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2016-11-13ntb_perf: potential info leak in debugfsDan Carpenter1-3/+3
This is a static checker warning, not something I'm desperately concerned about. But snprintf() returns the number of bytes that would have been copied if there were space. We really care about the number of bytes that actually were copied so we should use scnprintf() instead. It probably won't overrun, and in that case we may as well just use sprintf() but these sorts of things make static checkers and code reviewers happier. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-11-13ntb: ntb_hw_intel: init peer_addr in struct intel_ntb_devDave Jiang1-0/+3
The peer_addr member of intel_ntb_dev is not set, therefore when acquiring ntb_peer_db and ntb_peer_spad we only get the offset rather than the actual physical address. Adding fix to correct that. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-11-13ntb: make DMA_OUT_RESOURCE_TO HZ independentNicholas Mc Guire1-1/+1
schedule_timeout_* takes a timeout in jiffies but the code currently is passing in a constant which makes this timeout HZ dependent, so pass it through msecs_to_jiffies() to fix this up. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-11-13ntb_transport: make DMA_OUT_RESOURCE_TO HZ independentNicholas Mc Guire1-1/+1
schedule_timeout_* takes a timeout in jiffies but the code currently is passing in a constant which makes this timeout HZ dependent, so pass it through msecs_to_jiffies() to fix this up. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-11-13NTB: ntb_hw_intel: Fix typo in module parameter descriptionsWei Yongjun1-6/+6
Fix typo in module parameter descriptions. Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-11-13ntb_pingpong: Fix db_init parameter descriptionWei Yongjun1-1/+1
Fix 'db_init' parameter description. Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-08ntb: add DMA error handling for RX DMADave Jiang1-16/+67
Adding support on the rx DMA path to allow recovery of errors when DMA responds with error status and abort all the subsequent ops. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Cc: Jon Mason <jdmason@kudzu.us> Cc: linux-ntb@googlegroups.com Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-08-08ntb: add DMA error handling for TX DMADave Jiang1-27/+83
Adding support on the tx DMA path to allow recovery of errors when DMA responds with error status and abort all the subsequent ops. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Cc: Jon Mason <jdmason@kudzu.us> Cc: linux-ntb@googlegroups.com Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-08-05NTB: ntb_hw_intel: use local variable pdevAllen Hubbe1-5/+5
Clean up duplicated expression by replacing it with the equivalent local variable pdev. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05NTB: ntb_hw_intel: show BAR size in debugfs infoAllen Hubbe1-1/+38
It will be useful to know the hardware configured BAR size to diagnose issues with NTB memory windows. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_perf: clear link_is_up flag when the link goes down.Logan Gunthorpe1-19/+9
When the link goes down, the link_is_up flag did not return to false. This could have caused some subtle corner case bugs when the link goes up and down quickly. Once that was fixed, there was found to be a race if the link was brought down then immediately up. The link_cleanup work would occasionally be scheduled after the next link up event. This would cancel the link_work that was supposed to occur and leave ntb_perf in an unusable state. To fix this we get rid of the link_cleanup work and put the actions directly in the link_down event. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_pingpong: Add a debugfs file to get the ping countLogan Gunthorpe1-1/+61
This commit adds a debugfs 'count' file to ntb_pingpong. This is so testing with ntb_pingpong can be automated beyond just checking the logs for pong messages. The count file returns a number which increments every pong. The counter can be cleared by writing a zero. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_tool: Add link status and files to debugfsLogan Gunthorpe1-0/+92
In order to more successfully script with ntb_tool it's useful to have a link file to check the link status so that the script doesn't use the other files until the link is up. This commit adds a 'link' file to the debugfs directory which reads boolean (Y or N) depending on the link status. Writing to the file change the link state using ntb_link_enable or ntb_link_disable. A 'link_event' file is also provided so an application can block until the link changes to the desired state. If the user writes a 1, it will block until the link is up. If the user writes a 0, it will block until the link is down. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_tool: Postpone memory window initialization for the userLogan Gunthorpe1-138/+228
In order to make the interface closer to the raw NTB API, this commit changes memory windows so they are not initialized on link up. Instead, the 'peer_trans*' debugfs files are introduced. When read, they return information provided by ntb_mw_get_range. When written, they create a buffer and initialize the memory window. The value written is taken as the requested size of the buffer (which is then rounded for alignment). Writing a value of zero frees the buffer and tears down the memory window translation. The 'peer_mw*' file is only created once the memory window translation is setup by the user. Additionally, it was noticed that the read and write functions for the 'peer_mw*' files should have checked for a NULL pointer. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_perf: Wait for link before running testLogan Gunthorpe1-1/+4
