summaryrefslogtreecommitdiff
path: root/arch/powerpc
AgeCommit message (Collapse)Author
2014-09-25powerpc: Emulate icbi, mcrf and conditional-trap instructionsPaul Mackerras
This extends the instruction emulation done by analyse_instr() and emulate_step() to handle a few more instructions that are found in the kernel. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Split out instruction analysis part of emulate_step()Paul Mackerras
This splits out the instruction analysis part of emulate_step() into a separate analyse_instr() function, which decodes the instruction, but doesn't execute any load or store instructions. It does execute integer instructions and branches which can be executed purely by updating register values in the pt_regs struct. For other instructions, it returns the instruction type and other details in a new instruction_op struct. emulate_step() then uses that information to execute loads, stores, cache operations, mfmsr, mtmsr[d], and (on 64-bit) sc instructions. The reason for doing this is so that the KVM code can use it instead of having its own separate instruction emulation code. Possibly the alignment interrupt handler could also use this. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Check flat device tree version at bootMichael Ellerman
In commit e6a6928c3ea1 "of/fdt: Convert FDT functions to use libfdt", the kernel stopped supporting old flat device tree formats. The minimum supported version is now 0x10. There was a checking function added, early_init_dt_verify(), but it's not called on powerpc. The result is, if you boot with an old flat device tree, the kernel will fail to parse it correctly, think you have no memory etc. and hilarity ensues. We can't really fix it, but we can at least catch the fact that the device tree is in an unsupported format and panic(). We can't call BUG(), it's too early. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc/powernv: Don't call generic code on offline cpusPaul Mackerras
On PowerNV platforms, when a CPU is offline, we put it into nap mode. It's possible that the CPU wakes up from nap mode while it is still offline due to a stray IPI. A misdirected device interrupt could also potentially cause it to wake up. In that circumstance, we need to clear the interrupt so that the CPU can go back to nap mode. In the past the clearing of the interrupt was accomplished by briefly enabling interrupts and allowing the normal interrupt handling code (do_IRQ() etc.) to handle the interrupt. This has the problem that this code calls irq_enter() and irq_exit(), which call functions such as account_system_vtime() which use RCU internally. Use of RCU is not permitted on offline CPUs and will trigger errors if RCU checking is enabled. To avoid calling into any generic code which might use RCU, we adopt a different method of clearing interrupts on offline CPUs. Since we are on the PowerNV platform, we know that the system interrupt controller is a XICS being driven directly (i.e. not via hcalls) by the kernel. Hence this adds a new icp_native_flush_interrupt() function to the native-mode XICS driver and arranges to call that when an offline CPU is woken from nap. This new function reads the interrupt from the XICS. If it is an IPI, it clears the IPI; if it is a device interrupt, it prints a warning and disables the source. Then it does the end-of-interrupt processing for the interrupt. The other thing that briefly enabling interrupts did was to check and clear the irq_happened flag in this CPU's PACA. Therefore, after flushing the interrupt from the XICS, we also clear all bits except the PACA_IRQ_HARD_DIS (interrupts are hard disabled) bit from the irq_happened flag. The PACA_IRQ_HARD_DIS flag is set by power7_nap() and is left set to indicate that interrupts are hard disabled. This means we then have to ignore that flag in power7_nap(), which is reasonable since it doesn't indicate that any interrupt event needs servicing. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Use CONFIG_ARCH_HAS_FAST_MULTIPLIERAnton Blanchard
I ran some tests to compare hash_64 using shifts and multiplies. The results: POWER6: ~2x slower POWER7: ~2x faster POWER8: ~2x faster Now we have a proper config option, select CONFIG_ARCH_HAS_FAST_MULTIPLIER on POWER7 and POWER8. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Add POWER8 CPU selectionAnton Blanchard
This allows the user to build a kernel targeted at POWER8 (ie gcc -mcpu=power8). Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25pseries: Fix endian issues in cpu hot-removalThomas Falcon
