From de90dfccbcb9c305a13a7ed1dcd77df2d1c16785 Mon Sep 17 00:00:00 2001
From: Carlo Caione <ccaione@baylibre.com>
Date: Thu, 20 Apr 2023 17:04:55 +0200
Subject: [PATCH] syscall: Introduce __syscall_always_inline

Sometimes we want to force the inlining of a __syscall. Introduce a new
__syscall_always_inline symbol to do that.

Signed-off-by: Carlo Caione <ccaione@baylibre.com>
---
 .clang-format                     |  1 +
 doc/conf.py                       |  1 +
 doc/zephyr.doxyfile.in            |  1 +
 include/zephyr/toolchain/common.h |  2 ++
 scripts/build/parse_syscalls.py   | 10 +++++-----
 5 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/.clang-format b/.clang-format
index e5f69355cbe..fdcd735fe28 100644
--- a/.clang-format
+++ b/.clang-format
@@ -24,6 +24,7 @@ AttributeMacros:
   - __packed
   - __printf_like
   - __syscall
+  - __syscall_always_inline
   - __subsystem
 BitFieldColonSpacing: After
 BreakBeforeBraces: Linux
diff --git a/doc/conf.py b/doc/conf.py
index aeccbd204b0..497373060aa 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -232,6 +232,7 @@ breathe_default_members = ("members", )
 
 cpp_id_attributes = [
     "__syscall",
+    "__syscall_always_inline",
     "__deprecated",
     "__may_alias",
     "__used",
diff --git a/doc/zephyr.doxyfile.in b/doc/zephyr.doxyfile.in
index 0a066ace08e..50fc3e75304 100644
--- a/doc/zephyr.doxyfile.in
+++ b/doc/zephyr.doxyfile.in
@@ -2397,6 +2397,7 @@ PREDEFINED             = __DOXYGEN__ \
                          "__printf_like(x, y)=" \
                          __attribute__(x)= \
                          __syscall= \
+                         __syscall_always_inline= \
                          __must_check= \
                          "ATOMIC_DEFINE(x, y)=atomic_t x[ATOMIC_BITMAP_SIZE(y)]"
 
diff --git a/include/zephyr/toolchain/common.h b/include/zephyr/toolchain/common.h
index 9259dc438ad..4f8708c427c 100644
--- a/include/zephyr/toolchain/common.h
+++ b/include/zephyr/toolchain/common.h
@@ -143,8 +143,10 @@
  */
 #ifndef ZTEST_UNITTEST
 #define __syscall static inline
+#define __syscall_always_inline static inline __attribute__((always_inline))
 #else
 #define __syscall
+#define __syscall_always_inline
 #endif /* ZTEST_UNITTEST */
 
 /* Definitions for struct declaration tags. These are sentinel values used by
diff --git a/scripts/build/parse_syscalls.py b/scripts/build/parse_syscalls.py
index 4385f5a8a9a..3536d52a9c4 100644
--- a/scripts/build/parse_syscalls.py
+++ b/scripts/build/parse_syscalls.py
@@ -33,11 +33,11 @@ import json
 regex_flags = re.MULTILINE | re.VERBOSE
 
 syscall_regex = re.compile(r'''
-__syscall\s+                    # __syscall attribute, must be first
-([^(]+)                         # type and name of system call (split later)
-[(]                             # Function opening parenthesis
-([^)]*)                         # Arg list (split later)
-[)]                             # Closing parenthesis
+(?:__syscall|__syscall_always_inline)\s+   # __syscall attribute, must be first
+([^(]+)                                    # type and name of system call (split later)
+[(]                                        # Function opening parenthesis
+([^)]*)                                    # Arg list (split later)
+[)]                                        # Closing parenthesis
 ''', regex_flags)
 
 struct_tags = ["__subsystem", "__net_socket"]