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2024-09-03x86: remove PG_uncachedMatthew Wilcox (Oracle)
Convert x86 to use PG_arch_2 instead of PG_uncached and remove PG_uncached. Link: https://lkml.kernel.org/r/20240821193445.2294269-11-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-20LoongArch: Add ARCH_HAS_DEBUG_VM_PGTABLE supportHuacai Chen
Add ARCH_HAS_DEBUG_VM_PGTABLE selection in Kconfig, in order to make corresponding vm debug features usable on LoongArch. Also update the corresponding arch-support.txt document. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-02-15membarrier: riscv: Provide core serializing commandAndrea Parri
RISC-V uses xRET instructions on return from interrupt and to go back to user-space; the xRET instruction is not core serializing. Use FENCE.I for providing core serialization as follows: - by calling sync_core_before_usermode() on return from interrupt (cf. ipi_sync_core()), - via switch_mm() and sync_core_before_usermode() (respectively, for uthread->uthread and kthread->uthread transitions) before returning to user-space. On RISC-V, the serialization in switch_mm() is activated by resetting the icache_stale_mask of the mm at prepare_sync_core_cmd(). Suggested-by: Palmer Dabbelt <palmer@dabbelt.com> Signed-off-by: Andrea Parri <parri.andrea@gmail.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://lore.kernel.org/r/20240131144936.29190-5-parri.andrea@gmail.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-11riscv: Add support for BATCHED_UNMAP_TLB_FLUSHAlexandre Ghiti
Allow to defer the flushing of the TLB when unmapping pages, which allows to reduce the numbers of IPI and the number of sfence.vma. The ubenchmarch used in commit 43b3dfdd0455 ("arm64: support batched/deferred tlb shootdown during page reclamation/migration") that was multithreaded to force the usage of IPI shows good performance improvement on all platforms: * Unmatched: ~34% * TH1520 : ~78% * Qemu : ~81% In addition, perf on qemu reports an important decrease in time spent dealing with IPIs: Before: 68.17% main [kernel.kallsyms] [k] __sbi_rfence_v02_call After : 8.64% main [kernel.kallsyms] [k] __sbi_rfence_v02_call * Benchmark: int stick_this_thread_to_core(int core_id) { int num_cores = sysconf(_SC_NPROCESSORS_ONLN); if (core_id < 0 || core_id >= num_cores) return EINVAL; cpu_set_t cpuset; CPU_ZERO(&cpuset); CPU_SET(core_id, &cpuset); pthread_t current_thread = pthread_self(); return pthread_setaffinity_np(current_thread, sizeof(cpu_set_t), &cpuset); } static void *fn_thread (void *p_data) { int ret; pthread_t thread; stick_this_thread_to_core((int)p_data); while (1) { sleep(1); } return NULL; } int main() { volatile unsigned char *p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); pthread_t threads[4]; int ret; for (int i = 0; i < 4; ++i) { ret = pthread_create(&threads[i], NULL, fn_thread, (void *)i); if (ret) { printf("%s", strerror (ret)); } } memset(p, 0x88, SIZE); for (int k = 0; k < 10000; k++) { /* swap in */ for (int i = 0; i < SIZE; i += 4096) { (void)p[i]; } /* swap out */ madvise(p, SIZE, MADV_PAGEOUT); } for (int i = 0; i < 4; i++) { pthread_cancel(threads[i]); } for (int i = 0; i < 4; i++) { pthread_join(threads[i], NULL); } return 0; } Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Jisheng Zhang <jszhang@kernel.org> Tested-by: Jisheng Zhang <jszhang@kernel.org> # Tested on TH1520 Tested-by: Nam Cao <namcao@linutronix.de> Link: https://lore.kernel.org/r/20240108193640.344929-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-09-11Documentation: Drop IA64 from feature descriptionsArd Biesheuvel
Itanium (IA64) is going away, so drop it from the kernel feature documentation. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-09-08Merge tag 'loongarch-6.6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch updates from Huacai Chen: - Allow usage of LSX/LASX in the kernel, and use them for SIMD-optimized RAID5/RAID6 routines - Add Loongson Binary Translation (LBT) extension support - Add basic KGDB & KDB support - Add building with kcov coverage - Add KFENCE (Kernel Electric-Fence) support - Add KASAN (Kernel Address Sanitizer) support - Some bug fixes and other small changes - Update the default config file * tag 'loongarch-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (25 commits) LoongArch: Update Loongson-3 default config file LoongArch: Add KASAN (Kernel Address Sanitizer) support LoongArch: Simplify the processing of jumping new kernel for KASLR kasan: Add (pmd|pud)_init for LoongArch zero_(pud|p4d)_populate process kasan: Add __HAVE_ARCH_SHADOW_MAP to support arch specific mapping LoongArch: Add KFENCE (Kernel Electric-Fence) support LoongArch: Get partial stack information when providing regs parameter LoongArch: mm: Add page table mapped mode support for virt_to_page() kfence: Defer the assignment of the local variable addr LoongArch: Allow building with kcov coverage LoongArch: Provide kaslr_offset() to get kernel offset LoongArch: Add basic KGDB & KDB support LoongArch: Add Loongson Binary Translation (LBT) extension support raid6: Add LoongArch SIMD recovery implementation raid6: Add LoongArch SIMD syndrome calculation LoongArch: Add SIMD-optimized XOR routines LoongArch: Allow usage of LSX/LASX in the kernel LoongArch: Define symbol 'fault' as a local label in fpu.S LoongArch: Adjust {copy, clear}_user exception handler behavior LoongArch: Use static defined zero page rather than allocated ...
2023-09-06LoongArch: Add KASAN (Kernel Address Sanitizer) supportQing Zhang
1/8 of kernel addresses reserved for shadow memory. But for LoongArch, There are a lot of holes between different segments and valid address space (256T available) is insufficient to map all these segments to kasan shadow memory with the common formula provided by kasan core, saying (addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET So LoongArch has a arch-specific mapping formula, different segments are mapped individually, and only limited space lengths of these specific segments are mapped to shadow. At early boot stage the whole shadow region populated with just one physical page (kasan_early_shadow_page). Later, this page is reused as readonly zero shadow for some memory that kasan currently don't track. After mapping the physical memory, pages for shadow memory are allocated and mapped. Functions like memset()/memcpy()/memmove() do a lot of memory accesses. If bad pointer passed to one of these function it is important to be caught. Compiler's instrumentation cannot do this since these functions are written in assembly. KASan replaces memory functions with manually instrumented variants. Original functions declared as weak symbols so strong definitions in mm/kasan/kasan.c could replace them. Original functions have aliases with '__' prefix in names, so we could call non-instrumented variant if needed. Signed-off-by: Qing Zhang <zhangqing@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-06LoongArch: Allow building with kcov coverageFeiyang Chen
Add ARCH_HAS_KCOV and HAVE_GCC_PLUGINS to the LoongArch Kconfig. And also disable instrumentation of vdso. Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-06LoongArch: Add basic KGDB & KDB supportQing Zhang
KGDB is intended to be used as a source level debugger for the Linux kernel. It is used along with gdb to debug a Linux kernel. GDB can be used to "break in" to the kernel to inspect memory, variables and regs similar to the way an application developer would use GDB to debug an application. KDB is a frontend of KGDB which is similar to GDB. By now, in addition to the generic KGDB features, the LoongArch KGDB implements the following features: - Hardware breakpoints/watchpoints; - Software single-step support for KDB. Signed-off-by: Qing Zhang <zhangqing@loongson.cn> # Framework & CoreFeature Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn> # BreakPoint & SingleStep Signed-off-by: Hui Li <lihui@loongson.cn> # Some Minor Improvements Signed-off-by: Randy Dunlap <rdunlap@infradead.org> # Some Build Error Fixes Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-08-30Merge tag 'docs-6.6' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "Documentation work keeps chugging along; this includes: - Work from Carlos Bilbao to integrate rustdoc output into the generated HTML documentation. This took some work to figure out how to do it without slowing the docs build and without creating people who don't have Rust installed, but Carlos got there - Move the loongarch and mips architecture documentation under Documentation/arch/ - Some more maintainer documentation from Jakub ... plus the usual assortment of updates, translations, and fixes" * tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits) Docu: genericirq.rst: fix irq-example input: docs: pxrc: remove reference to phoenix-sim Documentation: serial-console: Fix literal block marker docs/mm: remove references to hmm_mirror ops and clean typos docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add() Documentation: Fix typos Documentation/ABI: Fix typos scripts: kernel-doc: fix macro handling in enums scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN] Documentation: riscv: Update boot image header since EFI stub is supported Documentation: riscv: Add early boot document Documentation: arm: Add bootargs to the table of added DT parameters docs: kernel-parameters: Refer to the correct bitmap function doc: update params of memhp_default_state= docs: Add book to process/kernel-docs.rst docs: sparse: fix invalid link addresses docs: vfs: clean up after the iterate() removal docs: Add a section on surveys to the researcher guidelines docs: move mips under arch docs: move loongarch under arch ...
