linux514/515-tkg: Add an alternative fsync (FUTEX_WAIT_MULTIPLE) patchset that can be enabled alongside futex_waitv to have a fallback path on Proton/wine builds using the older Fsync implementation. Thanks to Kisak for reaching out to me and sharing the ideas and patches.
This commit is contained in:
Tk-Glitch
8
PKGBUILD
8
PKGBUILD
@ -59,7 +59,7 @@ else
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fi
|
fi
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pkgname=("${pkgbase}" "${pkgbase}-headers")
|
pkgname=("${pkgbase}" "${pkgbase}-headers")
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pkgver="${_basekernel}"."${_sub}"
|
pkgver="${_basekernel}"."${_sub}"
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pkgrel=212
|
pkgrel=213
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pkgdesc='Linux-tkg'
|
pkgdesc='Linux-tkg'
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arch=('x86_64') # no i686 in here
|
arch=('x86_64') # no i686 in here
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url="http://www.kernel.org/"
|
url="http://www.kernel.org/"
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@ -561,6 +561,7 @@ case $_basever in
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0005-glitched-pds.patch
|
0005-glitched-pds.patch
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||||||
0006-add-acs-overrides_iommu.patch
|
0006-add-acs-overrides_iommu.patch
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0007-v5.14-fsync.patch
|
0007-v5.14-fsync.patch
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|
0007-v5.14-fsync-waitvcompat.patch
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0007-v5.14-futex2_interface.patch
|
0007-v5.14-futex2_interface.patch
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0007-v5.14-futex_waitv.patch
|
0007-v5.14-futex_waitv.patch
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0007-v5.14-winesync.patch
|
0007-v5.14-winesync.patch
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@ -588,6 +589,7 @@ case $_basever in
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|||||||
'fca63d15ca4502aebd73e76d7499b243d2c03db71ff5ab0bf5cf268b2e576320'
|
'fca63d15ca4502aebd73e76d7499b243d2c03db71ff5ab0bf5cf268b2e576320'
|
||||||
'19661ec0d39f9663452b34433214c755179894528bf73a42f6ba52ccf572832a'
|
'19661ec0d39f9663452b34433214c755179894528bf73a42f6ba52ccf572832a'
|
||||||
'aa67e81a27d9062e463594acb91eca6dd13388f23cbe53ca56298f9dba61cc10'
|
'aa67e81a27d9062e463594acb91eca6dd13388f23cbe53ca56298f9dba61cc10'
|
||||||
|
'ee97a751e9b3d2b7ea1707b807ab775cd6f4c392a5efaa475d24d16202518a6a'
|
||||||
'efe5e21706fdf64559ead866c85a5d88c5c3f743d814410df3810ca61cc5b966'
|
'efe5e21706fdf64559ead866c85a5d88c5c3f743d814410df3810ca61cc5b966'
|
||||||
'5742277f41f22bf29fa9742562946b8a01377f8a22adb42ceed3607541c1d5b6'
|
'5742277f41f22bf29fa9742562946b8a01377f8a22adb42ceed3607541c1d5b6'
|
||||||
'034d12a73b507133da2c69a34d61efd2f6b6618549650aa26d748142d22002e1'
|
'034d12a73b507133da2c69a34d61efd2f6b6618549650aa26d748142d22002e1'
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@ -617,7 +619,7 @@ case $_basever in
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0005-glitched-pds.patch
|
0005-glitched-pds.patch
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0006-add-acs-overrides_iommu.patch
|
0006-add-acs-overrides_iommu.patch
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0007-v5.15-fsync.patch
|
0007-v5.15-fsync.patch
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#0007-v5.15-futex2_interface.patch
|
0007-v5.15-fsync-waitvcompat.patch
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0007-v5.15-futex_waitv.patch
|
0007-v5.15-futex_waitv.patch
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0007-v5.15-winesync.patch
|
0007-v5.15-winesync.patch
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#0008-5.14-bcachefs.patch
|
#0008-5.14-bcachefs.patch
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@ -644,7 +646,7 @@ case $_basever in
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'fca63d15ca4502aebd73e76d7499b243d2c03db71ff5ab0bf5cf268b2e576320'
|
'fca63d15ca4502aebd73e76d7499b243d2c03db71ff5ab0bf5cf268b2e576320'
|
||||||
'19661ec0d39f9663452b34433214c755179894528bf73a42f6ba52ccf572832a'
|
'19661ec0d39f9663452b34433214c755179894528bf73a42f6ba52ccf572832a'
|
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'6c4f0099896f69e56ebd8c9eac266ac8ad993acecd50945e0e84ef6f95f9ddca'
|
'6c4f0099896f69e56ebd8c9eac266ac8ad993acecd50945e0e84ef6f95f9ddca'
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#'efe5e21706fdf64559ead866c85a5d88c5c3f743d814410df3810ca61cc5b966'
|
'd6753a5d95a422eeb443edc04dee67512de8408aac1231e8f2e8ff9e000ad48e'
|
||||||
'c8f7c50d9b1418ba22b5ca735c47111a162be416109714d26a674162e5b2cb97'
|
'c8f7c50d9b1418ba22b5ca735c47111a162be416109714d26a674162e5b2cb97'
|
||||||
'034d12a73b507133da2c69a34d61efd2f6b6618549650aa26d748142d22002e1'
|
'034d12a73b507133da2c69a34d61efd2f6b6618549650aa26d748142d22002e1'
|
||||||
'9fad4a40449e09522899955762c8928ae17f4cdaa16e01239fd12592e9d58177'
|
'9fad4a40449e09522899955762c8928ae17f4cdaa16e01239fd12592e9d58177'
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@ -148,6 +148,7 @@ _acs_override=""
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_bcachefs=""
|
_bcachefs=""
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|
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# Set to "true" to enable support for fsync, an experimental replacement for esync found in Valve Proton 4.11+ - https://steamcommunity.com/games/221410/announcements/detail/2957094910196249305
|
# Set to "true" to enable support for fsync, an experimental replacement for esync found in Valve Proton 4.11+ - https://steamcommunity.com/games/221410/announcements/detail/2957094910196249305
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|
# Can be enabled alongside _futex_waitv on 5.14+ to use it as a fallback for older Proton builds
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_fsync="true"
|
_fsync="true"
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|
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# Set to "true" to enable support for futex2, an experimental interface that can be used by proton-tkg and proton 5.13 experimental through Fsync - Can be enabled alongside fsync to use it as a fallback
|
# Set to "true" to enable support for futex2, an experimental interface that can be used by proton-tkg and proton 5.13 experimental through Fsync - Can be enabled alongside fsync to use it as a fallback
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@ -155,7 +156,7 @@ _fsync="true"
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_futex2="true"
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_futex2="true"
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|
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# Set to "true" to enable backported patches to add support for the futex_waitv() syscall, a new interface for fsync. It will appear in mainline at Linux 5.16 release and requires a wine/proton with builtin support for it. It's expected to be available in Valve Proton 6.3 stable soon - https://github.com/ValveSoftware/wine/pull/128
|
# Set to "true" to enable backported patches to add support for the futex_waitv() syscall, a new interface for fsync. It will appear in mainline at Linux 5.16 release and requires a wine/proton with builtin support for it. It's expected to be available in Valve Proton 6.3 stable soon - https://github.com/ValveSoftware/wine/pull/128
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# !! Disables fsync/futex2 interfaces support !!
|
# !! Disables futex2 interfaces support !!
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# https://github.com/andrealmeid/futex_waitv_patches
|
# https://github.com/andrealmeid/futex_waitv_patches
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_futex_waitv="false"
|
_futex_waitv="false"
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|
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@ -1156,7 +1156,7 @@ CONFIG_DEBUG_INFO_BTF_MODULES=y\r
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if [ -z "$_futex_waitv" ]; then
|
if [ -z "$_futex_waitv" ]; then
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plain ""
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plain ""
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plain "Enable support for futex_waitv, backported patches for fsync from 5.16 Kernel"
|
plain "Enable support for futex_waitv, backported patches for fsync from 5.16 Kernel"
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plain "! Will disable fsync/futex2 patchsets !"
|
plain "! Will disable futex2 patchset !"