When removing a cpu, this patch makes sure that values gotten from or passed to firmware are in the correct endian format. Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25pseries: Fix endian issues in onlining cpu threadsThomas Falcon
The ibm,ppc-interrupt-server#s property is in big endian format. These values need to be converted when used by little endian architectures. Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Simplify symbol check in prom_init_check.shAndreas Schwab
Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: make of_device_ids constUwe Kleine-König
of_device_ids (i.e. compatible strings and the respective data) are not supposed to change at runtime. All functions working with of_device_ids provided by <linux/of.h> work with const of_device_ids. This allows to mark all struct of_device_id const, too. While touching these line also put the __init annotation at the right position where necessary. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc/jump_label: use HAVE_JUMP_LABEL?Zhouyi Zhou
CONFIG_JUMP_LABEL doesn't ensure HAVE_JUMP_LABEL, if it is not the case use maintainers's own mutex to guard the modification of global values. Signed-off-by: Zhouyi Zhou <yizhouzhou@ict.ac.cn> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Export dcr_ind_lock to fix build errorPranith Kumar
Fix build error caused by missing export: ERROR: "dcr_ind_lock" [drivers/net/ethernet/ibm/emac/ibm_emac.ko] undefined! Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Move htab_remove_mapping function prototype into header fileAnton Blanchard
A recent patch added a function prototype for htab_remove_mapping in c code. Fix it. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Remove stale function prototypesAnton Blanchard
There were a number of prototypes for functions that no longer exist. Remove them. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Ensure global functions include their prototypeAnton Blanchard
Fix a number of places where global functions were not including their prototype. This ensures the prototype and the function match. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Make a bunch of things staticAnton Blanchard
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Separate ppc32 symbol exports into ppc_ksyms_32.cAnton Blanchard
Simplify things considerably by moving all the ppc32 specific symbol exports into its own file. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Move lib symbol exports into arch/powerpc/lib/ppc_ksyms.cAnton Blanchard
Move the lib symbol exports closer to their function definitions Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Remove unused 32bit symbol exportsAnton Blanchard
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Move more symbol exports next to function definitionsAnton Blanchard
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Move via-cuda symbol exports next to function definitionsAnton Blanchard
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Move adb symbol exports next to function definitionsAnton Blanchard
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc/powernv: Check OPAL dump calls exist before usingMichael Neuling
Check that the OPAL_DUMP_READ token exists before initalising the elog infrastructure. This avoids littering the OPAL console with: "OPAL: Called with bad token 91" Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc/powernv: Check OPAL elog calls exist before usingMichael Neuling
Check that the OPAL_ELOG_READ token exists before initalising the elog infrastructure. This avoids littering the OPAL console with: "OPAL: Called with bad token 74" Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc/powernv: Check OPAL RTC calls exists before usingMichael Neuling
Check that the OPAL_RTC_READ token exists before we use the OPAL RTC. Refactors the code a little to merge error paths. This avoids littering the OPAL console with: "OPAL: Called with bad token 3". Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc/powernv: Add OPAL check token callMichael Neuling
Currently there is no way to generically check if an OPAL call exists or not from the host kernel. This adds an OPAL call opal_check_token() which tells you if the given token is present in OPAL or not. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc: Fix build error with CONFIG_PCI=nPranith Kumar
