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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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aa5e65dc08
We can see that "Time namespaces are not supported" on LoongArch: (1) clone3 test # cd tools/testing/selftests/clone3 && make && ./clone3 ... # Time namespaces are not supported ok 18 # SKIP Skipping clone3() with CLONE_NEWTIME # Totals: pass:17 fail:0 xfail:0 xpass:0 skip:1 error:0 (2) timens test # cd tools/testing/selftests/timens && make && ./timens ... 1..0 # SKIP Time namespaces are not supported On LoongArch the current kernel does not support CONFIG_TIME_NS which depends on GENERIC_VDSO_TIME_NS, select GENERIC_VDSO_TIME_NS to enable CONFIG_TIME_NS to build kernel/time/namespace.c. Additionally, it needs to define some arch-dependent functions for the timens, such as __arch_get_timens_vdso_data(), arch_get_vdso_data() and vdso_join_timens(). At the same time, modify the layout of vvar to use one page size for generic vdso data, expand another page size for timens vdso data and assign LOONGARCH_VDSO_DATA_SIZE (maybe exceeds a page size if expand in the future) for loongarch vdso data, at last add the callback function vvar_fault() and modify stack_top(). With this patch under CONFIG_TIME_NS: (1) clone3 test # cd tools/testing/selftests/clone3 && make && ./clone3 ... ok 18 [739] Result (0) matches expectation (0) # Totals: pass:18 fail:0 xfail:0 xpass:0 skip:0 error:0 (2) timens test # cd tools/testing/selftests/timens && make && ./timens ... # Totals: pass:10 fail:0 xfail:0 xpass:0 skip:0 error:0 Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
45 lines
850 B
C
45 lines
850 B
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Fast user context implementation of getcpu()
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*/
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#include <asm/vdso.h>
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#include <linux/getcpu.h>
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static __always_inline int read_cpu_id(void)
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{
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int cpu_id;
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__asm__ __volatile__(
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" rdtime.d $zero, %0\n"
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: "=r" (cpu_id)
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:
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: "memory");
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return cpu_id;
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}
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static __always_inline const struct vdso_pcpu_data *get_pcpu_data(void)
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{
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return (struct vdso_pcpu_data *)(get_vdso_data() + VVAR_LOONGARCH_PAGES_START * PAGE_SIZE);
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}
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extern
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int __vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *unused);
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int __vdso_getcpu(unsigned int *cpu, unsigned int *node, struct getcpu_cache *unused)
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{
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int cpu_id;
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const struct vdso_pcpu_data *data;
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cpu_id = read_cpu_id();
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if (cpu)
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*cpu = cpu_id;
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if (node) {
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data = get_pcpu_data();
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*node = data[cpu_id].node;
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}
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return 0;
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}
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