Allow drivers that use the nvmem API to read data stored on MTD devices.
For this the mtd devices are registered as read-only NVMEM providers.
We don't support device tree systems for now.
Signed-off-by: Alban Bedel <albeu@free.fr>
[Bartosz:
- include linux/nvmem-provider.h
- set the name of the nvmem provider
- set no_of_node to true in nvmem_config
- don't check the return value of nvmem_unregister() - it cannot fail
- tweaked the commit message]
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We want to add nvmem support for MTD. TI DaVinci is the first platform
that will be using it, but only in non-DT mode. In order not to
introduce any new interface to supporting of which we would have to
commit - add a new config option that tells nvmem not to use the DT
node of the parent device.
This way we won't be creating nvmem devices corresponding with MTD
partitions defined in device tree. By default MTD will set this new
field to true.
Once a set of bindings for MTD nvmem cells is agreed upon, we'll be
able to remove this option.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since we put static variable to a header file it's copied to each module
that includes the header. But not all of them are actually using it.
Move nvmem_type_str array to its only user to make a compiler happy:
In file included from include/linux/rtc.h:18,
from drivers/rtc/rtc-proc.c:15:
include/linux/nvmem-provider.h:29:27: warning: 'nvmem_type_str'
defined but not used [-Wunused-const-variable=]
static const char * const nvmem_type_str[] = {
^~~~~~~~~~~~~~
Suggested-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Suggested-by: Joe Perches <joe@perches.com>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Get and enable the peripheral clock required by the efuse device.
The driver has been handle to work without it so far because the
clock was left enabled by default but it won't be the case soon.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The efuse found in gx SoC requires a peripheral clock to properly operate.
We have been able to work without it until now because the clock was on by
default, and left on by the CCF. Soon, it will not be the case anymore, so
the device needs to claim the clock it needs
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a type attribute so userspace is able to know how the data is stored as
this can help taking the correct decision when selecting which device to
use. This will also help program display the proper warnings when burning
fuses for example.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When dumping out binder transactions via a debug node,
the output is too verbose if a process has many nodes.
Change the output for transaction dumps to only display
nodes with pending async transactions.
Signed-off-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We already have the DEFINE_SHOW_ATTRIBUTE.There is no need to define
such a macro,so remove GENWQE_DEBUGFS_RO.Also use DEFINE_SHOW_ATTRIBUTE
to simplify some code.
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The > comparison should be >= to prevent reading beyond the end of the
func->template[] array.
(The func->template array is allocated in vexpress_syscfg_regmap_init()
and it has func->num_templates elements.)
Fixes: 974cc7b934 ("mfd: vexpress: Define the device as MFD cells")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After finding a "firmware" dt node stratix10 tries to match it's
compatible string with it. To do so it's calling of_find_matching_node()
which already takes care of decreasing the refcount on the "firmware"
node. We are then incorrectly decreasing the refcount on that node
again.
This patch removes the unwarranted call to of_node_put().
Fixes: 7ca5ce8965 ("firmware: add Intel Stratix10 service layer driver")
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch deals with the release of the CLAIM tag when the ETM is
operated from perf. Otherwise the tag is left asserted and subsequent
requests to use the device fail.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch moves access to the CLAIM tag so that no modification to the HW
happens before and after the CLAIM operation has been carried.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch rectifies the sequence of events in function
tmc_etb_disable_hw() by disabling the HW first and then releasing the
CLAIM tag. Otherwise we could be corrupting the configuration done by an
external agent that would have claimed the device after we have released
it.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Following in the footstep of what was done for other CoreSight devices,
add CLAIM tag support to ETB10 in order to synchronise access to the
HW between the kernel and an external agent.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull ARM SoC fixes from Olof Johansson:
"Volume is a little higher than usual due to a set of gpio fixes for
Davinci platforms that's been around a while, still seemed appropriate
to not hold off until next merge window.
Besides that it's the usual mix of minor fixes, mostly corrections of
small stuff in device trees.
