scftorture: Count single_rpc offline failures in statistics outputgrafted

scf_torture_stats_print() aggregates each invoker thread's counters
into a local scf_statistics structure before printing, but the
n_single_rpc_ofl field is missing from the aggregation loop.  As a
result, the "single_rpc_ofl" value printed in the statistics line is
always zero, even when smp_call_function_single() invocations for the
RPC test have failed due to offline CPUs and been counted by the
invoker threads.

Add the missing accumulation so that the printed value reflects the
actual counts.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

1 files changed, 100 insertions, 0 deletions

diff --git a/samples/vfio-mdev/README.rst b/samples/vfio-mdev/README.rst
new file mode 100644
index 000000000..b52eb3773
--- /dev/null
+++ b/samples/vfio-mdev/README.rst
@@ -0,0 +1,100 @@
+Using the mtty vfio-mdev sample code
+====================================
+
+mtty is a sample vfio-mdev driver that demonstrates how to use the mediated
+device framework.
+
+The sample driver creates an mdev device that simulates a serial port over a PCI
+card.
+
+1. Build and load the mtty.ko module.
+
+   This step creates a dummy device, /sys/devices/virtual/mtty/mtty/
+
+   Files in this device directory in sysfs are similar to the following::
+
+     # tree /sys/devices/virtual/mtty/mtty/
+        /sys/devices/virtual/mtty/mtty/
+        |-- mdev_supported_types
+        |   |-- mtty-1
+        |   |   |-- available_instances
+        |   |   |-- create
+        |   |   |-- device_api
+        |   |   |-- devices
+        |   |   `-- name
+        |   `-- mtty-2
+        |       |-- available_instances
+        |       |-- create
+        |       |-- device_api
+        |       |-- devices
+        |       `-- name
+        |-- mtty_dev
+        |   `-- sample_mtty_dev
+        |-- power
+        |   |-- autosuspend_delay_ms
+        |   |-- control
+        |   |-- runtime_active_time
+        |   |-- runtime_status
+        |   `-- runtime_suspended_time
+        |-- subsystem -> ../../../../class/mtty
+        `-- uevent
+
+2. Create a mediated device by using the dummy device that you created in the
+   previous step::
+
+     # echo "83b8f4f2-509f-382f-3c1e-e6bfe0fa1001" >	\
+              /sys/devices/virtual/mtty/mtty/mdev_supported_types/mtty-2/create
+
+3. Add parameters to qemu-kvm::
+
+     -device vfio-pci,\
+      sysfsdev=/sys/bus/mdev/devices/83b8f4f2-509f-382f-3c1e-e6bfe0fa1001
+
+4. Boot the VM.
+
+   In the Linux guest VM, with no hardware on the host, the device appears
+   as  follows::
+
+     # lspci -s 00:05.0 -xxvv
+     00:05.0 Serial controller: Device 4348:3253 (rev 10) (prog-if 02 [16550])
+             Subsystem: Device 4348:3253
+             Physical Slot: 5
+             Control: I/O+ Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr-
+     Stepping- SERR- FastB2B- DisINTx-
+             Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort-
+     <TAbort- <MAbort- >SERR- <PERR- INTx-
+             Interrupt: pin A routed to IRQ 10
+             Region 0: I/O ports at c150 [size=8]
+             Region 1: I/O ports at c158 [size=8]
+             Kernel driver in use: serial
+     00: 48 43 53 32 01 00 00 02 10 02 00 07 00 00 00 00
+     10: 51 c1 00 00 59 c1 00 00 00 00 00 00 00 00 00 00
+     20: 00 00 00 00 00 00 00 00 00 00 00 00 48 43 53 32
+     30: 00 00 00 00 00 00 00 00 00 00 00 00 0a 01 00 00
+
+     In the Linux guest VM, dmesg output for the device is as follows:
+
+     serial 0000:00:05.0: PCI INT A -> Link[LNKA] -> GSI 10 (level, high) -> IRQ 10
+     0000:00:05.0: ttyS1 at I/O 0xc150 (irq = 10) is a 16550A
+     0000:00:05.0: ttyS2 at I/O 0xc158 (irq = 10) is a 16550A
+
+
+5. In the Linux guest VM, check the serial ports::
+
+     # setserial -g /dev/ttyS*
+     /dev/ttyS0, UART: 16550A, Port: 0x03f8, IRQ: 4
+     /dev/ttyS1, UART: 16550A, Port: 0xc150, IRQ: 10
+     /dev/ttyS2, UART: 16550A, Port: 0xc158, IRQ: 10
+
+6. Using minicom or any terminal emulation program, open port /dev/ttyS1 or
+   /dev/ttyS2 with hardware flow control disabled.
+
+7. Type data on the minicom terminal or send data to the terminal emulation
+   program and read the data.
+
+   Data is loop backed from hosts mtty driver.
+
+8. Destroy the mediated device that you created::
+
+     # echo 1 > /sys/bus/mdev/devices/83b8f4f2-509f-382f-3c1e-e6bfe0fa1001/remove
+