2023-08-18Documentation: Fix typosBjorn Helgaas
Fix typos in Documentation. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20230814212822.193684-4-helgaas@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-08-18arm64: support batched/deferred tlb shootdown during page reclamation/migrationBarry Song
On x86, batched and deferred tlb shootdown has lead to 90% performance increase on tlb shootdown. on arm64, HW can do tlb shootdown without software IPI. But sync tlbi is still quite expensive. Even running a simplest program which requires swapout can prove this is true, #include <sys/types.h> #include <unistd.h> #include <sys/mman.h> #include <string.h> int main() { #define SIZE (1 * 1024 * 1024) volatile unsigned char *p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); memset(p, 0x88, SIZE); for (int k = 0; k < 10000; k++) { /* swap in */ for (int i = 0; i < SIZE; i += 4096) { (void)p[i]; } /* swap out */ madvise(p, SIZE, MADV_PAGEOUT); } } Perf result on snapdragon 888 with 8 cores by using zRAM as the swap block device. ~ # perf record taskset -c 4 ./a.out [ perf record: Woken up 10 times to write data ] [ perf record: Captured and wrote 2.297 MB perf.data (60084 samples) ] ~ # perf report # To display the perf.data header info, please use --header/--header-only options. # To display the perf.data header info, please use --header/--header-only options. # # # Total Lost Samples: 0 # # Samples: 60K of event 'cycles' # Event count (approx.): 35706225414 # # Overhead Command Shared Object Symbol # ........ ....... ................. ...... # 21.07% a.out [kernel.kallsyms] [k] _raw_spin_unlock_irq 8.23% a.out [kernel.kallsyms] [k] _raw_spin_unlock_irqrestore 6.67% a.out [kernel.kallsyms] [k] filemap_map_pages 6.16% a.out [kernel.kallsyms] [k] __zram_bvec_write 5.36% a.out [kernel.kallsyms] [k] ptep_clear_flush 3.71% a.out [kernel.kallsyms] [k] _raw_spin_lock 3.49% a.out [kernel.kallsyms] [k] memset64 1.63% a.out [kernel.kallsyms] [k] clear_page 1.42% a.out [kernel.kallsyms] [k] _raw_spin_unlock 1.26% a.out [kernel.kallsyms] [k] mod_zone_state.llvm.8525150236079521930 1.23% a.out [kernel.kallsyms] [k] xas_load 1.15% a.out [kernel.kallsyms] [k] zram_slot_lock ptep_clear_flush() takes 5.36% CPU in the micro-benchmark swapping in/out a page mapped by only one process. If the page is mapped by multiple processes, typically, like more than 100 on a phone, the overhead would be much higher as we have to run tlb flush 100 times for one single page. Plus, tlb flush overhead will increase with the number of CPU cores due to the bad scalability of tlb shootdown in HW, so those ARM64 servers should expect much higher overhead. Further perf annonate shows 95% cpu time of ptep_clear_flush is actually used by the final dsb() to wait for the completion of tlb flush. This provides us a very good chance to leverage the existing batched tlb in kernel. The minimum modification is that we only send async tlbi in the first stage and we send dsb while we have to sync in the second stage. With the above simplest micro benchmark, collapsed time to finish the program decreases around 5%. Typical collapsed time w/o patch: ~ # time taskset -c 4 ./a.out 0.21user 14.34system 0:14.69elapsed w/ patch: ~ # time taskset -c 4 ./a.out 0.22user 13.45system 0:13.80elapsed Also tested with benchmark in the commit on Kunpeng920 arm64 server and observed an improvement around 12.5% with command `time ./swap_bench`. w/o w/ real 0m13.460s 0m11.771s user 0m0.248s 0m0.279s sys 0m12.039s 0m11.458s Originally it's noticed a 16.99% overhead of ptep_clear_flush() which has been eliminated by this patch: [root@localhost yang]# perf record -- ./swap_bench && perf report [...] 16.99% swap_bench [kernel.kallsyms] [k] ptep_clear_flush It is tested on 4,8,128 CPU platforms and shows to be beneficial on large systems but may not have improvement on small systems like on a 4 CPU platform. Also this patch improve the performance of page migration. Using pmbench and tries to migrate the pages of pmbench between node 0 and node 1 for 100 times for 1G memory, this patch decrease the time used around 20% (prev 18.338318910 sec after 13.981866350 sec) and saved the time used by ptep_clear_flush(). Link: https://lkml.kernel.org/r/20230717131004.12662-5-yangyicong@huawei.com Tested-by: Yicong Yang <yangyicong@hisilicon.com> Tested-by: Xin Hao <xhao@linux.alibaba.com> Tested-by: Punit Agrawal <punit.agrawal@bytedance.com> Signed-off-by: Barry Song <v-songbaohua@oppo.com> Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Xin Hao <xhao@linux.alibaba.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Nadav Amit <namit@vmware.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Barry Song <baohua@kernel.org> Cc: Darren Hart <darren@os.amperecomputing.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: lipeifeng <lipeifeng@oppo.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Steven Miao <realmz6@gmail.com> Cc: Will Deacon <will@kernel.org> Cc: Zeng Tao <prime.zeng@hisilicon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-07-14Documentation/features: Refresh support files for 6.5Tiezhu Yang
Run the refresh script [1] to document the recent feature additions. [1] Documentation/features/scripts/features-refresh.sh Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/1689060720-4628-3-git-send-email-yangtiezhu@loongson.cn
2023-07-14Documentation/features: Check ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUTTiezhu Yang
ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT selects ARCH_HAS_ELF_RANDOMIZE, so add ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT as another Kconfig check for ELF-ASLR feature, then the refresh script can be used to handle this case for all archs. Co-developed-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/1689060720-4628-2-git-send-email-yangtiezhu@loongson.cn
2023-06-29LoongArch: Add jump-label implementationYouling Tang
Add support for jump labels based on the ARM64 version. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-06-29LoongArch: Select HAVE_DEBUG_KMEMLEAK to support kmemleakTiezhu Yang
We can see that DEBUG_KMEMLEAK depends on HAVE_DEBUG_KMEMLEAK after commit b69ec42b1b19 ("Kconfig: clean up the long arch list for the DEBUG_KMEMLEAK config option"), just select HAVE_DEBUG_KMEMLEAK to support kmemleak on LoongArch. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-03-27s390: enable ARCH_HAS_MEMBARRIER_SYNC_COREHeiko Carstens
s390 trivially supports the ARCH_HAS_MEMBARRIER_SYNC_CORE requirements since the used lpswe(y) instruction to return from any kernel context to user space performs CPU serialization. This is very similar to arm, arm64 and powerpc. See commit 70216e18e519 ("membarrier: Provide core serializing command, *_SYNC_CORE") for further details. Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-01-30m68k: Add kernel seccomp supportMichael Schmitz
Add secure_computing() call to syscall_trace_enter to actually filter system calls. Add necessary arch Kconfig options, define TIF_SECCOMP trace flag and provide basic seccomp filter support in asm/syscall.h syscall_get_nr currently uses the syscall nr stored in orig_d0 because we change d0 to a default return code before starting a syscall trace. This may be inconsistent with syscall_rollback copying orig_d0 to d0 (which we never check upon return from trace). We use d0 for the return code from syscall_trace_enter in entry.S currently, and could perhaps expand that to store a new syscall number returned by the seccomp filter before executing the syscall. This clearly needs some discussion. seccomp_bpf self test on ARAnyM passes 81 out of 94 tests. Signed-off-by: Michael Schmitz <schmitzmic@gmail.com> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20230112035529.13521-3-schmitzmic@gmail.com Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2022-12-14Merge tag 'riscv-for-linus-6.2-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for the T-Head PMU via the perf subsystem - ftrace support for rv32 - Support for non-volatile memory devices - Various fixes and cleanups * tag 'riscv-for-linus-6.2-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (52 commits) Documentation: RISC-V: patch-acceptance: s/implementor/implementer Documentation: RISC-V: Mention the UEFI Standards Documentation: RISC-V: Allow patches for non-standard behavior Documentation: RISC-V: Fix a typo in patch-acceptance riscv: Fixup compile error with !MMU riscv: Fix P4D_SHIFT definition for 3-level page table mode riscv: Apply a static assert to riscv_isa_ext_id RISC-V: Add some comments about the shadow and overflow stacks RISC-V: Align the shadow stack RISC-V: Ensure Zicbom has a valid block size RISC-V: Introduce riscv_isa_extension_check RISC-V: Improve use of isa2hwcap[] riscv: Don't duplicate _ALTERNATIVE_CFG* macros riscv: alternatives: Drop the underscores from the assembly macro names riscv: alternatives: Don't name unused macro parameters riscv: Don't duplicate __ALTERNATIVE_CFG in __ALTERNATIVE_CFG_2 riscv: mm: call best_map_size many times during linear-mapping riscv: Move cast inside kernel_mapping_[pv]a_to_[vp]a riscv: Fix crash during early errata patching riscv: boot: add zstd support ...
