ipcpd: Use the kernel scheduler for QoS

This revises the sdu_scheduler of the normal IPCP to create a
scheduler thread per QoS cube and let the kernel scheduler schedule
them based on a priority. Priorities can be set at build time in a
range of 0-100, which will be mapped onto a suitable priority for the
kernel scheduler. The current scheduler policy is fixed to SCHED_RR
since it is the most suitable scheduler defined by POSIX.

1 files changed, 18 insertions, 2 deletions

diff --git a/src/ipcpd/CMakeLists.txt b/src/ipcpd/CMakeLists.txt
index 6356b1ba..a71c4e98 100644
--- a/src/ipcpd/CMakeLists.txt
+++ b/src/ipcpd/CMakeLists.txt
@@ -1,12 +1,28 @@
 set(IPCP_ACCEPT_TIMEOUT 100 CACHE STRING
   "Timeout for accept in IPCP mainloop threads (ms)")
-set(IPCP_SCHED_THREADS 2 CACHE STRING
-  "Number of scheduler threads in the normal IPCP")
+set(IPCP_QOS_CUBE_BE_PRIO 0 CACHE STRING
+  "Priority for best effort QoS cube (0-99)")
+set(IPCP_QOS_CUBE_VIDEO_PRIO 90 CACHE STRING
+  "Priority for video QoS cube (0-99)")
+set(IPCP_QOS_CUBE_VOICE_PRIO 99 CACHE STRING
+  "Priority for voice QoS cube (0-99)")
 set(IPCP_MIN_THREADS 4 CACHE STRING
   "Minimum number of worker threads in the IPCP")
 set(IPCP_ADD_THREADS 4 CACHE STRING
   "Number of extra threads to start when an IPCP faces thread starvation")
 
+if ((IPCP_QOS_CUBE_BE_PRIO LESS 0) OR (IPCP_QOS_CUBE_BE_PRIO GREATER 99))
+  message(FATAL_ERROR "Invalid priority for best effort QoS cube")
+endif ()
+
+if ((IPCP_QOS_CUBE_VIDEO_PRIO LESS 0) OR (IPCP_QOS_CUBE_VIDEO_PRIO GREATER 99))
+  message(FATAL_ERROR "Invalid priority for video QoS cube")
+endif ()
+
+if ((IPCP_QOS_CUBE_VOICE_PRIO LESS 0) OR (IPCP_QOS_CUBE_VOICE_PRIO GREATER 99))
+  message(FATAL_ERROR "Invalid priority for voice QoS cube")
+endif ()
+
 set(IPCP_SOURCES
   # Add source files here
   ${CMAKE_CURRENT_SOURCE_DIR}/ipcp.c