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2017-11-12x86/intel_rdt: Fix a silent failure when writing zero value schemataXiaochen Shen
Writing an invalid schemata with no domain values (e.g., "(L3|MB):"), results in a silent failure, i.e. the last_cmd_status returns OK, Check for an empty value and set the result string with a proper error message and return -EINVAL. Before the fix: # mkdir /sys/fs/resctrl/p1 # echo "L3:" > /sys/fs/resctrl/p1/schemata (silent failure) # cat /sys/fs/resctrl/info/last_cmd_status ok # echo "MB:" > /sys/fs/resctrl/p1/schemata (silent failure) # cat /sys/fs/resctrl/info/last_cmd_status ok After the fix: # mkdir /sys/fs/resctrl/p1 # echo "L3:" > /sys/fs/resctrl/p1/schemata -bash: echo: write error: Invalid argument # cat /sys/fs/resctrl/info/last_cmd_status Missing 'L3' value # echo "MB:" > /sys/fs/resctrl/p1/schemata -bash: echo: write error: Invalid argument # cat /sys/fs/resctrl/info/last_cmd_status Missing 'MB' value [ Tony: This is an unintended side effect of the patch earlier to allow the user to just write the value they want to change. While allowing user to specify less than all of the values, it also allows an empty value. ] Fixes: c4026b7b95a4 ("x86/intel_rdt: Implement "update" mode when writing schemata file") Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Link: https://lkml.kernel.org/r/20171110191624.20280-1-tony.luck@intel.com
2017-11-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2017-11-12powerpc/vas: Add support for user receive windowSukadev Bhattiprolu
Add support for user space receive window (for the Fast thread-wakeup coprocessor type) Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: Define vas_win_id()Sukadev Bhattiprolu
Define an interface to return a system-wide unique id for a given VAS window. The vas_win_id() will be used in a follow-on patch to generate an unique handle for a user space receive window. Applications can use this handle to pair send and receive windows for fast thread-wakeup. The hardware refers to this system-wide unique id as a Partition Send Window ID which is expected to be used during fault handling. Hence the "pswid" in the function names. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: Define vas_win_paste_addr()Sukadev Bhattiprolu
Define an interface that the NX drivers can use to find the physical paste address of a send window. This interface is expected to be used with the mmap() operation of the NX driver's device. i.e the user space process can use driver's mmap() operation to map the send window's paste address into their address space and then use copy and paste instructions to submit the CRBs to the NX engine. Note that kernel drivers will use vas_paste_crb() directly and don't need this interface. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc: Define set_thread_uses_vas()Sukadev Bhattiprolu
A CP_ABORT instruction is required in processes that have mapped a VAS "paste address" with the intention of using COPY/PASTE instructions. But since CP_ABORT is expensive, we want to restrict it to only processes that use/intend to use COPY/PASTE. Define an interface, set_thread_uses_vas(), that VAS can use to indicate that the current process opened a send window. During context switch, issue CP_ABORT only for processes that have the flag set. Thanks for input from Nick Piggin, Michael Ellerman. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> [mpe: Fix to not use new_thread after _switch() returns] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc: Add support for setting SPRN_TIDRSukadev Bhattiprolu
We need the SPRN_TIDR to be set for use with fast thread-wakeup (core- to-core wakeup) and also with CAPI. Each thread in a process needs to have a unique id within the process. But for now, we assign globally unique thread ids to all threads in the system. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com> Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> [mpe: Simplify tidr clearing on fork() and ctx switch code] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: Export HVWC to debugfsSukadev Bhattiprolu
Export the VAS Window context information to debugfs. We need to hold a mutex when closing the window to prevent a race with the debugfs read(). Rather than introduce a per-instance mutex, we use the global vas_mutex for now, since it is not heavily contended. The window->cop field is only relevant to a receive window so we were not setting it for a send window (which is is paired to a receive window anyway). But to simplify reporting in debugfs, set the 'cop' field for the send window also. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas, nx-842: Define and use chip_to_vas_id()Sukadev Bhattiprolu
