From 4aae977721f0367809cdc94584b6945073d9fe10 Mon Sep 17 00:00:00 2001 From: Logan Gunthorpe Date: Fri, 3 Jun 2016 14:50:31 -0600 Subject: [PATCH] ntb_perf: Allow limiting the size of the memory windows On my system, dma_alloc_coherent won't produce memory anywhere near the size of the BAR. So I needed a way to limit this. It's pretty much copied straight from ntb_transport. Signed-off-by: Logan Gunthorpe Acked-by: Dave Jiang Signed-off-by: Jon Mason --- drivers/ntb/test/ntb_perf.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/ntb/test/ntb_perf.c b/drivers/ntb/test/ntb_perf.c index 8dfce9c..30635c8 100644 --- a/drivers/ntb/test/ntb_perf.c +++ b/drivers/ntb/test/ntb_perf.c @@ -83,6 +83,10 @@ MODULE_DESCRIPTION(DRIVER_DESCRIPTION); static struct dentry *perf_debugfs_dir; +static unsigned long max_mw_size; +module_param(max_mw_size, ulong, 0644); +MODULE_PARM_DESC(max_mw_size, "Limit size of large memory windows"); + static unsigned int seg_order = 19; /* 512K */ module_param(seg_order, uint, 0644); MODULE_PARM_DESC(seg_order, "size order [n^2] of buffer segment for testing"); @@ -472,6 +476,10 @@ static void perf_link_work(struct work_struct *work) dev_dbg(&perf->ntb->pdev->dev, "%s called\n", __func__); size = perf->mw.phys_size; + + if (max_mw_size && size > max_mw_size) + size = max_mw_size; + ntb_peer_spad_write(ndev, MW_SZ_HIGH, upper_32_bits(size)); ntb_peer_spad_write(ndev, MW_SZ_LOW, lower_32_bits(size)); ntb_peer_spad_write(ndev, VERSION, PERF_VERSION); -- 2.7.4