Merge remote-tracking branch 'sstabellini/for_1.1.1' into staging

* sstabellini/for_1.1.1:
  qemu/xendisk: set maximum number of grants to be used
This commit is contained in:
Anthony Liguori 2012-06-11 12:15:51 -05:00
commit 248bfdc9f5
1 changed files with 14 additions and 0 deletions

View File

@ -537,6 +537,15 @@ static void blk_bh(void *opaque)
blk_handle_requests(blkdev);
}
/*
* We need to account for the grant allocations requiring contiguous
* chunks; the worst case number would be
* max_req * max_seg + (max_req - 1) * (max_seg - 1) + 1,
* but in order to keep things simple just use
* 2 * max_req * max_seg.
*/
#define MAX_GRANTS(max_req, max_seg) (2 * (max_req) * (max_seg))
static void blk_alloc(struct XenDevice *xendev)
{
struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
@ -548,6 +557,11 @@ static void blk_alloc(struct XenDevice *xendev)
if (xen_mode != XEN_EMULATE) {
batch_maps = 1;
}
if (xc_gnttab_set_max_grants(xendev->gnttabdev,
MAX_GRANTS(max_requests, BLKIF_MAX_SEGMENTS_PER_REQUEST)) < 0) {
xen_be_printf(xendev, 0, "xc_gnttab_set_max_grants failed: %s\n",
strerror(errno));
}
}
static int blk_init(struct XenDevice *xendev)