linux-stable/kernel/dma
Barry Song 65789daa80 dma-mapping: add benchmark support for streaming DMA APIs
Nowadays, there are increasing requirements to benchmark the performance
of dma_map and dma_unmap particually while the device is attached to an
IOMMU.

This patch enables the support. Users can run specified number of threads
to do dma_map_page and dma_unmap_page on a specific NUMA node with the
specified duration. Then dma_map_benchmark will calculate the average
latency for map and unmap.

A difficulity for this benchmark is that dma_map/unmap APIs must run on
a particular device. Each device might have different backend of IOMMU or
non-IOMMU.

So we use the driver_override to bind dma_map_benchmark to a particual
device by:
For platform devices:
echo dma_map_benchmark > /sys/bus/platform/devices/xxx/driver_override
echo xxx > /sys/bus/platform/drivers/xxx/unbind
echo xxx > /sys/bus/platform/drivers/dma_map_benchmark/bind

For PCI devices:
echo dma_map_benchmark > /sys/bus/pci/devices/0000:00:01.0/driver_override
echo 0000:00:01.0 > /sys/bus/pci/drivers/xxx/unbind
echo 0000:00:01.0 > /sys/bus/pci/drivers/dma_map_benchmark/bind

Cc: Will Deacon <will@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
[hch: folded in two fixes from Colin Ian King <colin.king@canonical.com>]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-11-27 10:33:42 +01:00
..
coherent.c dma-mapping: split <linux/dma-mapping.h> 2020-10-06 07:07:03 +02:00
contiguous.c dma-contiguous: fix a typo error in a comment 2020-11-27 10:33:42 +01:00
debug.c dma-mapping: move dma-debug.h to kernel/dma/ 2020-10-06 07:07:05 +02:00
debug.h dma-mapping: move dma-debug.h to kernel/dma/ 2020-10-06 07:07:05 +02:00
direct.c kernel/: fix repeated words in comments 2020-10-16 11:11:19 -07:00
direct.h dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma 2020-10-06 07:07:06 +02:00
dummy.c dma-mapping: split <linux/dma-mapping.h> 2020-10-06 07:07:03 +02:00
Kconfig dma-mapping: add benchmark support for streaming DMA APIs 2020-11-27 10:33:42 +01:00
Makefile dma-mapping: add benchmark support for streaming DMA APIs 2020-11-27 10:33:42 +01:00
map_benchmark.c dma-mapping: add benchmark support for streaming DMA APIs 2020-11-27 10:33:42 +01:00
mapping.c dma-mapping: Allow mixing bypass and mapped DMA operation 2020-11-27 10:33:40 +01:00
ops_helpers.c dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h> 2020-10-06 07:07:06 +02:00
pool.c dma-pool: no need to check return value of debugfs_create functions 2020-11-27 10:33:42 +01:00
remap.c dma-mapping: move more functions to dma-map-ops.h 2020-10-20 10:41:07 +02:00
swiotlb.c swiotlb: remove the tbl_dma_addr argument to swiotlb_tbl_map_single 2020-11-02 10:10:39 -05:00
virt.c dma-mapping: split <linux/dma-mapping.h> 2020-10-06 07:07:03 +02:00