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| * | s390/uaccess: fix __put_get_user_asm defineHeiko Carstens2016-06-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The __put_get_user_asm defines an inline assmembly which makes use of the asm register construct. The parameters passed to that define may also contain function calls. It is a gcc restriction that between register asm statements and the use of any such annotated variables function calls may clobber the register / variable contents. Or in other words: gcc would generate broken code. This can be achieved e.g. with the following code: get_user(x, func() ? a : b); where the call of func would clobber register zero which is used by the __put_get_user_asm define. To avoid this add two static inline functions which don't have these side effects. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/perf: remove perf_release/reserver_sampling functionsHeiko Carstens2016-06-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that the oprofile sampling code is gone there is only one user of the sampling facility left. Therefore the reserve and release functions can be removed. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390: remove math emulation codeHeiko Carstens2016-06-15
| | | | | | | | | | | | | | | | | | | | | | | | The last in-kernel user is gone so we can finally remove this code. Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/vx: add support functions for in-kernel FPU useHendrik Brueckner2016-06-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce the kernel_fpu_begin() and kernel_fpu_end() function to enclose any in-kernel use of FPU instructions and registers. In enclosed sections, you can perform floating-point or vector (SIMD) computations. The functions take care of saving and restoring FPU register contents and controls. For usage details, see the guidelines in arch/s390/include/asm/fpu/api.h Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/mm: fix compile for PAGE_DEFAULT_KEY != 0Heiko Carstens2016-06-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The usual problem for code that is ifdef'ed out is that it doesn't compile after a while. That's also the case for the storage key initialisation code, if it would be used (set PAGE_DEFAULT_KEY to something not zero): ./arch/s390/include/asm/page.h: In function 'storage_key_init_range': ./arch/s390/include/asm/page.h:36:2: error: implicit declaration of function '__storage_key_init_range' Since the code itself has been useful for debugging purposes several times, remove the ifdefs and make sure the code gets compiler coverage. The cost for this is eight bytes. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/topology: add drawer scheduling domain levelHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The z13 machine added a fourth level to the cpu topology information. The new top level is called drawer. A drawer contains two books, which used to be the top level. Adding this additional scheduling domain did show performance improvements for some workloads of up to 8%, while there don't seem to be any workloads impacted in a negative way. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/ipl: rename diagnose enumsHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename DIAG308_IPL and DIAG308_DUMP to DIAG308_LOAD_CLEAR and DIAG308_LOAD_NORMAL_DUMP to better reflect the associated IPL functions. Suggested-by: Cornelia Huck <cornelia.huck@de.ibm.com> Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390: avoid extable collisionsHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have some inline assemblies where the extable entry points to a label at the end of an inline assembly which is not followed by an instruction. On the other hand we have also inline assemblies where the extable entry points to the first instruction of an inline assembly. If a first type inline asm (extable point to empty label at the end) would be directly followed by a second type inline asm (extable points to first instruction) then we would have two different extable entries that point to the same instruction but would have a different target address. This can lead to quite random behaviour, depending on sorting order. I verified that we currently do not have such collisions within the kernel. However to avoid such subtle bugs add a couple of nop instructions to those inline assemblies which contain an extable that points to an empty label. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/uaccess: use __builtin_expect for get_user/put_userHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We always expect that get_user and put_user return with zero. Give the compiler a hint so it can slightly optimize the code and avoid branches. This is the same what x86 got with commit a76cf66e948a ("x86/uaccess: Tell the compiler that uaccess is unlikely to fault"). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390: use SPARSE_IRQSebastian Ott2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use dynamically allocated irq descriptors on s390 which allows us to get rid of the s390 specific config option PCI_NR_MSI and exploit more MSI interrupts. Also the size of the kernel image is reduced by 131K (using performance_defconfig). Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390: use __section macro everywhereHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | Small cleanup patch to use the shorter __section macro everywhere. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390: add proper __ro_after_init supportHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On s390 __ro_after_init is currently mapped to __read_mostly which means that data marked as __ro_after_init will not be protected. Reason for this is that the common code __ro_after_init implementation is x86 centric: the ro_after_init data section was added to rodata, since x86 enables write protection to kernel text and rodata very late. On s390 we have write protection for these sections enabled with the initial page tables. So adding the ro_after_init data section to rodata does not work on s390. In order to make __ro_after_init work properly on s390 move the ro_after_init data, right behind rodata. Unlike the rodata section it will be marked read-only later after all init calls happened. This s390 specific implementation adds new __start_ro_after_init and __end_ro_after_init labels. Everything in between will be marked read-only after the init calls happened. In addition to the __ro_after_init data move also the exception table there, since from a practical point of view it fits the __ro_after_init requirements. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/mm: simplify the TLB flushing codeMartin Schwidefsky2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/time: remove ETR supportMartin Schwidefsky2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | The External-Time-Reference (ETR) clock synchronization interface has been superseded by Server-Time-Protocol (STP). Remove the outdated ETR interface. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/time: add leap seconds to initial system timeMartin Schwidefsky2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The PTFF instruction can be used to retrieve information about UTC including the current number of leap seconds. Use this value to convert the coordinated server time value of the TOD clock to a proper UTC timestamp to initialize the system time. Without this correction the system time will be off by the number of leap seonds until it has been corrected via NTP. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/time: LPAR offset handlingMartin Schwidefsky2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is possible to specify a user offset for the TOD clock, e.g. +2 hours. The TOD clock will carry this offset even if the clock is synchronized with STP. This makes the time stamps acquired with get_sync_clock() useless as another LPAR migth use a different TOD offset. Use the PTFF instrution to get the TOD epoch difference and subtract it from the TOD clock value to get a physical timestamp. As the epoch difference contains the sync check delta as well the LPAR offset value to the physical clock needs to be refreshed after each clock synchronization. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/time: move PTFF definitionsMartin Schwidefsky2016-06-13
| | | | | | | | | | | | | | | | | | | | | The PTFF instruction is not a function of ETR, rename and move the PTFF definitions from etr.h to timex.h. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/time: STP sync clock correctionMartin Schwidefsky2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | The sync clock operation of the channel subsystem call for STP delivers the TOD clock difference as a result. Use this TOD clock difference instead of the difference between the TOD timestamps before and after the sync clock operation. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/mm: align swapper_pg_dir to 16kHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The segment/region table that is part of the kernel image must be properly aligned to 16k in order to make the crdte inline assembly work. Otherwise it will calculate a wrong segment/region table start address and access incorrect memory locations if the swapper_pg_dir is not aligned to 16k. Therefore define BSS_FIRST_SECTIONS in order to put the swapper_pg_dir at the beginning of the bss section and also align the bss section to 16k just like other architectures did. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390: use canonical include guard styleDaniel van Gerpen2016-06-13
| | | | | | | | | | | | | | | | | | Signed-off-by: Daniel van Gerpen <daniel@vangerpen.de> Acked-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/cpuinfo: show dynamic and static cpu mhzHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Show the dynamic and static cpu mhz of each cpu. Since these values are per cpu this requires a fundamental extension of the format of /proc/cpuinfo. Historically we had only a single line per cpu and a summary at the top of the file. This format is hardly extendible if we want to add more per cpu information. Therefore this patch adds per cpu blocks at the end of /proc/cpuinfo: cpu : 0 cpu Mhz dynamic : 5504 cpu Mhz static : 5504 cpu : 1 cpu Mhz dynamic : 5504 cpu Mhz static : 5504 cpu : 2 cpu Mhz dynamic : 5504 cpu Mhz static : 5504 cpu : 3 cpu Mhz dynamic : 5504 cpu Mhz static : 5504 Right now each block contains only the dynamic and static cpu mhz, but it can be easily extended like on every other architecture. This extension is supposed to be compatible with the old format. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Sascha Silbe <silbe@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390: add explicit <linux/stringify.h> for jump labelJason Baron2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | Ensure that we always have __stringify(). Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/pgtable: add mapping statisticsHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add statistics that show how memory is mapped within the kernel identity mapping. This is more or less the same like git commit ce0c0e50f94e ("x86, generic: CPA add statistics about state of direct mapping v4") for x86. I also intentionally copied the lower case "k" within DirectMap4k vs the upper case "M" and "G" within the two other lines. Let's have consistent inconsistencies across architectures. The output of /proc/meminfo now contains these additional lines: DirectMap4k: 2048 kB DirectMap1M: 3991552 kB DirectMap2G: 4194304 kB The implementation on s390 is lockless unlike the x86 version, since I assume changes to the kernel mapping are a very rare event. Therefore it really doesn't matter if these statistics could potentially be inconsistent if read while kernel pages tables are being changed. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/pageattr: allow kernel page table splittingHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | set_memory_ro() and set_memory_rw() currently only work on 4k mappings, which is good enough for module code aka the vmalloc area. However we stumbled already twice into the need to make this also work on larger mappings: - the ro after init patch set - the crash kernel resize code Therefore this patch implements automatic kernel page table splitting if e.g. set_memory_ro() would be called on parts of a 2G mapping. This works quite the same as the x86 code, but is much simpler. In order to make this work and to be architecturally compliant we now always use the csp, cspg or crdte instructions to replace valid page table entries. This means that set_memory_ro() and set_memory_rw() will be much more expensive than before. In order to avoid huge latencies the code contains a couple of cond_resched() calls. The current code only splits page tables, but does not merge them if it would be possible. The reason for this is that currently there is no real life scenarion where this would really happen. All current use cases that I know of only change access rights once during the life time. If that should change we can still implement kernel page table merging at a later time. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/pgtable: make pmd and pud helper functions availableHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make pmd_wrprotect() and pmd_mkwrite() available independently from CONFIG_TRANSPARENT_HUGEPAGE and CONFIG_HUGETLB_PAGE so these can be used on the kernel mapping. Also introduce a couple of pud helper functions, namely pud_pfn(), pud_wrprotect(), pud_mkwrite(), pud_mkdirty() and pud_mkclean() which only work on the kernel mapping. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/pgtable: get rid of _REGION3_ENTRY_ROHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | _REGION3_ENTRY_RO is a duplicate of _REGION_ENTRY_PROTECT. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/vmem: introduce and use SEGMENT_KERNEL and REGION3_KERNELHeiko Carstens2016-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of open-coded SEGMENT_KERNEL and REGION3_KERNEL assignments use defines. Also to make e.g. pmd_wrprotect() work on the kernel mapping a couple more flags must be set. Therefore add the missing flags also. In order to make everything symmetrical this patch also adds software dirty, young, read and write bits for region 3 table entries. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/pgtable: introduce and use generic csp inline asmHeiko Carstens2016-06-13
| |/ | | | | | | | | | | | | | | | | | | We have already two inline assemblies which make use of the csp instruction. Since I need a third instance let's introduce a generic inline assmebly which can be used by everyone. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | Merge branch 'locking-core-for-linus' of ↵Linus Torvalds2016-07-25
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "The locking tree was busier in this cycle than the usual pattern - a couple of major projects happened to coincide. The main changes are: - implement the atomic_fetch_{add,sub,and,or,xor}() API natively across all SMP architectures (Peter Zijlstra) - add atomic_fetch_{inc/dec}() as well, using the generic primitives (Davidlohr Bueso) - optimize various aspects of rwsems (Jason Low, Davidlohr Bueso, Waiman Long) - optimize smp_cond_load_acquire() on arm64 and implement LSE based atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() on arm64 (Will Deacon) - introduce smp_acquire__after_ctrl_dep() and fix various barrier mis-uses and bugs (Peter Zijlstra) - after discovering ancient spin_unlock_wait() barrier bugs in its implementation and usage, strengthen its semantics and update/fix usage sites (Peter Zijlstra) - optimize mutex_trylock() fastpath (Peter Zijlstra) - ... misc fixes and cleanups" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits) locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire() locking/static_keys: Fix non static symbol Sparse warning locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec() locking/atomic, arch/tile: Fix tilepro build locking/atomic, arch/m68k: Remove comment locking/atomic, arch/arc: Fix build locking/Documentation: Clarify limited control-dependency scope locking/atomic, arch/rwsem: Employ atomic_long_fetch_add() locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire() locking/atomic, arch/mips: Convert to _relaxed atomics locking/atomic, arch/alpha: Convert to _relaxed atomics locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions locking/atomic: Remove linux/atomic.h:atomic_fetch_or() locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() locking/atomic: Fix atomic64_relaxed() bits locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}() locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() ...
| * | locking/atomic: Remove linux/atomic.h:atomic_fetch_or()Peter Zijlstra2016-06-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since all architectures have this implemented now natively, remove this dead code. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/atomic, arch/s390: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()Peter Zijlstra2016-06-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement FETCH-OP atomic primitives, these are very similar to the existing OP-RETURN primitives we already have, except they return the value of the atomic variable _before_ modification. This is especially useful for irreversible operations -- such as bitops (because it becomes impossible to reconstruct the state prior to modification). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-s390@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/spinlock, arch: Update and fix spin_unlock_wait() implementationsPeter Zijlstra2016-06-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates/fixes all spin_unlock_wait() implementations. The update is in semantics; where it previously was only a control dependency, we now upgrade to a full load-acquire to match the store-release from the spin_unlock() we waited on. This ensures that when spin_unlock_wait() returns, we're guaranteed to observe the full critical section we waited on. This fixes a number of spin_unlock_wait() users that (not unreasonably) rely on this. I also fixed a number of ticket lock versions to only wait on the current lock holder, instead of for a full unlock, as this is sufficient. Furthermore; again for ticket locks; I added an smp_rmb() in between the initial ticket load and the spin loop testing the current value because I could not convince myself the address dependency is sufficient, esp. if the loads are of different sizes. I'm more than happy to remove this smp_rmb() again if people are certain the address dependency does indeed work as expected. Note: PPC32 will be fixed independently Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: chris@zankel.net Cc: cmetcalf@mellanox.com Cc: davem@davemloft.net Cc: dhowells@redhat.com Cc: james.hogan@imgtec.com Cc: jejb@parisc-linux.org Cc: linux@armlinux.org.uk Cc: mpe@ellerman.id.au Cc: ralf@linux-mips.org Cc: realmz6@gmail.com Cc: rkuo@codeaurora.org Cc: rth@twiddle.net Cc: schwidefsky@de.ibm.com Cc: tony.luck@intel.com Cc: vgupta@synopsys.com Cc: ysato@users.sourceforge.jp Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | locking/rwsem: Remove rwsem_atomic_add() and rwsem_atomic_update()Jason Low2016-06-08
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The rwsem-xadd count has been converted to an atomic variable and the rwsem code now directly uses atomic_long_add() and atomic_long_add_return(), so we can remove the arch implementations of rwsem_atomic_add() and rwsem_atomic_update(). Signed-off-by: Jason Low <jason.low2@hpe.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Lameter <cl@linux.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Jason Low <jason.low2@hp.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Terry Rudd <terry.rudd@hpe.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Waiman Long <Waiman.Long@hpe.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | s390: fix test_fp_ctl inline assembly contraintsMartin Schwidefsky2016-06-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The test_fp_ctl function is used to test if a given value is a valid floating-point control. The inline assembly in test_fp_ctl uses an incorrect constraint for the 'orig_fpc' variable. If the compiler chooses the same register for 'fpc' and 'orig_fpc' the test_fp_ctl() function always returns true. This allows user space to trigger kernel oopses with invalid floating-point control values on the signal stack. This problem has been introduced with git commit 4725c86055f5bbdcdf "s390: fix save and restore of the floating-point-control register" Cc: stable@vger.kernel.org # v3.13+ Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | KVM: s390: Add stats for PEI eventsAlexander Yarygin2016-06-10
|/ | | | | | | | | Add partial execution intercepted events in kvm_stats_debugfs. Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* Merge branch 'akpm' (patches from Andrew)Linus Torvalds2016-05-19
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge updates from Andrew Morton: - fsnotify fix - poll() timeout fix - a few scripts/ tweaks - debugobjects updates - the (small) ocfs2 queue - Minor fixes to kernel/padata.c - Maybe half of the MM queue * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (117 commits) mm, page_alloc: restore the original nodemask if the fast path allocation failed mm, page_alloc: uninline the bad page part of check_new_page() mm, page_alloc: don't duplicate code in free_pcp_prepare mm, page_alloc: defer debugging checks of pages allocated from the PCP mm, page_alloc: defer debugging checks of freed pages until a PCP drain cpuset: use static key better and convert to new API mm, page_alloc: inline pageblock lookup in page free fast paths mm, page_alloc: remove unnecessary variable from free_pcppages_bulk mm, page_alloc: pull out side effects from free_pages_check mm, page_alloc: un-inline the bad part of free_pages_check mm, page_alloc: check multiple page fields with a single branch mm, page_alloc: remove field from alloc_context mm, page_alloc: avoid looking up the first zone in a zonelist twice mm, page_alloc: shortcut watermark checks for order-0 pages mm, page_alloc: reduce cost of fair zone allocation policy retry mm, page_alloc: shorten the page allocator fast path mm, page_alloc: check once if a zone has isolated pageblocks mm, page_alloc: move __GFP_HARDWALL modifications out of the fastpath mm, page_alloc: simplify last cpupid reset mm, page_alloc: remove unnecessary initialisation from __alloc_pages_nodemask() ...
| * arch: fix has_transparent_hugepage()Hugh Dickins2016-05-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I've just discovered that the useful-sounding has_transparent_hugepage() is actually an architecture-dependent minefield: on some arches it only builds if CONFIG_TRANSPARENT_HUGEPAGE=y, on others it's also there when not, but on some of those (arm and arm64) it then gives the wrong answer; and on mips alone it's marked __init, which would crash if called later (but so far it has not been called later). Straighten this out: make it available to all configs, with a sensible default in asm-generic/pgtable.h, removing its definitions from those arches (arc, arm, arm64, sparc, tile) which are served by the default, adding #define has_transparent_hugepage has_transparent_hugepage to those (mips, powerpc, s390, x86) which need to override the default at runtime, and removing the __init from mips (but maybe that kind of code should be avoided after init: set a static variable the first time it's called). Signed-off-by: Hugh Dickins <hughd@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andres Lagar-Cavilla <andreslc@google.com> Cc: Yang Shi <yang.shi@linaro.org> Cc: Ning Qu <quning@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc] Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> [arch/s390] Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2016-05-19
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Paolo Bonzini: "Small release overall. x86: - miscellaneous fixes - AVIC support (local APIC virtualization, AMD version) s390: - polling for interrupts after a VCPU goes to halted state is now enabled for s390 - use hardware provided information about facility bits that do not need any hypervisor activity, and other fixes for cpu models and facilities - improve perf output - floating interrupt controller improvements. MIPS: - miscellaneous fixes PPC: - bugfixes only ARM: - 16K page size support - generic firmware probing layer for timer and GIC Christoffer Dall (KVM-ARM maintainer) says: "There are a few changes in this pull request touching things outside KVM, but they should all carry the necessary acks and it made the merge process much easier to do it this way." though actually the irqchip maintainers' acks didn't make it into the patches. Marc Zyngier, who is both irqchip and KVM-ARM maintainer, later acked at http://mid.gmane.org/573351D1.4060303@arm.com ('more formally and for documentation purposes')" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (82 commits) KVM: MTRR: remove MSR 0x2f8 KVM: x86: make hwapic_isr_update and hwapic_irr_update look the same svm: Manage vcpu load/unload when enable AVIC svm: Do not intercept CR8 when enable AVIC svm: Do not expose x2APIC when enable AVIC KVM: x86: Introducing kvm_x86_ops.apicv_post_state_restore svm: Add VMEXIT handlers for AVIC svm: Add interrupt injection via AVIC KVM: x86: Detect and Initialize AVIC support svm: Introduce new AVIC VMCB registers KVM: split kvm_vcpu_wake_up from kvm_vcpu_kick KVM: x86: Introducing kvm_x86_ops VCPU blocking/unblocking hooks KVM: x86: Introducing kvm_x86_ops VM init/destroy hooks KVM: x86: Rename kvm_apic_get_reg to kvm_lapic_get_reg KVM: x86: Misc LAPIC changes to expose helper functions KVM: shrink halt polling even more for invalid wakeups KVM: s390: set halt polling to 80 microseconds KVM: halt_polling: provide a way to qualify wakeups during poll KVM: PPC: Book3S HV: Re-enable XICS fast path for irqfd-generated interrupts kvm: Conditionally register IRQ bypass consumer ...
| * KVM: s390: set halt polling to 80 microsecondsChristian Borntraeger2016-05-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | on s390 we disabled the halt polling with commit 920552b213e3 ("KVM: disable halt_poll_ns as default for s390x"), as floating interrupts would let all CPUs have a successful poll, resulting in much higher CPU usage (on otherwise idle systems). With the improved selection of polls we can now retry halt polling. Performance measurements with different choices like 25,50,80,100,200 microseconds showed that 80 microseconds seems to improve several cases without increasing the CPU costs too much. Higher values would improve the performance even more but increased the cpu time as well. So let's start small and use this value of 80 microseconds on s390 until we have a better understanding of cost/benefit of higher values. Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * KVM: halt_polling: provide a way to qualify wakeups during pollChristian Borntraeger2016-05-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some wakeups should not be considered a sucessful poll. For example on s390 I/O interrupts are usually floating, which means that _ALL_ CPUs would be considered runnable - letting all vCPUs poll all the time for transactional like workload, even if one vCPU would be enough. This can result in huge CPU usage for large guests. This patch lets architectures provide a way to qualify wakeups if they should be considered a good/bad wakeups in regard to polls. For s390 the implementation will fence of halt polling for anything but known good, single vCPU events. The s390 implementation for floating interrupts does a wakeup for one vCPU, but the interrupt will be delivered by whatever CPU checks first for a pending interrupt. We prefer the woken up CPU by marking the poll of this CPU as "good" poll. This code will also mark several other wakeup reasons like IPI or expired timers as "good". This will of course also mark some events as not sucessful. As KVM on z runs always as a 2nd level hypervisor, we prefer to not poll, unless we are really sure, though. This patch successfully limits the CPU usage for cases like uperf 1byte transactional ping pong workload or wakeup heavy workload like OLTP while still providing a proper speedup. This also introduced a new vcpu stat "halt_poll_no_tuning" that marks wakeups that are considered not good for polling. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Radim Krčmář <rkrcmar@redhat.com> (for an earlier version) Cc: David Matlack <dmatlack@google.com> Cc: Wanpeng Li <kernellwp@gmail.com> [Rename config symbol. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * s390/sclp: Add hmfai fieldAlexander Yarygin2016-05-09
| | | | | | | | | | | | | | | | | | | | | | Let's add hypervisor-managed facility-apportionment indications field to SCLP structs. KVM will use it to reduce maintenance cost of Non-Hypervisor-Managed facility bits. Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * KVM: s390: cleanup cpuid handlingDavid Hildenbrand2016-05-09
| | | | | | | | | | | | | | | | | | We only have one cpuid for all VCPUs, so let's directly use the one in the cpu model. Also always store it directly as u64, no need for struct cpuid. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * KVM: s390: enable SRS only if enabled for the guestDavid Hildenbrand2016-05-09
| | | | | | | | | | | | | | | | | | If we don't have SIGP SENSE RUNNING STATUS enabled for the guest, let's not enable interpretation so we can correctly report an invalid order. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| * KVM: s390: add clear I/O irq operation for FLICHalil Pasic2016-04-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce a FLIC operation for clearing I/O interrupts for a subchannel. Rationale: According to the platform specification, pending I/O interruption requests have to be revoked in certain situations. For instance, according to the Principles of Operation (page 17-27), a subchannel put into the installed parameters initialized state is in the same state as after an I/O system reset (just parameters possibly changed). This implies that any I/O interrupts for that subchannel are no longer pending (as I/O system resets clear I/O interrupts). Therefore, we need an interface to clear pending I/O interrupts. Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
| * KVM: s390/perf: provide additional sigp eventsChristian Borntraeger2016-04-20
| | | | | | | | | | | | | | | | | | | | | | perf kvm stat can decode sigp events, let's make the list complete by adding the missing ones. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Acked-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2016-05-18
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: "The s390 patches for the 4.7 merge window have the usual bug fixes and cleanups, and the following new features: - An interface for dasd driver to query if a volume is online to another operating system - A new ioctl for the dasd driver to verify the format for a range of tracks - Following the example of x86 the struct fpu is now allocated with the task_struct - The 'report_error' interface for the PCI bus to send an adapter-error notification from user space to the service element of the machine" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (29 commits) s390/vmem: remove unused function parameter s390/vmem: fix identity mapping s390: add missing include statements s390: add missing declarations s390: make couple of variables and functions static s390/cache: remove superfluous locking s390/cpuinfo: simplify locking and skip offline cpus early s390/3270: hangup the 3270 tty after a disconnect s390/3270: handle reconnect of a tty with a different size s390/3270: avoid endless I/O loop with disconnected 3270 terminals s390/3270: fix garbled output on 3270 tty view s390/3270: fix view reference counting s390/3270: add missing tty_kref_put s390/dumpstack: implement and use return_address() s390/cpum_sf: Remove superfluous SMP function call s390/cpum_cf: Remove superfluous SMP function call s390/Kconfig: make z196 the default processor type s390/sclp: avoid compile warning in sclp_pci_report s390/fpu: allocate 'struct fpu' with the task_struct s390/crypto: cleanup and move the header with the cpacf definitions ...
| * | s390: add missing declarationsHeiko Carstens2016-05-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | arch_dup_task_struct and the per cpu variable mt_cycles are globally visible, but do not have any header file with a declaration. Therefore add it so we have proper type checking in place. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/dumpstack: implement and use return_address()Heiko Carstens2016-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement return_address() and use it instead of __builtin_return_address(n). __builtin_return_address(n) is not guaranteed to work for n > 0, therefore implement a private return_address() function which walks the stack frames and returns the proper return address. This way we get also rid of a compile warning which gcc 6.1 emits and look like all other architectures. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/fpu: allocate 'struct fpu' with the task_structMartin Schwidefsky2016-04-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Analog to git commit 0c8c0f03e3a292e031596484275c14cf39c0ab7a "x86/fpu, sched: Dynamically allocate 'struct fpu'" move the struct fpu to the end of the struct thread_struct, set CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and add the setup_task_size() function to calculate the correct size fo the task struct. For the performance_defconfig this increases the size of struct task_struct from 7424 bytes to 7936 bytes (MACHINE_HAS_VX==1) or 7552 bytes (MACHINE_HAS_VX==0). The dynamic allocation of the struct fpu is removed. The slab cache uses an 8KB block for the task struct in all cases, there is enough room for the struct fpu. For MACHINE_HAS_VX==1 each task now needs 512 bytes less memory. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * | s390/crypto: cleanup and move the header with the cpacf definitionsMartin Schwidefsky2016-04-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The CPACF instructions are going be used in KVM as well, move the defines and the inline functions from arch/s390/crypt/crypt_s390.h to arch/s390/include/asm. Rename the header to cpacf.h and replace the crypt_s390_xxx names with cpacf_xxx. While we are at it, cleanup the header as well. The encoding for the CPACF operations is odd, there is an enum for each of the CPACF instructions with the hardware function code in the lower 8 bits of each entry and a software defined number for the CPACF instruction in the upper 8 bits. Remove the superfluous software number and replace the enums with simple defines. The crypt_s390_func_available() function tests for the presence of a specific CPACF operations. The new name of the function is cpacf_query and it works slightly different than before. It gets passed an opcode of an CPACF instruction and a function code for this instruction. The facility_mask parameter is gone, the opcode is used to find the correct MSA facility bit to check if the CPACF instruction itself is available. If it is the query function of the given instruction is used to test if the requested CPACF operation is present. Acked-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>