Fix ppc 32 build failure as reported here: http://kisskb.ellerman.id.au/kisskb/buildresult/11663513/ The error is as follows: arch/powerpc/include/asm/floppy.h:142:20: error: 'isa_bridge_pcidev' undeclared (first use in this function) This is happening since floppy.o is enabled by BLK_DEV_FD which depends on ARCH_MAY_HAVE_PC_FDC which is in-turn enabled if PPC_PSERIES=n. The following commit changes the dependency so that ARCH_MAY_HAVE_PC_FDC is dependent exclusively on PCI since otherwise it will not compile. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> CC: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc/boot: Don't install zImage.* from make installTony Breeds
in commit 29f1aff2c (powerpc: Copy bootable images in the default install script) we changed to copying all the built boot targets based on the assumption that it's backwards compatible. It turns out that debian devived installkernel scripts will barf if not given exactly 4 args. This change reverts make install to just install the vmlinux (we can change the dfault in a seperate patch) and introduces a new make zInstall which works with a more flexible installkernel script. Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Tony Breeds <tony@bakeyournoodle.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25powerpc/powernv: Improve error messages in dump codeVasant Hegde
Presently we only support initiating Service Processor dump from host. Hence update sysfs message. Also update couple of other error/info messages. Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-23powerpc/pseries: Drop unnecessary continueHimangi Saraogi
Continue is not needed at the bottom of a loop. The Coccinelle semantic patch implementing this change is: @@ @@ for (...;...;...) { ... if (...) { ... - continue; } } Signed-off-by: Himangi Saraogi <himangi774@gmail.com> Acked-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-09powerpc: Wire up sys_seccomp(), sys_getrandom() and sys_memfd_create()Pranith Kumar
This patch wires up three new syscalls for powerpc. The three new syscalls are seccomp, getrandom and memfd_create. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
2014-09-09powerpc: Make CONFIG_FHANDLE=y for all 64 bit powerpc defconfigsCyril Bur
CONFIG_FHANDLE is a requirement for systemd and with the increasing uptake of systemd within distros it makes sense for 64 bit defconfigs to include it. Signed-off-by: Cyril Bur <cyril.bur@au1.ibm.com>
2014-09-09powerpc: use machine_subsys_initcall() for opal_hmi_handler_init()Li Zhong
As opal_message_init() uses machine_early_initcall(powernv, ), and opal_hmi_handler_init() depends on that early initcall, so it also needs use machine_* to check the machine_id. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
2014-09-09powerpc/perf: Fix ABIv2 kernel backtracesAnton Blanchard
ABIv2 kernels are failing to backtrace through the kernel. An example: 39.30% readseek2_proce [kernel.kallsyms] [k] find_get_entry | --- find_get_entry __GI___libc_read The problem is in valid_next_sp() where we check that the new stack pointer is at least STACK_FRAME_OVERHEAD below the previous one. ABIv1 has a minimum stack frame size of 112 bytes consisting of 48 bytes and 64 bytes of parameter save area. ABIv2 changes that to 32 bytes with no paramter save area. STACK_FRAME_OVERHEAD is in theory the minimum stack frame size, but we over 240 uses of it, some of which assume that it includes space for the parameter area. We need to work through all our stack defines and rationalise them but let's fix perf now by creating STACK_FRAME_MIN_SIZE and using in valid_next_sp(). This fixes the issue: 30.64% readseek2_proce [kernel.kallsyms] [k] find_get_entry | --- find_get_entry pagecache_get_page generic_file_read_iter new_sync_read vfs_read sys_read syscall_exit __GI___libc_read Cc: stable@vger.kernel.org # 3.16+ Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Anton Blanchard <anton@samba.org>
2014-09-09powerpc/pseries: Fix endian issues in memory hotplugThomas Falcon
Values acquired from Open Firmware are in 32-bit big endian format and need to be handled on little endian architectures. This patch ensures values are in cpu endian when hotplugging memory. Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
2014-09-06Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm fixes from Paolo Bonzini: "A smattering of bug fixes across most architectures" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: powerpc/kvm/cma: Fix panic introduces by signed shift operation KVM: s390/mm: Fix guest storage key corruption in ptep_set_access_flags KVM: s390/mm: Fix storage key corruption during swapping arm/arm64: KVM: Complete WFI/WFE instructions ARM/ARM64: KVM: Nuke Hyp-mode tlbs before enabling MMU KVM: s390/mm: try a cow on read only pages for key ops KVM: s390: Fix user triggerable bug in dead code
