| Message ID | 1351682381-8793-1-git-send-email-owasserm@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 10/31/2012 01:19 PM, Orit Wasserman wrote: > The number of bits is off by one, for example if last_ram_offset > is 0x1000 (the guest has one page) we get 0 bits instead of 1. > > Signed-off-by: Orit Wasserman <owasserm@redhat.com> > --- > arch_init.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch_init.c b/arch_init.c > index b75a4c5..a80c3c8 100644 > --- a/arch_init.c > +++ b/arch_init.c > @@ -565,7 +565,7 @@ static void reset_ram_globals(void) > static int ram_save_setup(QEMUFile *f, void *opaque) > { > RAMBlock *block; > - int64_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS; > + int64_t ram_pages = (last_ram_offset() >> TARGET_PAGE_BITS) + 1; > The original code calculates 1 for your example case.
On 31 October 2012 12:19, Orit Wasserman <owasserm@redhat.com> wrote: > The number of bits is off by one, for example if last_ram_offset > is 0x1000 (the guest has one page) we get 0 bits instead of 1. > > Signed-off-by: Orit Wasserman <owasserm@redhat.com> > --- > arch_init.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch_init.c b/arch_init.c > index b75a4c5..a80c3c8 100644 > --- a/arch_init.c > +++ b/arch_init.c > @@ -565,7 +565,7 @@ static void reset_ram_globals(void) > static int ram_save_setup(QEMUFile *f, void *opaque) > { > RAMBlock *block; > - int64_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS; > + int64_t ram_pages = (last_ram_offset() >> TARGET_PAGE_BITS) + 1; This will give you an extra bit if the last_ram_offset() is an exact multiple of the page size, though. Try int64_t ram_pages = DIV_ROUND_UP(last_ram_offset(), TARGET_PAGE_SIZE); ? -- PMM
On 10/31/2012 01:24 PM, Avi Kivity wrote: > On 10/31/2012 01:19 PM, Orit Wasserman wrote: >> The number of bits is off by one, for example if last_ram_offset >> is 0x1000 (the guest has one page) we get 0 bits instead of 1. >> >> Signed-off-by: Orit Wasserman <owasserm@redhat.com> >> --- >> arch_init.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch_init.c b/arch_init.c >> index b75a4c5..a80c3c8 100644 >> --- a/arch_init.c >> +++ b/arch_init.c >> @@ -565,7 +565,7 @@ static void reset_ram_globals(void) >> static int ram_save_setup(QEMUFile *f, void *opaque) >> { >> RAMBlock *block; >> - int64_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS; >> + int64_t ram_pages = (last_ram_offset() >> TARGET_PAGE_BITS) + 1; >> > > The original code calculates 1 for your example case. You correct ... sorry ... > >
On 10/31/2012 01:25 PM, Peter Maydell wrote: > On 31 October 2012 12:19, Orit Wasserman <owasserm@redhat.com> wrote: >> The number of bits is off by one, for example if last_ram_offset >> is 0x1000 (the guest has one page) we get 0 bits instead of 1. >> >> Signed-off-by: Orit Wasserman <owasserm@redhat.com> >> --- >> arch_init.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch_init.c b/arch_init.c >> index b75a4c5..a80c3c8 100644 >> --- a/arch_init.c >> +++ b/arch_init.c >> @@ -565,7 +565,7 @@ static void reset_ram_globals(void) >> static int ram_save_setup(QEMUFile *f, void *opaque) >> { >> RAMBlock *block; >> - int64_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS; >> + int64_t ram_pages = (last_ram_offset() >> TARGET_PAGE_BITS) + 1; > > This will give you an extra bit if the last_ram_offset() > is an exact multiple of the page size, though. Try > int64_t ram_pages = DIV_ROUND_UP(last_ram_offset(), TARGET_PAGE_SIZE); Good idea ... > ? > > -- PMM >
diff --git a/arch_init.c b/arch_init.c index b75a4c5..a80c3c8 100644 --- a/arch_init.c +++ b/arch_init.c @@ -565,7 +565,7 @@ static void reset_ram_globals(void) static int ram_save_setup(QEMUFile *f, void *opaque) { RAMBlock *block; - int64_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS; + int64_t ram_pages = (last_ram_offset() >> TARGET_PAGE_BITS) + 1; migration_bitmap = bitmap_new(ram_pages); bitmap_set(migration_bitmap, 0, ram_pages);
The number of bits is off by one, for example if last_ram_offset is 0x1000 (the guest has one page) we get 0 bits instead of 1. Signed-off-by: Orit Wasserman <owasserm@redhat.com> --- arch_init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)