Define a helper, chip_to_vas_id() to map a given chip id to corresponding vas id. Normally, callers of vas_rx_win_open() and vas_tx_win_open() want the VAS window to be on the same chip where the calling thread is executing. These callers can pass in -1 for the VAS id. This interface will be useful if a thread running on one chip wants to open a window on another chip (like the NX-842 driver does during start up). Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: Create cpu to vas id mappingSukadev Bhattiprolu
Create a cpu to vasid mapping so callers can specify -1 instead of trying to find a VAS id. Changelog[v2] [Michael Ellerman] Use per-cpu variables to simplify code. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: poll for return of window creditsSukadev Bhattiprolu
Normally, the NX driver waits for the CRBs to be processed before closing the window. But it is better to ensure that the credits are returned before the window gets reassigned later. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: Save configured window creditsSukadev Bhattiprolu
Save the configured max window credits for a window in the vas_window structure. We will need this when polling for return of window credits. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: Reduce polling interval for busy stateSukadev Bhattiprolu
A VAS window is normally in "busy" state for only a short duration. Reduce the time we wait for the window to go to "not-busy" state to speed-up vas_win_close() a bit. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: Use helper to unpin/close windowSukadev Bhattiprolu
Use a helper to have the hardware unpin and mark a window closed. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: Drop poll_window_cast_out().Sukadev Bhattiprolu
Polling for window cast out is listed in the spec, but turns out that it is not strictly necessary and slows down window close. Making it a stub for now. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: Cleanup some debug codeSukadev Bhattiprolu
Clean up vas.h and the debug code around ifdef vas_debug. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: Validate window creditsSukadev Bhattiprolu
NX-842, the only user of VAS, sets the window credits to default values but VAS should check the credits against the possible max values. The VAS_WCREDS_MIN is not needed and can be dropped. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12powerpc/vas: init missing fields from [rt]xattrSukadev Bhattiprolu
Initialize a few missing window context fields from the window attributes specified by the caller. These fields are currently set to their default values by the caller (NX-842), but would be good to apply them anyway. Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-11bpf: Revert bpf_overrid_function() helper changes.David S. Miller
NACK'd by x86 maintainer. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-11bpf: add a bpf_override_function helperJosef Bacik
Error injection is sloppy and very ad-hoc. BPF could fill this niche perfectly with it's kprobe functionality. We could make sure errors are only triggered in specific call chains that we care about with very specific situations. Accomplish this with the bpf_override_funciton helper. This will modify the probe'd callers return value to the specified value and set the PC to an override function that simply returns, bypassing the originally probed function. This gives us a nice clean way to implement systematic error injection for all of our code paths. Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Josef Bacik <jbacik@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-10xtensa/simdisk: fix compile errorChristoph Hellwig
Fixes: d004a5e7d4dd ("block: remove __bio_kmap_atomic") Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10block: remove __bio_kmap_atomicChristoph Hellwig
This helper doesn't buy us much over calling kmap_atomic directly. In fact in the only caller it does a bit of useless work as the caller already has the bvec at hand, and said caller would even buggy for a multi-segment bio due to the use of this helper. So just remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10MIPS: Fix odd fp register warnings with MIPS64r2James Hogan
