Message ID | 20210805152804.100333-9-david@redhat.com |
---|---|
State | New |
Headers | show |
Series | s390x: skey related fixes, cleanups, and memory device preparations | expand |
On 05/08/2021 17.28, David Hildenbrand wrote: > Avoid setting the key if nothing changed. > > Signed-off-by: David Hildenbrand <david@redhat.com> > --- > target/s390x/mmu_helper.c | 11 +++++++---- > 1 file changed, 7 insertions(+), 4 deletions(-) > > diff --git a/target/s390x/mmu_helper.c b/target/s390x/mmu_helper.c > index 36ab4e9c81..0c2c39a970 100644 > --- a/target/s390x/mmu_helper.c > +++ b/target/s390x/mmu_helper.c > @@ -301,7 +301,7 @@ static void mmu_handle_skey(target_ulong addr, int rw, int *flags) > { > static S390SKeysClass *skeyclass; > static S390SKeysState *ss; > - uint8_t key; > + uint8_t key, old_key; > int rc; > > /* > @@ -337,6 +337,7 @@ static void mmu_handle_skey(target_ulong addr, int rw, int *flags) > trace_get_skeys_nonzero(rc); > return; > } > + old_key = key; > > switch (rw) { > case MMU_DATA_LOAD: > @@ -360,9 +361,11 @@ static void mmu_handle_skey(target_ulong addr, int rw, int *flags) > /* Any store/fetch sets the reference bit */ > key |= SK_R; > > - rc = skeyclass->set_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key); > - if (rc) { > - trace_set_skeys_nonzero(rc); > + if (key != old_key) { > + rc = skeyclass->set_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key); > + if (rc) { > + trace_set_skeys_nonzero(rc); > + } > } > } > > Reviewed-by: Thomas Huth <thuth@redhat.com>
diff --git a/target/s390x/mmu_helper.c b/target/s390x/mmu_helper.c index 36ab4e9c81..0c2c39a970 100644 --- a/target/s390x/mmu_helper.c +++ b/target/s390x/mmu_helper.c @@ -301,7 +301,7 @@ static void mmu_handle_skey(target_ulong addr, int rw, int *flags) { static S390SKeysClass *skeyclass; static S390SKeysState *ss; - uint8_t key; + uint8_t key, old_key; int rc; /* @@ -337,6 +337,7 @@ static void mmu_handle_skey(target_ulong addr, int rw, int *flags) trace_get_skeys_nonzero(rc); return; } + old_key = key; switch (rw) { case MMU_DATA_LOAD: @@ -360,9 +361,11 @@ static void mmu_handle_skey(target_ulong addr, int rw, int *flags) /* Any store/fetch sets the reference bit */ key |= SK_R; - rc = skeyclass->set_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key); - if (rc) { - trace_set_skeys_nonzero(rc); + if (key != old_key) { + rc = skeyclass->set_skeys(ss, addr / TARGET_PAGE_SIZE, 1, &key); + if (rc) { + trace_set_skeys_nonzero(rc); + } } }
Avoid setting the key if nothing changed. Signed-off-by: David Hildenbrand <david@redhat.com> --- target/s390x/mmu_helper.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)