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plain "https://github.com/andrealmeid/futex_waitv_patches"
|
plain "https://github.com/andrealmeid/futex_waitv_patches"
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plain "https://github.com/ValveSoftware/wine/pull/128"
|
plain "https://github.com/ValveSoftware/wine/pull/128"
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read -rp "`echo $' > N/y : '`" CONDITION9;
|
read -rp "`echo $' > N/y : '`" CONDITION9;
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@ -1164,18 +1164,24 @@ CONFIG_DEBUG_INFO_BTF_MODULES=y\r
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if [[ "$CONDITION9" =~ [yY] ]] || [ "$_futex_waitv" = "true" ]; then
|
if [[ "$CONDITION9" =~ [yY] ]] || [ "$_futex_waitv" = "true" ]; then
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_msg="Patching futex_waitv support"
|
_msg="Patching futex_waitv support"
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_tkg_patcher
|
_tkg_patcher
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_fsync="false"
|
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_futex2="false"
|
_futex2="false"
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fi
|
fi
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fi
|
fi
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|
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# fsync support
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# fsync support
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tkgpatch="$srcdir/0007-v${_basekernel}-fsync.patch"
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if [[ "$CONDITION9" =~ [yY] ]] || [ "$_futex_waitv" = "true" ]; then
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|
tkgpatch="$srcdir/0007-v${_basekernel}-fsync-waitvcompat.patch"
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|
else
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|
tkgpatch="$srcdir/0007-v${_basekernel}-fsync.patch"
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|
fi
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if [ -e "$tkgpatch" ]; then
|
if [ -e "$tkgpatch" ]; then
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if [ -z "$_fsync" ]; then
|
if [ -z "$_fsync" ]; then
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plain ""
|
plain ""
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plain "Enable support for fsync, an experimental replacement for esync in Valve Proton 4.11+"
|
plain "Enable support for fsync, an experimental replacement for esync in Valve Proton 4.11+"
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plain "https://steamcommunity.com/games/221410/announcements/detail/2957094910196249305"
|
plain "https://steamcommunity.com/games/221410/announcements/detail/2957094910196249305"
|
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|
if [[ "$CONDITION9" =~ [yY] ]] || [ "$_futex_waitv" = "true" ]; then
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|
plain "Will be used as a fallback to futex_waitv on older Proton builds if enabled"
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|
fi
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read -rp "`echo $' > N/y : '`" CONDITION10;
|
read -rp "`echo $' > N/y : '`" CONDITION10;
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fi
|
fi
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if [[ "$CONDITION10" =~ [yY] ]] || [ "$_fsync" = "true" ]; then
|
if [[ "$CONDITION10" =~ [yY] ]] || [ "$_fsync" = "true" ]; then
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|
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596
linux-tkg-patches/5.14/0007-v5.14-fsync-waitvcompat.patch
Normal file
596
linux-tkg-patches/5.14/0007-v5.14-fsync-waitvcompat.patch
Normal file
@ -0,0 +1,596 @@
|
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|
From 7ca8de005bdf1940bf0b809fd94f25fb7c7bfa17 Mon Sep 17 00:00:00 2001
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|
From: Gabriel Krisman Bertazi <krisman@collabora.com>
|
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|
Date: Fri, 13 Dec 2019 11:08:02 -0300
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|
Subject: [PATCH] futex: Implement mechanism to wait on any of several futexes
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|
MIME-Version: 1.0
|
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|
Content-Type: text/plain; charset=UTF-8
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|
Content-Transfer-Encoding: 8bit
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|
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|
This is a new futex operation, called FUTEX_WAIT_MULTIPLE, which allows
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|
a thread to wait on several futexes at the same time, and be awoken by
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|
any of them. In a sense, it implements one of the features that was
|
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|
supported by pooling on the old FUTEX_FD interface.
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|
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|
The use case lies in the Wine implementation of the Windows NT interface
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|
WaitMultipleObjects. This Windows API function allows a thread to sleep
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|
waiting on the first of a set of event sources (mutexes, timers, signal,
|
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|
console input, etc) to signal. Considering this is a primitive
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|
synchronization operation for Windows applications, being able to quickly
|
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|
signal events on the producer side, and quickly go to sleep on the
|
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|
consumer side is essential for good performance of those running over Wine.
|
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|
|
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|
Wine developers have an implementation that uses eventfd, but it suffers
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|
from FD exhaustion (there is applications that go to the order of
|
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|
multi-milion FDs), and higher CPU utilization than this new operation.
|
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|
|
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|
The futex list is passed as an array of `struct futex_wait_block`
|
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|
(pointer, value, bitset) to the kernel, which will enqueue all of them
|
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|
and sleep if none was already triggered. It returns a hint of which
|
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|
futex caused the wake up event to userspace, but the hint doesn't
|
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|
guarantee that is the only futex triggered. Before calling the syscall
|
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|
again, userspace should traverse the list, trying to re-acquire any of
|
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|
the other futexes, to prevent an immediate -EWOULDBLOCK return code from
|
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|
the kernel.
|
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|
|
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|
This was tested using three mechanisms:
|
||||||
|
|
||||||
|
1) By reimplementing FUTEX_WAIT in terms of FUTEX_WAIT_MULTIPLE and
|
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|
running the unmodified tools/testing/selftests/futex and a full linux
|
||||||
|
distro on top of this kernel.
|
||||||
|
|
||||||
|
2) By an example code that exercises the FUTEX_WAIT_MULTIPLE path on a
|
||||||
|
multi-threaded, event-handling setup.
|
||||||
|
|
||||||
|
3) By running the Wine fsync implementation and executing multi-threaded
|
||||||
|
applications, in particular modern games, on top of this implementation.
|
||||||
|
|
||||||
|
Changes were tested for the following ABIs: x86_64, i386 and x32.
|
||||||
|
Support for x32 applications is not implemented since it would
|
||||||
|
take a major rework adding a new entry point and splitting the current
|
||||||
|
futex 64 entry point in two and we can't change the current x32 syscall
|
||||||
|
number without breaking user space compatibility.
|
||||||
|
|
||||||
|
CC: Steven Rostedt <rostedt@goodmis.org>
|
||||||
|
Cc: Richard Yao <ryao@gentoo.org>
|
||||||
|
Cc: Thomas Gleixner <tglx@linutronix.de>
|
||||||
|
Cc: Peter Zijlstra <peterz@infradead.org>
|
||||||
|
Co-developed-by: Zebediah Figura <z.figura12@gmail.com>
|
||||||
|
Signed-off-by: Zebediah Figura <z.figura12@gmail.com>
|
||||||
|
Co-developed-by: Steven Noonan <steven@valvesoftware.com>
|
||||||
|
Signed-off-by: Steven Noonan <steven@valvesoftware.com>
|
||||||
|
Co-developed-by: Pierre-Loup A. Griffais <pgriffais@valvesoftware.com>
|
||||||
|
Signed-off-by: Pierre-Loup A. Griffais <pgriffais@valvesoftware.com>
|
||||||
|
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
|
||||||
|
[Added compatibility code]
|
||||||
|
Co-developed-by: André Almeida <andrealmeid@collabora.com>
|
||||||
|
Signed-off-by: André Almeida <andrealmeid@collabora.com>
|
||||||
|
---
|
||||||
|
Changes since v2:
|
||||||
|
- Loop counters are now unsigned
|
||||||
|
- Add ifdef around `in_x32_syscall()`, so this function is only compiled
|
||||||
|
in architectures that declare it
|
||||||
|
|
||||||
|
Changes since RFC:
|
||||||
|
- Limit waitlist to 128 futexes
|
||||||
|
- Simplify wait loop
|
||||||
|
- Document functions
|
||||||
|
- Reduce allocated space
|
||||||
|
- Return hint if a futex was awoken during setup
|
||||||
|
- Check if any futex was awoken prior to sleep
|
||||||
|
- Drop relative timer logic
|
||||||
|
- Add compatibility struct and entry points
|
||||||
|
- Add selftests
|
||||||
|
|
||||||
|
PPA Note: This patch has been modified to build against 5.13
|
||||||
|
---
|
||||||
|
include/uapi/linux/futex.h | 20 +++
|
||||||
|
kernel/futex.c | 351 ++++++++++++++++++++++++++++++++++++-
|
||||||
|
2 files changed, 369 insertions(+), 2 deletions(-)
|
||||||
|
|
||||||
|
diff --git a/include/uapi/linux/futex.h b/include/uapi/linux/futex.h
|
||||||
|
index a89eb0accd5e..580001e89c6c 100644
|
||||||
|
--- a/include/uapi/linux/futex.h
|
||||||
|
+++ b/include/uapi/linux/futex.h
|
||||||
|
@@ -21,6 +21,7 @@
|
||||||
|
#define FUTEX_WAIT_REQUEUE_PI 11
|
||||||
|
#define FUTEX_CMP_REQUEUE_PI 12
|
||||||
|
#define FUTEX_LOCK_PI2 13
|
||||||
|
+#define FUTEX_WAIT_MULTIPLE 14
|
||||||
|
|
||||||
|
#define FUTEX_PRIVATE_FLAG 128
|
||||||
|
#define FUTEX_CLOCK_REALTIME 256
|
||||||
|
@@ -40,6 +41,8 @@
|
||||||
|
FUTEX_PRIVATE_FLAG)
|
||||||
|
#define FUTEX_CMP_REQUEUE_PI_PRIVATE (FUTEX_CMP_REQUEUE_PI | \
|
||||||
|
FUTEX_PRIVATE_FLAG)
|
||||||
|
+#define FUTEX_WAIT_MULTIPLE_PRIVATE (FUTEX_WAIT_MULTIPLE | \
|
||||||
|
+ FUTEX_PRIVATE_FLAG)
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Support for robust futexes: the kernel cleans up held futexes at
|
||||||
|
@@ -150,4 +153,21 @@ struct robust_list_head {
|
||||||
|
(((op & 0xf) << 28) | ((cmp & 0xf) << 24) \
|
||||||
|
| ((oparg & 0xfff) << 12) | (cmparg & 0xfff))
|
||||||
|
|
||||||
|
+/*
|
||||||
|
+ * Maximum number of multiple futexes to wait for
|
||||||
|
+ */
|
||||||
|
+#define FUTEX_MULTIPLE_MAX_COUNT 128
|
||||||
|
+
|
||||||
|
+/**
|
||||||
|
+ * struct futex_wait_block - Block of futexes to be waited for
|
||||||
|
+ * @uaddr: User address of the futex
|
||||||
|
+ * @val: Futex value expected by userspace
|
||||||
|
+ * @bitset: Bitset for the optional bitmasked wakeup
|
||||||
|
+ */
|
||||||
|
+struct futex_wait_block {
|
||||||
|
+ __u32 __user *uaddr;
|
||||||
|
+ __u32 val;
|
||||||
|
+ __u32 bitset;
|
||||||
|
+};
|
||||||
|
+
|
||||||
|
#endif /* _UAPI_LINUX_FUTEX_H */
|
||||||
|
diff --git a/kernel/futex.c b/kernel/futex.c
|
||||||
|
index 45a13eb8894e..b28a6abbdefd 100644
|
||||||
|
--- a/kernel/futex.c
|
||||||
|
+++ b/kernel/futex.c
|
||||||
|
@@ -198,6 +198,8 @@ struct futex_pi_state {
|
||||||
|
* @rt_waiter: rt_waiter storage for use with requeue_pi
|
||||||
|
* @requeue_pi_key: the requeue_pi target futex key
|
||||||
|
* @bitset: bitset for the optional bitmasked wakeup
|
||||||
|
+ * @uaddr: userspace address of futex
|
||||||
|
+ * @uval: expected futex's value
|
||||||
|
*
|
||||||
|
* We use this hashed waitqueue, instead of a normal wait_queue_entry_t, so
|
||||||
|
* we can wake only the relevant ones (hashed queues may be shared).
