From 2a87151fb2725658f7419038a80f91065159f34b Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Mon, 7 Jul 2014 15:15:53 +0200 Subject: block: bump coroutine pool size for drives When a BlockDriverState is associated with a storage controller DeviceState we expect guest I/O. Use this opportunity to bump the coroutine pool size by 64. This patch ensures that the coroutine pool size scales with the number of drives attached to the guest. It should increase coroutine pool usage (which makes qemu_coroutine_create() fast) without hogging too much memory when fewer drives are attached. Signed-off-by: Stefan Hajnoczi Reviewed-by: Eric Blake --- block.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'block.c') diff --git a/block.c b/block.c index 7cafc49..6b29285 100644 --- a/block.c +++ b/block.c @@ -57,6 +57,8 @@ struct BdrvDirtyBitmap { #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ +#define COROUTINE_POOL_RESERVATION 64 /* number of coroutines to reserve */ + static void bdrv_dev_change_media_cb(BlockDriverState *bs, bool load); static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, @@ -2107,6 +2109,9 @@ int bdrv_attach_dev(BlockDriverState *bs, void *dev) } bs->dev = dev; bdrv_iostatus_reset(bs); + + /* We're expecting I/O from the device so bump up coroutine pool size */ + qemu_coroutine_adjust_pool_size(COROUTINE_POOL_RESERVATION); return 0; } @@ -2126,6 +2131,7 @@ void bdrv_detach_dev(BlockDriverState *bs, void *dev) bs->dev_ops = NULL; bs->dev_opaque = NULL; bs->guest_block_size = 512; + qemu_coroutine_adjust_pool_size(-COROUTINE_POOL_RESERVATION); } /* TODO change to return DeviceState * when all users are qdevified */ -- cgit v1.1