From b296a6d53339a79082c1d2c1761e948e8b3def69 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Thu, 15 Oct 2020 20:10:21 -0700 Subject: kernel.h: split out min()/max() et al. helpers kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt to start cleaning it up by splitting out min()/max() et al. helpers. At the same time convert users in header and lib folder to use new header. Though for time being include new header back to kernel.h to avoid twisted indirected includes for other existing users. Signed-off-by: Andy Shevchenko Signed-off-by: Andrew Morton Cc: "Rafael J. Wysocki" Cc: Steven Rostedt Cc: Rasmus Villemoes Cc: Joe Perches Cc: Linus Torvalds Link: https://lkml.kernel.org/r/20200910164152.GA1891694@smile.fi.intel.com Signed-off-by: Linus Torvalds --- include/linux/kernel.h | 150 +------------------------------------------------ 1 file changed, 1 insertion(+), 149 deletions(-) (limited to 'include/linux/kernel.h') diff --git a/include/linux/kernel.h b/include/linux/kernel.h index e4aa29b1ad62..c629215fdad9 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -833,155 +834,6 @@ ftrace_vprintk(const char *fmt, va_list ap) static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } #endif /* CONFIG_TRACING */ -/* - * min()/max()/clamp() macros must accomplish three things: - * - * - avoid multiple evaluations of the arguments (so side-effects like - * "x++" happen only once) when non-constant. - * - perform strict type-checking (to generate warnings instead of - * nasty runtime surprises). See the "unnecessary" pointer comparison - * in __typecheck(). - * - retain result as a constant expressions when called with only - * constant expressions (to avoid tripping VLA warnings in stack - * allocation usage). - */ -#define __typecheck(x, y) \ - (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) - -/* - * This returns a constant expression while determining if an argument is - * a constant expression, most importantly without evaluating the argument. - * Glory to Martin Uecker - */ -#define __is_constexpr(x) \ - (sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8))) - -#define __no_side_effects(x, y) \ - (__is_constexpr(x) && __is_constexpr(y)) - -#define __safe_cmp(x, y) \ - (__typecheck(x, y) && __no_side_effects(x, y)) - -#define __cmp(x, y, op) ((x) op (y) ? (x) : (y)) - -#define __cmp_once(x, y, unique_x, unique_y, op) ({ \ - typeof(x) unique_x = (x); \ - typeof(y) unique_y = (y); \ - __cmp(unique_x, unique_y, op); }) - -#define __careful_cmp(x, y, op) \ - __builtin_choose_expr(__safe_cmp(x, y), \ - __cmp(x, y, op), \ - __cmp_once(x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y), op)) - -/** - * min - return minimum of two values of the same or compatible types - * @x: first value - * @y: second value - */ -#define min(x, y) __careful_cmp(x, y, <) - -/** - * max - return maximum of two values of the same or compatible types - * @x: first value - * @y: second value - */ -#define max(x, y) __careful_cmp(x, y, >) - -/** - * min3 - return minimum of three values - * @x: first value - * @y: second value - * @z: third value - */ -#define min3(x, y, z) min((typeof(x))min(x, y), z) - -/** - * max3 - return maximum of three values - * @x: first value - * @y: second value - * @z: third value - */ -#define max3(x, y, z) max((typeof(x))max(x, y), z) - -/** - * min_not_zero - return the minimum that is _not_ zero, unless both are zero - * @x: value1 - * @y: value2 - */ -#define min_not_zero(x, y) ({ \ - typeof(x) __x = (x); \ - typeof(y) __y = (y); \ - __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); }) - -/** - * clamp - return a value clamped to a given range with strict typechecking - * @val: current value - * @lo: lowest allowable value - * @hi: highest allowable value - * - * This macro does strict typechecking of @lo/@hi to make sure they are of the - * same type as @val. See the unnecessary pointer comparisons. - */ -#define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi) - -/* - * ..and if you can't take the strict - * types, you can specify one yourself. - * - * Or not use min/max/clamp at all, of course. - */ - -/** - * min_t - return minimum of two values, using the specified type - * @type: data type to use - * @x: first value - * @y: second value - */ -#define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <) - -/** - * max_t - return maximum of two values, using the specified type - * @type: data type to use - * @x: first value - * @y: second value - */ -#define max_t(type, x, y) __careful_cmp((type)(x), (type)(y), >) - -/** - * clamp_t - return a value clamped to a given range using a given type - * @type: the type of variable to use - * @val: current value - * @lo: minimum allowable value - * @hi: maximum allowable value - * - * This macro does no typechecking and uses temporary variables of type - * @type to make all the comparisons. - */ -#define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi) - -/** - * clamp_val - return a value clamped to a given range using val's type - * @val: current value - * @lo: minimum allowable value - * @hi: maximum allowable value - * - * This macro does no typechecking and uses temporary variables of whatever - * type the input argument @val is. This is useful when @val is an unsigned - * type and @lo and @hi are literals that will otherwise be assigned a signed - * integer type. - */ -#define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi) - - -/** - * swap - swap values of @a and @b - * @a: first value - * @b: second value - */ -#define swap(a, b) \ - do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) - /* This counts to 12. Any more, it will return 13th argument. */ #define __COUNT_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _n, X...) _n #define COUNT_ARGS(X...) __COUNT_ARGS(, ##X, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) -- cgit v1.2.3 From 33def8498fdde180023444b08e12b72a9efed41d Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Wed, 21 Oct 2020 19:36:07 -0700 Subject: treewide: Convert macro and uses of __section(foo) to __section("foo") Use a more generic form for __section that requires quotes to avoid complications with clang and gcc differences. Remove the quote operator # from compiler_attributes.h __section macro. Convert all unquoted __section(foo) uses to quoted __section("foo"). Also convert __attribute__((section("foo"))) uses to __section("foo") even if the __attribute__ has multiple list entry forms. Conversion done using the script at: https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl Signed-off-by: Joe Perches Reviewed-by: Nick Desaulniers Reviewed-by: Miguel Ojeda Signed-off-by: Linus Torvalds --- include/linux/kernel.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/kernel.h') diff --git a/include/linux/kernel.h b/include/linux/kernel.h index c629215fdad9..2f05e9128201 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -729,7 +729,7 @@ do { \ #define do_trace_printk(fmt, args...) \ do { \ static const char *trace_printk_fmt __used \ - __attribute__((section("__trace_printk_fmt"))) = \ + __section("__trace_printk_fmt") = \ __builtin_constant_p(fmt) ? fmt : NULL; \ \ __trace_printk_check_format(fmt, ##args); \ @@ -773,7 +773,7 @@ int __trace_printk(unsigned long ip, const char *fmt, ...); #define trace_puts(str) ({ \ static const char *trace_printk_fmt __used \ - __attribute__((section("__trace_printk_fmt"))) = \ + __section("__trace_printk_fmt") = \ __builtin_constant_p(str) ? str : NULL; \ \ if (__builtin_constant_p(str)) \ @@ -795,7 +795,7 @@ extern void trace_dump_stack(int skip); do { \ if (__builtin_constant_p(fmt)) { \ static const char *trace_printk_fmt __used \ - __attribute__((section("__trace_printk_fmt"))) = \ + __section("__trace_printk_fmt") = \ __builtin_constant_p(fmt) ? fmt : NULL; \ \ __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ -- cgit v1.2.3