Instead of returning immediately with an error when the link is down, wait for the link to come up (or the user sends a SIGINT). This is to make scripting ntb_perf easier. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_perf: Return results by reading the run fileLogan Gunthorpe1-12/+55
Instead of having to watch logs, allow the results to be retrieved by reading back the run file. This file will return "running" when the test is running and nothing if no tests have been run yet. It returns 1 line per thread, and will display an error message if the corresponding thread returns an error. With the above change, the pr_info calls that returned the results are then changed to pr_debug calls. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_perf: Improve thread handling to increase robustnessLogan Gunthorpe1-48/+76
This commit accomplishes a few things: 1) Properly prevent multiple sets of threads from running at once using a mutex. Lots of race issues existed with the thread_cleanup. 2) The mutex allows us to ensure that threads are finished before tearing down the device or module. 3) Don't use kthread_stop when the threads can exit by themselves, as this is counter-indicated by the kthread_create documentation. Threads now wait for kthread_stop to occur. 4) Writing to the run file now blocks until the threads are complete. The test can then be safely interrupted by a SIGINT. Also, while I was at it: 5) debugfs_run_write shouldn't return 0 in the early check cases as this could cause debugfs_run_write to loop undesirably. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_perf: Schedule based on time not on performanceLogan Gunthorpe1-2/+4
When debugging performance problems, if some issue causes the ntb hardware to be significantly slower than expected, ntb_perf will hang requiring a reboot because it only schedules once every 4GB. Instead, schedule based on jiffies so it will not hang the CPU if the transfer is slow. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_transport: Check the number of spads the hardware supportsLogan Gunthorpe2-4/+13
I'm working on hardware that currently has a limited number of scratchpad registers and ntb_ndev fails with no clue as to why. I feel it is better to fail early and provide a reasonable error message then to fail later on. The same is done to ntb_perf, but it doesn't currently require enough spads to actually fail. I've also removed the unused SPAD_MSG and SPAD_ACK enums so that MAX_SPAD accurately reflects the number of spads used. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_tool: Add memory window debug supportLogan Gunthorpe1-1/+257
We allocate some memory window buffers when the link comes up, then we provide debugfs files to read/write each side of the link. This is useful for debugging the mapping when writing new drivers. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_perf: Allow limiting the size of the memory windowsLogan Gunthorpe1-0/+8
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 <logang@deltatee.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05NTB: allocate number transport entries depending on size of ring sizeDave Jiang1-2/+27
Currently we only allocate a fixed default number of descriptors for the tx and rx side. We should dynamically resize it to the number of descriptors resides in the transport rings. We should know the number of transmit descriptors at initializaiton. We will allocate the default number of descriptors for receive side and allocate additional ones when we know the actual max entries for receive. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Allen Hubbe <allen.hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_tool: BUG: Ensure the buffer size is large enough to return all spadsLogan Gunthorpe1-2/+8
On hardware with 32 scratchpad registers the spad field in ntb tool could chop off the end. The maximum buffer size is increased from 256 to 15 times the number or scratchpads. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05ntb_tool: Fix infinite loop bug when writing spad/peer_spad fileLogan Gunthorpe1-4/+5
If you tried to write two spads in one line, as per the example: root@peer# echo '0 0x01010101 1 0x7f7f7f7f' > $DBG_DIR/peer_spad then the CPU would freeze in an infinite loop. This wasn't immediately obvious but 'pos' was not incrementing the buffer, so after reading the second pair of values, 'pos' would once again be 3 and it would re-read the second pair of values ad infinitum. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-26NTB: Remove _addr functions from ntb_hw_amdAllen Hubbe1-30/+0
Kernel zero day testing warned about address space confusion. A virtual iomem address was used where a physical address is expected. The offending functions implement an optional part of the api, so they are removed. They can be added later, after testing. Fixes: a1b3695820aa490e58915d720a1438069813008b Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Acked-by: Xiangliang Yu <Xiangliang.Yu@amd.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-21NTB: Fix incorrect clean up routine in ntb_perfDave Jiang1-18/+24
