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powerpc: Make rwlocks endian safe 

Our ppc64 spinlocks and rwlocks use a trick where a lock token and
the paca index are placed in the lock with a single store. Since we
are using two u16s they need adjusting for little endian.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Anton Blanchard 2013-08-07 02:01:51 +10:00 committed by Benjamin Herrenschmidt
parent 8bd0b119ae
commit 54bb7f4bda
4 changed files with 21 additions and 0 deletions
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5
arch/powerpc/include/asm/paca.h
View File

@ -68,8 +68,13 @@ struct paca_struct {
* instruction. They must travel together and be properly
* aligned.
*/
#ifdef __BIG_ENDIAN__
u16 lock_token; /* Constant 0x8000, used in locks */
u16 paca_index; /* Logical processor number */
#else
u16 paca_index; /* Logical processor number */
u16 lock_token; /* Constant 0x8000, used in locks */
#endif
u64 kernel_toc; /* Kernel TOC address */
u64 kernelbase; /* Base address of kernel */

4
arch/powerpc/include/asm/spinlock.h
View File

@ -32,8 +32,12 @@
#ifdef CONFIG_PPC64
/* use 0x800000yy when locked, where yy == CPU number */
#ifdef __BIG_ENDIAN__
#define LOCK_TOKEN (*(u32 *)(&get_paca()->lock_token))
#else
#define LOCK_TOKEN (*(u32 *)(&get_paca()->paca_index))
#endif
#else
#define LOCK_TOKEN 1
#endif

4
arch/powerpc/kvm/book3s_hv_rm_mmu.c
View File

@ -363,7 +363,11 @@ long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
vcpu->arch.pgdir, true, &vcpu->arch.gpr[4]);
}
#ifdef __BIG_ENDIAN__
#define LOCK_TOKEN (*(u32 *)(&get_paca()->lock_token))
#else
#define LOCK_TOKEN (*(u32 *)(&get_paca()->paca_index))
#endif
static inline int try_lock_tlbie(unsigned int *lock)
{

8
arch/powerpc/kvm/book3s_hv_rmhandlers.S
View File

@ -393,7 +393,11 @@ toc_tlbie_lock:
.tc native_tlbie_lock[TC],native_tlbie_lock
.previous
ld r3,toc_tlbie_lock@toc(2)
#ifdef __BIG_ENDIAN__
lwz r8,PACA_LOCK_TOKEN(r13)
#else
lwz r8,PACAPACAINDEX(r13)
#endif
24: lwarx r0,0,r3
cmpwi r0,0
bne 24b
@ -968,7 +972,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
32: ld r4,VCPU_KVM(r9) /* pointer to struct kvm */
/* Take the guest's tlbie_lock */
#ifdef __BIG_ENDIAN__
lwz r8,PACA_LOCK_TOKEN(r13)
#else
lwz r8,PACAPACAINDEX(r13)
#endif
addi r3,r4,KVM_TLBIE_LOCK
24: lwarx r0,0,r3
cmpwi r0,0