user/sven/linux.git/include/linux/percpu.h, branch v6.1.85

locking: Introduce __cleanup() based infrastructure

2024-02-23T08:12:51Z

commit 54da6a0924311c7cf5015533991e44fb8eb12773 upstream. Use __attribute__((__cleanup__(func))) to build: - simple auto-release pointers using __free() - 'classes' with constructor and destructor semantics for scope-based resource management. - lock guards based on the above classes. Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20230612093537.614161713%40infradead.org Signed-off-by: Greg Kroah-Hartman

mm: percpu: add generic pcpu_populate_pte() function

2022-01-20T06:52:52Z

With NEED_PER_CPU_PAGE_FIRST_CHUNK enabled, we need a function to populate pte, this patch adds a generic pcpu populate pte function, pcpu_populate_pte(), which is marked __weak and used on most architectures, but it is overridden on x86, which has its own implementation. Link: https://lkml.kernel.org/r/20211216112359.103822-5-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: "David S. Miller" Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: "H. Peter Anvin" Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Dennis Zhou Cc: Tejun Heo Cc: Christoph Lameter Cc: Albert Ou Cc: Catalin Marinas Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Thomas Bogendoerfer Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: percpu: add generic pcpu_fc_alloc/free funciton

2022-01-20T06:52:52Z

With the previous patch, we could add a generic pcpu first chunk allocate and free function to cleanup the duplicated definations on each architecture. Link: https://lkml.kernel.org/r/20211216112359.103822-4-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Cc: Thomas Bogendoerfer Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: "David S. Miller" Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: "H. Peter Anvin" Cc: Greg Kroah-Hartman Cc: Dennis Zhou Cc: Tejun Heo Cc: Christoph Lameter Cc: Albert Ou Cc: Catalin Marinas Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: "Rafael J. Wysocki" Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: percpu: add pcpu_fc_cpu_to_node_fn_t typedef

2022-01-20T06:52:52Z

Add pcpu_fc_cpu_to_node_fn_t and pass it into pcpu_fc_alloc_fn_t, pcpu first chunk allocation will call it to alloc memblock on the corresponding node by it, this is prepare for the next patch. Link: https://lkml.kernel.org/r/20211216112359.103822-3-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Cc: Thomas Bogendoerfer Cc: Michael Ellerman Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: "David S. Miller" Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: "H. Peter Anvin" Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Dennis Zhou Cc: Tejun Heo Cc: Christoph Lameter Cc: Albert Ou Cc: Catalin Marinas Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'printk-for-5.16-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

2021-11-18T18:50:45Z

Pull printk fixes from Petr Mladek: - Try to flush backtraces from other CPUs also on the local one. This was a regression caused by printk_safe buffers removal. - Remove header dependency warning. * tag 'printk-for-5.16-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: printk: Remove printk.h inclusion in percpu.h printk: restore flushing of NMI buffers on remote CPUs after NMI backtraces

printk: Remove printk.h inclusion in percpu.h

2021-11-15T14:03:32Z

After the commit 42a0bb3f7138 ("printk/nmi: generic solution for safe printk in NMI") the printk.h is not needed anymore in percpu.h. Moreover `make headerdep` complains (an excerpt) In file included from linux/printk.h, from linux/dynamic_debug.h:188 from linux/printk.h:559 <-- here from linux/percpu.h:9 from linux/idr.h:17 include/net/9p/client.h:13: warning: recursive header inclusion Yeah, it's not a root cause of this, but removing will help to reduce the noise. Fixes: 42a0bb3f7138 ("printk/nmi: generic solution for safe printk in NMI") Signed-off-by: Andy Shevchenko Acked-by: Dennis Zhou Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20211112140749.80042-1-andriy.shevchenko@linux.intel.com

percpu: add __alloc_size attributes for better bounds checking

2021-11-06T20:30:34Z

As already done in GrapheneOS, add the __alloc_size attribute for appropriate percpu allocator interfaces, to provide additional hinting for better bounds checking, assisting CONFIG_FORTIFY_SOURCE and other compiler optimizations. Note that due to the implementation of the percpu API, this is unlikely to ever actually provide compile-time checking beyond very simple non-SMP builds. But, since they are technically allocators, mark them as such. Link: https://lkml.kernel.org/r/20210930222704.2631604-9-keescook@chromium.org Signed-off-by: Kees Cook Co-developed-by: Daniel Micay Signed-off-by: Daniel Micay Acked-by: Dennis Zhou Cc: Tejun Heo Cc: Christoph Lameter Cc: Andy Whitcroft Cc: David Rientjes Cc: Dwaipayan Ray Cc: Joe Perches Cc: Joonsoo Kim Cc: Lukas Bulwahn Cc: Miguel Ojeda Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Pekka Enberg Cc: Vlastimil Babka Cc: Alexandre Bounine Cc: Gustavo A. R. Silva Cc: Ira Weiny Cc: Jing Xiangfeng Cc: John Hubbard Cc: kernel test robot Cc: Matt Porter Cc: Randy Dunlap Cc: Souptick Joarder Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

percpu: Make pcpu_setup_first_chunk() void function

2019-07-04T15:05:52Z

pcpu_setup_first_chunk() will panic or BUG_ON if the are some error and doesn't return any error, hence it can be defined to return void. Reported-by: kbuild test robot Signed-off-by: Kefeng Wang Signed-off-by: Dennis Zhou [Dennis: fixed kbuild warning for pcpu_page_first_chunk()]

percpu: set PCPU_BITMAP_BLOCK_SIZE to PAGE_SIZE

2019-03-13T19:25:31Z

Previously, block size was flexible based on the constraint that the GCD(PCPU_BITMAP_BLOCK_SIZE, PAGE_SIZE) > 1. However, this carried the overhead that keeping a floating number of populated free pages required scanning over the free regions of a chunk. Setting the block size to be fixed at PAGE_SIZE lets us know when an empty page becomes used as we will break a full contig_hint of a block. This means we no longer have to scan the whole chunk upon breaking a contig_hint which empty page management piggybacked off. A later patch takes advantage of this to optimize the allocation path by only scanning forward using the scan_hint introduced later too. Signed-off-by: Dennis Zhou Reviewed-by: Peng Fan

/proc/meminfo: add percpu populated pages count

2018-08-22T17:52:45Z

Currently, percpu memory only exposes allocation and utilization information via debugfs. This more or less is only really useful for understanding the fragmentation and allocation information at a per-chunk level with a few global counters. This is also gated behind a config. BPF and cgroup, for example, have seen an increase in use causing increased use of percpu memory. Let's make it easier for someone to identify how much memory is being used. This patch adds the "Percpu" stat to meminfo to more easily look up how much percpu memory is in use. This number includes the cost for all allocated backing pages and not just insight at the per a unit, per chunk level. Metadata is excluded. I think excluding metadata is fair because the backing memory scales with the numbere of cpus and can quickly outweigh the metadata. It also makes this calculation light. Link: http://lkml.kernel.org/r/20180807184723.74919-1-dennisszhou@gmail.com Signed-off-by: Dennis Zhou Acked-by: Tejun Heo Acked-by: Roman Gushchin Reviewed-by: Andrew Morton Acked-by: David Rientjes Acked-by: Vlastimil Babka Cc: Johannes Weiner Cc: Christoph Lameter Cc: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds