overflow, tracing: Define the is_signed_type() macro once

[Eliav Farber]

From: Bart Van Assche <bvanassche at acm.org>

[ Upstream commit 92d23c6e94157739b997cacce151586a0d07bb8a ]

There are two definitions of the is_signed_type() macro: one in
<linux/overflow.h> and a second definition in <linux/trace_events.h>.

As suggested by Linus Torvalds, move the definition of the
is_signed_type() macro into the <linux/compiler.h> header file. Change
the definition of the is_signed_type() macro to make sure that it does
not trigger any sparse warnings with future versions of sparse for
bitwise types. See also:
https://lore.kernel.org/all/CAHk-=whjH6p+qzwUdx5SOVVHjS3WvzJQr6mDUwhEyTf6pJWzaQ@mail.gmail.com/
https://lore.kernel.org/all/CAHk-=wjQGnVfb4jehFR0XyZikdQvCZouE96xR_nnf5kqaM5qqQ@mail.gmail.com/

Cc: Andrew Morton <akpm at linux-foundation.org>
Cc: Arnd Bergmann <arnd at arndb.de>
Cc: Dan Williams <dan.j.williams at intel.com>
Cc: Eric Dumazet <edumazet at google.com>
Cc: Ingo Molnar <mingo at redhat.com>
Cc: Isabella Basso <isabbasso at riseup.net>
Cc: "Jason A. Donenfeld" <Jason at zx2c4.com>
Cc: Josh Poimboeuf <jpoimboe at kernel.org>
Cc: Luc Van Oostenryck <luc.vanoostenryck at gmail.com>
Cc: Masami Hiramatsu <mhiramat at kernel.org>
Cc: Nathan Chancellor <nathan at kernel.org>
Cc: Peter Zijlstra <peterz at infradead.org>
Cc: Rasmus Villemoes <linux at rasmusvillemoes.dk>
Cc: Sander Vanheule <sander at svanheule.net>
Cc: Steven Rostedt <rostedt at goodmis.org>
Cc: Vlastimil Babka <vbabka at suse.cz>
Cc: Yury Norov <yury.norov at gmail.com>
Signed-off-by: Bart Van Assche <bvanassche at acm.org>
Signed-off-by: Kees Cook <keescook at chromium.org>
Link: https://lore.kernel.org/r/20220826162116.1050972-3-bvanassche@acm.org
Signed-off-by: Eliav Farber <farbere at amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 include/linux/compiler.h     |    6 ++++++
 include/linux/overflow.h     |    1 -
 include/linux/trace_events.h |    2 --
 3 files changed, 6 insertions(+), 3 deletions(-)

--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -246,6 +246,12 @@ static inline void *offset_to_ptr(const
 #define __must_be_array(a)	BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
 
 /*
+ * Whether 'type' is a signed type or an unsigned type. Supports scalar types,
+ * bool and also pointer types.
+ */
+#define is_signed_type(type) (((type)(-1)) < (__force type)1)
+
+/*
  * This is needed in functions which generate the stack canary, see
  * arch/x86/kernel/smpboot.c::start_secondary() for an example.
  */
--- a/include/linux/overflow.h
+++ b/include/linux/overflow.h
@@ -29,7 +29,6 @@
  * https://mail-index.netbsd.org/tech-misc/2007/02/05/0000.html -
  * credit to Christian Biere.
  */
-#define is_signed_type(type)       (((type)(-1)) < (type)1)
 #define __type_half_max(type) ((type)1 << (8*sizeof(type) - 1 - is_signed_type(type)))
 #define type_max(T) ((T)((__type_half_max(T) - 1) + __type_half_max(T)))
 #define type_min(T) ((T)((T)-type_max(T)-(T)1))
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -700,8 +700,6 @@ extern int trace_add_event_call(struct t
 extern int trace_remove_event_call(struct trace_event_call *call);
 extern int trace_event_get_offsets(struct trace_event_call *call);
 
-#define is_signed_type(type)	(((type)(-1)) < (type)1)
-
 int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
 int trace_set_clr_event(const char *system, const char *event, int set);
 int trace_array_set_clr_event(struct trace_array *tr, const char *system,


Patches currently in stable-queue which might be from farbere at amazon.com are

queue-5.10/minmax-allow-comparisons-of-int-against-unsigned-char-short.patch
queue-5.10/minmax-add-a-few-more-min_t-max_t-users.patch
queue-5.10/minmax-improve-macro-expansion-and-type-checking.patch
queue-5.10/minmax-fix-indentation-of-__cmp_once-and-__clamp_once.patch
queue-5.10/minmax.h-simplify-the-variants-of-clamp.patch
queue-5.10/minmax-add-in_range-macro.patch
queue-5.10/minmax.h-move-all-the-clamp-definitions-after-the-min-max-ones.patch
queue-5.10/minmax-allow-min-max-clamp-if-the-arguments-have-the-same-signedness.patch
queue-5.10/minmax-don-t-use-max-in-situations-that-want-a-c-constant-expression.patch
queue-5.10/minmax.h-remove-some-defines-that-are-only-expanded-once.patch
queue-5.10/minmax.h-use-build_bug_on_msg-for-the-lo-hi-test-in-clamp.patch
queue-5.10/minmax-simplify-min-max-clamp-implementation.patch
queue-5.10/minmax-deduplicate-__unconst_integer_typeof.patch
queue-5.10/minmax-simplify-and-clarify-min_t-max_t-implementation.patch
queue-5.10/minmax.h-add-whitespace-around-operators-and-after-commas.patch
queue-5.10/minmax-sanity-check-constant-bounds-when-clamping.patch
queue-5.10/minmax-avoid-overly-complicated-constant-expressions-in-vm-code.patch
queue-5.10/minmax-make-generic-min-and-max-macros-available-everywhere.patch
queue-5.10/minmax-fix-up-min3-and-max3-too.patch
queue-5.10/minmax.h-reduce-the-define-expansion-of-min-max-and-clamp.patch
queue-5.10/minmax-fix-header-inclusions.patch
queue-5.10/minmax-introduce-min-max-_array.patch
queue-5.10/btrfs-remove-duplicated-in_range-macro.patch
queue-5.10/overflow-tracing-define-the-is_signed_type-macro-once.patch
queue-5.10/minmax-relax-check-to-allow-comparison-between-unsigned-arguments-and-signed-constants.patch
queue-5.10/minmax-clamp-more-efficiently-by-avoiding-extra-comparison.patch
queue-5.10/minmax.h-update-some-comments.patch