2014-09-03powerpc/kvm/cma: Fix panic introduces by signed shift operationLaurent Dufour
fc95ca7284bc54953165cba76c3228bd2cdb9591 introduces a memset in kvmppc_alloc_hpt since the general CMA doesn't clear the memory it allocates. However, the size argument passed to memset is computed from a signed value and its signed bit is extended by the cast the compiler is doing. This lead to extremely large size value when dealing with order value >= 31, and almost all the memory following the allocated space is cleaned. As a consequence, the system is panicing and may even fail spawning the kdump kernel. This fix makes use of an unsigned value for the memset's size argument to avoid sign extension. Among this fix, another shift operation which may lead to signed extended value too is also fixed. Cc: Alexey Kardashevskiy <aik@ozlabs.ru> Cc: Paul Mackerras <paulus@samba.org> Cc: Alexander Graf <agraf@suse.de> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-29kexec: remove CONFIG_KEXEC dependency on cryptoVivek Goyal
New system call depends on crypto. As it did not have a separate config option, CONFIG_KEXEC was modified to select CRYPTO and CRYPTO_SHA256. But now previous patch introduced a new config option for new syscall. So CONFIG_KEXEC does not require crypto. Remove that dependency. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Shaun Ruffell <sruffell@digium.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-19PC, KVM, CMA: Fix regression caused by wrong get_order() useAlexey Kardashevskiy
fc95ca7284bc54953165cba76c3228bd2cdb9591 claims that there is no functional change but this is not true as it calls get_order() (which takes bytes) where it should have called order_base_2() and the kernel stops on VM_BUG_ON(). This replaces get_order() with order_base_2() (round-up version of ilog2). Suggested-by: Paul Mackerras <paulus@samba.org> Cc: Alexander Graf <agraf@suse.de> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-14Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Pull more powerpc updates from Ben Herrenschmidt: "Here are some more powerpc bits for 3.17, essentially fixes. The biggest series, also aimed at -stable, is from Aneesh and is the result of weeks and weeks of debugging to find out why the heck or THP implementation was occasionally triggering multi-hit errors in our level 1 TLB. It ended up being a combination of issues including subtleties as to how we should invalidate those special 'MPSS' pages we use to allow the use of 16M pages inside 4K/64K "base page size" segments (you really have to love our MMU !) Another interesting one in the "OMG" category is the series from Michael adding memory barriers to spin_is_locked(). That's also the result of many days of debugging to figure out why the semaphore code would occasionally crash in ways that made no sense. It ended up being some creative lock stacking that was defeated by the fact that our locks allow a load inside the locked section to be re-ordered with the load of the lock value itself (I'm still of two mind about whether to kill that once and for all by putting a heavier barrier back into our lock implementation...). The fixes come with a long explanation in the cset comments, feel free to read it if you feel like having a headache today" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits) powerpc/thp: Add tracepoints to track hugepage invalidate powerpc/mm: Use read barrier when creating real_pte powerpc/thp: Use ACCESS_ONCE when loading pmdp powerpc/thp: Invalidate with vpn in loop powerpc/thp: Handle combo pages in invalidate powerpc/thp: Invalidate old 64K based hash page mapping before insert of 4k pte powerpc/thp: Don't recompute vsid and ssize in loop on invalidate powerpc/thp: Add write barrier after updating the valid bit powerpc: reorder per-cpu NUMA information's initialization powerpc/perf/hv-24x7: Use kmem_cache_free powerpc/pseries/hvcserver: Fix endian issue in hvcs_get_partner_info powerpc: Hard disable interrupts in xmon powerpc: remove duplicate definition of TEXASR_FS powerpc/pseries: Avoid deadlock on removing ddw powerpc/pseries: Failure on removing device node powerpc/boot: Use correct zlib types for comparison powerpc/powernv: Interface to register/unregister opal dump region printk: Add function to return log buffer address and size powerpc: Add POWER8 features to CPU_FTRS_POSSIBLE/ALWAYS powerpc/ppc476: Disable BTAC ...
