kernel/linux.git/arch/microblaze/mm, branch v6.6.132

microblaze: don't treat zero reserved memory regions as error

2024-09-30T14:25:08+00:00

[ Upstream commit 0075df288dd8a7abfe03b3766176c393063591dd ] Before commit 721f4a6526da ("mm/memblock: remove empty dummy entry") the check for non-zero of memblock.reserved.cnt in mmu_init() would always be true either because memblock.reserved.cnt is initialized to 1 or because there were memory reservations earlier. The removal of dummy empty entry in memblock caused this check to fail because now memblock.reserved.cnt is initialized to 0. Remove the check for non-zero of memblock.reserved.cnt because it's perfectly fine to have an empty memblock.reserved array that early in boot. Reported-by: Guenter Roeck Signed-off-by: Mike Rapoport Reviewed-by: Wei Yang Tested-by: Guenter Roeck Link: https://lore.kernel.org/r/20240729053327.4091459-1-rppt@kernel.org Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin

microblaze: Remove zalloc_maybe_bootmem()

2023-08-23T07:35:22+00:00

Last user of zalloc_maybe_bootmem() was removed by commit 4308e3c9e1ea ("microblaze/PCI: Remove unused allocation & free of PCI host bridge structure") Remove it. Signed-off-by: Christophe Leroy Link: https://lore.kernel.org/r/bfb1601cac24d7ef8e741c83f9301e4a5a87a0b5.1692124505.git.christophe.leroy@csgroup.eu Signed-off-by: Michal Simek

mm: always expand the stack with the mmap write lock held

2023-06-27T16:41:30+00:00

This finishes the job of always holding the mmap write lock when extending the user stack vma, and removes the 'write_locked' argument from the vm helper functions again. For some cases, we just avoid expanding the stack at all: drivers and page pinning really shouldn't be extending any stacks. Let's see if any strange users really wanted that. It's worth noting that architectures that weren't converted to the new lock_mm_and_find_vma() helper function are left using the legacy "expand_stack()" function, but it has been changed to drop the mmap_lock and take it for writing while expanding the vma. This makes it fairly straightforward to convert the remaining architectures. As a result of dropping and re-taking the lock, the calling conventions for this function have also changed, since the old vma may no longer be valid. So it will now return the new vma if successful, and NULL - and the lock dropped - if the area could not be extended. Tested-by: Vegard Nossum Tested-by: John Paul Adrian Glaubitz # ia64 Tested-by: Frank Scheiner # ia64 Signed-off-by: Linus Torvalds

microblaze: fix livelock in uaccess

2023-03-02T17:32:31+00:00

microblaze equivalent of 26178ec11ef3 "x86: mm: consolidate VM_FAULT_RETRY handling" If e.g. get_user() triggers a page fault and a fatal signal is caught, we might end up with handle_mm_fault() returning VM_FAULT_RETRY and not doing anything to page tables. In such case we must *not* return to the faulting insn - that would repeat the entire thing without making any progress; what we need instead is to treat that as failed (user) memory access. Signed-off-by: Al Viro

microblaze/mm: enable ARCH_HAS_VM_GET_PAGE_PROT

2022-07-18T00:14:38+00:00

This enables ARCH_HAS_VM_GET_PAGE_PROT on the platform and exports standard vm_get_page_prot() implementation via DECLARE_VM_GET_PAGE_PROT, which looks up a private and static protection_map[] array. Subsequently all __SXXX and __PXXX macros can be dropped which are no longer needed. Link: https://lkml.kernel.org/r/20220711070600.2378316-9-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual Cc: Michal Simek Cc: Arnd Bergmann Cc: Brian Cain Cc: Catalin Marinas Cc: Christophe Leroy Cc: Christoph Hellwig Cc: Christoph Hellwig Cc: Chris Zankel Cc: "David S. Miller" Cc: Dinh Nguyen Cc: Geert Uytterhoeven Cc: Guo Ren Cc: Heiko Carstens Cc: Huacai Chen Cc: Ingo Molnar Cc: "James E.J. Bottomley" Cc: Jeff Dike Cc: Jonas Bonn Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Paul Mackerras Cc: Paul Walmsley Cc: Richard Henderson Cc: Rich Felker Cc: Russell King Cc: Sam Ravnborg Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Vasily Gorbik Cc: Vineet Gupta Cc: WANG Xuerui Cc: Will Deacon Cc: Yoshinori Sato Signed-off-by: Andrew Morton

