lib: Replace rdrbuff with a proper slab allocatorbe

This is a first step towards the Secure Shared Memory (SSM)
infrastructure for Ouroboros, which will allow proper resource
separation for non-privileged processes.

This replaces the rdrbuff (random-deletion ring buffer) PoC allocator
with a sharded slab allocator for the packet buffer pool to avoid the
head-of-line blocking behaviour of the rdrb and reduce lock contention
in multi-process scenarios. Each size class contains multiple
independent shards, allowing parallel allocations without blocking.

- Configurable shard count per size class (default: 4, set via
  SSM_POOL_SHARDS in CMake). The configured number of blocks are
  spread over the number of shards. As an example:

  	 SSM_POOL_512_BLOCKS = 768 blocks total
	 These 768 blocks are shared among 4 shards
	       (not 768 × 4 = 3072 blocks)

- Lazy block distribution: all blocks initially reside in shard 0
  and naturally migrate to process-local shards upon first
  allocation and subsequent free operations

- Fallback with work stealing: processes attempt allocation from
  their local shard (pid % SSM_POOL_SHARDS) first, then steal
  from other shards if local is exhausted, eliminating
  fragmentation while maintaining low contention

- Round-robin condvar signaling: blocking allocations cycle
  through all shard condition variables to ensure fairness

- Blocks freed to allocator's shard: uses allocator_pid to
  determine target shard, enabling natural load balancing as
  process allocation patterns stabilize over time

Maintains existing robust mutex semantics including EOWNERDEAD
handling for dead process recovery. Internal structures exposed in
ssm.h for testing purposes. Adds some tests (pool_test,
pool_sharding_test.c. etc) verifying lazy distribution, migration,
fallback stealing, and multiprocess behavior.

Updates the ring buffer (rbuff) to use relaxed/acquire/release
ordering on atomic indices. The ring buffer requires the (robust)
mutex to ensure cross-structure synchronization between pool buffer
writes and ring buffer index publication.

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

9 files changed, 110 insertions, 110 deletions

diff --git a/src/ipcpd/unicast/dir/dht.c b/src/ipcpd/unicast/dir/dht.c
index 1388c2de..69309091 100644
--- a/src/ipcpd/unicast/dir/dht.c
+++ b/src/ipcpd/unicast/dir/dht.c
@@ -2266,7 +2266,7 @@ static int dht_send_msg(dht_msg_t * msg,
                         uint64_t    addr)
 {
         size_t               len;
-        struct shm_du_buff * sdb;
+        struct ssm_pk_buff * spb;
 
         if (msg == NULL)
                 return 0;
@@ -2279,21 +2279,21 @@ static int dht_send_msg(dht_msg_t * msg,
                 goto fail_msg;
         }
 
-        if (ipcp_sdb_reserve(&sdb, len)) {
-                log_warn("%s failed to get sdb.", DHT_CODE(msg));
+        if (ipcp_spb_reserve(&spb, len)) {
+                log_warn("%s failed to get spb.", DHT_CODE(msg));
                 goto fail_msg;
         }
 
-        dht_msg__pack(msg, shm_du_buff_head(sdb));
+        dht_msg__pack(msg, ssm_pk_buff_head(spb));
 
-        if (dt_write_packet(addr, QOS_CUBE_BE, dht.eid, sdb) < 0) {
+        if (dt_write_packet(addr, QOS_CUBE_BE, dht.eid, spb) < 0) {
                 log_warn("%s write failed", DHT_CODE(msg));
                 goto fail_send;
         }
 
         return 0;
  fail_send:
-        ipcp_sdb_release(sdb);
+        ipcp_spb_release(spb);
  fail_msg:
         return -1;
 }
@@ -3191,7 +3191,7 @@ static void * dht_handle_packet(void * o)
 }
 #ifndef __DHT_TEST__
 static void dht_post_packet(void *               comp,
-                            struct shm_du_buff * sdb)
+                            struct ssm_pk_buff * spb)
 {
         struct cmd * cmd;
 
@@ -3203,17 +3203,17 @@ static void dht_post_packet(void *               comp,
                 goto fail_cmd;
         }
 
-        cmd->cbuf.data = malloc(shm_du_buff_len(sdb));
+        cmd->cbuf.data = malloc(ssm_pk_buff_len(spb));
         if (cmd->cbuf.data == NULL) {
                 log_err("Command buffer malloc failed.");
                 goto fail_buf;
         }
 