Building 32-bit MIPS64r2 kernels produces warnings like the following on certain toolchains (such as GNU assembler 2.24.90, but not GNU assembler 2.28.51) since commit 22b8ba765a72 ("MIPS: Fix MIPS64 FP save/restore on 32-bit kernels"), due to the exposure of fpu_save_16odd from fpu_save_double and fpu_restore_16odd from fpu_restore_double: arch/mips/kernel/r4k_fpu.S:47: Warning: float register should be even, was 1 ... arch/mips/kernel/r4k_fpu.S:59: Warning: float register should be even, was 1 ... This appears to be because .set mips64r2 does not change the FPU ABI to 64-bit when -march=mips64r2 (or e.g. -march=xlp) is provided on the command line on that toolchain, from the default FPU ABI of 32-bit due to the -mabi=32. This makes access to the odd FPU registers invalid. Fix by explicitly changing the FPU ABI with .set fp=64 directives in fpu_save_16odd and fpu_restore_16odd, and moving the undefine of fp up in asmmacro.h so fp doesn't turn into $30. Fixes: 22b8ba765a72 ("MIPS: Fix MIPS64 FP save/restore on 32-bit kernels") Signed-off-by: James Hogan <jhogan@kernel.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: linux-mips@linux-mips.org Cc: <stable@vger.kernel.org> # 4.0+: 22b8ba765a72: MIPS: Fix MIPS64 FP save/restore on 32-bit kernels Cc: <stable@vger.kernel.org> # 4.0+ Patchwork: https://patchwork.linux-mips.org/patch/17656/
2017-11-10Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fix from Radim Krčmář: "Fix PPC HV host crash that can occur as a result of resizing the guest hashed page table" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: PPC: Book3S HV: Fix exclusion between HPT resizing and other HPT updates
2017-11-10Merge tag 'mips_fixes_4.14_2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips Pull MIPS fixes from James Hogan: "A final few MIPS fixes for 4.14: - fix BMIPS NULL pointer dereference (4.7) - fix AR7 early GPIO init allocation failure (3.19) - fix dead serial output on certain AR7 platforms (2.6.35)" * tag 'mips_fixes_4.14_2' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips: MIPS: AR7: Ensure that serial ports are properly set up MIPS: AR7: Defer registration of GPIO MIPS: BMIPS: Fix missing cbr address
2017-11-10Revert "x86: CPU: Fix up "cpu MHz" in /proc/cpuinfo"Linus Torvalds
This reverts commit 941f5f0f6ef5338814145cf2b813cf1f98873e2f. Sadly, it turns out that we really can't just do the cross-CPU IPI to all CPU's to get their proper frequencies, because it's much too expensive on systems with lots of cores. So we'll have to revert this for now, and revisit it using a smarter model (probably doing one system-wide IPI at open time, and doing all the frequency calculations in parallel). Reported-by: WANG Chao <chao.wang@ucloud.cn> Reported-by: Ingo Molnar <mingo@kernel.org> Cc: Rafael J Wysocki <rafael.j.wysocki@intel.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-10s390/noexec: execute kexec datamover without DATHeiko Carstens
Rebooting into a new kernel with kexec fails (system dies) if tried on a machine that has no-execute support. Reason for this is that the so called datamover code gets executed with DAT on (MMU is active) and the page that contains the datamover is marked as non-executable. Therefore when branching into the datamover an unexpected program check happens and afterwards the machine is dead. This can be simply avoided by disabling DAT, which also disables any no-execute checks, just before the datamover gets executed. In fact the first thing done by the datamover is to disable DAT. The code in the datamover that disables DAT can be removed as well. Thanks to Michael Holzheu and Gerald Schaefer for tracking this down. Reviewed-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Fixes: 57d7f939e7bd ("s390: add no-execute support") Cc: <stable@vger.kernel.org> # v4.11+ Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2017-11-10s390: fix transactional execution control register handlingHeiko Carstens
Dan Horák reported the following crash related to transactional execution: User process fault: interruption code 0013 ilc:3 in libpthread-2.26.so[3ff93c00000+1b000] CPU: 2 PID: 1 Comm: /init Not tainted 4.13.4-300.fc27.s390x #1 Hardware name: IBM 2827 H43 400 (z/VM 6.4.0) task: 00000000fafc8000 task.stack: 00000000fafc4000 User PSW : 0705200180000000 000003ff93c14e70 R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:1 AS:0 CC:2 PM:0 RI:0 EA:3 User GPRS: 0000000000000077 000003ff00000000 000003ff93144d48 000003ff93144d5e 0000000000000000 0000000000000002 0000000000000000 000003ff00000000 0000000000000000 0000000000000418 0000000000000000 000003ffcc9fe770 000003ff93d28f50 000003ff9310acf0 000003ff92b0319a 000003ffcc9fe6d0 User Code: 000003ff93c14e62: 60e0b030 std %f14,48(%r11) 000003ff93c14e66: 60f0b038 std %f15,56(%r11) #000003ff93c14e6a: e5600000ff0e tbegin 0,65294 >000003ff93c14e70: a7740006 brc 7,3ff93c14e7c 000003ff93c14e74: a7080000 lhi %r0,0 000003ff93c14e78: a7f40023 brc 15,3ff93c14ebe 000003ff93c14e7c: b2220000 ipm %r0 000003ff93c14e80: 8800001c srl %r0,28 There are several bugs with control register handling with respect to transactional execution: - on task switch update_per_regs() is only called if the next task has an mm (is not a kernel thread). This however is incorrect. This breaks e.g. for user mode helper handling, where the kernel creates a kernel thread and then execve's a user space program. Control register contents related to transactional execution won't be updated on execve. If the previous task ran with transactional execution disabled then the new task will also run with transactional execution disabled, which is incorrect. Therefore call update_per_regs() unconditionally within switch_to(). - on startup the transactional execution facility is not enabled for the idle thread. This is not really a bug, but an inconsistency to other facilities. Therefore enable the facility if it is available. - on fork the new thread's per_flags field is not cleared. This means that a child process inherits the PER_FLAG_NO_TE flag. This flag can be set with a ptrace request to disable transactional execution for the current process. It should not be inherited by new child processes in order to be consistent with the handling of all other PER related debugging options. Therefore clear the per_flags field in copy_thread_tls(). Reported-and-tested-by: Dan Horák <dan@danny.cz> Fixes: d35339a42dd1 ("s390: add support for transactional memory") Cc: <stable@vger.kernel.org> # v3.7+ Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2017-11-10s390/bpf: take advantage of stack_depth trackingMichael Holzheu
Make use of the "stack_depth" tracking feature introduced with commit 8726679a0fa31 ("bpf: teach verifier to track stack depth") for the s390 JIT, so that stack usage can be reduced. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2017-11-10ARM: dts: Add remote-wakeup-connected for omap OHCITony Lindgren
Add remote-wakeup-connected for omap OHCI as that's needed by ohci-platform driver. Cc: devicetree@vger.kernel.org Cc: Hans de Goede <hdegoede@redhat.com> Cc: Rob Herring <robh@kernel.org> Cc: Sebastian Reichel <sebastian.reichel@collabora.co.uk> Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Acked-by: Roger Quadros <rogerq@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2017-11-10ARM: dts: am33xx: Add missing #phy-cells to ti,am335x-usb-phyRob Herring
"ti,am335x-usb-phy" is using the phy binding, but is missing #phy-cells property. Fixes the following warning in TI dts files: Warning (phys_property): Missing property '#phy-cells' in node ... Signed-off-by: Rob Herring <robh@kernel.org> Cc: "Benoît Cousson" <bcousson@baylibre.com> Cc: Tony Lindgren <tony@atomide.com> Cc: linux-omap@vger.kernel.org Signed-off-by: Tony Lindgren <tony@atomide.com>
2017-11-10ARM: dts: omap: Add missing #phy-cells to usb-nop-xceivRob Herring
"usb-nop-xceiv" is using the phy binding, but is missing #phy-cells property. This is probably because the binding was the precursor to the phy binding. Fixes the following warning in OMAP dts files: Warning (phys_property): Missing property '#phy-cells' in node ... Signed-off-by: Rob Herring <robh@kernel.org> Cc: "Benoît Cousson" <bcousson@baylibre.com> Cc: Tony Lindgren <tony@atomide.com> Cc: Enric Balletbo i Serra <eballetbo@gmail.com> Cc: Javier Martinez Canillas <javier@dowhile0.org> Cc: linux-omap@vger.kernel.org Signed-off-by: Tony Lindgren <tony@atomide.com>
2017-11-10ARM: sa1100: simpad: Correct I2C GPIO offsetsLinus Walleij
Arnd reported the following build bug bug: In file included from arch/arm/mach-sa1100/simpad.c:20:0: arch/arm/mach-sa1100/include/mach/SA-1100.h:1118:18: error: large integer implicitly truncated to unsigned type [-Werror=overflow] (0x00000001 << (Nb)) ^ include/linux/gpio/machine.h:56:16: note: in definition of macro 'GPIO_LOOKUP_IDX' .chip_hwnum = _chip_hwnum, ^~~~~~~~~~~ arch/arm/mach-sa1100/include/mach/SA-1100.h:1140:21: note: in expansion of macro 'GPIO_GPIO' ^~~~~~~~~ arch/arm/mach-sa1100/simpad.c:331:27: note: in expansion of macro 'GPIO_GPIO21' GPIO_LOOKUP_IDX("gpio", GPIO_GPIO21, NULL, 0, This is what happened: commit b2e63555592f81331c8da3afaa607d8cf83e8138 "i2c: gpio: Convert to use descriptors" commit 4d0ce62c0a02e41a65cfdcfe277f5be430edc371 "i2c: gpio: Augment all boardfiles to use open drain" together uncovered an old bug in the Simpad board file: as theGPIO_LOOKUP_IDX() encodes GPIO offsets on gpiochips in an u16 (see <linux/gpio/machine.h>) these GPIO "numbers" does not fit, since in