mm: avoid unnecessary page fault retires on shared memory types

2022-06-17T02:48:27+00:00

I observed that for each of the shared file-backed page faults, we're very likely to retry one more time for the 1st write fault upon no page. It's because we'll need to release the mmap lock for dirty rate limit purpose with balance_dirty_pages_ratelimited() (in fault_dirty_shared_page()). Then after that throttling we return VM_FAULT_RETRY. We did that probably because VM_FAULT_RETRY is the only way we can return to the fault handler at that time telling it we've released the mmap lock. However that's not ideal because it's very likely the fault does not need to be retried at all since the pgtable was well installed before the throttling, so the next continuous fault (including taking mmap read lock, walk the pgtable, etc.) could be in most cases unnecessary. It's not only slowing down page faults for shared file-backed, but also add more mmap lock contention which is in most cases not needed at all. To observe this, one could try to write to some shmem page and look at "pgfault" value in /proc/vmstat, then we should expect 2 counts for each shmem write simply because we retried, and vm event "pgfault" will capture that. To make it more efficient, add a new VM_FAULT_COMPLETED return code just to show that we've completed the whole fault and released the lock. It's also a hint that we should very possibly not need another fault immediately on this page because we've just completed it. This patch provides a ~12% perf boost on my aarch64 test VM with a simple program sequentially dirtying 400MB shmem file being mmap()ed and these are the time it needs: Before: 650.980 ms (+-1.94%) After: 569.396 ms (+-1.38%) I believe it could help more than that. We need some special care on GUP and the s390 pgfault handler (for gmap code before returning from pgfault), the rest changes in the page fault handlers should be relatively straightforward. Another thing to mention is that mm_account_fault() does take this new fault as a generic fault to be accounted, unlike VM_FAULT_RETRY. I explicitly didn't touch hmm_vma_fault() and break_ksm() because they do not handle VM_FAULT_RETRY even with existing code, so I'm literally keeping them as-is. Link: https://lkml.kernel.org/r/20220530183450.42886-1-peterx@redhat.com Signed-off-by: Peter Xu Acked-by: Geert Uytterhoeven Acked-by: Peter Zijlstra (Intel) Acked-by: Johannes Weiner Acked-by: Vineet Gupta Acked-by: Guo Ren Acked-by: Max Filippov Acked-by: Christian Borntraeger Acked-by: Michael Ellerman (powerpc) Acked-by: Catalin Marinas Reviewed-by: Alistair Popple Reviewed-by: Ingo Molnar Acked-by: Russell King (Oracle) [arm part] Acked-by: Heiko Carstens Cc: Vasily Gorbik Cc: Stafford Horne Cc: David S. Miller Cc: Johannes Berg Cc: Brian Cain Cc: Richard Henderson Cc: Richard Weinberger Cc: Benjamin Herrenschmidt Cc: Thomas Gleixner Cc: Janosch Frank Cc: Albert Ou Cc: Anton Ivanov Cc: Dave Hansen Cc: Borislav Petkov Cc: Sven Schnelle Cc: Andrea Arcangeli Cc: James Bottomley Cc: Al Viro Cc: Alexander Gordeev Cc: Jonas Bonn Cc: Will Deacon Cc: Vlastimil Babka Cc: Michal Simek Cc: Matt Turner Cc: Paul Mackerras Cc: David Hildenbrand Cc: Nicholas Piggin Cc: Palmer Dabbelt Cc: Stefan Kristiansson Cc: Paul Walmsley Cc: Ivan Kokshaysky Cc: Chris Zankel Cc: Hugh Dickins Cc: Dinh Nguyen Cc: Rich Felker Cc: H. Peter Anvin Cc: Andy Lutomirski Cc: Thomas Bogendoerfer Cc: Helge Deller Cc: Yoshinori Sato Signed-off-by: Andrew Morton

microblaze: Add support for reserved memory defined by DT

2022-04-21T08:54:57+00:00

In DT reserved memory nodes can be added as is described by Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt but Microblaze didn't have a support for it. The similar change was done for ARC by commit 1b10cb21d888 ("ARC: add support for reserved memory defined by device tree"). It is pretty much enough to call early_init_fdt_scan_reserved_mem(). Microblaze is not using initial_boot_params that's why there is no need to call early_init_fdt_reserve_self(). Signed-off-by: Michal Simek Link: https://lore.kernel.org/r/da4395776bf0de7207767abcc8a5df05bf411816.1645795048.git.michal.simek@xilinx.com

microblaze: Wire memblock_dump_all()

2022-04-21T08:54:57+00:00

Wire memblock_dump_all() to be able to see the whole memblock allocation. Dumps are enabled by passing memblock=debug via kernel command line. Signed-off-by: Michal Simek Link: https://lore.kernel.org/r/6f480b6010068872f429df69c8894cc3f1f38f46.1645795048.git.michal.simek@xilinx.com

mm: remove redundant check about FAULT_FLAG_ALLOW_RETRY bit

2022-01-15T14:30:27+00:00

Since commit 4064b9827063 ("mm: allow VM_FAULT_RETRY for multiple times") allowed VM_FAULT_RETRY for multiple times, the FAULT_FLAG_ALLOW_RETRY bit of fault_flag will not be changed in the page fault path, so the following check is no longer needed: flags & FAULT_FLAG_ALLOW_RETRY So just remove it. [akpm@linux-foundation.org: coding style fixes] Link: https://lkml.kernel.org/r/20211110123358.36511-1-zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng Cc: Peter Zijlstra Cc: Ingo Molnar Cc: David Hildenbrand Cc: Kirill Shutemov Cc: Peter Xu Cc: Muchun Song Cc: Chengming Zhou Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

microblaze: use is_kernel_text() helper

2021-11-09T18:02:51+00:00

Use is_kernel_text() helper to simplify code. Link: https://lkml.kernel.org/r/20210930071143.63410-11-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Acked-by: Michal Simek Reviewed-by: Sergey Senozhatsky Cc: Alexander Potapenko Cc: Alexei Starovoitov Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Arnd Bergmann Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Christophe Leroy Cc: "David S. Miller" Cc: Dmitry Vyukov Cc: Ingo Molnar Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Michael Ellerman Cc: Paul Mackerras Cc: Petr Mladek Cc: Richard Henderson Cc: Steven Rostedt Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds