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  1. 08 4月, 2017 9 次提交
  3. 07 4月, 2017 4 次提交
  5. 06 4月, 2017 7 次提交
    • N
      fm10k: do not enqueue mailbox when host not ready · 7d4fe0d1
      由 Ngai-Mint Kwan 提交于 
      Interfaces will reset whenever the TX mailbox FIFO has become full. This
occurs more frequently whenever the IES API application is not running
to process and clear the messages in the FIFO. Thus, this could lead to
situations where the interface would enter an infinite reset loop. That
is: if the interface is trying to synchronize a huge number of unicast
and multicast entries with the IES API application, the TX mailbox FIFO
will become full and the interface resets. Once the interface exits
reset, it'll try to synchronize the unicast and multicast entries again.
Ergo, this creates an infinite loop. Other actions such as multiple
mulitcast mode or up/down transitions will fill the TX mailbox FIFO and
induce the interface to reset. To correct these situations, check if the
interface's "host_ready" flag is enabled before enqueuing any messages
to the TX mailbox FIFO. This check will be conducted by a function call.
Lastly, this issue mainly affects the PF and, thus, the VF is exempt.
Signed-off-by: NNgai-Mint Kwan <ngai-mint.kwan@intel.com>
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NKrishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
      7d4fe0d1
    • N
      fm10k: disable receive queue when configuring ring · 16b1889f
      由 Ngai-Mint Kwan 提交于 
      Write to RXQCTL register to disable the receive queue when configuring
the RX ring.
Signed-off-by: NNgai-Mint Kwan <ngai-mint.kwan@intel.com>
Tested-by: NKrishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
      16b1889f
    • J
      fm10k: update function header comment for fm10k_get_stats64 · 02957703
      由 Jacob Keller 提交于 
      Re-word the comment to avoid stating that we return a value for this
void function. Additionally, there is no need to mention older kernels,
since this is the upstream kernel.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NKrishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
      02957703
    • J
      fm10k: allow service task to reschedule itself · b4fd8ffc
      由 Jacob Keller 提交于 
      If some code path executes fm10k_service_event_schedule(), it is
guaranteed that we only queue the service task once, since we use
__FM10K_SERVICE_SCHED flag. Unfortunately this has a side effect that if
a service request occurs while we are currently running the watchdog, it
is possible that we will fail to notice the request and ignore it until
the next time the request occurs.

This can cause problems with pf/vf mailbox communication and other
service event tasks. To avoid this, introduce a FM10K_SERVICE_REQUEST
bit. When we successfully schedule (and set the _SCHED bit) the service
task, we will clear this bit. However, if we are unable to currently
schedule the service event, we just set the new SERVICE_REQUEST bit.

Finally, after the service event completes, we will re-schedule if the
request bit has been set.

This should ensure that we do not miss any service event schedules,
since we will re-schedule it once the currently running task finishes.
This means that for each request, we will always schedule the service
task to run at least once in full after the request came in.

This will avoid timing issues that can occur with the service event
scheduling. We do pay a cost in re-running many tasks, but all the
service event tasks use either flags to avoid duplicate work, or are
tolerant of being run multiple times.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NKrishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
      b4fd8ffc
    • J
      fm10k: future-proof state bitmaps using DECLARE_BITMAP · 46929557
      由 Jacob Keller 提交于 
      This ensures that future programmers do not have to remember to re-size
the bitmaps due to adding new values. Although this is unlikely for this
driver, it may happen and it's best to prevent it from ever being an
issue.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NKrishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
      46929557
    • J
      fm10k: use a BITMAP for flags to avoid race conditions · 3ee7b3a3
      由 Jacob Keller 提交于 
      Replace bitwise operators and #defines with a BITMAP and enumeration
values. This is similar to how we handle the "state" values as well.

This has two distinct advantages over the old method. First, we ensure
correctness of operations which are currently problematic due to race
conditions. Suppose that two kernel threads are running, such as the
watchdog and an ethtool ioctl, and both modify flags. We'll say that the
watchdog is CPU A, and the ethtool ioctl is CPU B.

CPU A sets FLAG_1, which can be seen as
  CPU A read FLAGS
  CPU A write FLAGS | FLAG_1

CPU B sets FLAG_2, which can be seen as
  CPU B read FLAGS
  CPU A write FLAGS | FLAG_2

However, "|=" and "&=" operators are not actually atomic. So this could
be ordered like the following:

CPU A read FLAGS -> variable
CPU B read FLAGS -> variable
CPU A write FLAGS (variable | FLAG_1)
CPU B write FLAGS (variable | FLAG_2)

Notice how the 2nd write from CPU B could actually undo the write from
CPU A because it isn't guaranteed that the |= operation is atomic.

In practice the race windows for most flag writes is incredibly narrow
so it is not easy to isolate issues. However, the more flags we have,
the more likely they will cause problems. Additionally, if such
a problem were to arise, it would be incredibly difficult to track down.

Second, there is an additional advantage beyond code correctness. We can
now automatically size the BITMAP if more flags were added, so that we
do not need to remember that flags is u32 and thus if we added too many
flags we would over-run the variable. This is not a likely occurrence
for fm10k driver, but this patch can serve as an example for other
drivers which have many more flags.

This particular change does have a bit of trouble converting some of the
idioms previously used with the #defines for flags. Specifically, when
converting FM10K_FLAG_RSS_FIELD_IPV[46]_UDP flags. This whole operation
was actually quite problematic, because we actually stored flags
separately. This could more easily show the problem of the above
re-ordering issue.

This is really difficult to test whether atomics make a difference in
practical scenarios, but you can ensure that basic functionality remains
the same. This patch has a lot of code coverage, but most of it is
relatively simple.

While we are modifying these files, update their copyright year.
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Tested-by: NKrishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
      3ee7b3a3
    • P
      fm10k: correctly check if interface is removed · 540fca35
      由 Phil Turnbull 提交于 
      FM10K_REMOVED expects a hardware address, not a 'struct fm10k_hw'.

Fixes: 5cb8db4a ("fm10k: Add support for VF")
Signed-off-by: NPhil Turnbull <phil.turnbull@oracle.com>
Tested-by: NKrishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
      540fca35
  7. 31 3月, 2017 1 次提交
  9. 29 3月, 2017 13 次提交
  11. 28 3月, 2017 6 次提交