Major stability-related one is the removal of a regulator from DT on
Rock960, since DVFS caused undervoltage. I expect it'll be restored
once they figure out the underlying issue"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (28 commits)
MAINTAINERS: Remove unused Qualcomm SoC mailing list
ARM: davinci: dm644x: set the GPIO base to 0
ARM: davinci: da830: set the GPIO base to 0
ARM: davinci: dm355: set the GPIO base to 0
ARM: davinci: dm646x: set the GPIO base to 0
ARM: davinci: dm365: set the GPIO base to 0
ARM: davinci: da850: set the GPIO base to 0
gpio: davinci: restore a way to manually specify the GPIO base
ARM: davinci: dm644x: define gpio interrupts as separate resources
ARM: davinci: dm355: define gpio interrupts as separate resources
ARM: davinci: dm646x: define gpio interrupts as separate resources
ARM: davinci: dm365: define gpio interrupts as separate resources
ARM: davinci: da8xx: define gpio interrupts as separate resources
ARM: dts: at91: sama5d2: use the divided clock for SMC
ARM: dts: imx51-zii-rdu1: Remove EEPROM node
ARM: dts: rockchip: Remove @0 from the veyron memory node
arm64: dts: rockchip: Fix PCIe reset polarity for rk3399-puma-haikou.
arm64: dts: qcom: msm8998: Reserve gpio ranges on MTP
arm64: dts: sdm845-mtp: Reserve reserved gpios
arm64: dts: ti: k3-am654: Fix wakeup_uart reg address
...
Pull xen fixes from Juergen Gross:
- A revert of a previous commit as it is no longer necessary and has
shown to cause problems in some memory hotplug cases.
- Some small fixes and a minor cleanup.
- A patch for adding better diagnostic data in a very rare failure
case.
* tag 'for-linus-4.20a-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
pvcalls-front: fixes incorrect error handling
Revert "xen/balloon: Mark unallocated host memory as UNUSABLE"
xen: xlate_mmu: add missing header to fix 'W=1' warning
xen/x86: add diagnostic printout to xen_mc_flush() in case of error
x86/xen: cleanup includes in arch/x86/xen/spinlock.c
Pull dmaengine fixes from Vinod Koul:
"This contains two fixes to at_hdmac which fixes long standing bus
reported recently on serial transfers causing memory leak. These fixes
were done by Richard Genoud"
* tag 'dmaengine-fix-4.20-rc5' of git://git.infradead.org/users/vkoul/slave-dma:
dmaengine: at_hdmac: fix module unloading
dmaengine: at_hdmac: fix memory leak in at_dma_xlate()
Pull STIBP fallout fixes from Thomas Gleixner:
"The performance destruction department finally got it's act together
and came up with a cure for the STIPB regression:
- Provide a command line option to control the spectre v2 user space
mitigations. Default is either seccomp or prctl (if seccomp is
disabled in Kconfig). prctl allows mitigation opt-in, seccomp
enables the migitation for sandboxed processes.
- Rework the code to handle the conditional STIBP/IBPB control and
remove the now unused ptrace_may_access_sched() optimization
attempt
- Disable STIBP automatically when SMT is disabled
- Optimize the switch_to() logic to avoid MSR writes and invocations
of __switch_to_xtra().
- Make the asynchronous speculation TIF updates synchronous to
prevent stale mitigation state.
As a general cleanup this also makes retpoline directly depend on
compiler support and removes the 'minimal retpoline' option which just
pretended to provide some form of security while providing none"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
x86/speculation: Provide IBPB always command line options
x86/speculation: Add seccomp Spectre v2 user space protection mode
x86/speculation: Enable prctl mode for spectre_v2_user
x86/speculation: Add prctl() control for indirect branch speculation
x86/speculation: Prepare arch_smt_update() for PRCTL mode
x86/speculation: Prevent stale SPEC_CTRL msr content
x86/speculation: Split out TIF update
ptrace: Remove unused ptrace_may_access_sched() and MODE_IBRS
x86/speculation: Prepare for conditional IBPB in switch_mm()
x86/speculation: Avoid __switch_to_xtra() calls
x86/process: Consolidate and simplify switch_to_xtra() code
x86/speculation: Prepare for per task indirect branch speculation control
x86/speculation: Add command line control for indirect branch speculation
x86/speculation: Unify conditional spectre v2 print functions
x86/speculataion: Mark command line parser data __initdata
x86/speculation: Mark string arrays const correctly
x86/speculation: Reorder the spec_v2 code
x86/l1tf: Show actual SMT state
x86/speculation: Rework SMT state change
sched/smt: Expose sched_smt_present static key
...
Pull block layer fixes from Jens Axboe:
- Single range elevator discard merge fix, that caused crashes (Ming)
- Fix for a regression in O_DIRECT, where we could potentially lose the
error value (Maximilian Heyne)
- NVMe pull request from Christoph, with little fixes all over the map
for NVMe.
