using -g/--call-graph option.
For example, the following scenario will get a segfault.
$ perf record -ag sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.500 MB perf.data (2555 samples) ]
$ perf report -g none
perf: Segmentation fault
-------- backtrace --------
perf[0x53a98a]
/usr/lib/libc.so.6(+0x335af)[0x7f4e91df95af]
This is because callchain_param.sort() callback was not set but it
tried to call the function as it had the PERF_SAMPLE_CALLCHAIN bit.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Fixes: f9db0d0f1b ("perf callchain: Allow disabling call graphs per event")
Link: http://lkml.kernel.org/r/1443587640-24242-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The perf top uses 'dso,symbol' sort keys by default so it overlooked a
problem in task's comm resolving. When the sort key contains 'comm',
some task's comm is not shown properly. This is because the
perf_top__mmap_read_idx() checks the cpumode value improperly.
The cpumode value of non-sample events are 0 (PERF_RECORD_MISC_CPUMODE_
UNKNOWN) so the events will be ignored by the switch statement. This patch
allows it for non-sample events.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1443577526-3240-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A previous patch added a synthesized comm event for forked child process
but it missed that the event should contain area for sample_id_hdr at
the end. It worked by accident since the perf_event union contains
bigger event structs like mmap_events.
This patch fixes it by dynamically allocating event struct including
those area like in perf_event__synthesize_thread_map().
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1443577526-3240-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The old one appears to be a generic catch all page, which
is unhelpful.
Signed-off-by: Dirk Mueller <dmueller@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull UBI/UBIFS fixes from Richard Weinberger:
"This contains three bug fixes for both UBI and UBIFS"
* tag 'upstream-4.3-rc4' of git://git.infradead.org/linux-ubifs:
UBI: return ENOSPC if no enough space available
UBI: Validate data_size
UBIFS: Kill unneeded locking in ubifs_init_security
Pull key signing fixes from James Morris:
"Keyrings and modsign fixes from David Howells"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
MODSIGN: Change from CMS to PKCS#7 signing if the openssl is too old
X.509: Don't strip leading 00's from key ID when constructing key description
KEYS: Remove unnecessary header #inclusions from extract-cert.c
KEYS: Fix race between key destruction and finding a keyring by name
This reverts commit 3c2e7f7de3.
Initializing the mapping from MTRR to PAT values was reported to
fail nondeterministically, and it also caused extremely slow boot
(due to caching getting disabled---bug 103321) with assigned devices.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Reported-by: Sebastian Schuette <dracon@ewetel.net>
Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The new Properties Table feature introduced in UEFIv2.5 may
split memory regions that cover PE/COFF memory images into
separate code and data regions. Since these regions only differ
in the type (runtime code vs runtime data) and the permission
bits, but not in the memory type attributes (UC/WC/WT/WB), the
spec does not require them to be aligned to 64 KB.
Since the relative offset of PE/COFF .text and .data segments
cannot be changed on the fly, this means that we can no longer
pad out those regions to be mappable using 64 KB pages.
Unfortunately, there is no annotation in the UEFI memory map
that identifies data regions that were split off from a code
region, so we must apply this logic to all adjacent runtime
regions whose attributes only differ in the permission bits.
So instead of rounding each memory region to 64 KB alignment at
both ends, only round down regions that are not directly
preceded by another runtime region with the same type
attributes. Since the UEFI spec does not mandate that the memory
map be sorted, this means we also need to sort it first.
Note that this change will result in all EFI_MEMORY_RUNTIME
regions whose start addresses are not aligned to the OS page
size to be mapped with executable permissions (i.e., on kernels
compiled with 64 KB pages). However, since these mappings are
only active during the time that UEFI Runtime Services are being
invoked, the window for abuse is rather small.