-        cmd->cbuf.len = shm_du_buff_len(sdb);
+        cmd->cbuf.len = ssm_pk_buff_len(spb);
 
-        memcpy(cmd->cbuf.data, shm_du_buff_head(sdb), cmd->cbuf.len);
+        memcpy(cmd->cbuf.data, ssm_pk_buff_head(spb), cmd->cbuf.len);
 
-        ipcp_sdb_release(sdb);
+        ipcp_spb_release(spb);
 
         pthread_mutex_lock(&dht.cmds.mtx);
 
@@ -3228,7 +3228,7 @@ static void dht_post_packet(void *               comp,
  fail_buf:
         free(cmd);
  fail_cmd:
-        ipcp_sdb_release(sdb);
+        ipcp_spb_release(spb);
         return;
 }
 #endif
diff --git a/src/ipcpd/unicast/dir/tests/CMakeLists.txt b/src/ipcpd/unicast/dir/tests/CMakeLists.txt
index 3dda8104..dd15d4d8 100644
--- a/src/ipcpd/unicast/dir/tests/CMakeLists.txt
+++ b/src/ipcpd/unicast/dir/tests/CMakeLists.txt
@@ -28,7 +28,7 @@ create_test_sourcelist(${PARENT_DIR}_tests test_suite.c
   dht_test.c
   )
 
-protobuf_generate_c(DHT_PROTO_SRCS KAD_PROTO_HDRS ../dht.proto)
+protobuf_generate_c(DHT_PROTO_SRCS KAD_PROTO_HDRS ${CURRENT_SOURCE_PARENT_DIR}/dht.proto)
 add_executable(${PARENT_DIR}_test ${${PARENT_DIR}_tests}
   ${DHT_PROTO_SRCS})
 
diff --git a/src/ipcpd/unicast/dt.c b/src/ipcpd/unicast/dt.c
index e2679ffe..9435350f 100644
--- a/src/ipcpd/unicast/dt.c
+++ b/src/ipcpd/unicast/dt.c
@@ -68,7 +68,7 @@
 #endif
 
 struct comp_info {
-        void (* post_packet)(void * comp, struct shm_du_buff * sdb);
+        void (* post_packet)(void * comp, struct ssm_pk_buff * spb);
         void * comp;
         char * name;
 };
@@ -135,11 +135,11 @@ static void dt_pci_des(uint8_t *       head,
         memcpy(&dt_pci->eid, head + dt_pci_info.eid_o, dt_pci_info.eid_size);
 }
 
-static void dt_pci_shrink(struct shm_du_buff * sdb)
+static void dt_pci_shrink(struct ssm_pk_buff * spb)
 {
-        assert(sdb);
+        assert(spb);
 
-        shm_du_buff_head_release(sdb, dt_pci_info.head_size);
+        ssm_pk_buff_head_release(spb, dt_pci_info.head_size);
 }
 
 struct {
@@ -429,7 +429,7 @@ static void handle_event(void *       self,
 
 static void packet_handler(int                  fd,
                            qoscube_t            qc,
-                           struct shm_du_buff * sdb)
+                           struct ssm_pk_buff * spb)
 {
         struct dt_pci dt_pci;
         int           ret;
@@ -437,7 +437,7 @@ static void packet_handler(int                  fd,
         uint8_t *     head;
         size_t        len;
 
-        len = shm_du_buff_len(sdb);
+        len = ssm_pk_buff_len(spb);
 
 #ifndef IPCP_FLOW_STATS
         (void)        fd;
@@ -451,13 +451,13 @@ static void packet_handler(int                  fd,
 #endif
         memset(&dt_pci, 0, sizeof(dt_pci));
 
-        head = shm_du_buff_head(sdb);
+        head = ssm_pk_buff_head(spb);
 
         dt_pci_des(head, &dt_pci);
         if (dt_pci.dst_addr != dt.addr) {
                 if (dt_pci.ttl == 0) {
                         log_dbg("TTL was zero.");
-                        ipcp_sdb_release(sdb);
+                        ipcp_spb_release(spb);
 #ifdef IPCP_FLOW_STATS
                         pthread_mutex_lock(&dt.stat[fd].lock);
 