* tag 'for-linus-20181201' of git://git.kernel.dk/linux-block:
block: fix single range discard merge
nvme-rdma: fix double freeing of async event data
nvme: flush namespace scanning work just before removing namespaces
nvme: warn when finding multi-port subsystems without multipathing enabled
fs: fix lost error code in dio_complete
nvme-pci: fix surprise removal
nvme-fc: initialize nvme_req(rq)->ctrl after calling __nvme_fc_init_request()
nvme: Free ctrl device name on init failure
Pull PCI fixes from Bjorn Helgaas:
- Fix a link speed checking interface that broke PCIe gen3 cards in
gen1 slots (Mikulas Patocka)
- Fix an imx6 link training error (Trent Piepho)
- Fix a layerscape outbound window accessor calling error (Hou
Zhiqiang)
- Fix a DesignWare endpoint MSI-X address calculation error (Gustavo
Pimentel)
* tag 'pci-v4.20-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: Fix incorrect value returned from pcie_get_speed_cap()
PCI: dwc: Fix MSI-X EP framework address calculation bug
PCI: layerscape: Fix wrong invocation of outbound window disable accessor
PCI: imx6: Fix link training status detection in link up check
The macros PCI_EXP_LNKCAP_SLS_*GB are values, not bit masks. We must mask
the register and compare it against them.
This fixes errors like this:
amdgpu: [powerplay] failed to send message 261 ret is 0
when a PCIe-v3 card is plugged into a PCIe-v1 slot, because the slot is
being incorrectly reported as PCIe-v3 capable.
6cf57be0f7, which appeared in v4.17, added pcie_get_speed_cap() with the
incorrect test of PCI_EXP_LNKCAP_SLS as a bitmask. 5d9a633040, which
appeared in v4.19, changed amdgpu to use pcie_get_speed_cap(), so the
amdgpu bug reports below are regressions in v4.19.
Fixes: 6cf57be0f7 ("PCI: Add pcie_get_speed_cap() to find max supported link speed")
Fixes: 5d9a633040 ("drm/amdgpu: use pcie functions for link width and speed")
Link: https://bugs.freedesktop.org/show_bug.cgi?id=108704
Link: https://bugs.freedesktop.org/show_bug.cgi?id=108778
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
[bhelgaas: update comment, remove use of PCI_EXP_LNKCAP_SLS_8_0GB and
PCI_EXP_LNKCAP_SLS_16_0GB since those should be covered by PCI_EXP_LNKCAP2,
remove test of PCI_EXP_LNKCAP for zero, since that register is required]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org # v4.17+
Merge misc fixes from Andrew Morton:
"31 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (31 commits)
ocfs2: fix potential use after free
mm/khugepaged: fix the xas_create_range() error path
mm/khugepaged: collapse_shmem() do not crash on Compound
mm/khugepaged: collapse_shmem() without freezing new_page
mm/khugepaged: minor reorderings in collapse_shmem()
mm/khugepaged: collapse_shmem() remember to clear holes
mm/khugepaged: fix crashes due to misaccounted holes
mm/khugepaged: collapse_shmem() stop if punched or truncated
mm/huge_memory: fix lockdep complaint on 32-bit i_size_read()
mm/huge_memory: splitting set mapping+index before unfreeze
mm/huge_memory: rename freeze_page() to unmap_page()
initramfs: clean old path before creating a hardlink
kernel/kcov.c: mark funcs in __sanitizer_cov_trace_pc() as notrace
psi: make disabling/enabling easier for vendor kernels
proc: fixup map_files test on arm
debugobjects: avoid recursive calls with kmemleak
userfaultfd: shmem: UFFDIO_COPY: set the page dirty if VM_WRITE is not set
userfaultfd: shmem: add i_size checks
userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas
userfaultfd: shmem: allocate anonymous memory for MAP_PRIVATE shmem
...
Pull few more MIPS fixes from Paul Burton:
- Fix mips_get_syscall_arg() to operate on the task specified when
detecting o32 tasks running on MIPS64 kernels.
- Fix some incorrect GPIO pin muxing for the MT7620 SoC.
- Update the linux-mips mailing list address.