|
||||||
|
@@ -220,6 +222,8 @@ struct futex_q {
|
||||||
|
struct rt_mutex_waiter *rt_waiter;
|
||||||
|
union futex_key *requeue_pi_key;
|
||||||
|
u32 bitset;
|
||||||
|
+ u32 __user *uaddr;
|
||||||
|
+ u32 uval;
|
||||||
|
} __randomize_layout;
|
||||||
|
|
||||||
|
static const struct futex_q futex_q_init = {
|
||||||
|
@@ -2313,6 +2317,29 @@ static int unqueue_me(struct futex_q *q)
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
+/**
|
||||||
|
+ * unqueue_multiple2() - Remove several futexes from their futex_hash_bucket
|
||||||
|
+ * @q: The list of futexes to unqueue
|
||||||
|
+ * @count: Number of futexes in the list
|
||||||
|
+ *
|
||||||
|
+ * Helper to unqueue a list of futexes. This can't fail.
|
||||||
|
+ *
|
||||||
|
+ * Return:
|
||||||
|
+ * - >=0 - Index of the last futex that was awoken;
|
||||||
|
+ * - -1 - If no futex was awoken
|
||||||
|
+ */
|
||||||
|
+static int unqueue_multiple2(struct futex_q *q, int count)
|
||||||
|
+{
|
||||||
|
+ int ret = -1;
|
||||||
|
+ int i;
|
||||||
|
+
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ if (!unqueue_me(&q[i]))
|
||||||
|
+ ret = i;
|
||||||
|
+ }
|
||||||
|
+ return ret;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
/*
|
||||||
|
* PI futexes can not be requeued and must remove themself from the
|
||||||
|
* hash bucket. The hash bucket lock (i.e. lock_ptr) is held on entry
|
||||||
|
@@ -2680,6 +2707,204 @@ static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags,
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
+/**
|
||||||
|
+ * futex_wait_multiple_setup2() - Prepare to wait and enqueue multiple futexes
|
||||||
|
+ * @qs: The corresponding futex list
|
||||||
|
+ * @count: The size of the lists
|
||||||
|
+ * @flags: Futex flags (FLAGS_SHARED, etc.)
|
||||||
|
+ * @awaken: Index of the last awoken futex
|
||||||
|
+ *
|
||||||
|
+ * Prepare multiple futexes in a single step and enqueue them. This may fail if
|
||||||
|
+ * the futex list is invalid or if any futex was already awoken. On success the
|
||||||
|
+ * task is ready to interruptible sleep.
|
||||||
|
+ *
|
||||||
|
+ * Return:
|
||||||
|
+ * - 1 - One of the futexes was awaken by another thread
|
||||||
|
+ * - 0 - Success
|
||||||
|
+ * - <0 - -EFAULT, -EWOULDBLOCK or -EINVAL
|
||||||
|
+ */
|
||||||
|
+static int futex_wait_multiple_setup2(struct futex_q *qs, int count,
|
||||||
|
+ unsigned int flags, int *awaken)
|
||||||
|
+{
|
||||||
|
+ struct futex_hash_bucket *hb;
|
||||||
|
+ int ret, i;
|
||||||
|
+ u32 uval;
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * Enqueuing multiple futexes is tricky, because we need to
|
||||||
|
+ * enqueue each futex in the list before dealing with the next
|
||||||
|
+ * one to avoid deadlocking on the hash bucket. But, before
|
||||||
|
+ * enqueuing, we need to make sure that current->state is
|
||||||
|
+ * TASK_INTERRUPTIBLE, so we don't absorb any awake events, which
|
||||||
|
+ * cannot be done before the get_futex_key of the next key,
|
||||||
|
+ * because it calls get_user_pages, which can sleep. Thus, we
|
||||||
|
+ * fetch the list of futexes keys in two steps, by first pinning
|
||||||
|
+ * all the memory keys in the futex key, and only then we read
|
||||||
|
+ * each key and queue the corresponding futex.
|
||||||
|
+ */
|
||||||
|
+retry:
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ qs[i].key = FUTEX_KEY_INIT;
|
||||||
|
+ ret = get_futex_key(qs[i].uaddr, flags & FLAGS_SHARED,
|
||||||
|
+ &qs[i].key, FUTEX_READ);
|
||||||
|
+ if (unlikely(ret))
|
||||||
|
+ return ret;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ set_current_state(TASK_INTERRUPTIBLE);
|
||||||
|
+
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ struct futex_q *q = &qs[i];
|
||||||
|
+
|
||||||
|
+ hb = queue_lock(q);
|
||||||
|
+
|
||||||
|
+ ret = get_futex_value_locked(&uval, q->uaddr);
|
||||||
|
+ if (ret) {
|
||||||
|
+ /*
|
||||||
|
+ * We need to try to handle the fault, which
|
||||||
|
+ * cannot be done without sleep, so we need to
|
||||||
|
+ * undo all the work already done, to make sure
|
||||||
|
+ * we don't miss any wake ups. Therefore, clean
|
||||||
|
+ * up, handle the fault and retry from the
|
||||||
|
+ * beginning.
|
||||||
|
+ */
|
||||||
|
+ queue_unlock(hb);
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * Keys 0..(i-1) are implicitly put
|
||||||
|
+ * on unqueue_multiple2.
|
||||||
|
+ */
|
||||||
|
+ *awaken = unqueue_multiple2(qs, i);
|
||||||
|
+
|
||||||
|
+ __set_current_state(TASK_RUNNING);
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * On a real fault, prioritize the error even if
|
||||||
|
+ * some other futex was awoken. Userspace gave
|
||||||
|
+ * us a bad address, -EFAULT them.
|
||||||
|
+ */
|
||||||
|
+ ret = get_user(uval, q->uaddr);
|
||||||
|
+ if (ret)
|
||||||
|
+ return ret;
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * Even if the page fault was handled, If
|
||||||
|
+ * something was already awaken, we can safely
|
||||||
|
+ * give up and succeed to give a hint for userspace to
|
||||||
|
+ * acquire the right futex faster.
|
||||||
|
+ */
|
||||||
|
+ if (*awaken >= 0)
|
||||||
|
+ return 1;
|
||||||
|
+
|
||||||
|
+ goto retry;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (uval != q->uval) {
|
||||||
|
+ queue_unlock(hb);
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * If something was already awaken, we can
|
||||||
|
+ * safely ignore the error and succeed.
|
||||||
|
+ */
|
||||||
|
+ *awaken = unqueue_multiple2(qs, i);
|
||||||
|
+ __set_current_state(TASK_RUNNING);
|
||||||
|
+ if (*awaken >= 0)
|
||||||
|
+ return 1;
|
||||||
|
+
|
||||||
|
+ return -EWOULDBLOCK;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * The bucket lock can't be held while dealing with the
|
||||||
|
+ * next futex. Queue each futex at this moment so hb can
|
||||||
|
+ * be unlocked.
|
||||||
|
+ */
|
||||||
|
+ queue_me(&qs[i], hb);
|
||||||
|
+ }
|
||||||
|
+ return 0;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+/**
|
||||||
|
+ * futex_wait_multiple2() - Prepare to wait on and enqueue several futexes
|
||||||
|
+ * @qs: The list of futexes to wait on
|
||||||
|
+ * @op: Operation code from futex's syscall
|
||||||
|
+ * @count: The number of objects
|
||||||
|
+ * @abs_time: Timeout before giving up and returning to userspace
|
||||||
|
+ *
|
||||||
|
+ * Entry point for the FUTEX_WAIT_MULTIPLE futex operation, this function
|
||||||
|
+ * sleeps on a group of futexes and returns on the first futex that
|
||||||
|
+ * triggered, or after the timeout has elapsed.
|
||||||
|
+ *
|
||||||
|
+ * Return:
|
||||||
|
+ * - >=0 - Hint to the futex that was awoken
|
||||||
|
+ * - <0 - On error
|
||||||
|
+ */
|
||||||
|
+static int futex_wait_multiple2(struct futex_q *qs, int op,
|
||||||
|
+ u32 count, ktime_t *abs_time)
|
||||||
|
+{
|
||||||
|
+ struct hrtimer_sleeper timeout, *to;
|
||||||
|
+ int ret, flags = 0, hint = 0;
|
||||||
|
+ unsigned int i;
|
||||||
|
+
|
||||||
|
+ if (!(op & FUTEX_PRIVATE_FLAG))
|
||||||
|
+ flags |= FLAGS_SHARED;
|
||||||
|
+
|
||||||
|
+ if (op & FUTEX_CLOCK_REALTIME)
|
||||||
|
+ flags |= FLAGS_CLOCKRT;
|
||||||
|
+
|
||||||
|
+ to = futex_setup_timer(abs_time, &timeout, flags, 0);
|
||||||
|
+ while (1) {
|
||||||
|
+ ret = futex_wait_multiple_setup2(qs, count, flags, &hint);
|
||||||
|
+ if (ret) {
|
||||||
|
+ if (ret > 0) {
|
||||||
|
+ /* A futex was awaken during setup */
|
||||||
|
+ ret = hint;
|
||||||
|
+ }
|
||||||
|
+ break;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (to)
|
||||||
|
+ hrtimer_start_expires(&to->timer, HRTIMER_MODE_ABS);
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * Avoid sleeping if another thread already tried to
|
||||||
|
+ * wake us.
|
||||||
|
+ */
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ if (plist_node_empty(&qs[i].list))
|
||||||
|
+ break;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (i == count && (!to || to->task))
|
||||||
|
+ freezable_schedule();
|
||||||
|
+
|
||||||
|
+ ret = unqueue_multiple2(qs, count);
|
||||||
|
+
|
||||||
|
+ __set_current_state(TASK_RUNNING);
|
||||||
|
+
|
||||||
|
+ if (ret >= 0)
|
||||||
|
+ break;
|
||||||
|
+ if (to && !to->task) {
|
||||||
|
+ ret = -ETIMEDOUT;
|
||||||
|
+ break;
|
||||||
|
+ } else if (signal_pending(current)) {
|
||||||
|
+ ret = -ERESTARTSYS;
|
||||||
|
+ break;
|
||||||
|
+ }
|
||||||
|
+ /*
|
||||||
|
+ * The final case is a spurious wakeup, for
|
||||||
|
+ * which just retry.
|
||||||
|
+ */
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (to) {
|
||||||
|
+ hrtimer_cancel(&to->timer);
|
||||||
|
+ destroy_hrtimer_on_stack(&to->timer);
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ return ret;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val,
|
||||||
|
ktime_t *abs_time, u32 bitset)
|
||||||
|
{
|
||||||
|
@@ -3761,6 +3986,43 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
|
||||||
|
return -ENOSYS;
|
||||||
|
}
|
||||||
|
|
||||||
|
+/**
|
||||||
|
+ * futex_read_wait_block - Read an array of futex_wait_block from userspace
|
||||||
|
+ * @uaddr: Userspace address of the block
|
||||||
|
+ * @count: Number of blocks to be read
|
||||||
|
+ *
|
||||||
|
+ * This function creates and allocate an array of futex_q (we zero it to
|
||||||
|
+ * initialize the fields) and then, for each futex_wait_block element from
|
||||||
|
+ * userspace, fill a futex_q element with proper values.
|
||||||
|
+ */
|
||||||
|
+inline struct futex_q *futex_read_wait_block(u32 __user *uaddr, u32 count)
|
||||||
|
+{
|
||||||
|
+ unsigned int i;
|
||||||
|
+ struct futex_q *qs;
|
||||||
|
+ struct futex_wait_block fwb;
|
||||||
|
+ struct futex_wait_block __user *entry =
|
||||||
|
+ (struct futex_wait_block __user *)uaddr;
|
||||||
|
+
|
||||||
|
+ if (!count || count > FUTEX_MULTIPLE_MAX_COUNT)
|
||||||
|
+ return ERR_PTR(-EINVAL);
|
||||||
|
+
|
||||||
|
+ qs = kcalloc(count, sizeof(*qs), GFP_KERNEL);
|
||||||
|
+ if (!qs)
|
||||||
|
+ return ERR_PTR(-ENOMEM);
|
||||||
|
+
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ if (copy_from_user(&fwb, &entry[i], sizeof(fwb))) {
|
||||||
|
+ kfree(qs);
|
||||||
|
+ return ERR_PTR(-EFAULT);
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ qs[i].uaddr = fwb.uaddr;
|
||||||
|
+ qs[i].uval = fwb.val;
|
||||||
|
+ qs[i].bitset = fwb.bitset;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ return qs;
|
||||||
|
+}
|
||||||
|
|
||||||
|
SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
|
||||||
|
struct __kernel_timespec __user *, utime, u32 __user *, uaddr2,
|
||||||
|
@@ -4025,6 +4025,7 @@
|
||||||
|
case FUTEX_LOCK_PI:
|
||||||
|
case FUTEX_WAIT_BITSET:
|
||||||
|
case FUTEX_WAIT_REQUEUE_PI:
|
||||||
|
+ case FUTEX_WAIT_MULTIPLE:
|
||||||
|
return true;
|
||||||
|
}
|
||||||
|
return false;
|
||||||
|
@@ -3796,6 +4059,25 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
|
||||||
|
tp = &t;
|
||||||
|
}
|
||||||
|
|
||||||
|
+ if (cmd == FUTEX_WAIT_MULTIPLE) {
|
||||||
|
+ int ret;
|
||||||
|
+ struct futex_q *qs;
|
||||||
|
+
|
||||||
|
+#ifdef CONFIG_X86_X32
|
||||||
|
+ if (unlikely(in_x32_syscall()))
|
||||||
|
+ return -ENOSYS;
|
||||||
|
+#endif
|
||||||
|
+ qs = futex_read_wait_block(uaddr, val);
|
||||||
|
+
|
||||||
|
+ if (IS_ERR(qs))
|
||||||
|
+ return PTR_ERR(qs);
|
||||||
|
+
|
||||||
|
+ ret = futex_wait_multiple2(qs, op, val, tp);
|
||||||
|
+ kfree(qs);
|
||||||
|
+
|
||||||
|
+ return ret;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
return do_futex(uaddr, op, val, tp, uaddr2, (unsigned long)utime, val3);
|
||||||
|
}
|
||||||
|
|
||||||
|
@@ -3958,6 +4240,57 @@ COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid,
|
||||||
|
#endif /* CONFIG_COMPAT */
|
||||||
|
|
||||||
|
#ifdef CONFIG_COMPAT_32BIT_TIME
|
||||||
|
+/**
|
||||||
|
+ * struct compat_futex_wait_block - Block of futexes to be waited for
|
||||||
|
+ * @uaddr: User address of the futex (compatible pointer)
|
||||||
|
+ * @val: Futex value expected by userspace
|
||||||
|
+ * @bitset: Bitset for the optional bitmasked wakeup
|
||||||
|
+ */
|
||||||
|
+struct compat_futex_wait_block {
|
||||||
|
+ compat_uptr_t uaddr;
|
||||||
|
+ __u32 val;
|
||||||
|
+ __u32 bitset;
|
||||||
|
+};
|
||||||
|
+
|
||||||
|
+/**
|
||||||
|
+ * compat_futex_read_wait_block - Read an array of futex_wait_block from
|
||||||
|
+ * userspace
|
||||||
|
+ * @uaddr: Userspace address of the block
|
||||||
|
+ * @count: Number of blocks to be read
|
||||||
|
+ *
|
||||||
|
+ * This function does the same as futex_read_wait_block(), except that it
|
||||||
|
+ * converts the pointer to the futex from the compat version to the regular one.
