Commit Graph

6 Commits

Author SHA1 Message Date
Greg Kroah-Hartman
5c43276499 infiniband: hfi1: drop crazy DEBUGFS_SEQ_FILE_CREATE() macro
The macro was just making things harder to follow, and audit, so remove
it and call debugfs_create_file() directly.  Also, the macro did not
need to warn about the call failing as no one should ever care about any
debugfs functions failing.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-01-24 09:22:29 -07:00
Doug Ledford
009669cfad RDMA/hfi1: Fix build error with debugfs disabled
A recent patch set to rework the usage of debugfs and to add fault
injection capabilities via debugfs files to the hfi1 driver introduced a
build error that only shows up when debugfs is fully disabled.  The
patchset mistakenly defines some empty stub functions in two different
headers when debugfs is disabled.  Remove the set that shouldn't have
been there to resolve the issue.

Fixes: a74d5307ca ("IB/hfi1: Rework fault injection machinery")
Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-05-15 14:24:18 -04:00
Mitko Haralanov
a74d5307ca IB/hfi1: Rework fault injection machinery
The packet fault injection code present in the HFI1 driver had some
issues which not only fragment the code but also created user
confusion. Furthermore, it suffered from the following issues:

  1. The fault_packet method only worked for received packets. This
     meant that the only fault injection mode available for sent
     packets is fault_opcode, which did not allow for random packet
     drops on all egressing packets.
  2. The mask available for the fault_opcode mode did not really work
     due to the fact that the opcode values are not bits in a bitmask but
     rather sequential integer values. Creating a opcode/mask pair that
     would successfully capture a set of packets was nearly impossible.
  3. The code was fragmented and used too many debugfs entries to
     operate and control. This was confusing to users.
  4. It did not allow filtering fault injection on a per direction basis -
     egress vs. ingress.

In order to improve or fix the above issues, the following changes have
been made:

   1. The fault injection methods have been combined into a single fault
      injection facility. As such, the fault injection has been plugged
      into both the send and receive code paths. Regardless of method used
      the fault injection will operate on both egress and ingress packets.
   2. The type of fault injection - by packet or by opcode - is now controlled
      by changing the boolean value of the file "opcode_mode". When the value
      is set to True, fault injection is done by opcode. Otherwise, by
      packet.
   2. The masking ability has been removed in favor of a bitmap that holds
      opcodes of interest (one bit per opcode, a total of 256 bits). This
      works in tandem with the "opcode_mode" value. When the value of
      "opcode_mode" is False, this bitmap is ignored. When the value is
      True, the bitmap lists all opcodes to be considered for fault injection.
      By default, the bitmap is empty. When the user wants to filter by opcode,
      the user sets the corresponding bit in the bitmap by echo'ing the bit
      position into the 'opcodes' file. This gets around the issue that the set
      of opcodes does not lend itself to effective masks and allow for extremely
      fine-grained filtering by opcode.
   4. fault_packet and fault_opcode methods have been combined. Hence, there
      is only one debugfs directory controlling the entire operation of the
      fault injection machinery. This reduces the number of debugfs entries
      and provides a more unified user experience.
   5. A new control files - "direction" - is provided to allow the user to
      control the direction of packets, which are subject to fault injection.
   6. A new control file - "skip_usec" - is added that would allow the user
      to specify a "timeout" during which no fault injection will occur.

In addition, the following bug fixes have been applied:

   1. The fault injection code has been split into its own header and source
      files. This was done to better organize the code and support conditional
      compilation without littering the code with #ifdef's.
   2. The method by which the TX PIO packets were being marked for drop
      conflicted with the way send contexts were being setup. As a result,
      the send context was repeatedly being reset.
   3. The fault injection only makes sense when the user can control it
      through the debugfs entries. However, a kernel configuration can
      enable fault injection but keep fault injection debugfs entries
      disabled. Therefore, it makes sense that the HFI fault injection
      code depends on both.
   4. Error suppression did not take into account the method by which PIO
      packets were being dropped. Therefore, even with error suppression
      turned on, errors would still be displayed to the screen. A larger
      enough packet drop percentage would case the kernel to crash because
      the driver would be stuck printing errors.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Don Hiatt <don.hiatt@intel.com>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-05-09 15:53:30 -04:00
Don Hiatt
243d9f436f IB/hfi1: Add transmit fault injection feature
Add ability to fault packets on transmit by opcode.
Dropping by packet can be achieved by setting the mask to 0.

In order to drop non-verbs traffic we set PbcInsertHrc
to NONE (0x2). The packet will still be delivered to
the receiving node but a KHdrHCRCErr (KDETH packet
with a bad HCRC) will be triggered and the packet will
not be delivered to the correct context.

In order to drop regular verbs traffic we set the
PbcTestEbp flag. The packet will still be delivered
to the receiving node but a 'late ebp error' will
be triggered and will be dropped.

A global toggle (/sys/kernel/debug/hfi1/hfi1_X/fault_suppress_err)
has been added to suppress the error messages on the receive
node when a packet was faulted on the sending node.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Don Hiatt <don.hiatt@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-04-05 14:45:09 -04:00
Don Hiatt
0181ce31b2 IB/hfi1: Add receive fault injection feature
Add fault injection capability:
  - Drop packets unconditionally (fault_by_packet)
  - Drop packets based on opcode (fault_by_opcode)

This feature reacts to the global FAULT_INJECTION
config flag.

The faulting traces have been added:
  - misc/fault_opcode
  - misc/fault_packet

See 'Documentation/fault-injection/fault-injection.txt'
for details.

Examples:
  - Dropping packets by opcode:
    /sys/kernel/debug/hfi1/hfi1_X/fault_opcode
	# Enable fault
	echo Y > fault_by_opcode
	# Setprobability of dropping (0-100%)
	# echo 25 > probability
	# Set opcode
	echo 0x64 > opcode
	# Number of times to fault
	echo 3 > times
	# An optional mask allows you to fault
	# a range of opcodes
	echo 0xf0 > mask
    /sys/kernel/debug/hfi1/hfi1_X/fault_stats
    contains a value in parentheses to indicate
    number of each opcode dropped.

  - Dropping packets unconditionally
    /sys/kernel/debug/hfi1/hfi1_X/fault_packet
	# Enable fault
	echo Y > fault_by_packet
    /sys/kernel/debug/hfi1/hfi1_X/fault_packet/fault_stats
    contains the number of packets dropped.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Don Hiatt <don.hiatt@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-04-05 14:45:09 -04:00
Dennis Dalessandro
f48ad614c1 IB/hfi1: Move driver out of staging
The TODO list for the hfi1 driver was completed during 4.6. In addition
other objections raised (which are far beyond what was in the TODO list)
have been addressed as well. It is now time to remove the driver from
staging and into the drivers/infiniband sub-tree.

Reviewed-by: Jubin John <jubin.john@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-05-26 11:35:14 -04:00