The patch titled
Subject: kernel.h: split out COUNT_ARGS() and CONCATENATE() to args.h
has been added to the -mm mm-nonmm-unstable branch. Its filename is
kernelh-split-out-count_args-and-concatenate-to-argsh.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kernelh-split-out-count_args-and-concatenate-to-argsh.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Subject: kernel.h: split out COUNT_ARGS() and CONCATENATE() to args.h
Date: Fri, 14 Jul 2023 17:22:37 +0300
kernel.h is being used as a dump for all kinds of stuff for a long time.
The COUNT_ARGS() and CONCATENATE() macros may be used in some places
without need of the full kernel.h dependency train with it.
Here is the attempt on cleaning it up by splitting out these macros().
While at it, include new header where it's being used and drop custom
implementation of these macros and document how it works.
Link: https://lkml.kernel.org/r/20230714142237.21836-1-andriy.shevchenko@xxxxxxxxxxxxxxx
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Acked-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Cc: Brendan Higgins <brendan.higgins@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Daniel Latypov <dlatypov@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: David Gow <davidgow@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Lorenzo Pieralisi <lpieralisi@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Cc: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
Cc: Sudeep Holla <sudeep.holla@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/rmwcc.h | 11 +++--------
include/kunit/test.h | 1 +
include/linux/args.h | 28 ++++++++++++++++++++++++++++
include/linux/arm-smccc.h | 27 ++++++++++-----------------
include/linux/genl_magic_struct.h | 8 +++-----
include/linux/kernel.h | 7 -------
include/linux/pci.h | 2 +-
include/trace/bpf_probe.h | 2 ++
8 files changed, 48 insertions(+), 38 deletions(-)
--- a/arch/x86/include/asm/rmwcc.h~kernelh-split-out-count_args-and-concatenate-to-argsh
+++ a/arch/x86/include/asm/rmwcc.h
@@ -2,12 +2,7 @@
#ifndef _ASM_X86_RMWcc
#define _ASM_X86_RMWcc
-/* This counts to 12. Any more, it will return 13th argument. */
-#define __RMWcc_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _n, X...) _n
-#define RMWcc_ARGS(X...) __RMWcc_ARGS(, ##X, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
-
-#define __RMWcc_CONCAT(a, b) a ## b
-#define RMWcc_CONCAT(a, b) __RMWcc_CONCAT(a, b)
+#include <linux/args.h>
#define __CLOBBERS_MEM(clb...) "memory", ## clb
@@ -48,7 +43,7 @@ cc_label: c = true; \
#define GEN_UNARY_RMWcc_3(op, var, cc) \
GEN_UNARY_RMWcc_4(op, var, cc, "%[var]")
-#define GEN_UNARY_RMWcc(X...) RMWcc_CONCAT(GEN_UNARY_RMWcc_, RMWcc_ARGS(X))(X)
+#define GEN_UNARY_RMWcc(X...) CONCATENATE(GEN_UNARY_RMWcc_, COUNT_ARGS(X))(X)
#define GEN_BINARY_RMWcc_6(op, var, cc, vcon, _val, arg0) \
__GEN_RMWcc(op " %[val], " arg0, var, cc, \
@@ -57,7 +52,7 @@ cc_label: c = true; \
#define GEN_BINARY_RMWcc_5(op, var, cc, vcon, val) \
GEN_BINARY_RMWcc_6(op, var, cc, vcon, val, "%[var]")
-#define GEN_BINARY_RMWcc(X...) RMWcc_CONCAT(GEN_BINARY_RMWcc_, RMWcc_ARGS(X))(X)
+#define GEN_BINARY_RMWcc(X...) CONCATENATE(GEN_BINARY_RMWcc_, COUNT_ARGS(X))(X)
#define GEN_UNARY_SUFFIXED_RMWcc(op, suffix, var, cc, clobbers...) \
__GEN_RMWcc(op " %[var]\n\t" suffix, var, cc, \
--- a/include/kunit/test.h~kernelh-split-out-count_args-and-concatenate-to-argsh
+++ a/include/kunit/test.h
@@ -12,6 +12,7 @@
#include <kunit/assert.h>
#include <kunit/try-catch.h>
+#include <linux/args.h>
#include <linux/compiler.h>
#include <linux/container_of.h>
#include <linux/err.h>
--- /dev/null
+++ a/include/linux/args.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _LINUX_ARGS_H
+#define _LINUX_ARGS_H
+
+/*
+ * How do these macros work?
+ *
+ * In __COUNT_ARGS() _0 to _12 are just placeholders from the start
+ * in order to make sure _n is positioned over the correct number
+ * from 12 to 0 (depending on X, which is a variadic argument list).
+ * They serve no purpose other than occupying a position. Since each
+ * macro parameter must have a distinct identifier, those identifiers
+ * are as good as any.
+ *
+ * In COUNT_ARGS() we use actual integers, so __COUNT_ARGS() returns
+ * that as _n.
+ */
+
+/* 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)
+
+/* Concatenate two parameters, but allow them to be expanded beforehand. */
+#define __CONCAT(a, b) a ## b
+#define CONCATENATE(a, b) __CONCAT(a, b)
+
+#endif /* _LINUX_ARGS_H */
--- a/include/linux/arm-smccc.h~kernelh-split-out-count_args-and-concatenate-to-argsh
+++ a/include/linux/arm-smccc.h
@@ -5,6 +5,7 @@
#ifndef __LINUX_ARM_SMCCC_H
#define __LINUX_ARM_SMCCC_H
+#include <linux/args.h>
#include <linux/init.h>
#include <uapi/linux/const.h>
@@ -413,11 +414,6 @@ asmlinkage void __arm_smccc_hvc(unsigned
#endif
-#define ___count_args(_0, _1, _2, _3, _4, _5, _6, _7, _8, x, ...) x
-
-#define __count_args(...) \
- ___count_args(__VA_ARGS__, 7, 6, 5, 4, 3, 2, 1, 0)
-
#define __constraint_read_0 "r" (arg0)
#define __constraint_read_1 __constraint_read_0, "r" (arg1)
#define __constraint_read_2 __constraint_read_1, "r" (arg2)
@@ -475,14 +471,6 @@ asmlinkage void __arm_smccc_hvc(unsigned
__declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res); \
register typeof(a7) arg7 asm("r7") = __a7
-#define ___declare_args(count, ...) __declare_arg_ ## count(__VA_ARGS__)
-#define __declare_args(count, ...) ___declare_args(count, __VA_ARGS__)
-
-#define ___constraints(count) \
- : __constraint_read_ ## count \
- : smccc_sve_clobbers "memory"
-#define __constraints(count) ___constraints(count)
-
/*
* We have an output list that is not necessarily used, and GCC feels
* entitled to optimise the whole sequence away. "volatile" is what
@@ -494,11 +482,13 @@ asmlinkage void __arm_smccc_hvc(unsigned
register unsigned long r1 asm("r1"); \
register unsigned long r2 asm("r2"); \
register unsigned long r3 asm("r3"); \
- __declare_args(__count_args(__VA_ARGS__), __VA_ARGS__); \
+ CONCATENATE(__declare_arg_, COUNT_ARGS(__VA_ARGS__)); \
asm volatile(SMCCC_SVE_CHECK \
inst "\n" : \
"=r" (r0), "=r" (r1), "=r" (r2), "=r" (r3) \
- __constraints(__count_args(__VA_ARGS__))); \
+ : CONCATENATE(__constraint_read_, \
+ COUNT_ARGS(__VA_ARGS__)) \
+ : smccc_sve_clobbers "memory"); \
if (___res) \
*___res = (typeof(*___res)){r0, r1, r2, r3}; \
} while (0)
@@ -542,8 +532,11 @@ asmlinkage void __arm_smccc_hvc(unsigned
*/
#define __fail_smccc_1_1(...) \
do { \
- __declare_args(__count_args(__VA_ARGS__), __VA_ARGS__); \
- asm ("" : __constraints(__count_args(__VA_ARGS__))); \
+ CONCATENATE(__declare_arg_, COUNT_ARGS(__VA_ARGS__)); \
+ asm ("" : \
+ : CONCATENATE(__constraint_read_, \
+ COUNT_ARGS(__VA_ARGS__)) \
+ : smccc_sve_clobbers "memory"); \
if (___res) \
___res->a0 = SMCCC_RET_NOT_SUPPORTED; \
} while (0)
--- a/include/linux/genl_magic_struct.h~kernelh-split-out-count_args-and-concatenate-to-argsh
+++ a/include/linux/genl_magic_struct.h
@@ -14,14 +14,12 @@
# error "you need to define GENL_MAGIC_INCLUDE_FILE before inclusion"
#endif
+#include <linux/args.h>
#include <linux/genetlink.h>
#include <linux/types.h>
-#define CONCAT__(a,b) a ## b
-#define CONCAT_(a,b) CONCAT__(a,b)
-
-extern int CONCAT_(GENL_MAGIC_FAMILY, _genl_register)(void);
-extern void CONCAT_(GENL_MAGIC_FAMILY, _genl_unregister)(void);
+extern int CONCATENATE(GENL_MAGIC_FAMILY, _genl_register)(void);
+extern void CONCATENATE(GENL_MAGIC_FAMILY, _genl_unregister)(void);
/*
* Extension of genl attribute validation policies {{{2
--- a/include/linux/kernel.h~kernelh-split-out-count_args-and-concatenate-to-argsh
+++ a/include/linux/kernel.h
@@ -457,13 +457,6 @@ ftrace_vprintk(const char *fmt, va_list
static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
#endif /* CONFIG_TRACING */
-/* 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)
-
-#define __CONCAT(a, b) a ## b
-#define CONCATENATE(a, b) __CONCAT(a, b)
-
/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
--- a/include/linux/pci.h~kernelh-split-out-count_args-and-concatenate-to-argsh
+++ a/include/linux/pci.h
@@ -23,7 +23,7 @@
#ifndef LINUX_PCI_H
#define LINUX_PCI_H
-
+#include <linux/args.h>
#include <linux/mod_devicetable.h>
#include <linux/types.h>
--- a/include/trace/bpf_probe.h~kernelh-split-out-count_args-and-concatenate-to-argsh
+++ a/include/trace/bpf_probe.h
@@ -12,6 +12,8 @@
#undef __perf_task
#define __perf_task(t) (t)
+#include <linux/args.h>
+
/* cast any integer, pointer, or small struct to u64 */
#define UINTTYPE(size) \
__typeof__(__builtin_choose_expr(size == 1, (u8)1, \
_
Patches currently in -mm which might be from andriy.shevchenko@xxxxxxxxxxxxxxx are
kernelh-split-out-count_args-and-concatenate-to-argsh.patch
