OpenCloudOS-Kernel/lib/test_bitops.c

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lib: make a test module with set/clear bit Test some bit clears/sets to make sure assembly doesn't change, and that the set_bit and clear_bit functions work and don't cause sparse warnings. Instruct Kbuild to build this file with extra warning level -Wextra, to catch new issues, and also doesn't hurt to build with C=1. This was used to test changes to arch/x86/include/asm/bitops.h. In particular, sparse (C=1) was very concerned when the last bit before a natural boundary, like 7, or 31, was being tested, as this causes sign extension (0xffffff7f) for instance when clearing bit 7. Recommended usage: make defconfig scripts/config -m CONFIG_TEST_BITOPS make modules_prepare make C=1 W=1 lib/test_bitops.ko objdump -S -d lib/test_bitops.ko insmod lib/test_bitops.ko rmmod lib/test_bitops.ko <check dmesg>, there should be no compiler/sparse warnings and no error messages in log. Link: http://lkml.kernel.org/r/20200310221747.2848474-2-jesse.brandeburg@intel.com Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> CcL Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2020 Intel Corporation
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/module.h>
#include <linux/printk.h>
/* a tiny module only meant to test
*
* set/clear_bit
* get_count_order/long
*/
lib: make a test module with set/clear bit Test some bit clears/sets to make sure assembly doesn't change, and that the set_bit and clear_bit functions work and don't cause sparse warnings. Instruct Kbuild to build this file with extra warning level -Wextra, to catch new issues, and also doesn't hurt to build with C=1. This was used to test changes to arch/x86/include/asm/bitops.h. In particular, sparse (C=1) was very concerned when the last bit before a natural boundary, like 7, or 31, was being tested, as this causes sign extension (0xffffff7f) for instance when clearing bit 7. Recommended usage: make defconfig scripts/config -m CONFIG_TEST_BITOPS make modules_prepare make C=1 W=1 lib/test_bitops.ko objdump -S -d lib/test_bitops.ko insmod lib/test_bitops.ko rmmod lib/test_bitops.ko <check dmesg>, there should be no compiler/sparse warnings and no error messages in log. Link: http://lkml.kernel.org/r/20200310221747.2848474-2-jesse.brandeburg@intel.com Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> CcL Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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/* use an enum because thats the most common BITMAP usage */
enum bitops_fun {
BITOPS_4 = 4,
BITOPS_7 = 7,
BITOPS_11 = 11,
BITOPS_31 = 31,
BITOPS_88 = 88,
BITOPS_LAST = 255,
BITOPS_LENGTH = 256
};
static DECLARE_BITMAP(g_bitmap, BITOPS_LENGTH);
static unsigned int order_comb[][2] = {
{0x00000003, 2},
{0x00000004, 2},
{0x00001fff, 13},
{0x00002000, 13},
{0x50000000, 31},
{0x80000000, 31},
{0x80003000, 32},
};
#ifdef CONFIG_64BIT
static unsigned long order_comb_long[][2] = {
{0x0000000300000000, 34},
{0x0000000400000000, 34},
{0x00001fff00000000, 45},
{0x0000200000000000, 45},
{0x5000000000000000, 63},
{0x8000000000000000, 63},
{0x8000300000000000, 64},
};
#endif
lib: make a test module with set/clear bit Test some bit clears/sets to make sure assembly doesn't change, and that the set_bit and clear_bit functions work and don't cause sparse warnings. Instruct Kbuild to build this file with extra warning level -Wextra, to catch new issues, and also doesn't hurt to build with C=1. This was used to test changes to arch/x86/include/asm/bitops.h. In particular, sparse (C=1) was very concerned when the last bit before a natural boundary, like 7, or 31, was being tested, as this causes sign extension (0xffffff7f) for instance when clearing bit 7. Recommended usage: make defconfig scripts/config -m CONFIG_TEST_BITOPS make modules_prepare make C=1 W=1 lib/test_bitops.ko objdump -S -d lib/test_bitops.ko insmod lib/test_bitops.ko rmmod lib/test_bitops.ko <check dmesg>, there should be no compiler/sparse warnings and no error messages in log. Link: http://lkml.kernel.org/r/20200310221747.2848474-2-jesse.brandeburg@intel.com Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> CcL Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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static int __init test_bitops_startup(void)
{
int i;
lib: make a test module with set/clear bit Test some bit clears/sets to make sure assembly doesn't change, and that the set_bit and clear_bit functions work and don't cause sparse warnings. Instruct Kbuild to build this file with extra warning level -Wextra, to catch new issues, and also doesn't hurt to build with C=1. This was used to test changes to arch/x86/include/asm/bitops.h. In particular, sparse (C=1) was very concerned when the last bit before a natural boundary, like 7, or 31, was being tested, as this causes sign extension (0xffffff7f) for instance when clearing bit 7. Recommended usage: make defconfig scripts/config -m CONFIG_TEST_BITOPS make modules_prepare make C=1 W=1 lib/test_bitops.ko objdump -S -d lib/test_bitops.ko insmod lib/test_bitops.ko rmmod lib/test_bitops.ko <check dmesg>, there should be no compiler/sparse warnings and no error messages in log. Link: http://lkml.kernel.org/r/20200310221747.2848474-2-jesse.brandeburg@intel.com Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> CcL Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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pr_warn("Loaded test module\n");
set_bit(BITOPS_4, g_bitmap);
set_bit(BITOPS_7, g_bitmap);
set_bit(BITOPS_11, g_bitmap);
set_bit(BITOPS_31, g_bitmap);
set_bit(BITOPS_88, g_bitmap);
for (i = 0; i < ARRAY_SIZE(order_comb); i++) {
if (order_comb[i][1] != get_count_order(order_comb[i][0]))
pr_warn("get_count_order wrong for %x\n",
order_comb[i][0]);
}
for (i = 0; i < ARRAY_SIZE(order_comb); i++) {
if (order_comb[i][1] != get_count_order_long(order_comb[i][0]))
pr_warn("get_count_order_long wrong for %x\n",
order_comb[i][0]);
}
#ifdef CONFIG_64BIT
for (i = 0; i < ARRAY_SIZE(order_comb_long); i++) {
if (order_comb_long[i][1] !=
get_count_order_long(order_comb_long[i][0]))
pr_warn("get_count_order_long wrong for %lx\n",
order_comb_long[i][0]);
}
#endif
lib: make a test module with set/clear bit Test some bit clears/sets to make sure assembly doesn't change, and that the set_bit and clear_bit functions work and don't cause sparse warnings. Instruct Kbuild to build this file with extra warning level -Wextra, to catch new issues, and also doesn't hurt to build with C=1. This was used to test changes to arch/x86/include/asm/bitops.h. In particular, sparse (C=1) was very concerned when the last bit before a natural boundary, like 7, or 31, was being tested, as this causes sign extension (0xffffff7f) for instance when clearing bit 7. Recommended usage: make defconfig scripts/config -m CONFIG_TEST_BITOPS make modules_prepare make C=1 W=1 lib/test_bitops.ko objdump -S -d lib/test_bitops.ko insmod lib/test_bitops.ko rmmod lib/test_bitops.ko <check dmesg>, there should be no compiler/sparse warnings and no error messages in log. Link: http://lkml.kernel.org/r/20200310221747.2848474-2-jesse.brandeburg@intel.com Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> CcL Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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return 0;
}
static void __exit test_bitops_unstartup(void)
{
int bit_set;
clear_bit(BITOPS_4, g_bitmap);
clear_bit(BITOPS_7, g_bitmap);
clear_bit(BITOPS_11, g_bitmap);
clear_bit(BITOPS_31, g_bitmap);
clear_bit(BITOPS_88, g_bitmap);
bit_set = find_first_bit(g_bitmap, BITOPS_LAST);
if (bit_set != BITOPS_LAST)
pr_err("ERROR: FOUND SET BIT %d\n", bit_set);
pr_warn("Unloaded test module\n");
}
module_init(test_bitops_startup);
module_exit(test_bitops_unstartup);
MODULE_AUTHOR("Jesse Brandeburg <jesse.brandeburg@intel.com>, Wei Yang <richard.weiyang@gmail.com>");
lib: make a test module with set/clear bit Test some bit clears/sets to make sure assembly doesn't change, and that the set_bit and clear_bit functions work and don't cause sparse warnings. Instruct Kbuild to build this file with extra warning level -Wextra, to catch new issues, and also doesn't hurt to build with C=1. This was used to test changes to arch/x86/include/asm/bitops.h. In particular, sparse (C=1) was very concerned when the last bit before a natural boundary, like 7, or 31, was being tested, as this causes sign extension (0xffffff7f) for instance when clearing bit 7. Recommended usage: make defconfig scripts/config -m CONFIG_TEST_BITOPS make modules_prepare make C=1 W=1 lib/test_bitops.ko objdump -S -d lib/test_bitops.ko insmod lib/test_bitops.ko rmmod lib/test_bitops.ko <check dmesg>, there should be no compiler/sparse warnings and no error messages in log. Link: http://lkml.kernel.org/r/20200310221747.2848474-2-jesse.brandeburg@intel.com Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> CcL Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Bit testing module");