2022-12-05Documentation/features: Use loongarch instead of loongTiezhu Yang
The official arch name is LoongArch [1], we should use small letter loongarch instead of loong in Documentation/features, just use the features-refresh.sh to refresh all the related files. [1] https://www.kernel.org/doc/html/latest/loongarch/index.html Fixes: 5860800e8696 ("Documentation/features: Update the arch support status files") Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Link: https://lore.kernel.org/r/1670156327-9631-3-git-send-email-yangtiezhu@loongson.cn Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-12-05Documentation/features-refresh.sh: Only sed the beginning "arch" of ARCH_DIRTiezhu Yang
It should only sed the beginning "arch" of ARCH_DIR in features-refresh.sh, otherwise loongarch is recognized as loong, that is not what we want. Fixes: be99f610a110 ("Documentation/features: Add script that refreshes the arch support status files in place") Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Link: https://lore.kernel.org/r/1670156327-9631-2-git-send-email-yangtiezhu@loongson.cn Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-12-03Documentation/features: Update feature lists for 6.1Wei Li
Run the refresh script to document the recent feature additions on loong, um and csky as of v6.1-rc7. Signed-off-by: Wei Li <liwei391@huawei.com> Link: https://lore.kernel.org/r/20221203093750.4145802-1-liwei391@huawei.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-10-28riscv: Enable HAVE_ARCH_HUGE_VMAP for 64BITLiu Shixin
This sets the HAVE_ARCH_HUGE_VMAP option, and defines the required page table functions. With this feature, ioremap area will be mapped with huge page granularity according to its actual size. This feature can be disabled by kernel parameter "nohugeiomap". Signed-off-by: Liu Shixin <liushixin2@huawei.com> Reviewed-by: Björn Töpel <bjorn@kernel.org> Tested-by: Björn Töpel <bjorn@kernel.org> Link: https://lore.kernel.org/r/20221012120038.1034354-2-liushixin2@huawei.com [Palmer: minor formatting] Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-08-04Merge tag 'xtensa-20220804' of https://github.com/jcmvbkbc/linux-xtensaLinus Torvalds
Pull xtensa updates from Max Filippov: - support KCOV - enable ARCH_HAS_GCOV_PROFILE_ALL - minor ISS network driver cleanups * tag 'xtensa-20220804' of https://github.com/jcmvbkbc/linux-xtensa: xtensa: enable ARCH_HAS_GCOV_PROFILE_ALL xtensa: enable KCOV support xtensa: iss: fix handling error cases in iss_net_configure() xtensa: iss/network: provide release() callback xtensa: iss/network: drop 'devices' list
2022-08-02Merge tag 'rcu.2022.07.26a' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu Pull RCU updates from Paul McKenney: - Documentation updates - Miscellaneous fixes - Callback-offload updates, perhaps most notably a new RCU_NOCB_CPU_DEFAULT_ALL Kconfig option that causes all CPUs to be offloaded at boot time, regardless of kernel boot parameters. This is useful to battery-powered systems such as ChromeOS and Android. In addition, a new RCU_NOCB_CPU_CB_BOOST kernel boot parameter prevents offloaded callbacks from interfering with real-time workloads and with energy-efficiency mechanisms - Polled grace-period updates, perhaps most notably making these APIs account for both normal and expedited grace periods - Tasks RCU updates, perhaps most notably reducing the CPU overhead of RCU tasks trace grace periods by more than a factor of two on a system with 15,000 tasks. The reduction is expected to increase with the number of tasks, so it seems reasonable to hypothesize that a system with 150,000 tasks might see a 20-fold reduction in CPU overhead - Torture-test updates - Updates that merge RCU's dyntick-idle tracking into context tracking, thus reducing the overhead of transitioning to kernel mode from either idle or nohz_full userspace execution for kernels that track context independently of RCU. This is expected to be helpful primarily for kernels built with CONFIG_NO_HZ_FULL=y * tag 'rcu.2022.07.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (98 commits) rcu: Add irqs-disabled indicator to expedited RCU CPU stall warnings rcu: Diagnose extended sync_rcu_do_polled_gp() loops rcu: Put panic_on_rcu_stall() after expedited RCU CPU stall warnings rcutorture: Test polled expedited grace-period primitives rcu: Add polled expedited grace-period primitives rcutorture: Verify that polled GP API sees synchronous grace periods rcu: Make Tiny RCU grace periods visible to polled APIs rcu: Make polled grace-period API account for expedited grace periods rcu: Switch polled grace-period APIs to ->gp_seq_polled rcu/nocb: Avoid polling when my_rdp->nocb_head_rdp list is empty rcu/nocb: Add option to opt rcuo kthreads out of RT priority rcu: Add nocb_cb_kthread check to rcu_is_callbacks_kthread() rcu/nocb: Add an option to offload all CPUs on boot rcu/nocb: Fix NOCB kthreads spawn failure with rcu_nocb_rdp_deoffload() direct call rcu/nocb: Invert rcu_state.barrier_mutex VS hotplug lock locking order rcu/nocb: Add/del rdp to iterate from rcuog itself rcu/tree: Add comment to describe GP-done condition in fqs loop rcu: Initialize first_gp_fqs at declaration in rcu_gp_fqs() rcu/kvfree: Remove useless monitor_todo flag rcu: Cleanup RCU urgency state for offline CPU ...