Tested-by: Mark Salter <msalter@redhat.com>
Tested-by: Mark Rutland <mark.rutland@arm.com> [UEFI 2.4 only]
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Reviewed-by: Mark Salter <msalter@redhat.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org> # v4.0+
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1443218539-7610-3-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Beginning with UEFI v2.5 EFI_PROPERTIES_TABLE was introduced
that signals that the firmware PE/COFF loader supports splitting
code and data sections of PE/COFF images into separate EFI
memory map entries. This allows the kernel to map those regions
with strict memory protections, e.g. EFI_MEMORY_RO for code,
EFI_MEMORY_XP for data, etc.
Unfortunately, an unwritten requirement of this new feature is
that the regions need to be mapped with the same offsets
relative to each other as observed in the EFI memory map. If
this is not done crashes like this may occur,
BUG: unable to handle kernel paging request at fffffffefe6086dd
IP: [<fffffffefe6086dd>] 0xfffffffefe6086dd
Call Trace:
[<ffffffff8104c90e>] efi_call+0x7e/0x100
[<ffffffff81602091>] ? virt_efi_set_variable+0x61/0x90
[<ffffffff8104c583>] efi_delete_dummy_variable+0x63/0x70
[<ffffffff81f4e4aa>] efi_enter_virtual_mode+0x383/0x392
[<ffffffff81f37e1b>] start_kernel+0x38a/0x417
[<ffffffff81f37495>] x86_64_start_reservations+0x2a/0x2c
[<ffffffff81f37582>] x86_64_start_kernel+0xeb/0xef
Here 0xfffffffefe6086dd refers to an address the firmware
expects to be mapped but which the OS never claimed was mapped.
The issue is that included in these regions are relative
addresses to other regions which were emitted by the firmware
toolchain before the "splitting" of sections occurred at
runtime.
Needless to say, we don't satisfy this unwritten requirement on
x86_64 and instead map the EFI memory map entries in reverse
order. The above crash is almost certainly triggerable with any
kernel newer than v3.13 because that's when we rewrote the EFI
runtime region mapping code, in commit d2f7cbe7b2 ("x86/efi:
Runtime services virtual mapping"). For kernel versions before
v3.13 things may work by pure luck depending on the
fragmentation of the kernel virtual address space at the time we
map the EFI regions.
Instead of mapping the EFI memory map entries in reverse order,
where entry N has a higher virtual address than entry N+1, map
them in the same order as they appear in the EFI memory map to
preserve this relative offset between regions.
This patch has been kept as small as possible with the intention
that it should be applied aggressively to stable and
distribution kernels. It is very much a bugfix rather than
support for a new feature, since when EFI_PROPERTIES_TABLE is
enabled we must map things as outlined above to even boot - we
have no way of asking the firmware not to split the code/data
regions.
In fact, this patch doesn't even make use of the more strict
memory protections available in UEFI v2.5. That will come later.
Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Cc: <stable@vger.kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chun-Yi <jlee@suse.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: James Bottomley <JBottomley@Odin.com>
Cc: Lee, Chun-Yi <jlee@suse.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1443218539-7610-2-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Per-IRQ directories in procfs are created only when a handler is first
added to the irqdesc, not when the irqdesc is created. In the case of
a shared IRQ, multiple tasks can race to create a directory. This
race condition seems to have been present forever, but is easier to
hit with async probing.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Link: http://lkml.kernel.org/r/1443266636.2004.2.camel@decadent.org.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fix this warning:
arch/s390/configs/performance_defconfig:380:warning: symbol value 'm' invalid for SCSI_DH
Introduced via 086b91d052
(scsi_dh: integrate into the core SCSI code)
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
And replace the blk_mq_tag_busy_iter with it - the driver use has been
replaced with a new helper a while ago, and internal to the block we
only need the new version.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
blk_mq_complete_request may be a no-op if the request has already
been completed by others means (e.g. a timeout or cancellation), but
currently drivers have to set rq->errors before calling
blk_mq_complete_request, which might leave us with the wrong error value.