arch/arm/mach-sa1100/include/mach/SA-1100.h it is defined as: #define GPIO_GPIO(Nb) (0x00000001 << (Nb)) (...) #define GPIO_GPIO21 GPIO_GPIO(21) /* GPIO [21] */ This is however provably wrong, since the i2c-gpio driver uses proper GPIO numbers, albeit earlier from the global number space, whereas this GPIO_GPIO21 is the local line offset in the GPIO register, which is used in other code but certainly not in the gpiolib GPIO driver in drivers/gpio/gpio-sa1100.c, which has code like this: static void sa1100_gpio_set(struct gpio_chip *chip, unsigned offset, int value) { int reg = value ? R_GPSR : R_GPCR; writel_relaxed(BIT(offset), sa1100_gpio_chip(chip)->membase + reg); } So far everything however compiled fine as an unsigned int was used to pass the GPIO numbers in struct i2c_gpio_platform_data. We can trace the actual error back to commit dbd406f9d0a1d33a1303eb75cbe3f9435513d339 "ARM: 7025/1: simpad: add GPIO based device definitions." This added the i2c_gpio with the wrong offsets. This commit was before the SA1100 was converted to use the gpiolib, but as can be seen from the contemporary gpio.c in mach-sa1100, it was already using: static int sa1100_gpio_get(struct gpio_chip *chip, unsigned offset) { return GPLR & GPIO_GPIO(offset); } And GPIO_GPIO() is essentially the BIT() macro. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-10locking/x86: Use LOCK ADD for smp_mb() instead of MFENCEMichael S. Tsirkin
MFENCE appears to be way slower than a locked instruction - let's use LOCK ADD unconditionally, as we always did on old 32-bit. Performance testing results: perf stat -r 10 -- ./virtio_ring_0_9 --sleep --host-affinity 0 --guest-affinity 0 Before: 0.922565990 seconds time elapsed ( +- 1.15% ) After: 0.578667024 seconds time elapsed ( +- 1.21% ) i.e. about ~60% faster. Just poking at SP would be the most natural, but if we then read the value from SP, we get a false dependency which will slow us down. This was noted in this article: http://shipilev.net/blog/2014/on-the-fence-with-dependencies/ And is easy to reproduce by sticking a barrier in a small non-inline function. So let's use a negative offset - which avoids this problem since we build with the red zone disabled. For userspace, use an address just below the redzone. The one difference between LOCK ADD and MFENCE is that LOCK ADD does not affect CLFLUSH, previous patches converted all uses of CLFLUSH to call mb(), such that changes to smp_mb() won't affect it. Update mb/rmb/wmb() on 32-bit to use the negative offset, too, for consistency. As a follow-up, it might be worth considering switching users of CLFLUSH to another API (e.g. clflush_mb()?) - we will then be able to convert mb() to smp_mb() again. Also arguably, GCC should switch to use LOCK ADD for __sync_synchronize(). This might be worth pursuing separately. Suggested-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: qemu-devel@nongnu.org Cc: virtualization@lists.linux-foundation.org Link: http://lkml.kernel.org/r/1509118355-4890-1-git-send-email-mst@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-10powerpc/64: Set DSCR default initially from SPRNicholas Piggin
Take the DSCR value set by firmware as the dscr_default value, rather than zero. POWER9 recommends DSCR default to a non-zero value. Signed-off-by: From: Nicholas Piggin <npiggin@gmail.com> [mpe: Make record_spr_defaults() __init] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10powerpc/powernv: Avoid waiting for secondary hold spinloop with OPALNicholas Piggin
OPAL boot does not insert secondaries at 0x60 to wait at the secondary hold spinloop. Instead they are started later, and inserted at generic_secondary_smp_init(), which is after the secondary hold spinloop. Avoid waiting on this spinloop when booting with OPAL firmware. This wait always times out that case. This saves 100ms boot time on powernv, and 10s of seconds of real time when booting on the simulator in SMP. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10powerpc/64s/radix: Improve TLB flushing for page table freeingNicholas Piggin
Unmaps that free page tables always flush the entire PID, which is sub-optimal. Provide TLB range flushing with an additional PWC flush that can be use for va range invalidations with PWC flush. Time to munmap N pages of memory including last level page table teardown (after mmap, touch), local invalidate: N 1 2 4 8 16 32 64 vanilla 3.2us 3.3us 3.4us 3.6us 4.1us 5.2us 7.2us patched 1.4us 1.5us 1.7us 1.9us 2.6us 3.7us 6.2us Global invalidate: N 1 2 4 8 16 32 64 vanilla 2.2us 2.3us 2.4us 2.6us 3.2us 4.1us 6.2us patched 2.1us 2.5us 3.4us 5.2us 8.7us 15.7us 6.2us Local invalidates get much better across the board. Global ones have the same issue where multiple tlbies for va flush do get slower than the single tlbie to invalidate the PID. None of this test captures the TLB benefits of avoiding killing everything. Global gets worse, but it is brought in to line with global invalidate for munmap()s that do not free page tables. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10powerpc/64s/radix: Introduce local single page ceiling for TLB range flushNicholas Piggin
