user/sven/linux.git/include/linux/cpumask.h, branch v5.15.80

drivers/base: Fix unsigned comparison to -1 in CPUMAP_FILE_MAX_BYTES

2022-09-28T09:11:40Z

commit d7f06bdd6ee87fbefa05af5f57361d85e7715b11 upstream. As PAGE_SIZE is unsigned long, -1 > PAGE_SIZE when NR_CPUS <= 3. This leads to very large file sizes: topology$ ls -l total 0 -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 core_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 core_cpus_list -r--r--r-- 1 root root 4096 Sep 5 10:58 core_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 10:10 core_siblings -r--r--r-- 1 root root 4096 Sep 5 11:59 core_siblings_list -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 die_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 die_cpus_list -r--r--r-- 1 root root 4096 Sep 5 11:59 die_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 11:59 package_cpus -r--r--r-- 1 root root 4096 Sep 5 11:59 package_cpus_list -r--r--r-- 1 root root 4096 Sep 5 10:58 physical_package_id -r--r--r-- 1 root root 18446744073709551615 Sep 5 10:10 thread_siblings -r--r--r-- 1 root root 4096 Sep 5 11:59 thread_siblings_list Adjust the inequality to catch the case when NR_CPUS is configured to a small value. Fixes: 7ee951acd31a ("drivers/base: fix userspace break from using bin_attributes for cpumap and cpulist") Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Yury Norov Cc: stable@vger.kernel.org Cc: feng xiangjun Reported-by: feng xiangjun Signed-off-by: Phil Auld Signed-off-by: Yury Norov Link: https://lore.kernel.org/r/20220906203542.1796629-1-pauld@redhat.com Signed-off-by: Greg Kroah-Hartman

drivers/base: fix userspace break from using bin_attributes for cpumap and cpulist

2022-08-31T15:16:35Z

[ Upstream commit 7ee951acd31a88f941fd6535fbdee3a1567f1d63 ] Using bin_attributes with a 0 size causes fstat and friends to return that 0 size. This breaks userspace code that retrieves the size before reading the file. Rather than reverting 75bd50fa841 ("drivers/base/node.c: use bin_attribute to break the size limitation of cpumap ABI") let's put in a size value at compile time. For cpulist the maximum size is on the order of NR_CPUS * (ceil(log10(NR_CPUS)) + 1)/2 which for 8192 is 20480 (8192 * 5)/2. In order to get near that you'd need a system with every other CPU on one node. For example: (0,2,4,8, ... ). To simplify the math and support larger NR_CPUS in the future we are using (NR_CPUS * 7)/2. We also set it to a min of PAGE_SIZE to retain the older behavior for smaller NR_CPUS. The cpumap file the size works out to be NR_CPUS/4 + NR_CPUS/32 - 1 (or NR_CPUS * 9/32 - 1) including the ","s. Add a set of macros for these values to cpumask.h so they can be used in multiple places. Apply these to the handful of such files in drivers/base/topology.c as well as node.c. As an example, on an 80 cpu 4-node system (NR_CPUS == 8192): before: -r--r--r--. 1 root root 0 Jul 12 14:08 system/node/node0/cpulist -r--r--r--. 1 root root 0 Jul 11 17:25 system/node/node0/cpumap after: -r--r--r--. 1 root root 28672 Jul 13 11:32 system/node/node0/cpulist -r--r--r--. 1 root root 4096 Jul 13 11:31 system/node/node0/cpumap CONFIG_NR_CPUS = 16384 -r--r--r--. 1 root root 57344 Jul 13 14:03 system/node/node0/cpulist -r--r--r--. 1 root root 4607 Jul 13 14:02 system/node/node0/cpumap The actual number of cpus doesn't matter for the reported size since they are based on NR_CPUS. Fixes: 75bd50fa841d ("drivers/base/node.c: use bin_attribute to break the size limitation of cpumap ABI") Fixes: bb9ec13d156e ("topology: use bin_attribute to break the size limitation of cpumap ABI") Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Yury Norov Cc: stable@vger.kernel.org Acked-by: Yury Norov (for include/linux/cpumask.h) Signed-off-by: Phil Auld Link: https://lore.kernel.org/r/20220715134924.3466194-1-pauld@redhat.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

cpumask: Omit terminating null byte in cpumap_print_{list,bitmask}_to_buf

2021-09-21T15:34:53Z

The changes in the patch series [1] introduced a terminating null byte when reading from cpulist or cpumap sysfs files, for example: $ xxd /sys/devices/system/node/node0/cpulist 00000000: 302d 310a 00 0-1.. Before this change, the output looked as follows: $ xxd /sys/devices/system/node/node0/cpulist 00000000: 302d 310a 0-1. Fix this regression by excluding the terminating null byte from the returned length in cpumap_print_list_to_buf and cpumap_print_bitmask_to_buf. [1] https://lore.kernel.org/all/20210806110251.560-1-song.bao.hua@hisilicon.com/ Fixes: 1fae562983ca ("cpumask: introduce cpumap_print_list/bitmask_to_buf to support large bitmask and list") Acked-by: Barry Song Acked-by: Yury Norov Signed-off-by: Tobias Klauser Link: https://lore.kernel.org/r/20210916222705.13554-1-tklauser@distanz.ch Signed-off-by: Greg Kroah-Hartman

cpumask: introduce cpumap_print_list/bitmask_to_buf to support large bitmask and list