2022-07-14xtensa: enable ARCH_HAS_GCOV_PROFILE_ALLMax Filippov
Select ARCH_HAS_GCOV_PROFILE_ALL and set GCOV_PROFILE = n inside arch/xtensa/boot/lib. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-07-14xtensa: enable KCOV supportMax Filippov
Select ARCH_HAS_KCOV and set KCOV_INSTRUMENT = n inside arch/xtensa/boot/lib. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-06-29context_tracking: Split user tracking KconfigFrederic Weisbecker
Context tracking is going to be used not only to track user transitions but also idle/IRQs/NMIs. The user tracking part will then become a separate feature. Prepare Kconfig for that. [ frederic: Apply Max Filippov feedback. ] Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com> Cc: Uladzislau Rezki <uladzislau.rezki@sony.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Nicolas Saenz Julienne <nsaenz@kernel.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com> Cc: Yu Liao <liaoyu15@huawei.com> Cc: Phil Auld <pauld@redhat.com> Cc: Paul Gortmaker<paul.gortmaker@windriver.com> Cc: Alex Belits <abelits@marvell.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
2022-06-27arm64: Add HAVE_IOREMAP_PROT supportKefeng Wang
With ioremap_prot() definition from generic ioremap, also move pte_pgprot() from hugetlbpage.c into pgtable.h, then arm64 could have HAVE_IOREMAP_PROT, which will enable generic_access_phys() code, it is useful for debug, eg, gdb. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Link: https://lore.kernel.org/r/20220607125027.44946-7-wangkefeng.wang@huawei.com Signed-off-by: Will Deacon <will@kernel.org>
2022-06-09Documentation/features: Update the arch support status filesZheng Zengkai
The arch support status files don't match reality as of v5.19-rc1, use the features-refresh.sh to refresh all the arch-support.txt files in place. The main effect is to add entries for the new loong architecture. Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Link: https://lore.kernel.org/r/20220609025656.143460-1-zhengzengkai@huawei.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-05-26Merge tag 'asm-generic-5.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "The asm-generic tree contains three separate changes for linux-5.19: - The h8300 architecture is retired after it has been effectively unmaintained for a number of years. This is the last architecture we supported that has no MMU implementation, but there are still a few architectures (arm, m68k, riscv, sh and xtensa) that support CPUs with and without an MMU. - A series to add a generic ticket spinlock that can be shared by most architectures with a working cmpxchg or ll/sc type atomic, including the conversion of riscv, csky and openrisc. This series is also a prerequisite for the loongarch64 architecture port that will come as a separate pull request. - A cleanup of some exported uapi header files to ensure they can be included from user space without relying on other kernel headers" * tag 'asm-generic-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: h8300: remove stale bindings and symlink sparc: add asm/stat.h to UAPI compile-test coverage powerpc: add asm/stat.h to UAPI compile-test coverage mips: add asm/stat.h to UAPI compile-test coverage riscv: add linux/bpf_perf_event.h to UAPI compile-test coverage kbuild: prevent exported headers from including <stdlib.h>, <stdbool.h> agpgart.h: do not include <stdlib.h> from exported header csky: Move to generic ticket-spinlock RISC-V: Move to queued RW locks RISC-V: Move to generic spinlocks openrisc: Move to ticket-spinlock asm-generic: qrwlock: Document the spinlock fairness requirements asm-generic: qspinlock: Indicate the use of mixed-size atomics asm-generic: ticket-lock: New generic ticket-based spinlock remove the h8300 architecture
2022-05-01xtensa: enable ARCH_HAS_DEBUG_VM_PGTABLEMax Filippov
xtensa kernels successfully build and run with CONFIG_DEBUG_VM_PGTABLE=y, enable arch support for it. Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: enable HAVE_VIRT_CPU_ACCOUNTING_GENMax Filippov
There's no direct cputime_t manipulation in the xtensa arch code, so generic virt CPU accounting may be enabled. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-05-01xtensa: enable context trackingMax Filippov
Put user exit context tracking call on the common kernel entry/exit path (function calls are impossible at earlier kernel entry stages because PS.EXCM is not cleared yet). Put user entry context tracking call on the user exit path. Syscalls go through this common code too, so nothing specific needs to be done for them. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2022-04-04Merge branch 'remove-h8300' of git://git.infradead.org/users/hch/misc into ↵Arnd Bergmann