2014-08-14Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linuxLinus Torvalds
Pull device tree updates from Grant Likely: "The branch contains the following device tree changes the v3.17 merge window: Group changes to the device tree. In preparation for adding device tree overlay support, OF_DYNAMIC is reworked so that a set of device tree changes can be prepared and applied to the tree all at once. OF_RECONFIG notifiers see the most significant change here so that users always get a consistent view of the tree. Notifiers generation is moved from before a change to after it, and notifiers for a group of changes are emitted after the entire block of changes have been applied Automatic console selection from DT. Console drivers can now use of_console_check() to see if the device node is specified as a console device. If so then it gets added as a preferred console. UART devices get this support automatically when uart_add_one_port() is called. DT unit tests no longer depend on pre-loaded data in the device tree. Data is loaded dynamically at the start of unit tests, and then unloaded again when the tests have completed. Also contains a few bugfixes for reserved regions and early memory setup" * tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux: (21 commits) of: Fixing OF Selftest build error drivers: of: add automated assignment of reserved regions to client devices of: Use proper types for checking memory overflow of: typo fix in __of_prop_dup() Adding selftest testdata dynamically into live tree of: Add todo tasklist for Devicetree of: Transactional DT support. of: Reorder device tree changes and notifiers of: Move dynamic node fixups out of powerpc and into common code of: Make sure attached nodes don't carry along extra children of: Make devicetree sysfs update functions consistent. of: Create unlocked versions of node and property add/remove functions OF: Utility helper functions for dynamic nodes of: Move CONFIG_OF_DYNAMIC code into a separate file of: rename of_aliases_mutex to just of_mutex of/platform: Fix of_platform_device_destroy iteration of devices of: Migrate of_find_node_by_name() users to for_each_node_by_name() tty: Update hypervisor tty drivers to use core stdout parsing code. arm/versatile: Add the uart as the stdout device. of: Enable console on serial ports specified by /chosen/stdout-path ...
2014-08-13powerpc/thp: Add tracepoints to track hugepage invalidateAneesh Kumar K.V
Add tracepoint to track hugepage invalidate. This help us in debugging difficult to track bugs. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-13powerpc/mm: Use read barrier when creating real_pteAneesh Kumar K.V
On ppc64 we support 4K hash pte with 64K page size. That requires us to track the hash pte slot information on a per 4k basis. We do that by storing the slot details in the second half of pte page. The pte bit _PAGE_COMBO is used to indicate whether the second half need to be looked while building real_pte. We need to use read memory barrier while doing that so that load of hidx is not reordered w.r.t _PAGE_COMBO check. On the store side we already do a lwsync in __hash_page_4K CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-13powerpc/thp: Use ACCESS_ONCE when loading pmdpAneesh Kumar K.V
We would get wrong results in compiler recomputed old_pmd. Avoid that by using ACCESS_ONCE CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-13powerpc/thp: Invalidate with vpn in loopAneesh Kumar K.V
As per ISA, for 4k base page size we compare 14..65 bits of VA specified with the entry_VA in tlb. That implies we need to make sure we do a tlbie with all the possible 4k va we used to access the 16MB hugepage. With 64k base page size we compare 14..57 bits of VA. Hence we cannot ignore the lower 24 bits of va while tlbie .We also cannot tlb invalidate a 16MB entry with just one tlbie instruction because we don't track which va was used to instantiate the tlb entry. CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-13powerpc/thp: Handle combo pages in invalidateAneesh Kumar K.V
If we changed base page size of the segment, either via sub_page_protect or via remap_4k_pfn, we do a demote_segment which doesn't flush the hash table entries. We do a lazy hash page table flush for all mapped pages in the demoted segment. This happens when we handle hash page fault for these pages. We use _PAGE_COMBO bit along with _PAGE_HASHPTE to indicate whether a pte is backed by 4K hash pte. If we find _PAGE_COMBO not set on the pte, that implies that we could possibly have older 64K hash pte entries in the hash page table and we need to invalidate those entries. Use _PAGE_COMBO to determine the page size with which we should invalidate the hash table entries on unmap. CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-13powerpc/thp: Invalidate old 64K based hash page mapping before insert of 4k pteAneesh Kumar K.V