The single page flush ceiling is the cut-off point at which we switch from invalidating individual pages, to invalidating the entire process address space in response to a range flush. Introduce a local variant of this heuristic because local and global tlbie have significantly different properties: - Local tlbiel requires 128 instructions to invalidate a PID, global tlbie only 1 instruction. - Global tlbie instructions are expensive broadcast operations. The local ceiling has been made much higher, 2x the number of instructions required to invalidate the entire PID (i.e., 256 pages). Time to mprotect N pages of memory (after mmap, touch), local invalidate: N 32 34 64 128 256 512 vanilla 7.4us 9.0us 14.6us 26.4us 50.2us 98.3us patched 7.4us 7.8us 13.8us 26.4us 51.9us 98.3us The behaviour of both is identical at N=32 and N=512. Between there, the vanilla kernel does a PID invalidate and the patched kernel does a va range invalidate. At N=128, these require the same number of tlbiel instructions, so the patched version can be sen to be cheaper when < 128, and more expensive when > 128. However this does not well capture the cost of invalidated TLB. The additional cost at 256 pages does not seem prohibitive. It may be the case that increasing the limit further would continue to be beneficial to avoid invalidating all of the process's TLB entries. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10powerpc/64s/radix: Optimize flush_tlb_rangeNicholas Piggin
Currently for radix, flush_tlb_range flushes the entire PID, because the Linux mm code does not tell us about page size here for THP vs regular pages. This is quite sub-optimal for small mremap / mprotect / change_protection. So implement va range flushes with two flush passes, one for each page size (regular and THP). The second flush has an order of matnitude fewer tlbie instructions than the first, so it is a relatively small additional cost. There is still room for improvement here with some changes to generic APIs, particularly if there are mostly THP pages to be invalidated, the small page flushes could be reduced. Time to mprotect 1 page of memory (after mmap, touch): vanilla 2.9us 1.8us patched 1.2us 1.6us Time to mprotect 30 pages of memory (after mmap, touch): vanilla 8.2us 7.2us patched 6.9us 17.9us Time to mprotect 34 pages of memory (after mmap, touch): vanilla 9.1us 8.0us patched 9.0us 8.0us 34 pages is the point at which the invalidation switches from va to entire PID, which tlbie can do in a single instruction. This is why in the case of 30 pages, the new code runs slower for this test. This is a deliberate tradeoff already present in the unmap and THP promotion code, the idea is that the benefit from avoiding flushing entire TLB for this PID on all threads in the system. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10powerpc/64s/radix: Implement _tlbie(l)_va_range flush functionsNicholas Piggin
Move the barriers and range iteration down into the _tlbie* level, which improves readability. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10powerpc/64s/radix: Optimize TLB range flush barriersNicholas Piggin
Short range flushes issue a sequences of tlbie(l) instructions for individual effective addresses. These do not all require individual barrier sequences, only one covering all tlbie(l) instructions. Commit f7327e0ba3 ("powerpc/mm/radix: Remove unnecessary ptesync") made a similar optimization for tlbiel for PID flushing. For tlbie, the ISA says: The tlbsync instruction provides an ordering function for the effects of all tlbie instructions executed by the thread executing the tlbsync instruction, with respect to the memory barrier created by a subsequent ptesync instruction executed by the same thread. Time to munmap 30 pages of memory (after mmap, touch): local global vanilla 10.9us 22.3us patched 3.4us 14.4us Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-10Merge branch 'fixes' into nextMichael Ellerman
We have some dependencies & conflicts between patches in fixes and things to go in next, both in the radix TLB flush code and the IMC PMU driver. So merge fixes into next.
