Commit Graph

21 Commits

Author SHA1 Message Date
Logan Gunthorpe 35539b54ac ntb_perf: clear link_is_up flag when the link goes down.
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>
2016-08-05 10:21:08 -04:00
Logan Gunthorpe 20572ee1c5 ntb_pingpong: Add a debugfs file to get the ping count
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>
2016-08-05 10:21:07 -04:00
Logan Gunthorpe bfcaa39652 ntb_tool: Add link status and files to debugfs
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>
2016-08-05 10:21:07 -04:00
Logan Gunthorpe 717146a2a8 ntb_tool: Postpone memory window initialization for the user
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>
2016-08-05 10:21:07 -04:00
Logan Gunthorpe 26dc638ae6 ntb_perf: Wait for link before running test
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>
2016-08-05 10:21:07 -04:00
Logan Gunthorpe 58fd0f3b15 ntb_perf: Return results by reading the run file
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>
2016-08-05 10:21:07 -04:00
Logan Gunthorpe da573eaa3a ntb_perf: Improve thread handling to increase robustness
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>
2016-08-05 10:21:06 -04:00
Logan Gunthorpe fd2ecd885b ntb_perf: Schedule based on time not on performance
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>
2016-08-05 10:21:06 -04:00
Logan Gunthorpe 19645a0771 ntb_transport: Check the number of spads the hardware supports
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>
2016-08-05 10:21:06 -04:00
Logan Gunthorpe 8b71d28506 ntb_tool: Add memory window debug support
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>
2016-08-05 10:21:06 -04:00
Logan Gunthorpe 4aae977721 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 <logang@deltatee.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-08-05 10:21:06 -04:00
Logan Gunthorpe 625f0802e8 ntb_tool: BUG: Ensure the buffer size is large enough to return all spads
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>
2016-08-05 10:05:31 -04:00
Logan Gunthorpe c792eba12c ntb_tool: Fix infinite loop bug when writing spad/peer_spad file
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>
2016-08-05 10:05:31 -04:00
Dave Jiang 838850ee0b NTB: Fix incorrect clean up routine in ntb_perf
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>
2016-03-21 19:28:30 -04:00
Dave Jiang ddc8f6feec NTB: Fix incorrect return check in ntb_perf
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>
2016-03-21 19:28:25 -04:00
Sudip Mukherjee 2572c7fb4e ntb: fix possible NULL dereference
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>
2016-03-17 20:52:15 -04:00
Dave Jiang ee5f750f1c ntb: add missing setup of translation window
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>
2016-03-17 20:50:15 -04:00
Arnd Bergmann 1985a88107 ntb: perf test: fix address space confusion
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: 8a7b6a778a ("ntb: ntb perf tool")
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2016-03-17 20:38:40 -04:00
Dave Jiang 8a7b6a778a ntb: ntb perf tool
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>
2016-01-17 22:08:05 -05:00
Allen Hubbe 578b881ba9 NTB: Add tool test client
This is a simple debugging driver that enables the doorbell and
scratch pad registers to be read and written from the debugfs.  This
tool enables more complicated debugging to be scripted from user space.
This driver may be used to test that your ntb hardware and drivers are
functioning at a basic level.

Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04 14:08:17 -04:00
Allen Hubbe 963de4739f NTB: Add ping pong test client
This is a simple ping pong driver that exercises the scratch pads and
doorbells of the ntb hardware.  This driver may be used to test that
your ntb hardware and drivers are functioning at a basic level.

Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
2015-07-04 14:07:42 -04:00