Commit 8874a414 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Borislav Petkov (AMD)
Browse files

x86/qspinlock-paravirt: Fix missing-prototype warning 



__pv_queued_spin_unlock_slowpath() is defined in a header file as
a global function, and designed to be called from inline asm, but
there is no prototype visible in the definition:

  kernel/locking/qspinlock_paravirt.h:493:1: error: no previous \
    prototype for '__pv_queued_spin_unlock_slowpath' [-Werror=missing-prototypes]

Add this to the x86 header that contains the inline asm calling it,
and ensure this gets included before the definition, rather than
after it.

Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230803082619.1369127-8-arnd@kernel.org
parent ce0a1b60

arch/x86/include/asm/qspinlock_paravirt.h

+2 −0
Original line number Diff line number Diff line
@@ -4,6 +4,8 @@ 


#include <asm/ibt.h>



void __lockfunc __pv_queued_spin_unlock_slowpath(struct qspinlock *lock, u8 locked);



/*

 * For x86-64, PV_CALLEE_SAVE_REGS_THUNK() saves and restores 8 64-bit

 * registers. For i386, however, only 1 32-bit register needs to be saved

kernel/locking/qspinlock_paravirt.h

+10 −10
Original line number Diff line number Diff line
@@ -485,6 +485,16 @@ pv_wait_head_or_lock(struct qspinlock *lock, struct mcs_spinlock *node) 
	return (u32)(atomic_read(&lock->val) | _Q_LOCKED_VAL);

}



/*

 * Include the architecture specific callee-save thunk of the

 * __pv_queued_spin_unlock(). This thunk is put together with

 * __pv_queued_spin_unlock() to make the callee-save thunk and the real unlock

 * function close to each other sharing consecutive instruction cachelines.

 * Alternatively, architecture specific version of __pv_queued_spin_unlock()

 * can be defined.

 */

#include <asm/qspinlock_paravirt.h>



/*

 * PV versions of the unlock fastpath and slowpath functions to be used

 * instead of queued_spin_unlock().
@@ -533,16 +543,6 @@ __pv_queued_spin_unlock_slowpath(struct qspinlock *lock, u8 locked) 
	pv_kick(node->cpu);

}



/*

 * Include the architecture specific callee-save thunk of the

 * __pv_queued_spin_unlock(). This thunk is put together with

 * __pv_queued_spin_unlock() to make the callee-save thunk and the real unlock

 * function close to each other sharing consecutive instruction cachelines.

 * Alternatively, architecture specific version of __pv_queued_spin_unlock()

 * can be defined.

 */

#include <asm/qspinlock_paravirt.h>



#ifndef __pv_queued_spin_unlock

__visible __lockfunc void __pv_queued_spin_unlock(struct qspinlock *lock)

{