The clean up routine when we failed to allocate kthread is not cleaning up all the threads, only the same one over and over again. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-21NTB: Fix incorrect return check in ntb_perfDave Jiang1-4/+3
kthread_create_no_node() returns error pointers, never NULL. Fix check so it handles error correctly. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-17ntb: fix possible NULL dereferenceSudip Mukherjee1-0/+2
kmalloc can fail and we should check for NULL before using the pointer returned by kmalloc. Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-17ntb: add missing setup of translation windowDave Jiang1-0/+8
The perf tool is missing the setup of translation window. Adding call to setup the translation window for backed memory. Signed-off-by: John Kading <john.kading@gd-ms.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-17ntb: stop link work when we do not have memoryDave Jiang1-1/+8
Instead of keep trying to go through the init routine when we aren't able to allocate memory, we should just stop and go down. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-17ntb: stop tasklet from spinning forever during shutdown.Dave Jiang1-6/+16
We can leave tasklet spinning forever if we disable the tasklet during qp shutdown and the tasklets are still being kicked off. This hopefully should avoid that race condition. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reported-by: Alex Depoutovitch <alex@pernixdata.com> Tested-by: Alex Depoutovitch <alex@pernixdata.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-17ntb: perf test: fix address space confusionArnd Bergmann1-10/+11
The ntb driver assigns between pointers an __iomem tokens, and also casts them to 64-bit integers, which results in compiler warnings on 32-bit systems: drivers/ntb/test/ntb_perf.c: In function 'perf_copy': drivers/ntb/test/ntb_perf.c:213:10: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast] vbase = (u64)(u64 *)mw->vbase; ^ drivers/ntb/test/ntb_perf.c:214:14: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast] dst_vaddr = (u64)(u64 *)dst; ^ This adds __iomem annotations where needed and changes the temporary variables to iomem pointers to avoid casting them to u64. I did not see the problem in linux-next earlier, but it show showed up in 4.5-rc1. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Dave Jiang <dave.jiang@intel.com> Fixes: 8a7b6a778a85 ("ntb: ntb perf tool") Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-01-21NTB: Fix macro parameter conflict with field nameAllen Hubbe1-2/+3
If the parameter given to the macro is replaced throughout the macro as it is evaluated. The intent is that the macro parameter should replace the only the first parameter to container_of(). However, the way the macro was written, it would also inadvertantly replace a structure field name. If a parameter of any other name is given to the macro, it will fail to compile, if the structure does not contain a field of the same name. At worst, it will compile, and hide improper access of an unintended field in the structure. Change the macro parameter name, so it does not conflict with the structure field name. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-01-21NTB: Add support for AMD PCI-Express Non-Transparent BridgeXiangliang Yu6-0/+1370
This adds support for AMD's PCI-Express Non-Transparent Bridge (NTB) device on the Zeppelin platform. The driver connnects to the standard NTB sub-system interface, with modification to add hooks for power management in a separate patch. The AMD NTB device has 3 memory windows, 16 doorbell, 16 scratch-pad registers, and supports up to 16 PCIe lanes running a Gen3 speeds. Signed-off-by: Xiangliang Yu <Xiangliang.Yu@amd.com> Reviewed-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-01-17ntb: ntb perf toolDave Jiang3-0/+757
Providing raw performance data via a tool that directly access data from NTB w/o any software overhead. This allows measurement of the hardware performance limit. In revision one we are only doing single direction CPU and DMA writes. Eventually we will provide bi-directional writes. The measurement using DMA engine for NTB performance measure does not measure the raw performance of DMA engine over NTB due to software overhead. But it should provide the peak performance through the Linux DMA driver. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Tested-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-01-11NTB: Address out of DMA descriptor issue with NTBDave Jiang1-7/+41
The transport right now does not handle the case where we run out of DMA descriptors. We just fail when we do not succeed. Adding code to retry for a bit attempting to use the DMA engine instead of instantly fail to CPU copy. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-01-11NTB: Clear property bits in BAR valueDave Jiang2-2/+5
The lower bits read from a BAR register will contain property bits that we do not care about. Clear those so that we can use the BAR values for limit and xlat registers. Reported-by: Conrad Meyer <cem@freebsd.org> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-01-11NTB: ntb_process_tx error path bugJon Mason1-1/+1