If we changed base page size of the segment, either via sub_page_protect or via remap_4k_pfn, we do a demote_segment which doesn't flush the hash table entries. We do a lazy hash page table flush for all mapped pages in the demoted segment. This happens when we handle hash page fault for these pages. We use _PAGE_COMBO bit along with _PAGE_HASHPTE to indicate whether a pte is backed by 4K hash pte. If we find _PAGE_COMBO not set on the pte, that implies that we could possibly have older 64K hash pte entries in the hash page table and we need to invalidate those entries. Handle this correctly for 16M pages CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-13powerpc/thp: Don't recompute vsid and ssize in loop on invalidateAneesh Kumar K.V
The segment identifier and segment size will remain the same in the loop, So we can compute it outside. We also change the hugepage_invalidate interface so that we can use it the later patch CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-13powerpc/thp: Add write barrier after updating the valid bitAneesh Kumar K.V
With hugepages, we store the hpte valid information in the pte page whose address is stored in the second half of the PMD. Use a write barrier to make sure clearing pmd busy bit and updating hpte valid info are ordered properly. CC: <stable@vger.kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-13powerpc: reorder per-cpu NUMA information's initializationNishanth Aravamudan
There is an issue currently where NUMA information is used on powerpc (and possibly ia64) before it has been read from the device-tree, which leads to large slab consumption with CONFIG_SLUB and memoryless nodes. NUMA powerpc non-boot CPU's cpu_to_node/cpu_to_mem is only accurate after start_secondary(), similar to ia64, which is invoked via smp_init(). Commit 6ee0578b4daae ("workqueue: mark init_workqueues() as early_initcall()") made init_workqueues() be invoked via do_pre_smp_initcalls(), which is obviously before the secondary processors are online. Additionally, the following commits changed init_workqueues() to use cpu_to_node to determine the node to use for kthread_create_on_node: bce903809ab3f ("workqueue: add wq_numa_tbl_len and wq_numa_possible_cpumask[]") f3f90ad469342 ("workqueue: determine NUMA node of workers accourding to the allowed cpumask") Therefore, when init_workqueues() runs, it sees all CPUs as being on Node 0. On LPARs or KVM guests where Node 0 is memoryless, this leads to a high number of slab deactivations (http://www.spinics.net/lists/linux-mm/msg67489.html). Fix this by initializing the powerpc-specific CPU<->node/local memory node mapping as early as possible, which on powerpc is do_init_bootmem(). Currently that function initializes the mapping for the boot CPU, but we extend it to setup the mapping for all possible CPUs. Then, in smp_prepare_cpus(), we can correspondingly set the per-cpu values for all possible CPUs. That ensures that before the early_initcalls run (and really as early as possible), the per-cpu NUMA mapping is accurate. While testing memoryless nodes on PowerKVM guests with a fix to the workqueue logic to use cpu_to_mem() instead of cpu_to_node(), with a guest topology of: available: 2 nodes (0-1) node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 node 0 size: 0 MB node 0 free: 0 MB node 1 cpus: 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 node 1 size: 16336 MB node 1 free: 15329 MB node distances: node 0 1 0: 10 40 1: 40 10 the slab consumption decreases from Slab: 932416 kB SUnreclaim: 902336 kB to Slab: 395264 kB SUnreclaim: 359424 kB And we a corresponding increase in the slab efficiency from slab mem objs slabs used active active ------------------------------------------------------------ kmalloc-16384 337 MB 11.28% 100.00% task_struct 288 MB 9.93% 100.00% to slab mem objs slabs used active active ------------------------------------------------------------ kmalloc-16384 37 MB 100.00% 100.00% task_struct 31 MB 100.00% 100.00% Powerpc didn't support memoryless nodes until recently (64bb80d87f01 "powerpc/numa: Enable CONFIG_HAVE_MEMORYLESS_NODES" and 8c272261194d "powerpc/numa: Enable USE_PERCPU_NUMA_NODE_ID"). Those commits also helped improve memory consumption with these kind of environments. Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>