|
||||||
|
+ */
|
||||||
|
+inline struct futex_q *compat_futex_read_wait_block(u32 __user *uaddr,
|
||||||
|
+ u32 count)
|
||||||
|
+{
|
||||||
|
+ unsigned int i;
|
||||||
|
+ struct futex_q *qs;
|
||||||
|
+ struct compat_futex_wait_block fwb;
|
||||||
|
+ struct compat_futex_wait_block __user *entry =
|
||||||
|
+ (struct compat_futex_wait_block __user *)uaddr;
|
||||||
|
+
|
||||||
|
+ if (!count || count > FUTEX_MULTIPLE_MAX_COUNT)
|
||||||
|
+ return ERR_PTR(-EINVAL);
|
||||||
|
+
|
||||||
|
+ qs = kcalloc(count, sizeof(*qs), GFP_KERNEL);
|
||||||
|
+ if (!qs)
|
||||||
|
+ return ERR_PTR(-ENOMEM);
|
||||||
|
+
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ if (copy_from_user(&fwb, &entry[i], sizeof(fwb))) {
|
||||||
|
+ kfree(qs);
|
||||||
|
+ return ERR_PTR(-EFAULT);
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ qs[i].uaddr = compat_ptr(fwb.uaddr);
|
||||||
|
+ qs[i].uval = fwb.val;
|
||||||
|
+ qs[i].bitset = fwb.bitset;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ return qs;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val,
|
||||||
|
struct old_timespec32 __user *, utime, u32 __user *, uaddr2,
|
||||||
|
u32, val3)
|
||||||
|
@@ -3986,6 +4320,19 @@ SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val,
|
||||||
|
tp = &t;
|
||||||
|
}
|
||||||
|
|
||||||
|
+ if (cmd == FUTEX_WAIT_MULTIPLE) {
|
||||||
|
+ int ret;
|
||||||
|
+ struct futex_q *qs = compat_futex_read_wait_block(uaddr, val);
|
||||||
|
+
|
||||||
|
+ if (IS_ERR(qs))
|
||||||
|
+ return PTR_ERR(qs);
|
||||||
|
+
|
||||||
|
+ ret = futex_wait_multiple2(qs, op, val, tp);
|
||||||
|
+ kfree(qs);
|
||||||
|
+
|
||||||
|
+ return ret;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
return do_futex(uaddr, op, val, tp, uaddr2, (unsigned long)utime, val3);
|
||||||
|
}
|
||||||
|
#endif /* CONFIG_COMPAT_32BIT_TIME */
|
||||||
|
--
|
||||||
|
GitLab
|
||||||
|
|
||||||
|
From cdaa060153c4adf0a64d7bbf7e3ebba727c7e335 Mon Sep 17 00:00:00 2001
|
||||||
|
From: =?UTF-8?q?Andr=C3=A9=20Almeida?= <andrealmeid@collabora.com>
|
||||||
|
Date: Fri, 7 Feb 2020 23:28:02 -0300
|
||||||
|
Subject: [PATCH] futex: Add Proton compatibility code
|
||||||
|
|
||||||
|
PPA Note: This patch has been modified to build against 5.13
|
||||||
|
---
|
||||||
|
include/uapi/linux/futex.h | 2 +-
|
||||||
|
kernel/futex.c | 5 +++--
|
||||||
|
2 files changed, 4 insertions(+), 3 deletions(-)
|
||||||
|
|
||||||
|
diff --git a/include/uapi/linux/futex.h b/include/uapi/linux/futex.h
|
||||||
|
index 580001e89c6c..a3e760886b8e 100644
|
||||||
|
--- a/include/uapi/linux/futex.h
|
||||||
|
+++ b/include/uapi/linux/futex.h
|
||||||
|
@@ -21,7 +21,7 @@
|
||||||
|
#define FUTEX_WAIT_REQUEUE_PI 11
|
||||||
|
#define FUTEX_CMP_REQUEUE_PI 12
|
||||||
|
#define FUTEX_LOCK_PI2 13
|
||||||
|
-#define FUTEX_WAIT_MULTIPLE 14
|
||||||
|
+#define FUTEX_WAIT_MULTIPLE 31
|
||||||
|
|
||||||
|
#define FUTEX_PRIVATE_FLAG 128
|
||||||
|
#define FUTEX_CLOCK_REALTIME 256
|
||||||
|
diff --git a/kernel/futex.c b/kernel/futex.c
|
||||||
|
index b28a6abbdefd..5b547c911b92 100644
|
||||||
|
--- a/kernel/futex.c
|
||||||
|
+++ b/kernel/futex.c
|
||||||
|
@@ -4038,7 +4038,7 @@
|
||||||
|
return -EINVAL;
|
||||||
|
|
||||||
|
*t = timespec64_to_ktime(*ts);
|
||||||
|
- if (cmd == FUTEX_WAIT)
|
||||||
|
+ if (cmd == FUTEX_WAIT || cmd == FUTEX_WAIT_MULTIPLE)
|
||||||
|
*t = ktime_add_safe(ktime_get(), *t);
|
||||||
|
else if (cmd != FUTEX_LOCK_PI && !(op & FUTEX_CLOCK_REALTIME))
|
||||||
|
*t = timens_ktime_to_host(CLOCK_MONOTONIC, *t);
|
||||||
|
@@ -4248,6 +4248,7 @@ COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid,
|
||||||
|
*/
|
||||||
|
struct compat_futex_wait_block {
|
||||||
|
compat_uptr_t uaddr;
|
||||||
|
+ __u32 pad;
|
||||||
|
__u32 val;
|
||||||
|
__u32 bitset;
|
||||||
|
};
|
||||||
|
--
|
||||||
|
GitLab
|
||||||
|
|
||||||
596
linux-tkg-patches/5.15/0007-v5.15-fsync-waitvcompat.patch
Normal file
596
linux-tkg-patches/5.15/0007-v5.15-fsync-waitvcompat.patch
Normal file
@ -0,0 +1,596 @@
|
|||||||
|
From 7ca8de005bdf1940bf0b809fd94f25fb7c7bfa17 Mon Sep 17 00:00:00 2001
|
||||||
|
From: Gabriel Krisman Bertazi <krisman@collabora.com>
|
||||||
|
Date: Fri, 13 Dec 2019 11:08:02 -0300
|
||||||
|
Subject: [PATCH] futex: Implement mechanism to wait on any of several futexes
|
||||||
|
MIME-Version: 1.0
|
||||||
|
Content-Type: text/plain; charset=UTF-8
|
||||||
|
Content-Transfer-Encoding: 8bit
|
||||||
|
|
||||||
|
This is a new futex operation, called FUTEX_WAIT_MULTIPLE, which allows
|
||||||
|
a thread to wait on several futexes at the same time, and be awoken by
|
||||||
|
any of them. In a sense, it implements one of the features that was
|
||||||
|
supported by pooling on the old FUTEX_FD interface.
|
||||||
|
|
||||||
|
The use case lies in the Wine implementation of the Windows NT interface
|
||||||
|
WaitMultipleObjects. This Windows API function allows a thread to sleep
|
||||||
|
waiting on the first of a set of event sources (mutexes, timers, signal,
|
||||||
|
console input, etc) to signal. Considering this is a primitive
|
||||||
|
synchronization operation for Windows applications, being able to quickly
|
||||||
|
signal events on the producer side, and quickly go to sleep on the
|
||||||
|
consumer side is essential for good performance of those running over Wine.
|
||||||
|
|
||||||
|
Wine developers have an implementation that uses eventfd, but it suffers
|
||||||
|
from FD exhaustion (there is applications that go to the order of
|
||||||
|
multi-milion FDs), and higher CPU utilization than this new operation.
|
||||||
|
|
||||||
|
The futex list is passed as an array of `struct futex_wait_block`
|
||||||
|
(pointer, value, bitset) to the kernel, which will enqueue all of them
|
||||||
|
and sleep if none was already triggered. It returns a hint of which
|
||||||
|
futex caused the wake up event to userspace, but the hint doesn't
|
||||||
|
guarantee that is the only futex triggered. Before calling the syscall
|
||||||
|
again, userspace should traverse the list, trying to re-acquire any of
|
||||||
|
the other futexes, to prevent an immediate -EWOULDBLOCK return code from
|
||||||
|
the kernel.
|
||||||
|
|
||||||
|
This was tested using three mechanisms:
|
||||||
|
|
||||||
|
1) By reimplementing FUTEX_WAIT in terms of FUTEX_WAIT_MULTIPLE and
|
||||||
|
running the unmodified tools/testing/selftests/futex and a full linux
|
||||||
|
distro on top of this kernel.
|
||||||
|
|
||||||
|
2) By an example code that exercises the FUTEX_WAIT_MULTIPLE path on a
|
||||||
|
multi-threaded, event-handling setup.
|
||||||
|
|
||||||
|
3) By running the Wine fsync implementation and executing multi-threaded
|
||||||
|
applications, in particular modern games, on top of this implementation.
|
||||||
|
|
||||||
|
Changes were tested for the following ABIs: x86_64, i386 and x32.
|
||||||
|
Support for x32 applications is not implemented since it would
|
||||||
|
take a major rework adding a new entry point and splitting the current
|
||||||
|
futex 64 entry point in two and we can't change the current x32 syscall
|
||||||
|
number without breaking user space compatibility.
