doc(release): release notes for v2.1.0

Signed-off-by: Raphael Defosseux <raphael.defosseux@openairinterface.org>

CHANGELOG.md

 # RELEASE NOTES: #
 
+## v2.1.0 -- August 2024 ##
+
+* Features
+  - Add connection handling between UPF and NRF
+  - Use HTTP Request Timeout parameter from Conf file
+  - QoS initial support
+  - N4 interoperability improved
+  - Performance improvement: CPU usage is further reduced
+* Fixes
+  - Fixes: thread management especially at shutdown.
+  - Fix FDQN IPv4-only resolution
+  - Fix Using SD in string hex in UPF profile to send to NRF
+  - Fix to update TEID after a reconnection with FiveG_S_TMSI
+* Tech Debt
+  - Stopping support for RHEL8/Rocky8 in favor of RHEL9/Rocky9
+  - Remove NRF dependency from UPF
+  - HTTP client cpr library refactoring effort
+  - Bumping up libbpf and bpftool versions:
+    - libbpf to `master` (currently above `v1.4.5`)
+    - bpftool to `v7.3.0`
+    - This should allow to build on newer systems
+
 ## v2.0.0 -- December 2023 ##
 
 * Features

common-build @ 0968c25e

-Subproject commit 062267b9372583ef181f7205ba58c9b6f2b12301
+Subproject commit 0968c25ea2414dac69181dc57a23ee17848c3111

build/scripts/build_helper.upf

@@ -121,12 +121,17 @@ install_libbpf_from_git() {
         python3"
     fi
     $SUDO $INSTALLER install -y $PACKAGE_LIST
-    cd libbpf 
-    #&& git checkout 051a4009f94d5633a8f734ca4235f0a78ee90469
+    cd libbpf
+    # we used to checkout to 051a4009f94d5633a8f734ca4235f0a78ee90469 (aka v0.3)
+    # that was restricting us to build on 5.1xx kernel hosts
+    # we are now back on the master branch (latest tag at time of writing is v1.4.5)
+    # displaying the last commit version
+    git log -n1
     ret=$?;[[ $ret -ne 0 ]] && popd && return $ret
-    cd src && make -j $(nproc) 
+    cd src && make -j $(nproc)
     ret=$?;[[ $ret -ne 0 ]] && popd && return $ret
     $SUDO make install
+    ret=$?;[[ $ret -ne 0 ]] && popd && return $ret
     popd
   fi
   echo "libbpf installation complete"
@@ -199,9 +204,6 @@ install_bpftool_from_git() {
 
   if [[ $prompt =~ [yY](es)* ]]
   then
-    #GIT_URL=https://github.com/libbpf/bpftool.git
-    #GIT_URL=https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/snapshot/linux-$KERNEL_VERSION.tar.gz
-    
     GIT_URL=https://github.com/libbpf/bpftool.git
     echo "Install bpftool from $GIT_URL"
     pushd $OPENAIRCN_DIR/build/ext
@@ -211,6 +213,7 @@ install_bpftool_from_git() {
       $SUDO rm -rf bpftool
     fi
 
+    # Checkout to tested version
     git clone --branch v7.3.0 --recurse-submodules $GIT_URL
 
     if [[ $OS_DISTRO == "ubuntu" ]]; then
@@ -218,22 +221,13 @@ install_bpftool_from_git() {
     elif [[ "$OS_BASEDISTRO" == "fedora" ]]; then
       $SUDO $INSTALLER install -y wget
     fi
-    
-    # trick for CI
-    #if [ ! -f $OPENAIRCN_DIR/build/ext/linux-$KERNEL_VERSION.tar.gz ]; then
-    #  wget -nv --tries=4 --retry-connrefused --wait=8 $GIT_URL
-    #  ret=$?;[[ $ret -ne 0 ]] && popd && return $ret
-    #fi
-    #ls -lst linux-$KERNEL_VERSION.tar.gz && tar -xf linux-$KERNEL_VERSION.tar.gz && rm -rf linux-$KERNEL_VERSION.tar.gz
 
     cd bpftool
     ret=$?;[[ $ret -ne 0 ]] && popd && return $ret
-    #cd linux-$KERNEL_VERSION/tools/bpf/bpftool && make -j $(nproc)
     cd src && CLANG=Nope make -j $(nproc)
     ret=$?;[[ $ret -ne 0 ]] && popd && return $ret
     $SUDO make install
-    #ret=$?;[[ $ret -ne 0 ]] && popd && return $ret
-    #$SUDO rm -rf linux-$KERNEL_VERSION
+    ret=$?;[[ $ret -ne 0 ]] && popd && return $ret
     popd
   fi
   echo "bpftool installation complete"
@@ -354,11 +348,11 @@ check_install_upf_deps() {
   ret=$?;[[ $ret -ne 0 ]] && return $ret
 
   echo_info "distro libs installation complete"
-  
+
   echo ""
   echo "Auto-detecting UPF features:"
   check_enable_bpf_datapath
-  if [ $? -eq 0 ]; then  
+  if [ $? -eq 0 ]; then
     check_enable_qos
     if [ $? -eq 0 ]; then
       echo -e "     BPF Datapath: [$GREEN on $NC  ]"
@@ -373,8 +367,8 @@ check_install_upf_deps() {
     echo -e "     BPF Datapath: [$RED off $NC ]"
     echo -e "      QoS Feature: [$RED off $NC ]"
     echo ""
-  fi  
-  
+  fi
+
   echo -e "$YELLOW WARNINGS: "
   echo -e "           1. Even when "BPF Datapath" and/or "QoS Feature" are/is disabled"
   echo -e "              we still build and install BPF and Netlinks libraries."
@@ -406,9 +400,9 @@ check_install_upf_deps() {
 
   install_nlohmann_from_git $1 $2
   ret=$?;[[ $ret -ne 0 ]] && return $ret
-  
+
   install_cpr_from_git $1 $2
-  ret=$?;[[ $ret -ne 0 ]] && return $ret 
+  ret=$?;[[ $ret -ne 0 ]] && return $ret
 
   # latest usage of yaml-cpp suggests that we should be using 0.7+ version
   # To be sure, let's install from source all the time for the moment