@@ -474,7 +474,7 @@ static void packet_handler(int                  fd,
                 if (ofd < 0) {
                         log_dbg("No next hop for %" PRIu64 ".",
                                 dt_pci.dst_addr);
-                        ipcp_sdb_release(sdb);
+                        ipcp_spb_release(spb);
 #ifdef IPCP_FLOW_STATS
                         pthread_mutex_lock(&dt.stat[fd].lock);
 
@@ -488,12 +488,12 @@ static void packet_handler(int                  fd,
 
                 (void) ca_calc_ecn(ofd, head + dt_pci_info.ecn_o, qc, len);
 
-                ret = ipcp_flow_write(ofd, sdb);
+                ret = ipcp_flow_write(ofd, spb);
                 if (ret < 0) {
                         log_dbg("Failed to write packet to fd %d.", ofd);
                         if (ret == -EFLOWDOWN)
                                 notifier_event(NOTIFY_DT_FLOW_DOWN, &ofd);
-                        ipcp_sdb_release(sdb);
+                        ipcp_spb_release(spb);
 #ifdef IPCP_FLOW_STATS
                         pthread_mutex_lock(&dt.stat[ofd].lock);
 
@@ -513,17 +513,17 @@ static void packet_handler(int                  fd,
                 pthread_mutex_unlock(&dt.stat[ofd].lock);
 #endif
         } else {
-                dt_pci_shrink(sdb);
+                dt_pci_shrink(spb);
                 if (dt_pci.eid >= PROG_RES_FDS) {
                         uint8_t ecn = *(head + dt_pci_info.ecn_o);
-                        fa_np1_rcv(dt_pci.eid, ecn, sdb);
+                        fa_np1_rcv(dt_pci.eid, ecn, spb);
                         return;
                 }
 
                 if (dt.comps[dt_pci.eid].post_packet == NULL) {
                         log_err("No registered component on eid %" PRIu64 ".",
                                 dt_pci.eid);
-                        ipcp_sdb_release(sdb);
+                        ipcp_spb_release(spb);
                         return;
                 }
 #ifdef IPCP_FLOW_STATS
@@ -541,7 +541,7 @@ static void packet_handler(int                  fd,
                 pthread_mutex_unlock(&dt.stat[dt_pci.eid].lock);
 #endif
                 dt.comps[dt_pci.eid].post_packet(dt.comps[dt_pci.eid].comp,
-                                                 sdb);
+                                                 spb);
         }
 }
 
@@ -758,7 +758,7 @@ void dt_stop(void)
 }
 
 int dt_reg_comp(void * comp,
-                void (* func)(void * func, struct shm_du_buff *),
+                void (* func)(void * func, struct ssm_pk_buff *),
                 char * name)
 {
         int eid;
@@ -809,7 +809,7 @@ void dt_unreg_comp(int eid)
 int dt_write_packet(uint64_t             dst_addr,
                     qoscube_t            qc,
                     uint64_t             eid,
-                    struct shm_du_buff * sdb)
+                    struct ssm_pk_buff * spb)
 {
         struct dt_pci dt_pci;
         int           fd;
@@ -817,10 +817,10 @@ int dt_write_packet(uint64_t             dst_addr,
         uint8_t *     head;
         size_t        len;
 
-        assert(sdb);
+        assert(spb);
         assert(dst_addr != dt.addr);
 
-        len = shm_du_buff_len(sdb);
+        len = ssm_pk_buff_len(spb);
 
 #ifdef IPCP_FLOW_STATS
         if (eid < PROG_RES_FDS) {
@@ -849,13 +849,13 @@ int dt_write_packet(uint64_t             dst_addr,
                 return -EPERM;
         }
 
-        head = shm_du_buff_head_alloc(sdb, dt_pci_info.head_size);
+        head = ssm_pk_buff_head_alloc(spb, dt_pci_info.head_size);
         if (head == NULL) {
                 log_dbg("Failed to allocate DT header.");
                 goto fail_write;
         }
 
-        len = shm_du_buff_len(sdb);
+        len = ssm_pk_buff_len(spb);
 
         dt_pci.dst_addr = dst_addr;
         dt_pci.qc       = qc;
@@ -866,7 +866,7 @@ int dt_write_packet(uint64_t             dst_addr,
 
         dt_pci_ser(head, &dt_pci);
 