|
||||||
|
|
||||||
|
CC: Steven Rostedt <rostedt@goodmis.org>
|
||||||
|
Cc: Richard Yao <ryao@gentoo.org>
|
||||||
|
Cc: Thomas Gleixner <tglx@linutronix.de>
|
||||||
|
Cc: Peter Zijlstra <peterz@infradead.org>
|
||||||
|
Co-developed-by: Zebediah Figura <z.figura12@gmail.com>
|
||||||
|
Signed-off-by: Zebediah Figura <z.figura12@gmail.com>
|
||||||
|
Co-developed-by: Steven Noonan <steven@valvesoftware.com>
|
||||||
|
Signed-off-by: Steven Noonan <steven@valvesoftware.com>
|
||||||
|
Co-developed-by: Pierre-Loup A. Griffais <pgriffais@valvesoftware.com>
|
||||||
|
Signed-off-by: Pierre-Loup A. Griffais <pgriffais@valvesoftware.com>
|
||||||
|
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
|
||||||
|
[Added compatibility code]
|
||||||
|
Co-developed-by: André Almeida <andrealmeid@collabora.com>
|
||||||
|
Signed-off-by: André Almeida <andrealmeid@collabora.com>
|
||||||
|
---
|
||||||
|
Changes since v2:
|
||||||
|
- Loop counters are now unsigned
|
||||||
|
- Add ifdef around `in_x32_syscall()`, so this function is only compiled
|
||||||
|
in architectures that declare it
|
||||||
|
|
||||||
|
Changes since RFC:
|
||||||
|
- Limit waitlist to 128 futexes
|
||||||
|
- Simplify wait loop
|
||||||
|
- Document functions
|
||||||
|
- Reduce allocated space
|
||||||
|
- Return hint if a futex was awoken during setup
|
||||||
|
- Check if any futex was awoken prior to sleep
|
||||||
|
- Drop relative timer logic
|
||||||
|
- Add compatibility struct and entry points
|
||||||
|
- Add selftests
|
||||||
|
|
||||||
|
PPA Note: This patch has been modified to build against 5.13
|
||||||
|
---
|
||||||
|
include/uapi/linux/futex.h | 20 +++
|
||||||
|
kernel/futex.c | 351 ++++++++++++++++++++++++++++++++++++-
|
||||||
|
2 files changed, 369 insertions(+), 2 deletions(-)
|
||||||
|
|
||||||
|
diff --git a/include/uapi/linux/futex.h b/include/uapi/linux/futex.h
|
||||||
|
index a89eb0accd5e..580001e89c6c 100644
|
||||||
|
--- a/include/uapi/linux/futex.h
|
||||||
|
+++ b/include/uapi/linux/futex.h
|
||||||
|
@@ -21,6 +21,7 @@
|
||||||
|
#define FUTEX_WAIT_REQUEUE_PI 11
|
||||||
|
#define FUTEX_CMP_REQUEUE_PI 12
|
||||||
|
#define FUTEX_LOCK_PI2 13
|
||||||
|
+#define FUTEX_WAIT_MULTIPLE 14
|
||||||
|
|
||||||
|
#define FUTEX_PRIVATE_FLAG 128
|
||||||
|
#define FUTEX_CLOCK_REALTIME 256
|
||||||
|
@@ -40,6 +41,8 @@
|
||||||
|
FUTEX_PRIVATE_FLAG)
|
||||||
|
#define FUTEX_CMP_REQUEUE_PI_PRIVATE (FUTEX_CMP_REQUEUE_PI | \
|
||||||
|
FUTEX_PRIVATE_FLAG)
|
||||||
|
+#define FUTEX_WAIT_MULTIPLE_PRIVATE (FUTEX_WAIT_MULTIPLE | \
|
||||||
|
+ FUTEX_PRIVATE_FLAG)
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Support for robust futexes: the kernel cleans up held futexes at
|
||||||
|
@@ -150,4 +153,21 @@ struct robust_list_head {
|
||||||
|
(((op & 0xf) << 28) | ((cmp & 0xf) << 24) \
|
||||||
|
| ((oparg & 0xfff) << 12) | (cmparg & 0xfff))
|
||||||
|
|
||||||
|
+/*
|
||||||
|
+ * Maximum number of multiple futexes to wait for
|
||||||
|
+ */
|
||||||
|
+#define FUTEX_MULTIPLE_MAX_COUNT 128
|
||||||
|
+
|
||||||
|
+/**
|
||||||
|
+ * struct futex_wait_block - Block of futexes to be waited for
|
||||||
|
+ * @uaddr: User address of the futex
|
||||||
|
+ * @val: Futex value expected by userspace
|
||||||
|
+ * @bitset: Bitset for the optional bitmasked wakeup
|
||||||
|
+ */
|
||||||
|
+struct futex_wait_block {
|
||||||
|
+ __u32 __user *uaddr;
|
||||||
|
+ __u32 val;
|
||||||
|
+ __u32 bitset;
|
||||||
|
+};
|
||||||
|
+
|
||||||
|
#endif /* _UAPI_LINUX_FUTEX_H */
|
||||||
|
diff --git a/kernel/futex.c b/kernel/futex.c
|
||||||
|
index 45a13eb8894e..b28a6abbdefd 100644
|
||||||
|
--- a/kernel/futex.c
|
||||||
|
+++ b/kernel/futex.c
|
||||||
|
@@ -198,6 +198,8 @@ struct futex_pi_state {
|
||||||
|
* @bitset: bitset for the optional bitmasked wakeup
|
||||||
|
* @requeue_state: State field for futex_requeue_pi()
|
||||||
|
* @requeue_wait: RCU wait for futex_requeue_pi() (RT only)
|
||||||
|
+ * @uaddr: userspace address of futex
|
||||||
|
+ * @uval: expected futex's value
|
||||||
|
*
|
||||||
|
* We use this hashed waitqueue, instead of a normal wait_queue_entry_t, so
|
||||||
|
* we can wake only the relevant ones (hashed queues may be shared).
|
||||||
|
@@ -220,6 +222,8 @@ struct futex_q {
|
||||||
|
union futex_key *requeue_pi_key;
|
||||||
|
u32 bitset;
|
||||||
|
atomic_t requeue_state;
|
||||||
|
+ u32 __user *uaddr;
|
||||||
|
+ u32 uval;
|
||||||
|
#ifdef CONFIG_PREEMPT_RT
|
||||||
|
struct rcuwait requeue_wait;
|
||||||
|
#endif
|
||||||
|
@@ -2313,6 +2317,29 @@ static int unqueue_me(struct futex_q *q)
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
+/**
|
||||||
|
+ * unqueue_multiple2() - Remove several futexes from their futex_hash_bucket
|
||||||
|
+ * @q: The list of futexes to unqueue
|
||||||
|
+ * @count: Number of futexes in the list
|
||||||
|
+ *
|
||||||
|
+ * Helper to unqueue a list of futexes. This can't fail.
|
||||||
|
+ *
|
||||||
|
+ * Return:
|
||||||
|
+ * - >=0 - Index of the last futex that was awoken;
|
||||||
|
+ * - -1 - If no futex was awoken
|
||||||
|
+ */
|
||||||
|
+static int unqueue_multiple2(struct futex_q *q, int count)
|
||||||
|
+{
|
||||||
|
+ int ret = -1;
|
||||||
|
+ int i;
|
||||||
|
+
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ if (!unqueue_me(&q[i]))
|
||||||
|
+ ret = i;
|
||||||
|
+ }
|
||||||
|
+ return ret;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
/*
|
||||||
|
* PI futexes can not be requeued and must remove themself from the
|
||||||
|
* hash bucket. The hash bucket lock (i.e. lock_ptr) is held on entry
|
||||||
|
@@ -2680,6 +2707,204 @@ static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags,
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
+/**
|
||||||
|
+ * futex_wait_multiple_setup2() - Prepare to wait and enqueue multiple futexes
|
||||||
|
+ * @qs: The corresponding futex list
|
||||||
|
+ * @count: The size of the lists
|
||||||
|
+ * @flags: Futex flags (FLAGS_SHARED, etc.)
|
||||||
|
+ * @awaken: Index of the last awoken futex
|
||||||
|
+ *
|
||||||
|
+ * Prepare multiple futexes in a single step and enqueue them. This may fail if
|
||||||
|
+ * the futex list is invalid or if any futex was already awoken. On success the
|
||||||
|
+ * task is ready to interruptible sleep.
|
||||||
|
+ *
|
||||||
|
+ * Return:
|
||||||
|
+ * - 1 - One of the futexes was awaken by another thread
|
||||||
|
+ * - 0 - Success
|
||||||
|
+ * - <0 - -EFAULT, -EWOULDBLOCK or -EINVAL
|
||||||
|
+ */
|
||||||
|
+static int futex_wait_multiple_setup2(struct futex_q *qs, int count,
|
||||||
|
+ unsigned int flags, int *awaken)
|
||||||
|
+{
|
||||||
|
+ struct futex_hash_bucket *hb;
|
||||||
|
+ int ret, i;
|
||||||
|
+ u32 uval;
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * Enqueuing multiple futexes is tricky, because we need to
|
||||||
|
+ * enqueue each futex in the list before dealing with the next
|
||||||
|
+ * one to avoid deadlocking on the hash bucket. But, before
|
||||||
|
+ * enqueuing, we need to make sure that current->state is
|
||||||
|
+ * TASK_INTERRUPTIBLE, so we don't absorb any awake events, which
|
||||||
|
+ * cannot be done before the get_futex_key of the next key,
|
||||||
|
+ * because it calls get_user_pages, which can sleep. Thus, we
|
||||||
|
+ * fetch the list of futexes keys in two steps, by first pinning
|
||||||
|
+ * all the memory keys in the futex key, and only then we read
|
||||||
|
+ * each key and queue the corresponding futex.