2017-11-10x86/virt/xen: Use guest_late_init to detect Xen PVH guestJuergen Gross
In case we are booted via the default boot entry by a generic loader like grub or OVMF it is necessary to distinguish between a HVM guest with a device model supporting legacy devices and a PVH guest without device model. PVH guests will always have x86_platform.legacy.no_vga set and x86_platform.legacy.rtc cleared, while both won't be true for HVM guests. Test for both conditions in the guest_late_init hook and set xen_pvh to true if they are met. Move some of the early PVH initializations to the new hook in order to avoid duplicated code. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: boris.ostrovsky@oracle.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20171109132739.23465-6-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-10x86/virt, x86/platform: Add ->guest_late_init() callback to hypervisor_x86 ↵Juergen Gross
structure Add a new guest_late_init callback to the hypervisor_x86 structure. It will replace the current kvm_guest_init() call which is changed to make use of the new callback. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: kvm@vger.kernel.org Cc: rkrcmar@redhat.com Link: http://lkml.kernel.org/r/20171109132739.23465-5-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-10x86/virt, x86/acpi: Add test for ACPI_FADT_NO_VGAJuergen Gross
Add a test for ACPI_FADT_NO_VGA when scanning the FADT and set the new flag x86_platform.legacy.no_vga accordingly. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: len.brown@intel.com Cc: linux-pm@vger.kernel.org Cc: pavel@ucw.cz Cc: rjw@rjwysocki.net Link: http://lkml.kernel.org/r/20171109132739.23465-4-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-10x86/virt: Add enum for hypervisors to replace x86_hyperJuergen Gross
The x86_hyper pointer is only used for checking whether a virtual device is supporting the hypervisor the system is running on. Use an enum for that purpose instead and drop the x86_hyper pointer. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Xavier Deguillard <xdeguillard@vmware.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: akataria@vmware.com Cc: arnd@arndb.de Cc: boris.ostrovsky@oracle.com Cc: devel@linuxdriverproject.org Cc: dmitry.torokhov@gmail.com Cc: gregkh@linuxfoundation.org Cc: haiyangz@microsoft.com Cc: kvm@vger.kernel.org Cc: kys@microsoft.com Cc: linux-graphics-maintainer@vmware.com Cc: linux-input@vger.kernel.org Cc: moltmann@vmware.com Cc: pbonzini@redhat.com Cc: pv-drivers@vmware.com Cc: rkrcmar@redhat.com Cc: sthemmin@microsoft.com Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20171109132739.23465-3-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-10x86/virt, x86/platform: Merge 'struct x86_hyper' into 'struct x86_platform' ↵Juergen Gross
and 'struct x86_init' Instead of x86_hyper being either NULL on bare metal or a pointer to a struct hypervisor_x86 in case of the kernel running as a guest merge the struct into x86_platform and x86_init. This will remove the need for wrappers making it hard to find out what is being called. With dummy functions added for all callbacks testing for a NULL function pointer can be removed, too. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: akataria@vmware.com Cc: boris.ostrovsky@oracle.com Cc: devel@linuxdriverproject.org Cc: haiyangz@microsoft.com Cc: kvm@vger.kernel.org Cc: kys@microsoft.com Cc: pbonzini@redhat.com Cc: rkrcmar@redhat.com Cc: rusty@rustcorp.com.au Cc: sthemmin@microsoft.com Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20171109132739.23465-2-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-10x86/tsc: Mark cyc2ns_init() and detect_art() __initDou Liyang
These two functions are only called by tsc_init(), which is an __init function during boot time, so mark them __init as well. Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1510135792-17429-1-git-send-email-douly.fnst@cn.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-10KVM: arm/arm64: GICv4: Add init/teardown of the per-VM vPE irq domainMarc Zyngier
In order to control the GICv4 view of virtual CPUs, we rely on an irqdomain allocated for that purpose. Let's add a couple of helpers to that effect. At the same time, the vgic data structures gain new fields to track all this... erm... wonderful stuff. The way we hook into the vgic init is slightly convoluted. We need the vgic to be initialized (in order to guarantee that the number of vcpus is now fixed), and we must have a vITS (otherwise this is all very pointless). So we end-up calling the init from both vgic_init and vgic_its_create. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-10Merge branch 'linus' into x86/platform, to refresh the branchIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>