-        ret = ipcp_flow_write(fd, sdb);
+        ret = ipcp_flow_write(fd, spb);
         if (ret < 0) {
                 log_dbg("Failed to write packet to fd %d.", fd);
                 if (ret == -EFLOWDOWN)
diff --git a/src/ipcpd/unicast/dt.h b/src/ipcpd/unicast/dt.h
index 2c5b7978..2e713700 100644
--- a/src/ipcpd/unicast/dt.h
+++ b/src/ipcpd/unicast/dt.h
@@ -25,7 +25,7 @@
 
 #include <ouroboros/ipcp.h>
 #include <ouroboros/qoscube.h>
-#include <ouroboros/shm_rdrbuff.h>
+#include <ouroboros/ssm_pool.h>
 
 #define DT_COMP      "Data Transfer"
 #define DT_PROTO     "dtp"
@@ -40,7 +40,7 @@ int  dt_start(void);
 void dt_stop(void);
 
 int  dt_reg_comp(void *  comp,
-                 void (* func)(void * comp, struct shm_du_buff * sdb),
+                 void (* func)(void * comp, struct ssm_pk_buff * spb),
                  char *  name);
 
 void dt_unreg_comp(int eid);
@@ -48,6 +48,6 @@ void dt_unreg_comp(int eid);
 int  dt_write_packet(uint64_t             dst_addr,
                      qoscube_t            qc,
                      uint64_t             eid,
-                     struct shm_du_buff * sdb);
+                     struct ssm_pk_buff * spb);
 
 #endif /* OUROBOROS_IPCPD_UNICAST_DT_H */
diff --git a/src/ipcpd/unicast/fa.c b/src/ipcpd/unicast/fa.c
index dc23340c..06e4b043 100644
--- a/src/ipcpd/unicast/fa.c
+++ b/src/ipcpd/unicast/fa.c
@@ -85,7 +85,7 @@ struct fa_msg {
 
 struct cmd {
         struct list_head     next;
-        struct shm_du_buff * sdb;
+        struct ssm_pk_buff * spb;
 };
 
 struct fa_flow {
@@ -330,7 +330,7 @@ static uint64_t gen_eid(int fd)
 
 static void packet_handler(int                  fd,
                            qoscube_t            qc,
-                           struct shm_du_buff * sdb)
+                           struct ssm_pk_buff * spb)
 {
         struct fa_flow * flow;
         uint64_t         r_addr;
@@ -342,7 +342,7 @@ static void packet_handler(int                  fd,
 
         pthread_rwlock_wrlock(&fa.flows_lock);
 
-        len = shm_du_buff_len(sdb);
+        len = ssm_pk_buff_len(spb);
 
 #ifdef IPCP_FLOW_STATS
         ++flow->p_snd;
@@ -357,8 +357,8 @@ static void packet_handler(int                  fd,
 
         ca_wnd_wait(wnd);
 
-        if (dt_write_packet(r_addr, qc, r_eid, sdb)) {
-                ipcp_sdb_release(sdb);
+        if (dt_write_packet(r_addr, qc, r_eid, spb)) {
+                ipcp_spb_release(spb);
                 log_dbg("Failed to forward packet.");
 #ifdef IPCP_FLOW_STATS
                 pthread_rwlock_wrlock(&fa.flows_lock);
@@ -411,7 +411,7 @@ static void fa_flow_fini(struct fa_flow * flow)
 }
 
 static void fa_post_packet(void *               comp,
-                           struct shm_du_buff * sdb)
+                           struct ssm_pk_buff * spb)
 {
         struct cmd * cmd;
 
@@ -422,11 +422,11 @@ static void fa_post_packet(void *               comp,
         cmd = malloc(sizeof(*cmd));
         if (cmd == NULL) {
                 log_err("Command failed. Out of memory.");
-                ipcp_sdb_release(sdb);
+                ipcp_spb_release(spb);
                 return;
         }
 
-        cmd->sdb = sdb;
+        cmd->spb = spb;
 
         pthread_mutex_lock(&fa.mtx);
 
@@ -454,16 +454,16 @@ static size_t fa_wait_for_fa_msg(struct fa_msg * msg)
 
         pthread_cleanup_pop(true);
 
-        len = shm_du_buff_len(cmd->sdb);
+        len = ssm_pk_buff_len(cmd->spb);
         if (len > MSGBUFSZ || len < sizeof(*msg)) {
                 log_warn("Invalid flow allocation message (len: %zd).", len);
                 free(cmd);
                 return 0; /* No valid message */
         }
 