|
||||||
|
+ */
|
||||||
|
+retry:
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ qs[i].key = FUTEX_KEY_INIT;
|
||||||
|
+ ret = get_futex_key(qs[i].uaddr, flags & FLAGS_SHARED,
|
||||||
|
+ &qs[i].key, FUTEX_READ);
|
||||||
|
+ if (unlikely(ret))
|
||||||
|
+ return ret;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ set_current_state(TASK_INTERRUPTIBLE);
|
||||||
|
+
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ struct futex_q *q = &qs[i];
|
||||||
|
+
|
||||||
|
+ hb = queue_lock(q);
|
||||||
|
+
|
||||||
|
+ ret = get_futex_value_locked(&uval, q->uaddr);
|
||||||
|
+ if (ret) {
|
||||||
|
+ /*
|
||||||
|
+ * We need to try to handle the fault, which
|
||||||
|
+ * cannot be done without sleep, so we need to
|
||||||
|
+ * undo all the work already done, to make sure
|
||||||
|
+ * we don't miss any wake ups. Therefore, clean
|
||||||
|
+ * up, handle the fault and retry from the
|
||||||
|
+ * beginning.
|
||||||
|
+ */
|
||||||
|
+ queue_unlock(hb);
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * Keys 0..(i-1) are implicitly put
|
||||||
|
+ * on unqueue_multiple2.
|
||||||
|
+ */
|
||||||
|
+ *awaken = unqueue_multiple2(qs, i);
|
||||||
|
+
|
||||||
|
+ __set_current_state(TASK_RUNNING);
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * On a real fault, prioritize the error even if
|
||||||
|
+ * some other futex was awoken. Userspace gave
|
||||||
|
+ * us a bad address, -EFAULT them.
|
||||||
|
+ */
|
||||||
|
+ ret = get_user(uval, q->uaddr);
|
||||||
|
+ if (ret)
|
||||||
|
+ return ret;
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * Even if the page fault was handled, If
|
||||||
|
+ * something was already awaken, we can safely
|
||||||
|
+ * give up and succeed to give a hint for userspace to
|
||||||
|
+ * acquire the right futex faster.
|
||||||
|
+ */
|
||||||
|
+ if (*awaken >= 0)
|
||||||
|
+ return 1;
|
||||||
|
+
|
||||||
|
+ goto retry;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (uval != q->uval) {
|
||||||
|
+ queue_unlock(hb);
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * If something was already awaken, we can
|
||||||
|
+ * safely ignore the error and succeed.
|
||||||
|
+ */
|
||||||
|
+ *awaken = unqueue_multiple2(qs, i);
|
||||||
|
+ __set_current_state(TASK_RUNNING);
|
||||||
|
+ if (*awaken >= 0)
|
||||||
|
+ return 1;
|
||||||
|
+
|
||||||
|
+ return -EWOULDBLOCK;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * The bucket lock can't be held while dealing with the
|
||||||
|
+ * next futex. Queue each futex at this moment so hb can
|
||||||
|
+ * be unlocked.
|
||||||
|
+ */
|
||||||
|
+ queue_me(&qs[i], hb);
|
||||||
|
+ }
|
||||||
|
+ return 0;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
+/**
|
||||||
|
+ * futex_wait_multiple2() - Prepare to wait on and enqueue several futexes
|
||||||
|
+ * @qs: The list of futexes to wait on
|
||||||
|
+ * @op: Operation code from futex's syscall
|
||||||
|
+ * @count: The number of objects
|
||||||
|
+ * @abs_time: Timeout before giving up and returning to userspace
|
||||||
|
+ *
|
||||||
|
+ * Entry point for the FUTEX_WAIT_MULTIPLE futex operation, this function
|
||||||
|
+ * sleeps on a group of futexes and returns on the first futex that
|
||||||
|
+ * triggered, or after the timeout has elapsed.
|
||||||
|
+ *
|
||||||
|
+ * Return:
|
||||||
|
+ * - >=0 - Hint to the futex that was awoken
|
||||||
|
+ * - <0 - On error
|
||||||
|
+ */
|
||||||
|
+static int futex_wait_multiple2(struct futex_q *qs, int op,
|
||||||
|
+ u32 count, ktime_t *abs_time)
|
||||||
|
+{
|
||||||
|
+ struct hrtimer_sleeper timeout, *to;
|
||||||
|
+ int ret, flags = 0, hint = 0;
|
||||||
|
+ unsigned int i;
|
||||||
|
+
|
||||||
|
+ if (!(op & FUTEX_PRIVATE_FLAG))
|
||||||
|
+ flags |= FLAGS_SHARED;
|
||||||
|
+
|
||||||
|
+ if (op & FUTEX_CLOCK_REALTIME)
|
||||||
|
+ flags |= FLAGS_CLOCKRT;
|
||||||
|
+
|
||||||
|
+ to = futex_setup_timer(abs_time, &timeout, flags, 0);
|
||||||
|
+ while (1) {
|
||||||
|
+ ret = futex_wait_multiple_setup2(qs, count, flags, &hint);
|
||||||
|
+ if (ret) {
|
||||||
|
+ if (ret > 0) {
|
||||||
|
+ /* A futex was awaken during setup */
|
||||||
|
+ ret = hint;
|
||||||
|
+ }
|
||||||
|
+ break;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (to)
|
||||||
|
+ hrtimer_start_expires(&to->timer, HRTIMER_MODE_ABS);
|
||||||
|
+
|
||||||
|
+ /*
|
||||||
|
+ * Avoid sleeping if another thread already tried to
|
||||||
|
+ * wake us.
|
||||||
|
+ */
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ if (plist_node_empty(&qs[i].list))
|
||||||
|
+ break;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (i == count && (!to || to->task))
|
||||||
|
+ freezable_schedule();
|
||||||
|
+
|
||||||
|
+ ret = unqueue_multiple2(qs, count);
|
||||||
|
+
|
||||||
|
+ __set_current_state(TASK_RUNNING);
|
||||||
|
+
|
||||||
|
+ if (ret >= 0)
|
||||||
|
+ break;
|
||||||
|
+ if (to && !to->task) {
|
||||||
|
+ ret = -ETIMEDOUT;
|
||||||
|
+ break;
|
||||||
|
+ } else if (signal_pending(current)) {
|
||||||
|
+ ret = -ERESTARTSYS;
|
||||||
|
+ break;
|
||||||
|
+ }
|
||||||
|
+ /*
|
||||||
|
+ * The final case is a spurious wakeup, for
|
||||||
|
+ * which just retry.
|
||||||
|
+ */
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (to) {
|
||||||
|
+ hrtimer_cancel(&to->timer);
|
||||||
|
+ destroy_hrtimer_on_stack(&to->timer);
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ return ret;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val,
|
||||||
|
ktime_t *abs_time, u32 bitset)
|
||||||
|
{
|
||||||
|
@@ -3761,6 +3986,43 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
|
||||||
|
return -ENOSYS;
|
||||||
|
}
|
||||||
|
|
||||||
|
+/**
|
||||||
|
+ * futex_read_wait_block - Read an array of futex_wait_block from userspace
|
||||||
|
+ * @uaddr: Userspace address of the block
|
||||||
|
+ * @count: Number of blocks to be read
|
||||||
|
+ *
|
||||||
|
+ * This function creates and allocate an array of futex_q (we zero it to
|
||||||
|
+ * initialize the fields) and then, for each futex_wait_block element from
|
||||||
|
+ * userspace, fill a futex_q element with proper values.