* tag 'mips_fixes_4.20_4' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
MAINTAINERS: Update linux-mips mailing list address
MIPS: ralink: Fix mt7620 nd_sd pinmux
mips: fix mips_get_syscall_arg o32 check
Pull stackleak plugin fix from Kees Cook:
"Fix crash by not allowing kprobing of stackleak_erase() (Alexander
Popov)"
* tag 'gcc-plugins-v4.20-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
stackleak: Disable function tracing and kprobes for stackleak_erase()
Pull fscache and cachefiles fixes from David Howells:
"Misc fixes:
- Fix an assertion failure at fs/cachefiles/xattr.c:138 caused by a
race between a cache object lookup failing and someone attempting
to reenable that object, thereby triggering an update of the
object's attributes.
- Fix an assertion failure at fs/fscache/operation.c:449 caused by a
split atomic subtract and atomic read that allows a race to happen.
- Fix a leak of backing pages when simultaneously reading the same
page from the same object from two or more threads.
- Fix a hang due to a race between a cache object being discarded and
the corresponding cookie being reenabled.
There are also some minor cleanups:
- Cast an enum value to a different enum type to prevent clang from
generating a warning. This shouldn't cause any sort of change in
the emitted code.
- Use ktime_get_real_seconds() instead of get_seconds(). This is just
used to uniquify a filename for an object to be placed in the
graveyard. Objects placed there are deleted by cachfilesd in
userspace immediately thereafter.
- Remove an initialised, but otherwise unused variable. This should
have been entirely optimised away anyway"
* tag 'fscache-fixes-20181130' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
fscache, cachefiles: remove redundant variable 'cache'
cachefiles: avoid deprecated get_seconds()
cachefiles: Explicitly cast enumerated type in put_object
fscache: fix race between enablement and dropping of object
cachefiles: Fix page leak in cachefiles_read_backing_file while vmscan is active
fscache: Fix race in fscache_op_complete() due to split atomic_sub & read
cachefiles: Fix an assertion failure when trying to update a failed object
khugepaged's collapse_shmem() does almost all of its work, to assemble
the huge new_page from 512 scattered old pages, with the new_page's
refcount frozen to 0 (and refcounts of all old pages so far also frozen
to 0). Including shmem_getpage() to read in any which were out on swap,
memory reclaim if necessary to allocate their intermediate pages, and
copying over all the data from old to new.
Imagine the frozen refcount as a spinlock held, but without any lock
debugging to highlight the abuse: it's not good, and under serious load
heads into lockups - speculative getters of the page are not expecting
to spin while khugepaged is rescheduled.
One can get a little further under load by hacking around elsewhere; but
fortunately, freezing the new_page turns out to have been entirely
unnecessary, with no hacks needed elsewhere.
The huge new_page lock is already held throughout, and guards all its
subpages as they are brought one by one into the page cache tree; and
anything reading the data in that page, without the lock, before it has
been marked PageUptodate, would already be in the wrong. So simply
eliminate the freezing of the new_page.
Each of the old pages remains frozen with refcount 0 after it has been
replaced by a new_page subpage in the page cache tree, until they are
all unfrozen on success or failure: just as before. They could be
unfrozen sooner, but cause no problem once no longer visible to
find_get_entry(), filemap_map_pages() and other speculative lookups.
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1811261527570.2275@eggly.anvils
Fixes: f3f0e1d215 ("khugepaged: add support of collapse for tmpfs/shmem pages")
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org> [4.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Huge tmpfs testing on a shortish file mapped into a pmd-rounded extent
hit shmem_evict_inode()'s WARN_ON(inode->i_blocks) followed by
clear_inode()'s BUG_ON(inode->i_data.nrpages) when the file was later
closed and unlinked.
khugepaged's collapse_shmem() was forgetting to update mapping->nrpages
on the rollback path, after it had added but then needs to undo some
holes.
There is indeed an irritating asymmetry between shmem_charge(), whose
callers want it to increment nrpages after successfully accounting
blocks, and shmem_uncharge(), when __delete_from_page_cache() already
decremented nrpages itself: oh well, just add a comment on that to them
both.
And shmem_recalc_inode() is supposed to be called when the accounting is
expected to be in balance (so it can deduce from imbalance that reclaim
discarded some pages): so change shmem_charge() to update nrpages
earlier (though it's rare for the difference to matter at all).
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1811261523450.2275@eggly.anvils
Fixes: 800d8c63b2 ("shmem: add huge pages support")
Fixes: f3f0e1d215 ("khugepaged: add support of collapse for tmpfs/shmem pages")
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org> [4.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Huge tmpfs stress testing has occasionally hit shmem_undo_range()'s
VM_BUG_ON_PAGE(page_to_pgoff(page) != index, page).