-        memcpy(msg, shm_du_buff_head(cmd->sdb), len);
+        memcpy(msg, ssm_pk_buff_head(cmd->spb), len);
 
-        ipcp_sdb_release(cmd->sdb);
+        ipcp_spb_release(cmd->spb);
 
         free(cmd);
 
@@ -753,7 +753,7 @@ int fa_alloc(int              fd,
              const buffer_t * data)
 {
         struct fa_msg *      msg;
-        struct shm_du_buff * sdb;
+        struct ssm_pk_buff * spb;
         struct fa_flow *     flow;
         uint64_t             addr;
         qoscube_t            qc = QOS_CUBE_BE;
@@ -766,10 +766,10 @@ int fa_alloc(int              fd,
 
         len = sizeof(*msg) + ipcp_dir_hash_len();
 
-        if (ipcp_sdb_reserve(&sdb, len + data->len))
+        if (ipcp_spb_reserve(&spb, len + data->len))
                 return -1;
 
-        msg = (struct fa_msg *) shm_du_buff_head(sdb);
+        msg = (struct fa_msg *) ssm_pk_buff_head(spb);
         memset(msg, 0, sizeof(*msg));
 
         eid = gen_eid(fd);
@@ -788,11 +788,11 @@ int fa_alloc(int              fd,
 
         memcpy(msg + 1, dst, ipcp_dir_hash_len());
         if (data->len > 0)
-                memcpy(shm_du_buff_head(sdb) + len, data->data, data->len);
+                memcpy(ssm_pk_buff_head(spb) + len, data->data, data->len);
 
-        if (dt_write_packet(addr, qc, fa.eid, sdb)) {
+        if (dt_write_packet(addr, qc, fa.eid, spb)) {
                 log_err("Failed to send flow allocation request packet.");
-                ipcp_sdb_release(sdb);
+                ipcp_spb_release(spb);
                 return -1;
         }
 
@@ -814,7 +814,7 @@ int fa_alloc_resp(int              fd,
                   const buffer_t * data)
 {
         struct fa_msg *      msg;
-        struct shm_du_buff * sdb;
+        struct ssm_pk_buff * spb;
         struct fa_flow *     flow;
         qoscube_t            qc = QOS_CUBE_BE;
 
@@ -825,13 +825,13 @@ int fa_alloc_resp(int              fd,
                 goto fail_alloc_resp;
         }
 
-        if (ipcp_sdb_reserve(&sdb, sizeof(*msg) + data->len)) {
-                log_err("Failed to reserve sdb (%zu  bytes).",
+        if (ipcp_spb_reserve(&spb, sizeof(*msg) + data->len)) {
+                log_err("Failed to reserve spb (%zu  bytes).",
                         sizeof(*msg) + data->len);
                 goto fail_reserve;
         }
 
-        msg = (struct fa_msg *) shm_du_buff_head(sdb);
+        msg = (struct fa_msg *) ssm_pk_buff_head(spb);
         memset(msg, 0, sizeof(*msg));
 
         msg->code     = FLOW_REPLY;
@@ -846,7 +846,7 @@ int fa_alloc_resp(int              fd,
 
         pthread_rwlock_unlock(&fa.flows_lock);
 
-        if (dt_write_packet(flow->r_addr, qc, fa.eid, sdb)) {
+        if (dt_write_packet(flow->r_addr, qc, fa.eid, spb)) {
                 log_err("Failed to send flow allocation response packet.");
                 goto fail_packet;
         }
@@ -862,7 +862,7 @@ int fa_alloc_resp(int              fd,
         return 0;
 
  fail_packet:
-        ipcp_sdb_release(sdb);
+        ipcp_spb_release(spb);
  fail_reserve:
         pthread_rwlock_wrlock(&fa.flows_lock);
         fa_flow_fini(flow);
@@ -893,17 +893,17 @@ static int fa_update_remote(int      fd,
                             uint16_t ece)
 {
         struct fa_msg *      msg;
-        struct shm_du_buff * sdb;
+        struct ssm_pk_buff * spb;
         qoscube_t            qc = QOS_CUBE_BE;
         struct fa_flow *     flow;
         uint64_t             r_addr;
 
-        if (ipcp_sdb_reserve(&sdb, sizeof(*msg))) {
-                log_err("Failed to reserve sdb (%zu  bytes).", sizeof(*msg));
+        if (ipcp_spb_reserve(&spb, sizeof(*msg))) {
+                log_err("Failed to reserve spb (%zu  bytes).", sizeof(*msg));
                 return -1;
         }
 
