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2020-06-11Merge tag 'riscv-for-linus-5.8-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: - Kconfig select statements are now sorted alphanumerically - first-level interrupts are now handled via a full irqchip driver - CPU hotplug is fixed - vDSO calls now use the common vDSO infrastructure * tag 'riscv-for-linus-5.8-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: set the permission of vdso_data to read-only riscv: use vDSO common flow to reduce the latency of the time-related functions riscv: fix build warning of missing prototypes RISC-V: Don't mark init section as non-executable RISC-V: Force select RISCV_INTC for CONFIG_RISCV RISC-V: Remove do_IRQ() function clocksource/drivers/timer-riscv: Use per-CPU timer interrupt irqchip: RISC-V per-HART local interrupt controller driver RISC-V: Rename and move plic_find_hart_id() to arch directory RISC-V: self-contained IPI handling routine RISC-V: Sort select statements alphanumerically
2020-06-10riscv: set the permission of vdso_data to read-onlyVincent Chen
The original vdso_data page is empty, so the permission of the vdso_data page can be the same with the vdso text page. After introducing the vDSO common flow, the vdso_data is not empty and the permission should be changed to read-only. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-10riscv: use vDSO common flow to reduce the latency of the time-related functionsVincent Chen
Even if RISC-V has supported the vDSO feature, the latency of the functions for obtaining the system time is still expensive. It is because these functions still trigger a corresponding system call in the process, which slows down the response time. If we want to remove the system call to reduce the latency, the kernel should have the ability to output the system clock information to userspace. This patch introduces the vDSO common flow to enable the kernel to achieve the above feature and uses "rdtime" instruction to obtain the current time in the user space. Under this condition, the latency cost by the ecall from U-mode to S-mode can be eliminated. After applying this patch, the latency of gettimeofday() measured on the HiFive unleashed board can be reduced by %61. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-09mmap locking API: use coccinelle to convert mmap_sem rwsem call sitesMichel Lespinasse
This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-28riscv: add missing header file includesPaul Walmsley
sparse identifies several missing prototypes caused by missing preprocessor include directives: arch/riscv/kernel/cpufeature.c:16:6: warning: symbol 'has_fpu' was not declared. Should it be static? arch/riscv/kernel/process.c:26:6: warning: symbol 'arch_cpu_idle' was not declared. Should it be static? arch/riscv/kernel/reset.c:15:6: warning: symbol 'pm_power_off' was not declared. Should it be static? arch/riscv/kernel/syscall_table.c:15:6: warning: symbol 'sys_call_table' was not declared. Should it be static? arch/riscv/kernel/traps.c:149:13: warning: symbol 'trap_init' was not declared. Should it be static? arch/riscv/kernel/vdso.c:54:5: warning: symbol 'arch_setup_additional_pages' was not declared. Should it be static? arch/riscv/kernel/smp.c:64:6: warning: symbol 'arch_match_cpu_phys_id' was not declared. Should it be static? arch/riscv/kernel/module-sections.c:89:5: warning: symbol 'module_frob_arch_sections' was not declared. Should it be static? arch/riscv/mm/context.c:42:6: warning: symbol 'switch_mm' was not declared. Should it be static? Fix by including the appropriate header files in the appropriate source files. This patch should have no functional impact. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-10-28riscv: mark some code and data as file-staticPaul Walmsley
Several functions and arrays which are only used in the files in which they are declared are missing "static" qualifiers. Warnings for these symbols are reported by sparse: arch/riscv/kernel/vdso.c:28:18: warning: symbol 'vdso_data' was not declared. Should it be static? arch/riscv/mm/sifive_l2_cache.c:145:12: warning: symbol 'sifive_l2_init' was not declared. Should it be static? Resolve these warnings by marking them as static. This version incorporates feedback from Greentime Hu <greentime.hu@sifive.com>. Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Greentime Hu <greentime.hu@sifive.com>
2019-07-01riscv: Remove gate area stubsAndy Lutomirski
Since commit a6c19dfe3994 ("arm64,ia64,ppc,s390,sh,tile,um,x86,mm: remove default gate area"), which predates riscv's inclusion in Linux by almost three years, the default behavior wrt the gate area is sane. Remove riscv's gate area stubs. Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: linux-riscv@lists.infradead.org Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-05riscv/vdso: don't clear PG_reservedDavid Hildenbrand
The VDSO is part of the kernel image and therefore the struct pages are marked as reserved during boot. As we install a special mapping, the actual struct pages will never be exposed to MM via the page tables. We can therefore leave the pages marked as reserved. Link: http://lkml.kernel.org/r/20190114125903.24845-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Palmer Dabbelt <palmer@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Michal Hocko <mhocko@kernel.org> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-30riscv: remove redundant unlikely()Tobias Klauser
IS_ERR_VALUE() already implies unlikely(), so it can be omitted. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-09-26RISC-V: Init and Halt CodePalmer Dabbelt
This contains the various __init C functions, the initial assembly kernel entry point, and the code to reset the system. When a file was init-related this patch contains the entire file. Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>