From 595cb754983d4387cb25b3dcf08f5129663d634e Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Tue, 17 Sep 2013 09:30:34 +0300 Subject: [PATCH] vhost/scsi: use vmalloc for order-10 allocation As vhost scsi device struct is large, if the device is created on a busy system, kzalloc() might fail, so this patch does a fallback to vzalloc(). As vmalloc() adds overhead on data-path, add __GFP_REPEAT to kzalloc() flags to do this fallback only when really needed. Reviewed-by: Asias He Reported-by: Dan Aloni Signed-off-by: Michael S. Tsirkin --- drivers/vhost/scsi.c | 41 +++++++++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 14 deletions(-) diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c index 4b79a1f..38ccf4a 100644 --- a/drivers/vhost/scsi.c +++ b/drivers/vhost/scsi.c @@ -1373,21 +1373,30 @@ static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features) return 0; } +static void vhost_scsi_free(struct vhost_scsi *vs) +{ + if (is_vmalloc_addr(vs)) + vfree(vs); + else + kfree(vs); +} + static int vhost_scsi_open(struct inode *inode, struct file *f) { struct vhost_scsi *vs; struct vhost_virtqueue **vqs; - int r, i; + int r = -ENOMEM, i; - vs = kzalloc(sizeof(*vs), GFP_KERNEL); - if (!vs) - return -ENOMEM; + vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); + if (!vs) { + vs = vzalloc(sizeof(*vs)); + if (!vs) + goto err_vs; + } vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL); - if (!vqs) { - kfree(vs); - return -ENOMEM; - } + if (!vqs) + goto err_vqs; vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work); vhost_work_init(&vs->vs_event_work, tcm_vhost_evt_work); @@ -1407,14 +1416,18 @@ static int vhost_scsi_open(struct inode *inode, struct file *f) tcm_vhost_init_inflight(vs, NULL); - if (r < 0) { - kfree(vqs); - kfree(vs); - return r; - } + if (r < 0) + goto err_init; f->private_data = vs; return 0; + +err_init: + kfree(vqs); +err_vqs: + vhost_scsi_free(vs); +err_vs: + return r; } static int vhost_scsi_release(struct inode *inode, struct file *f) @@ -1431,7 +1444,7 @@ static int vhost_scsi_release(struct inode *inode, struct file *f) /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */ vhost_scsi_flush(vs); kfree(vs->dev.vqs); - kfree(vs); + vhost_scsi_free(vs); return 0; } -- 2.7.4