|
||||||
|
+ */
|
||||||
|
+inline struct futex_q *futex_read_wait_block(u32 __user *uaddr, u32 count)
|
||||||
|
+{
|
||||||
|
+ unsigned int i;
|
||||||
|
+ struct futex_q *qs;
|
||||||
|
+ struct futex_wait_block fwb;
|
||||||
|
+ struct futex_wait_block __user *entry =
|
||||||
|
+ (struct futex_wait_block __user *)uaddr;
|
||||||
|
+
|
||||||
|
+ if (!count || count > FUTEX_MULTIPLE_MAX_COUNT)
|
||||||
|
+ return ERR_PTR(-EINVAL);
|
||||||
|
+
|
||||||
|
+ qs = kcalloc(count, sizeof(*qs), GFP_KERNEL);
|
||||||
|
+ if (!qs)
|
||||||
|
+ return ERR_PTR(-ENOMEM);
|
||||||
|
+
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ if (copy_from_user(&fwb, &entry[i], sizeof(fwb))) {
|
||||||
|
+ kfree(qs);
|
||||||
|
+ return ERR_PTR(-EFAULT);
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ qs[i].uaddr = fwb.uaddr;
|
||||||
|
+ qs[i].uval = fwb.val;
|
||||||
|
+ qs[i].bitset = fwb.bitset;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ return qs;
|
||||||
|
+}
|
||||||
|
|
||||||
|
SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
|
||||||
|
struct __kernel_timespec __user *, utime, u32 __user *, uaddr2,
|
||||||
|
@@ -4025,6 +4025,7 @@
|
||||||
|
case FUTEX_LOCK_PI:
|
||||||
|
case FUTEX_WAIT_BITSET:
|
||||||
|
case FUTEX_WAIT_REQUEUE_PI:
|
||||||
|
+ case FUTEX_WAIT_MULTIPLE:
|
||||||
|
return true;
|
||||||
|
}
|
||||||
|
return false;
|
||||||
|
@@ -3796,6 +4059,25 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
|
||||||
|
tp = &t;
|
||||||
|
}
|
||||||
|
|
||||||
|
+ if (cmd == FUTEX_WAIT_MULTIPLE) {
|
||||||
|
+ int ret;
|
||||||
|
+ struct futex_q *qs;
|
||||||
|
+
|
||||||
|
+#ifdef CONFIG_X86_X32
|
||||||
|
+ if (unlikely(in_x32_syscall()))
|
||||||
|
+ return -ENOSYS;
|
||||||
|
+#endif
|
||||||
|
+ qs = futex_read_wait_block(uaddr, val);
|
||||||
|
+
|
||||||
|
+ if (IS_ERR(qs))
|
||||||
|
+ return PTR_ERR(qs);
|
||||||
|
+
|
||||||
|
+ ret = futex_wait_multiple2(qs, op, val, tp);
|
||||||
|
+ kfree(qs);
|
||||||
|
+
|
||||||
|
+ return ret;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
return do_futex(uaddr, op, val, tp, uaddr2, (unsigned long)utime, val3);
|
||||||
|
}
|
||||||
|
|
||||||
|
@@ -3958,6 +4240,57 @@ COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid,
|
||||||
|
#endif /* CONFIG_COMPAT */
|
||||||
|
|
||||||
|
#ifdef CONFIG_COMPAT_32BIT_TIME
|
||||||
|
+/**
|
||||||
|
+ * struct compat_futex_wait_block - Block of futexes to be waited for
|
||||||
|
+ * @uaddr: User address of the futex (compatible pointer)
|
||||||
|
+ * @val: Futex value expected by userspace
|
||||||
|
+ * @bitset: Bitset for the optional bitmasked wakeup
|
||||||
|
+ */
|
||||||
|
+struct compat_futex_wait_block {
|
||||||
|
+ compat_uptr_t uaddr;
|
||||||
|
+ __u32 val;
|
||||||
|
+ __u32 bitset;
|
||||||
|
+};
|
||||||
|
+
|
||||||
|
+/**
|
||||||
|
+ * compat_futex_read_wait_block - Read an array of futex_wait_block from
|
||||||
|
+ * userspace
|
||||||
|
+ * @uaddr: Userspace address of the block
|
||||||
|
+ * @count: Number of blocks to be read
|
||||||
|
+ *
|
||||||
|
+ * This function does the same as futex_read_wait_block(), except that it
|
||||||
|
+ * converts the pointer to the futex from the compat version to the regular one.
|
||||||
|
+ */
|
||||||
|
+inline struct futex_q *compat_futex_read_wait_block(u32 __user *uaddr,
|
||||||
|
+ u32 count)
|
||||||
|
+{
|
||||||
|
+ unsigned int i;
|
||||||
|
+ struct futex_q *qs;
|
||||||
|
+ struct compat_futex_wait_block fwb;
|
||||||
|
+ struct compat_futex_wait_block __user *entry =
|
||||||
|
+ (struct compat_futex_wait_block __user *)uaddr;
|
||||||
|
+
|
||||||
|
+ if (!count || count > FUTEX_MULTIPLE_MAX_COUNT)
|
||||||
|
+ return ERR_PTR(-EINVAL);
|
||||||
|
+
|
||||||
|
+ qs = kcalloc(count, sizeof(*qs), GFP_KERNEL);
|
||||||
|
+ if (!qs)
|
||||||
|
+ return ERR_PTR(-ENOMEM);
|
||||||
|
+
|
||||||
|
+ for (i = 0; i < count; i++) {
|
||||||
|
+ if (copy_from_user(&fwb, &entry[i], sizeof(fwb))) {
|
||||||
|
+ kfree(qs);
|
||||||
|
+ return ERR_PTR(-EFAULT);
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ qs[i].uaddr = compat_ptr(fwb.uaddr);
|
||||||
|
+ qs[i].uval = fwb.val;
|
||||||
|
+ qs[i].bitset = fwb.bitset;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ return qs;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val,
|
||||||
|
struct old_timespec32 __user *, utime, u32 __user *, uaddr2,
|
||||||
|
u32, val3)
|
||||||
|
@@ -3986,6 +4320,19 @@ SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val,
|
||||||
|
tp = &t;
|
||||||
|
}
|
||||||
|
|
||||||
|
+ if (cmd == FUTEX_WAIT_MULTIPLE) {
|
||||||
|
+ int ret;
|
||||||
|
+ struct futex_q *qs = compat_futex_read_wait_block(uaddr, val);
|
||||||
|
+
|
||||||
|
+ if (IS_ERR(qs))
|
||||||
|
+ return PTR_ERR(qs);
|
||||||
|
+
|
||||||
|
+ ret = futex_wait_multiple2(qs, op, val, tp);
|
||||||
|
+ kfree(qs);
|
||||||
|
+
|
||||||
|
+ return ret;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
return do_futex(uaddr, op, val, tp, uaddr2, (unsigned long)utime, val3);
|
||||||
|
}
|
||||||
|
#endif /* CONFIG_COMPAT_32BIT_TIME */
|
||||||
|
--
|
||||||
|
GitLab
|
||||||
|
|
||||||
|
From cdaa060153c4adf0a64d7bbf7e3ebba727c7e335 Mon Sep 17 00:00:00 2001
|
||||||
|
From: =?UTF-8?q?Andr=C3=A9=20Almeida?= <andrealmeid@collabora.com>
|
||||||
|
Date: Fri, 7 Feb 2020 23:28:02 -0300
|
||||||
|
Subject: [PATCH] futex: Add Proton compatibility code
|
||||||
|
|
||||||
|
PPA Note: This patch has been modified to build against 5.13
|
||||||
|
---
|
||||||
|
include/uapi/linux/futex.h | 2 +-
|
||||||
|
kernel/futex.c | 5 +++--
|
||||||
|
2 files changed, 4 insertions(+), 3 deletions(-)
|
||||||
|
|
||||||
|
diff --git a/include/uapi/linux/futex.h b/include/uapi/linux/futex.h
|
||||||
|
index 580001e89c6c..a3e760886b8e 100644
|
||||||
|
--- a/include/uapi/linux/futex.h
|
||||||
|
+++ b/include/uapi/linux/futex.h
|
||||||
|
@@ -21,7 +21,7 @@
|
||||||
|
#define FUTEX_WAIT_REQUEUE_PI 11
|
||||||
|
#define FUTEX_CMP_REQUEUE_PI 12
|
||||||
|
#define FUTEX_LOCK_PI2 13
|
||||||
|
-#define FUTEX_WAIT_MULTIPLE 14
|
||||||
|
+#define FUTEX_WAIT_MULTIPLE 31
|
||||||
|
|
||||||
|
#define FUTEX_PRIVATE_FLAG 128
|
||||||
|
#define FUTEX_CLOCK_REALTIME 256
|
||||||
|
diff --git a/kernel/futex.c b/kernel/futex.c
|
||||||
|
index b28a6abbdefd..5b547c911b92 100644
|
||||||
|
--- a/kernel/futex.c
|
||||||
|
+++ b/kernel/futex.c
|
||||||
|
@@ -4038,7 +4038,7 @@
|
||||||
|
return -EINVAL;
|
||||||
|
|
||||||
|
*t = timespec64_to_ktime(*ts);
|
||||||
|
- if (cmd == FUTEX_WAIT)
|
||||||
|
+ if (cmd == FUTEX_WAIT || cmd == FUTEX_WAIT_MULTIPLE)
|
||||||
|
*t = ktime_add_safe(ktime_get(), *t);
|
||||||
|
else if (cmd != FUTEX_LOCK_PI && !(op & FUTEX_CLOCK_REALTIME))
|
||||||
|
*t = timens_ktime_to_host(CLOCK_MONOTONIC, *t);
|
||||||
|
@@ -4248,6 +4248,7 @@ COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid,
|
||||||
|
*/
|
||||||
|
struct compat_futex_wait_block {
|
||||||
|
compat_uptr_t uaddr;
|
||||||
|
+ __u32 pad;
|
||||||
|
__u32 val;
|
||||||
|
__u32 bitset;
|
||||||
|
};
|
||||||
|
--
|
||||||
|
GitLab
|
||||||
|
|
||||||
Reference in New Issue
Block a user