[PATCH] x86: vsmp: avoid link error with gcc -Og

From: Arnd Bergmann <arnd@arndb.de>
To: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	x86@kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>, "H. Peter Anvin" <hpa@zytor.com>,
	Juergen Gross <jgross@suse.com>,
	linux-kernel@vger.kernel.org
Subject: [PATCH] x86: vsmp: avoid link error with gcc -Og
Date: Fri,  2 Nov 2018 16:49:22 +0100	[thread overview]
Message-ID: <20181102154935.2073592-1-arnd@arndb.de> (raw)

When the compiler skips optimizations for ease of debugging,
teh vsmp_cap_cpus() function is not eliminated from the build
with CONFIG_PCI=n:

arch/x86/kernel/vsmp_64.o: In function `vsmp_cap_cpus':
vsmp_64.c:(.init.text+0x23): undefined reference to `read_pci_config'

Change the caller in a way that will always optimize this
as required.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 arch/x86/kernel/vsmp_64.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/vsmp_64.c b/arch/x86/kernel/vsmp_64.c
index 1eae5af491c2..6a2ae6964ce5 100644
--- a/arch/x86/kernel/vsmp_64.c
+++ b/arch/x86/kernel/vsmp_64.c
@@ -146,8 +146,10 @@ static void __init detect_vsmp_box(void)
 		is_vsmp = 1;
 }
 
-static int is_vsmp_box(void)
+static int __init is_vsmp_box(void)
 {
+	detect_vsmp_box();
+
 	if (is_vsmp != -1)
 		return is_vsmp;
 	else {
@@ -157,10 +159,7 @@ static int is_vsmp_box(void)
 }
 
 #else
-static void __init detect_vsmp_box(void)
-{
-}
-static int is_vsmp_box(void)
+static __always_inline int is_vsmp_box(void)
 {
 	return 0;
 }
@@ -213,7 +212,6 @@ static void vsmp_apic_post_init(void)
 
 void __init vsmp_init(void)
 {
-	detect_vsmp_box();
 	if (!is_vsmp_box())
 		return;
 
-- 
2.18.0