asm-generic * 'remove-h8300' of git://git.infradead.org/users/hch/misc: remove the h8300 architecture This is clearly the least actively maintained architecture we have at the moment, and probably the least useful. It is now the only one that does not support MMUs at all, and most of the boards only support 4MB of RAM, out of which the defconfig kernel needs more than half just for .text/.data. Guenter Roeck did the original patch to remove the architecture in 2013 after it had already been obsolete for a while, and Yoshinori Sato brought it back in a much more modern form in 2015. Looking at the git history since the reinstantiation, it's clear that almost all commits in the tree are build fixes or cross-architecture cleanups: $ git log --no-merges --format=%an v4.5.. arch/h8300/ | sort | uniq -c | sort -rn | head -n 12 25 Masahiro Yamada 18 Christoph Hellwig 14 Mike Rapoport 9 Arnd Bergmann 8 Mark Rutland 7 Peter Zijlstra 6 Kees Cook 6 Ingo Molnar 6 Al Viro 5 Randy Dunlap 4 Yury Norov Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-03-07nds32: Remove the architectureAlan Kao
The nds32 architecture, also known as AndeStar V3, is a custom 32-bit RISC target designed by Andes Technologies. Support was added to the kernel in 2016 as the replacement RISC-V based V5 processors were already announced, and maintained by (current or former) Andes employees. As explained by Alan Kao, new customers are now all using RISC-V, and all known nds32 users are already on longterm stable kernels provided by Andes, with no development work going into mainline support any more. While the port is still in a reasonably good shape, it only gets worse over time without active maintainers, so it seems best to remove it before it becomes unusable. As always, if it turns out that there are mainline users after all, and they volunteer to maintain the port in the future, the removal can be reverted. Link: https://lore.kernel.org/linux-mm/YhdWNLUhk+x9RAzU@yamatobi.andestech.com/ Link: https://lore.kernel.org/lkml/20220302065213.82702-1-alankao@andestech.com/ Link: https://www.andestech.com/en/products-solutions/andestar-architecture/ Signed-off-by: Alan Kao <alankao@andestech.com> [arnd: rewrite changelog to provide more background] Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-02-23remove the h8300 architectureChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2021-12-17ARM: 9158/1: leave it to core code to manage thread_info::cpuArd Biesheuvel
Since commit bcf9033e5449 ("sched: move CPU field back into thread_info if THREAD_INFO_IN_TASK=y"), the CPU field in thread_info went back to being managed by the core code, so we no longer have to keep it in sync in arch code. While at it, mark THREAD_INFO_IN_TASK as done for ARM in the documentation. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-11-01parisc: Move thread_info into task structHelge Deller
This implements the CONFIG_THREAD_INFO_IN_TASK option. With this change: - before thread_info was part of the stack and located at the beginning of the stack - now the thread_info struct is moved and located inside the task_struct structure - the stack is allocated and handled like the major other platforms - drop the cpu field of thread_info and use instead the one in task_struct Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Sven Schnelle <svens@stackframe.org>
2021-09-11Merge tag 'riscv-for-linus-5.15-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: - A pair of defconfig additions, for NVMe and the EFI filesystem localization options. - A larger address space for stack randomization. - A cleanup to our install rules. - A DTS update for the Microchip Icicle board, to fix the serial console. - Support for build-time table sorting, which allows us to have __ex_table read-only. * tag 'riscv-for-linus-5.15-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: Move EXCEPTION_TABLE to RO_DATA segment riscv: Enable BUILDTIME_TABLE_SORT riscv: dts: microchip: mpfs-icicle: Fix serial console riscv: move the (z)install rules to arch/riscv/Makefile riscv: Improve stack randomisation on RV64 riscv: defconfig: enable NLS_CODEPAGE_437, NLS_ISO8859_1 riscv: defconfig: enable BLK_DEV_NVME
2021-09-10riscv: Improve stack randomisation on RV64Kefeng Wang
This enlarges the bits availiable for stack randomisation on RV64 from the default of 8MiB to 1GiB, to match arm64 and x86. Also, update the documentation to reflect our support for stack randomisation. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> [Palmer: commit text] Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-08-24Documentation/features/vm: correct huge-vmap APIsMark Rutland
In commit: bbc180a5adb05ee8 ("mm: HUGE_VMAP arch support cleanup") We replaced: * ioremap_pud_enabled() with arch_vmap_pud_supported() * ioremap_pmd_enabled() with arch_vmap_pmd_supported() Update the documentation accordingly. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20210817091621.16799-1-mark.rutland@arm.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-08-12Documentation/features/vm: riscv supports THP nowJisheng Zhang
After commit e88b333142e4 ("riscv: mm: add THP support on 64-bit"), riscv can support THP. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Link: https://lore.kernel.org/r/20210805002739.23f44d2d@xhacker Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-07-15Documentation/features: Add THREAD_INFO_IN_TASK feature matrixIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/YN2nhV5F0hBVNPuX@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-07-15Documentation/features: Update the ARCH_HAS_TICK_BROADCAST entryIngo Molnar