Move the setting of mapping and index up before the page_ref_unfreeze()
in __split_huge_page_tail() to fix this: so that a page cache lookup
cannot get a reference while the tail's mapping and index are unstable.
In fact, might as well move them up before the smp_wmb(): I don't see an
actual need for that, but if I'm missing something, this way round is
safer than the other, and no less efficient.
You might argue that VM_BUG_ON_PAGE(page_to_pgoff(page) != index, page) is
misplaced, and should be left until after the trylock_page(); but left as
is has not crashed since, and gives more stringent assurance.
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1811261516380.2275@eggly.anvils
Fixes: e9b61f1985 ("thp: reintroduce split_huge_page()")
Requires: 605ca5ede7 ("mm/huge_memory.c: reorder operations in __split_huge_page_tail()")
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org> [4.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since __sanitizer_cov_trace_pc() is marked as notrace, function calls in
__sanitizer_cov_trace_pc() shouldn't be traced either.
ftrace_graph_caller() gets called for each function that isn't marked
'notrace', like canonicalize_ip(). This is the call trace from a run:
[ 139.644550] ftrace_graph_caller+0x1c/0x24
[ 139.648352] canonicalize_ip+0x18/0x28
[ 139.652313] __sanitizer_cov_trace_pc+0x14/0x58
[ 139.656184] sched_clock+0x34/0x1e8
[ 139.659759] trace_clock_local+0x40/0x88
[ 139.663722] ftrace_push_return_trace+0x8c/0x1f0
[ 139.667767] prepare_ftrace_return+0xa8/0x100
[ 139.671709] ftrace_graph_caller+0x1c/0x24
Rework so that check_kcov_mode() and canonicalize_ip() that are called
from __sanitizer_cov_trace_pc() are also marked as notrace.
Link: http://lkml.kernel.org/r/20181128081239.18317-1-anders.roxell@linaro.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signen-off-by: Anders Roxell <anders.roxell@linaro.org>
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman reports a hackbench regression with psi that would prohibit
shipping the suse kernel with it default-enabled, but he'd still like
users to be able to opt in at little to no cost to others.
With the current combination of CONFIG_PSI and the psi_disabled bool set
from the commandline, this is a challenge. Do the following things to
make it easier:
1. Add a config option CONFIG_PSI_DEFAULT_DISABLED that allows distros
to enable CONFIG_PSI in their kernel but leave the feature disabled
unless a user requests it at boot-time.
To avoid double negatives, rename psi_disabled= to psi=.
2. Make psi_disabled a static branch to eliminate any branch costs
when the feature is disabled.
In terms of numbers before and after this patch, Mel says:
: The following is a comparision using CONFIG_PSI=n as a baseline against
: your patch and a vanilla kernel
:
: 4.20.0-rc4 4.20.0-rc4 4.20.0-rc4
: kconfigdisable-v1r1 vanilla psidisable-v1r1
: Amean 1 1.3100 ( 0.00%) 1.3923 ( -6.28%) 1.3427 ( -2.49%)
: Amean 3 3.8860 ( 0.00%) 4.1230 * -6.10%* 3.8860 ( -0.00%)
: Amean 5 6.8847 ( 0.00%) 8.0390 * -16.77%* 6.7727 ( 1.63%)
: Amean 7 9.9310 ( 0.00%) 10.8367 * -9.12%* 9.9910 ( -0.60%)
: Amean 12 16.6577 ( 0.00%) 18.2363 * -9.48%* 17.1083 ( -2.71%)
: Amean 18 26.5133 ( 0.00%) 27.8833 * -5.17%* 25.7663 ( 2.82%)
: Amean 24 34.3003 ( 0.00%) 34.6830 ( -1.12%) 32.0450 ( 6.58%)
: Amean 30 40.0063 ( 0.00%) 40.5800 ( -1.43%) 41.5087 ( -3.76%)
: Amean 32 40.1407 ( 0.00%) 41.2273 ( -2.71%) 39.9417 ( 0.50%)
:
: It's showing that the vanilla kernel takes a hit (as the bisection
: indicated it would) and that disabling PSI by default is reasonably
: close in terms of performance for this particular workload on this
: particular machine so;
Link: http://lkml.kernel.org/r/20181127165329.GA29728@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