-        msg = (struct fa_msg *) shm_du_buff_head(sdb);
+        msg = (struct fa_msg *) ssm_pk_buff_head(spb);
 
         memset(msg, 0, sizeof(*msg));
 
@@ -922,9 +922,9 @@ static int fa_update_remote(int      fd,
         pthread_rwlock_unlock(&fa.flows_lock);
 
 
-        if (dt_write_packet(r_addr, qc, fa.eid, sdb)) {
+        if (dt_write_packet(r_addr, qc, fa.eid, spb)) {
                 log_err("Failed to send flow update packet.");
-                ipcp_sdb_release(sdb);
+                ipcp_spb_release(spb);
                 return -1;
         }
 
@@ -933,7 +933,7 @@ static int fa_update_remote(int      fd,
 
 void  fa_np1_rcv(uint64_t             eid,
                  uint8_t              ecn,
-                 struct shm_du_buff * sdb)
+                 struct ssm_pk_buff * spb)
 {
         struct fa_flow * flow;
         bool             update;
@@ -941,7 +941,7 @@ void  fa_np1_rcv(uint64_t             eid,
         int              fd;
         size_t           len;
 
-        len = shm_du_buff_len(sdb);
+        len = ssm_pk_buff_len(spb);
 
         pthread_rwlock_wrlock(&fa.flows_lock);
 
@@ -949,7 +949,7 @@ void  fa_np1_rcv(uint64_t             eid,
         if (fd < 0) {
                 pthread_rwlock_unlock(&fa.flows_lock);
                 log_dbg("Received packet for unknown EID %" PRIu64 ".", eid);
-                ipcp_sdb_release(sdb);
+                ipcp_spb_release(spb);
                 return;
         }
 
@@ -963,9 +963,9 @@ void  fa_np1_rcv(uint64_t             eid,
 
         pthread_rwlock_unlock(&fa.flows_lock);
 
-        if (ipcp_flow_write(fd, sdb) < 0) {
+        if (ipcp_flow_write(fd, spb) < 0) {
                 log_dbg("Failed to write to flow %d.", fd);
-                ipcp_sdb_release(sdb);
+                ipcp_spb_release(spb);
 #ifdef IPCP_FLOW_STATS
                 pthread_rwlock_wrlock(&fa.flows_lock);
                 ++flow->p_rcv_f;
diff --git a/src/ipcpd/unicast/fa.h b/src/ipcpd/unicast/fa.h
index 1e716966..6cd30995 100644
--- a/src/ipcpd/unicast/fa.h
+++ b/src/ipcpd/unicast/fa.h
@@ -47,6 +47,6 @@ int  fa_dealloc(int fd);
 
 void fa_np1_rcv(uint64_t             eid,
                 uint8_t              ecn,
-                struct shm_du_buff * sdb);
+                struct ssm_pk_buff * spb);
 
 #endif /* OUROBOROS_IPCPD_UNICAST_FA_H */
diff --git a/src/ipcpd/unicast/psched.c b/src/ipcpd/unicast/psched.c
index f74b4065..8c8caf19 100644
--- a/src/ipcpd/unicast/psched.c
+++ b/src/ipcpd/unicast/psched.c
@@ -69,7 +69,7 @@ static void cleanup_reader(void * o)
 static void * packet_reader(void * o)
 {
         struct psched *       sched;
-        struct shm_du_buff *  sdb;
+        struct ssm_pk_buff *  spb;
         int                   fd;
         fqueue_t *            fq;
         qoscube_t             qc;
@@ -104,10 +104,10 @@ static void * packet_reader(void * o)
                                 notifier_event(NOTIFY_DT_FLOW_UP, &fd);
                                 break;
                         case FLOW_PKT:
-                                if (sched->read(fd, &sdb) < 0)
+                                if (sched->read(fd, &spb) < 0)
                                         continue;
 