Add an error parameter to blk_mq_complete_request so that we can
defer setting rq->errors until we known we won the race to complete the
request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull perf/core improvements and fixes:
User visible changes:
- By default use the most precise "cycles" hw counter available, i.e.
when the user doesn't specify any event, it will try using cycles:ppp,
cycles:pp, etc. (Arnaldo Carvalho de Melo)
- Remove blank lines, headers when piping output in 'perf list', so that it can
be sanely used with 'wc -l', etc. (Arnaldo Carvalho de Melo)
- Amend documentation about max_stack and synthesized callchains. (Adrian Hunter)
- Fix 'perf probe -l' for probes added to kernel module functions. (Masami Hiramatsu)
Build fixes:
- Fix shadowed declarations that break the build on older distros. (Jiri Olsa)
- Fix build break on powerpc due to sample_reg_masks. (Sukadev Bhattiprolu)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The exynos_drm_gem_mmap_buffer() is not used outside so make it static.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
This patch removes unnecessary pm suspend/resume functions.
All kms sub drivers will be controlled by top of Exynos drm driver
and connector dpms so these sub drivers shouldn't have their own
pm interfaces.
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
A very tiny temporal window exists in the residue calculation where :
- upon entering residue calculation, the transfer is ongoing
- when reading the current transfer pointer, it just changed to
the "finisher/linker" descriptor
In this case, the residue returned is the whole transfer length instead
of 0. Fix it.
This appears almost in one extreme case, where the driver is used
by older clients which inquire for residue in interrupt context, such
as the smsc91x ethernet driver, in a tight loop :
interrupt_handler()
dmaengine_submit()
do {
dmaengine_tx_status()
} while (residue > 0 || status != DMA_ERROR)
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
A very small number of devices don't use the flow control offered by
requestor lines. In these specific cases, the pxa dma driver should be
aware of that and not try to use a requestor line.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
When putting back a descriptor to the free descs list, some fields are
not set to 0, it can cause bugs if someone uses it without having this
in mind.
Descriptor are not put back one by one so it is easier to clean
descriptors when we request them.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: stable@vger.kernel.org #4.2
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
The addressing mode we were using was not only incrementing the address at
each microblock, but also at each data boundary, which was severely slowing
the transfer, without any benefit since we were not using the data stride.
Switch to the micro block increment only in order to get back to an
acceptable performance level.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: 6007ccb577 ("dmaengine: xdmac: Add interleaved transfer support")
Cc: stable@vger.kernel.org #4.2
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
If the user doesn't specify any event, try the most precise "cycles"
available, i.e. start by "cycles:ppp" and go on removing "p" till it
works.
E.g.
$ perf record usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.017 MB perf.data (11 samples) ]
$ perf evlist
cycles:pp
$ perf evlist -v
cycles:pp: size: 112, { sample_period, sample_freq }: 4000, sample_type:
IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1,
enable_on_exec: 1, task: 1, precise_ip: 2, sample_id_all: 1,
exclude_guest: 1, mmap2: 1, comm_exec: 1
$ grep 'model name' /proc/cpuinfo | head -1
model name : Intel(R) Core(TM) i7-3667U CPU @ 2.00GHz
$
When 'cycles' appears explicitely is specified this will not be tried,
i.e. the user has full control of the level of precision to be used:
$ perf record -e cycles usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.016 MB perf.data (9 samples) ]
$ perf evlist
cycles
$ perf evlist -v
cycles: size: 112, { sample_period, sample_freq }: 4000, sample_type:
IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1,
enable_on_exec: 1, task: 1, sample_id_all: 1, exclude_guest: 1, mmap2:
1, comm_exec: 1
$
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chandler Carruth <chandlerc@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://www.youtube.com/watch?v=nXaxk27zwlk
Link: http://lkml.kernel.org/n/tip-b1ywebmt22pi78vjxau01wth@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf probe shows more precisely message when it finds given
%return target function is inlined.
Without this fix:
----
# ./perf probe -V getname_flags%return
Return probe must be on the head of a real function.
Debuginfo analysis failed.
Error: Failed to show vars.
----
With this fix:
----
# ./perf probe -V getname_flags%return
Failed to find "getname_flags%return",
because getname_flags is an inlined function and has no return point.
Debuginfo analysis failed.
Error: Failed to show vars.
----
Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20150930164137.3733.55055.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