Risc-V gained support recently. Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/YN2nqOVHgGDt4Iid@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-04-30Merge tag 'powerpc-5.13-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Enable KFENCE for 32-bit. - Implement EBPF for 32-bit. - Convert 32-bit to do interrupt entry/exit in C. - Convert 64-bit BookE to do interrupt entry/exit in C. - Changes to our signal handling code to use user_access_begin/end() more extensively. - Add support for time namespaces (CONFIG_TIME_NS) - A series of fixes that allow us to reenable STRICT_KERNEL_RWX. - Other smaller features, fixes & cleanups. Thanks to Alexey Kardashevskiy, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Bixuan Cui, Cédric Le Goater, Chen Huang, Chris Packham, Christophe Leroy, Christopher M. Riedl, Colin Ian King, Dan Carpenter, Daniel Axtens, Daniel Henrique Barboza, David Gibson, Davidlohr Bueso, Denis Efremov, dingsenjie, Dmitry Safonov, Dominic DeMarco, Fabiano Rosas, Ganesh Goudar, Geert Uytterhoeven, Geetika Moolchandani, Greg Kurz, Guenter Roeck, Haren Myneni, He Ying, Jiapeng Chong, Jordan Niethe, Laurent Dufour, Lee Jones, Leonardo Bras, Li Huafei, Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Nathan Chancellor, Nathan Lynch, Nicholas Piggin, Oliver O'Halloran, Paul Menzel, Pu Lehui, Randy Dunlap, Ravi Bangoria, Rosen Penev, Russell Currey, Santosh Sivaraj, Sebastian Andrzej Siewior, Segher Boessenkool, Shivaprasad G Bhat, Srikar Dronamraju, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thomas Gleixner, Tony Ambardar, Tyrel Datwyler, Vaibhav Jain, Vincenzo Frascino, Xiongwei Song, Yang Li, Yu Kuai, and Zhang Yunkai. * tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (302 commits) powerpc/signal32: Fix erroneous SIGSEGV on RT signal return powerpc: Avoid clang uninitialized warning in __get_user_size_allowed powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe powerpc/kvm: Fix build error when PPC_MEM_KEYS/PPC_PSERIES=n powerpc/kasan: Fix shadow start address with modules powerpc/kernel/iommu: Use largepool as a last resort when !largealloc powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs powerpc/44x: fix spelling mistake in Kconfig "varients" -> "variants" powerpc/iommu: Annotate nested lock for lockdep powerpc/iommu: Do not immediately panic when failed IOMMU table allocation powerpc/iommu: Allocate it_map by vmalloc selftests/powerpc: remove unneeded semicolon powerpc/64s: remove unneeded semicolon powerpc/eeh: remove unneeded semicolon powerpc/selftests: Add selftest to test concurrent perf/ptrace events powerpc/selftests/perf-hwbreak: Add testcases for 2nd DAWR powerpc/selftests/perf-hwbreak: Coalesce event creation code powerpc/selftests/ptrace-hwbreak: Add testcases for 2nd DAWR powerpc/configs: Add IBMVNIC to some 64-bit configs selftests/powerpc: Add uaccess flush test ...
2021-03-31powerpc/mm: Revert "powerpc/mm: Remove DEBUG_VM_PGTABLE support on powerpc"Aneesh Kumar K.V
This reverts commit 675bceb097e6 ("powerpc/mm: Remove DEBUG_VM_PGTABLE support on powerpc") All the related issues are fixed as of commit: f14312e1ed1e ("mm/debug_vm_pgtable: avoid doing memory allocation with pgtable_t mapped.") Hence re-enable it. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210318034855.74513-1-aneesh.kumar@linux.ibm.com
2021-03-15Documentation/features: mark BATCHED_UNMAP_TLB_FLUSH doesn't apply to ARM64Barry Song
BATCHED_UNMAP_TLB_FLUSH is used on x86 to do batched tlb shootdown by sending one IPI to TLB flush all entries after unmapping pages rather than sending an IPI to flush each individual entry. On arm64, tlb shootdown is done by hardware. Flush instructions are innershareable. The local flushes are limited to the boot (1 per CPU) and when a task is getting a new ASID. So marking this feature as "TODO" is not proper. ".." isn't good as well. So this patch adds a "N/A" for this kind of features which are not needed on some architectures. Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Acked-by: Will Deacon <will@kernel.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210223003230.11976-1-song.bao.hua@hisilicon.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-02-25Documentation: features: refresh feature listArnd Bergmann
Run the update script to document the recent feature additions on riscv, mips and csky. Fixes: c109f42450ec ("csky: Add kmemleak support") Fixes: 8b3165e54566 ("MIPS: Enable GCOV") Fixes: 1ddc96bd42da ("MIPS: kernel: Support extracting off-line stack traces from user-space with perf") Fixes: 74784081aac8 ("riscv: Add uprobes supported") Fixes: 829adda597fe ("riscv: Add KPROBES_ON_FTRACE supported") Fixes: c22b0bcb1dd0 ("riscv: Add kprobes supported") Fixes: dcdc7a53a890 ("RISC-V: Implement ptrace regs and stack API") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20210225142841.3385428-2-arnd@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-02-25Documentation: features: remove c6x referencesArnd Bergmann
The references to arch/c6x are obsolete now that the architecture is gone. Remove them. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20210225142841.3385428-1-arnd@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>