-                                sched->callback(fd, qc, sdb);
+                                sched->callback(fd, qc, spb);
                                 break;
                         default:
                                 break;
diff --git a/src/ipcpd/unicast/psched.h b/src/ipcpd/unicast/psched.h
index 831f8084..be9c09e3 100644
--- a/src/ipcpd/unicast/psched.h
+++ b/src/ipcpd/unicast/psched.h
@@ -28,10 +28,10 @@
 
 typedef void (* next_packet_fn_t)(int                  fd,
                                   qoscube_t            qc,
-                                  struct shm_du_buff * sdb);
+                                  struct ssm_pk_buff * spb);
 
 typedef int (* read_fn_t)(int                   fd,
-                          struct shm_du_buff ** sdb);
+                          struct ssm_pk_buff ** spb);
 
 struct psched * psched_create(next_packet_fn_t callback,
                               read_fn_t        read);
diff --git a/src/ipcpd/unicast/routing/link-state.c b/src/ipcpd/unicast/routing/link-state.c
index e5edf539..95a104bb 100644
--- a/src/ipcpd/unicast/routing/link-state.c
+++ b/src/ipcpd/unicast/routing/link-state.c
@@ -56,7 +56,7 @@
 #include <string.h>
 
 #define LS_ENTRY_SIZE  104
-#define LSDB           "lsdb"
+#define Lspb           "lspb"
 
 #ifndef CLOCK_REALTIME_COARSE
 #define CLOCK_REALTIME_COARSE CLOCK_REALTIME
@@ -199,7 +199,7 @@ static struct adjacency * get_adj(const char * path)
         return NULL;
 }
 
-static int lsdb_rib_getattr(const char *      path,
+static int lspb_rib_getattr(const char *      path,
                             struct rib_attr * attr)
 {
         struct adjacency * adj;
@@ -230,7 +230,7 @@ static int lsdb_rib_getattr(const char *      path,
         return 0;
 }
 
-static int lsdb_rib_read(const char * path,
+static int lspb_rib_read(const char * path,
                          char *       buf,
                          size_t       len)
 {
@@ -264,7 +264,7 @@ static int lsdb_rib_read(const char * path,
         return -1;
 }
 
-static int lsdb_rib_readdir(char *** buf)
+static int lspb_rib_readdir(char *** buf)
 {
         struct list_head * p;
         char               entry[RIB_PATH_LEN + 1];
@@ -319,12 +319,12 @@ static int lsdb_rib_readdir(char *** buf)
 }
 
 static struct rib_ops r_ops = {
-        .read    = lsdb_rib_read,
-        .readdir = lsdb_rib_readdir,
-        .getattr = lsdb_rib_getattr
+        .read    = lspb_rib_read,
+        .readdir = lspb_rib_readdir,
+        .getattr = lspb_rib_getattr
 };
 
-static int lsdb_add_nb(uint64_t     addr,
+static int lspb_add_nb(uint64_t     addr,
                        int          fd,
                        enum nb_type type)
 {
@@ -372,7 +372,7 @@ static int lsdb_add_nb(uint64_t     addr,
         return 0;
 }
 
-static int lsdb_del_nb(uint64_t addr,
+static int lspb_del_nb(uint64_t addr,
                        int      fd)
 {
         struct list_head * p;
@@ -478,7 +478,7 @@ static void set_pff_modified(bool calc)
         pthread_mutex_unlock(&ls.instances.mtx);
 }
 
-static int lsdb_add_link(uint64_t    src,
+static int lspb_add_link(uint64_t    src,
                          uint64_t    dst,
                          uint64_t    seqno,
                          qosspec_t * qs)
@@ -535,7 +535,7 @@ static int lsdb_add_link(uint64_t    src,
         return 0;
 }
 
-static int lsdb_del_link(uint64_t src,
+static int lspb_del_link(uint64_t src,
                          uint64_t dst)
 {
         struct list_head * p;
@@ -616,8 +616,8 @@ static void send_lsm(uint64_t src,
         }
 }
 
-/* replicate the lsdb to a mgmt neighbor */
-static void lsdb_replicate(int fd)
+/* replicate the lspb to a mgmt neighbor */
+static void lspb_replicate(int fd)
 {
         struct list_head * p;
         struct list_head * h;
@@ -625,7 +625,7 @@ static void lsdb_replicate(int fd)
 
         list_head_init(&copy);
 
-        /* Lock the lsdb, copy the lsms and send outside of lock. */
+        /* Lock the lspb, copy the lsms and send outside of lock. */
         pthread_rwlock_rdlock(&ls.lock);
 
         list_for_each(p, &ls.db.list) {
@@ -634,7 +634,7 @@ static void lsdb_replicate(int fd)
                 adj = list_entry(p, struct adjacency, next);
                 cpy = malloc(sizeof(*cpy));
                 if (cpy == NULL) {
-                        log_warn("Failed to replicate full lsdb.");
+                        log_warn("Failed to replicate full lspb.");
                         break;
                 }
 
@@ -814,7 +814,7 @@ static void * lsreader(void * o)
                                   LSU_VAL(msg.s_addr, msg.d_addr, msg.seqno),
                                   ADDR_VAL32(&ls.addr));
 #endif
-                        if (lsdb_add_link(msg.s_addr,
+                        if (lspb_add_link(msg.s_addr,
                                           msg.d_addr,
                                           msg.seqno,
                                           &qs))
@@ -873,20 +873,20 @@ static void handle_event(void *       self,
                 send_lsm(ls.addr, c->conn_info.addr, 0);
                 pthread_cleanup_pop(true);
 
-                if (lsdb_add_nb(c->conn_info.addr, c->flow_info.fd, NB_DT))
-                        log_dbg("Failed to add neighbor to LSDB.");
+                if (lspb_add_nb(c->conn_info.addr, c->flow_info.fd, NB_DT))
+                        log_dbg("Failed to add neighbor to Lspb.");
 
-                if (lsdb_add_link(ls.addr, c->conn_info.addr, 0, &qs))
-                        log_dbg("Failed to add new adjacency to LSDB.");
+                if (lspb_add_link(ls.addr, c->conn_info.addr, 0, &qs))
+                        log_dbg("Failed to add new adjacency to Lspb.");
                 break;
         case NOTIFY_DT_CONN_DEL:
                 flow_event(c->flow_info.fd, false);
 
-                if (lsdb_del_nb(c->conn_info.addr, c->flow_info.fd))
-                        log_dbg("Failed to delete neighbor from LSDB.");
+                if (lspb_del_nb(c->conn_info.addr, c->flow_info.fd))
+                        log_dbg("Failed to delete neighbor from Lspb.");
 
-                if (lsdb_del_link(ls.addr, c->conn_info.addr))
-                        log_dbg("Local link was not in LSDB.");
+                if (lspb_del_link(ls.addr, c->conn_info.addr))
+                        log_dbg("Local link was not in Lspb.");
                 break;
         case NOTIFY_DT_CONN_QOS:
                 log_dbg("QoS changes currently unsupported.");
@@ -901,15 +901,15 @@ static void handle_event(void *       self,
                 fccntl(c->flow_info.fd, FLOWGFLAGS, &flags);
                 fccntl(c->flow_info.fd, FLOWSFLAGS, flags | FLOWFRNOPART);
                 fset_add(ls.mgmt_set, c->flow_info.fd);
-                if (lsdb_add_nb(c->conn_info.addr, c->flow_info.fd, NB_MGMT))
-                        log_warn("Failed to add mgmt neighbor to LSDB.");
-                /* replicate the entire lsdb */
-                lsdb_replicate(c->flow_info.fd);
+                if (lspb_add_nb(c->conn_info.addr, c->flow_info.fd, NB_MGMT))
+                        log_warn("Failed to add mgmt neighbor to Lspb.");
+                /* replicate the entire lspb */
+                lspb_replicate(c->flow_info.fd);
                 break;
         case NOTIFY_MGMT_CONN_DEL:
                 fset_del(ls.mgmt_set, c->flow_info.fd);
-                if (lsdb_del_nb(c->conn_info.addr, c->flow_info.fd))
-                        log_warn("Failed to delete mgmt neighbor from LSDB.");
+                if (lspb_del_nb(c->conn_info.addr, c->flow_info.fd))
+                        log_warn("Failed to delete mgmt neighbor from Lspb.");
                 break;
         default:
                 break;
@@ -1094,7 +1094,7 @@ int link_state_init(struct ls_config * conf,
         list_head_init(&ls.nbs.list);
         list_head_init(&ls.instances.list);
 
-        if (rib_reg(LSDB, &r_ops))
+        if (rib_reg(Lspb, &r_ops))
                 goto fail_rib_reg;
 
         ls.db.len  = 0;
@@ -1121,7 +1121,7 @@ void link_state_fini(void)
         struct list_head * p;
         struct list_head * h;
 
-        rib_unreg(LSDB);
+        rib_unreg(Lspb);
 
         fset_destroy(ls.mgmt_set);