KVM: PPC: Revert "KVM: PPC: Use kernel hash function"
It turns out the in-kernel hash function is sub-optimal for our subtle hash inputs where every bit is significant. So let's revert to the original hash functions. This reverts commit 05340ab4f9a6626f7a2e8f9fe5397c61d494f445. Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
Родитель
928d78be54
Коммит
b9877ce299
|
@ -19,7 +19,6 @@
|
|||
*/
|
||||
|
||||
#include <linux/kvm_host.h>
|
||||
#include <linux/hash.h>
|
||||
|
||||
#include <asm/kvm_ppc.h>
|
||||
#include <asm/kvm_book3s.h>
|
||||
|
@ -77,7 +76,14 @@ void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte)
|
|||
* a hash, so we don't waste cycles on looping */
|
||||
static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid)
|
||||
{
|
||||
return hash_64(gvsid, SID_MAP_BITS);
|
||||
return (u16)(((gvsid >> (SID_MAP_BITS * 7)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 6)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 5)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 4)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 3)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 2)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 1)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 0)) & SID_MAP_MASK));
|
||||
}
|
||||
|
||||
|
||||
|
|
|
@ -20,7 +20,6 @@
|
|||
*/
|
||||
|
||||
#include <linux/kvm_host.h>
|
||||
#include <linux/hash.h>
|
||||
|
||||
#include <asm/kvm_ppc.h>
|
||||
#include <asm/kvm_book3s.h>
|
||||
|
@ -44,9 +43,17 @@ void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte)
|
|||
* a hash, so we don't waste cycles on looping */
|
||||
static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid)
|
||||
{
|
||||
return hash_64(gvsid, SID_MAP_BITS);
|
||||
return (u16)(((gvsid >> (SID_MAP_BITS * 7)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 6)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 5)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 4)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 3)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 2)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 1)) & SID_MAP_MASK) ^
|
||||
((gvsid >> (SID_MAP_BITS * 0)) & SID_MAP_MASK));
|
||||
}
|
||||
|
||||
|
||||
static struct kvmppc_sid_map *find_sid_vsid(struct kvm_vcpu *vcpu, u64 gvsid)
|
||||
{
|
||||
struct kvmppc_sid_map *map;
|
||||
|
|
Загрузка…
Ссылка в новой задаче