The transmit overrun avoidance error path in ntb_process_tx accidentally swapped the first two values being passed to the tx_handler client. This could result in crashes in the ntb_netdev (or other out-of-tree NTB clients). Reported-by: Alex Depoutovitch <alex@pernixdata.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: fix 32-bit compiler warningArnd Bergmann1-2/+2
resource_size_t may be 32-bit wide on some architectures, which causes this warning when building the NTB code: drivers/ntb/ntb_transport.c: In function 'ntb_transport_link_work': drivers/ntb/ntb_transport.c:828:46: warning: right shift count >= width of type [-Wshift-count-overflow] The warning is harmless but can be avoided by using the upper_32_bits() macro. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: e26a5843f7f5 ("NTB: Split ntb_hw_intel and ntb_transport drivers") Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: unify translation addressesDave Jiang2-18/+13
There is no need for the upstream and downstream addresses to be different for the NTB configs. Go to using a single set of address. It is still possible to configure them differently using module parameter override however. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked and Tested-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: invalid buf pointer in multi-MW setupsJon Mason1-2/+2
Order of operations issue with the QP Num and MW count, which would result in the receive buffer pointer being invalid if there are more than 1 MW. Corrected with parenthesis to enforce the proper order of operations. Reported-by: John I. Kading <John.Kading@gd-ms.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: remove unused variableSudip Mukherjee1-4/+0
These variables were not used anywhere. So remove them. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: fix access of free-ed pointerSudip Mukherjee1-8/+7
We were accessing nt->mw_vec after freeing it. Fix the error path so that we free nt->mw_vec after we have finished using it. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-11-08NTB: Fix issue where we may be accessing NULL ptrDave Jiang1-8/+9
smatch detected an issue in the function ntb_transport_max_size() where we could be dereferencing a dma channel pointer when it is NULL. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Fix range check on memory window indexAllen Hubbe1-1/+1
The range check must exclude the upper bound. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Improve index handling in B2B MW workaroundAllen Hubbe1-6/+16
Check that b2b_mw_idx is in range of the number of memory windows when initializing the device. The workaround is considered to be in effect only if the device b2b_idx is exactly UINT_MAX, instead of any index past the last memory window. Only print B2B MW workaround information in debugfs if the workaround is in effect. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Use unique DMA channels for TX and RXDave Jiang1-19/+58
Allocate two DMA channels, one for TX operation and one for RX operation, instead of having one DMA channel for everything. This provides slightly better performance, and also will make error handling cleaner later on. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Remove dma_sync_wait from ntb_async_rxAllen Hubbe1-9/+3
The dma_sync_wait can hurt the performance of workloads mixed with both large and small frames. Large frames will be copied using the dma engine. Small frames will be copied by the cpu. The dma_sync_wait prevents the cpu and dma engine copying in parallel. In the period where the cpu is copying, the dma engine is stopped. The dma engine is not doing any useful work to copy large frames during that time, and the additional time to restart the dma engine for the next large frame. This will decrease the throughput for the portion of a workload with large frames. In the period where the dma engine is copying, the cpu is held up waiting for dma to complete. The small frames processing will be delayed until the dma is complete. The RX frames are completed in-order, and the processing of small frames takes very little time, so dma_sync_wait may have an insignificant impact on the respose time of frames. The more significant impact is to the system, because the delay in dma_sync_wait is implemented as busy non-blocking wait. This can prevent the delayed core from doing any useful work, even if it could be processing work for other drivers, unrelated to transport RX processing. After applying the earlier patch to fix out-of-order RX acknoledgement, the dma_sync_wait is no longer necessary. Remove it, so that cpu memcpy will proceed immediately for small frames, in parallel with ongoing dma for large frames. Do not hold up the cpu from doing work while dma is in progress. The prior fix will continue to ensure in-order completion of the RX frames to the upper layer, and in-order delivery of the RX acknoledgement. Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Clean up QP stats infoDave Jiang1-9/+16
Make QP stats info more readable for debugging purposes. Also add an entry to indicate whether DMA is being used. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-09-07NTB: Make the transport list in order of discoveryDave Jiang1-1/+1
The list should be added from the bottom and not the top in order to ensure the transport is provided in the same order to clients as ntb devices are discovered. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Jon Mason <jdmason@kudzu.us>
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