[SeaBIOS] [PATCH 3/3] ahci: alloc structs in high memory, simplify realloc
kevin at koconnor.net
Wed Nov 27 04:08:01 CET 2013
On Tue, Nov 26, 2013 at 02:23:41PM +0100, Gerd Hoffmann wrote:
> With ahci running in 32bit mode we can also allocate the
> (ahci private) data structures in high memory. This
> reduces the real mode memory footprint and also simplifies
> the realloc as we only need to move struct ahci_port_s
> (which contains struct drive_s) from high memory to fseg
> in case the port probe was successful.
> Signed-off-by: Gerd Hoffmann <kraxel at redhat.com>
> src/hw/ahci.c | 27 ++++-----------------------
> 1 file changed, 4 insertions(+), 23 deletions(-)
> diff --git a/src/hw/ahci.c b/src/hw/ahci.c
> index 5984c1c..5add207 100644
> --- a/src/hw/ahci.c
> +++ b/src/hw/ahci.c
> @@ -358,9 +358,9 @@ ahci_port_alloc(struct ahci_ctrl_s *ctrl, u32 pnr)
> port->pnr = pnr;
> port->ctrl = ctrl;
> - port->list = memalign_tmp(1024, 1024);
> - port->fis = memalign_tmp(256, 256);
> - port->cmd = memalign_tmp(256, 256);
> + port->list = memalign_high(1024, 1024);
> + port->fis = memalign_high(256, 256);
> + port->cmd = memalign_high(256, 256);
Ideally, one wouldn't allocate in "high" ram and then go on to free
it. (Memory fragmentation due to malloc/free could chew up some guest
ram.) So, I'm not sure this is an improvement.
Also, if this is done then it wont work for 1Meg guests. That's
probably not a concern though.
Otherwise, the other patches look fine to me.
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