Move U0 link state handing to USB3 and USB2 specific functions
Note that
bus_state->resuming_ports:
bus_state->resume_done[]:
are only used for USB2, and don't need to cleared for USB3 ports
No functional changes
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Group the code where the wPortstatus and wPortChange bits
are set into one place.
No functional changes
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Mostly refactoring, with the exception that USB_PORT_STAT_L1 link state
is reported if xhci port link is in U2 AND port is powered.
Previously we did not check if the port was powered, but according to
xhci spec 4.19.1.1.6 All the 'Enabled' states, including
USB_PORT_STAT_L1 (U2), U1, U0 and U3 must have Port power bit set.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that each root hub has their own bus_state strucure the
hcd_undex() used to get the correct bus_state strucure is
no longer needed.
No functional changes
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move the bus_state structure under struct usb_hub.
We need a bus_state strucure for each roothub to keep track of suspend
related info for each port.
Instead of keeping an array of two bus_state structures right under
struct xhci, it makes more sense move them to the xhci_hub structure.
No functional changes.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It is introduced for the pre-0.96 xHC controllers, and the driver only
support HW LPM for 1.0 and later controllers.It's not actually used now
and is thought not to be used in the future any more, so just remove it.
Signed-off-by: Zeng Tao <prime.zeng@hisilicon.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The spinlock was inside the urb completion function which is only
called once per display and is then resubmitted from this function.
There was no other place where this lock was used.
Signed-off-by: Alexander Theissen <alex.theissen@me.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver does allocate a DMA address with usb_alloc_coherent but did
not set the appropriate flag to signal that transfer_dma is set to a
valid value.
Signed-off-by: Alexander Theissen <alex.theissen@me.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the controller supports SS mode, but works as HS mode, the
SOFTCONN will not be cleared automatically when clear USB3_EN
by default, this cause an issue that can't disconnect from host,
so clear SOFTCONN when clear USB3_EN when the class driver want
to disable the D+ pullup.
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the controller receives a new SETUP during SETUP data stage,
and will generate SETUPENDISR interrupt, the driver should abort
the current SETUP command and process the new one.
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix the issue: device doesn't accept LGO_U1/U2:
1. set SW_U1/U2_ACCEPT_ENABLE to eanble controller to accept LGO_U1/U2
by default;
2. enable/disable controller to initiate requests for transition into
U1/U2 by SW_U1/U2_REQUEST_ENABLE instead of SW_U1/U2_ACCEPT_ENABLE;
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Enable hardware remote wakeup from L1 automatically based on the FIFO
status, instead of manual way.
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Originally, when dr_mode is USB_DR_MODE_HOST, it didn't power down device ip,
so host ip sleep will fail at ssusb_host_disable.
Power down device ip at ssusb_host_setup.
Signed-off-by: Hsin-Yi, Wang <hsinyi@chromium.org>
Acked-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When initializing a hub we want to give a USB3 port in link training
the same debounce delay time before autosuspening the hub as already
trained, connected enabled ports.
USB3 ports won't reach the enabled state with "current connect status" and
"connect status change" bits set until the USB3 link training finishes.
Catching the port in link training (polling) and adding the debounce delay
prevents unnecessary failed attempts to autosuspend the hub.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
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>