2021-08-13T08:27:49Z

The existing cpumap_print_to_pagebuf() is used by cpu topology and other drivers to export hexadecimal bitmask and decimal list to userspace by sysfs ABI. Right now, those drivers are using a normal attribute for this kind of ABIs. A normal attribute typically has show entry as below: static ssize_t example_dev_show(struct device *dev, struct device_attribute *attr, char *buf) { ... return cpumap_print_to_pagebuf(true, buf, &pmu_mmdc->cpu); } show entry of attribute has no offset and count parameters and this means the file is limited to one page only. cpumap_print_to_pagebuf() API works terribly well for this kind of normal attribute with buf parameter and without offset, count: static inline ssize_t cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask) { return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask), nr_cpu_ids); } The problem is once we have many cpus, we have a chance to make bitmask or list more than one page. Especially for list, it could be as complex as 0,3,5,7,9,...... We have no simple way to know it exact size. It turns out bin_attribute is a way to break this limit. bin_attribute has show entry as below: static ssize_t example_bin_attribute_show(struct file *filp, struct kobject *kobj, struct bin_attribute *attr, char *buf, loff_t offset, size_t count) { ... } With the new offset and count parameters, this makes sysfs ABI be able to support file size more than one page. For example, offset could be >= 4096. This patch introduces cpumap_print_bitmask/list_to_buf() and their bitmap infrastructure bitmap_print_bitmask/list_to_buf() so that those drivers can move to bin_attribute to support large bitmask and list. At the same time, we have to pass those corresponding parameters such as offset, count from bin_attribute to this new API. Cc: Andrew Morton Cc: Andy Shevchenko Cc: Randy Dunlap Cc: Stefano Brivio Cc: Alexander Gordeev Cc: "Ma, Jianpeng" Cc: Yury Norov Cc: Valentin Schneider Cc: Peter Zijlstra Cc: Daniel Bristot de Oliveira Reviewed-by: Jonathan Cameron Signed-off-by: Tian Tao Signed-off-by: Barry Song Link: https://lore.kernel.org/r/20210806110251.560-2-song.bao.hua@hisilicon.com Signed-off-by: Greg Kroah-Hartman

lib: fix spelling mistakes in header files

2021-07-08T18:48:20Z

Fix some spelling mistakes in comments found by "codespell": Hoever ==> However poiter ==> pointer representaion ==> representation uppon ==> upon independend ==> independent aquired ==> acquired mis-match ==> mismatch scrach ==> scratch struture ==> structure Analagous ==> Analogous interation ==> iteration And some were discovered manually by Joe Perches and Christoph Lameter: stroed ==> stored arch independent ==> an architecture independent A example structure for ==> Example structure for Link: https://lkml.kernel.org/r/20210609150027.14805-2-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei Cc: Christoph Lameter Cc: Masami Hiramatsu Cc: Dennis Zhou Cc: Tejun Heo Cc: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'x86-mm-2021-04-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2021-04-29T18:41:43Z

Pull x86 tlb updates from Ingo Molnar: "The x86 MM changes in this cycle were: - Implement concurrent TLB flushes, which overlaps the local TLB flush with the remote TLB flush. In testing this improved sysbench performance measurably by a couple of percentage points, especially if TLB-heavy security mitigations are active. - Further micro-optimizations to improve the performance of TLB flushes" * tag 'x86-mm-2021-04-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: smp: Micro-optimize smp_call_function_many_cond() smp: Inline on_each_cpu_cond() and on_each_cpu() x86/mm/tlb: Remove unnecessary uses of the inline keyword cpumask: Mark functions as pure x86/mm/tlb: Do not make is_lazy dirty for no reason x86/mm/tlb: Privatize cpu_tlbstate x86/mm/tlb: Flush remote and local TLBs concurrently x86/mm/tlb: Open-code on_each_cpu_cond_mask() for tlb_is_not_lazy() x86/mm/tlb: Unify flush_tlb_func_local() and flush_tlb_func_remote() smp: Run functions concurrently in smp_call_function_many_cond()

cpumask: Introduce DYING mask

2021-04-16T15:06:32Z

Introduce a cpumask that indicates (for each CPU) what direction the CPU hotplug is currently going. Notably, it tracks rollbacks. Eg. when an up fails and we do a roll-back down, it will accurately reflect the direction. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Valentin Schneider Link: https://lkml.kernel.org/r/20210310150109.151441252@infradead.org

cpumask: Make cpu_{online,possible,present,active}() inline

2021-04-16T15:06:32Z

Prepare for addition of another mask. Primarily a code movement to avoid having to create more #ifdef, but while there, convert everything with an argument to an inline function. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Valentin Schneider Link: https://lkml.kernel.org/r/20210310150109.045447765@infradead.org

cpumask: Mark functions as pure

2021-03-06T11:59:10Z

cpumask_next_and() and cpumask_any_but() are pure, and marking them as such seems to generate different and presumably better code for native_flush_tlb_multi(). Signed-off-by: Nadav Amit Signed-off-by: Ingo Molnar Reviewed-by: Dave Hansen Link: https://lore.kernel.org/r/20210220231712.2475218-8-namit@vmware.com

sched,rt: Use cpumask_any*_distribute()

2020-11-10T17:39:00Z

Replace a bunch of cpumask_any*() instances with cpumask_any*_distribute(), by injecting this little bit of random in cpu selection, we reduce the chance two competing balance operations working off the same lowest_mask pick the same CPU. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Valentin Schneider Reviewed-by: Daniel Bristot de Oliveira Link: https://lkml.kernel.org/r/20201023102347.190759694@infradead.org