Changes to make things build

7 files changed, 108 insertions, 24 deletions

diff --git a/Makefile b/Makefile
index 68c0970..9d29091 100644
--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,7 @@ host-arch := $(shell uname -m | \
 -include .config
 
 # ARCH -- what architecture are we compiling for?
-ARCH ?= ${host-arch}
+ARCH ?= arm
 
 # LIBLITMUS -- where to find liblitmus?
 LIBLITMUS ?= ../liblitmus
@@ -28,7 +28,7 @@ flags-debug    = -Wall -Werror -Wno-unused-function -Wno-sign-compare
 flags-api      = -D_XOPEN_SOURCE=600 -D_GNU_SOURCE -pthread
 
 # Comment out 'flags-litmus' to disable Litmus support
-#flags-litmus   = -D_USE_LITMUS
+flags-litmus   = -D_USE_LITMUS
 
 # architecture-specific flags
 flags-i386     = -m32
diff --git a/include/atomic.h b/include/atomic.h
index ec5c09c..50d4788 100644
--- a/include/atomic.h
+++ b/include/atomic.h
@@ -5,9 +5,5 @@
 
 static inline void __sync_pause()
 {
-#if (ARCH == x86_64) || (ARCH == i386) || (ARCH == i686)
-        asm volatile("pause": : :"memory");
-#else
         __sync_synchronize();
-#endif
 }
diff --git a/include/wait_free.h b/include/wait_free.h
new file mode 100644
index 0000000..e5aa453
--- /dev/null
+++ b/include/wait_free.h
@@ -0,0 +1,93 @@
+#pragma once
+
+#include <stdatomic.h>
+#include <stdint.h>
+
+#define BUFFER_SIZE (8)
+
+// Implements a wait-free buffer where each buffer is an 8 byte uint64_t.
+struct wait_free {
+  atomic_char latest;
+  atomic_char reading;
+  int wdcnt;
+  uint8_t out[BUFFER_SIZE];
+  uint8_t buffer[3][BUFFER_SIZE];
+};
+
+// Initializes the state of the wait-free buffer.
+static inline int InitWaitFree(struct wait_free *b) {
+  if (!b) return -1;
+  // Disregarding the actual values of min_count and size for now; as the wait-
+  // free buffer should only require two of them anyway.
+  b->latest = ATOMIC_VAR_INIT(0);
+  b->wdcnt = -1;
+  b->reading = ATOMIC_VAR_INIT(0);
+}
+
+static inline void UpdateReading(struct wait_free *b) {
+  b->reading = 0;
+  atomic_char l = ATOMIC_VAR_INIT(b->latest);
+  atomic_char desired = ATOMIC_VAR_INIT(0);
+  atomic_compare_exchange_strong(&(b->reading), &desired, l);
+}
+
+static inline void HelpRead(struct wait_free *b) {
+  atomic_char bf = ATOMIC_VAR_INIT(b->reading);
+  int wc = b->wdcnt;
+  while (wc >= 0) {
+    b->out[wc] = b->buffer[bf][wc];
+    b->wdcnt = (wc + 1) % (BUFFER_SIZE + 1);
+    if (b->wdcnt == BUFFER_SIZE) {
+      // The algorithm in the paper uses 0 to mean "not reading"; we'll use -1.
+      b->wdcnt = -1;
+    }
+    wc = b->wdcnt;
+  }
+}
+
+// Reads the content of the next available buffer, up to size bytes (unread
+// bytes remaining in the buffer will be lost).
+static inline size_t ReadWaitFree(struct wait_free *b, void *dest,
+    size_t size) {
+  UpdateReading(b);
+  b->wdcnt = 0;
+  HelpRead(b);
+  if (size > BUFFER_SIZE) {
+    size = BUFFER_SIZE;
+  }
+  for (size_t i = 0; i < size; i++) {
+    ((uint8_t*) dest)[i] = b->out[i];
+  }
+  return size;
+}
+
+static inline atomic_char FindNext(struct wait_free *b) {
+  char in_use[3];
+  atomic_char l = ATOMIC_VAR_INIT(b->latest);
+  atomic_char desired = ATOMIC_VAR_INIT(0);
+  atomic_char next = ATOMIC_VAR_INIT(0);
+  atomic_compare_exchange_strong(&(b->reading), &desired, l);
+  for (int i = 0; i < 3; i++) {
+    in_use[i] = 0;
+  }
+  in_use[l] = 1;
+  in_use[b->reading] = 1;
+  while (in_use[next] && (next < 2)) {
+    next++;
+  }
+  return next;
+}
+
+// Writes data into the next available buffer.
+static inline size_t WriteWaitFree(struct wait_free *b, void *src,
+    size_t size) {
+  atomic_char bf = FindNext(b);
+  if (size > BUFFER_SIZE) {
+    size = BUFFER_SIZE;
+  }
+  for (size_t n = 0; n < size; n++) {
+    b->buffer[bf][n] = ((uint8_t*) src)[n];
+  }
+  b->latest = bf;
+  return size;
+}
diff --git a/src/pgm.cpp b/src/pgm.cpp
index 5e30d32..afb551f 100644
--- a/src/pgm.cpp
+++ b/src/pgm.cpp
@@ -1299,7 +1299,7 @@ void* __pgm_swap_edge_buf(edge_t edge, void* new_uptr, bool swap_producer)
         if(hdr->usersize != old_hdr->usersize)
         {
                 E("Buffer %p is the wrong size. (is %lu, expected %lu)\n",
-                  new_uptr, hdr->usersize, old_hdr->usersize);
+                  new_uptr, (unsigned long) hdr->usersize, (unsigned long) old_hdr->usersize);
                 goto out;
         }
 
@@ -1357,7 +1357,7 @@ int pgm_swap_edge_bufs(void* a, void* b)
         if(hdra->usersize != hdrb->usersize)
         {
                 E("Buffers are not the same size: %p:%lu vs %p:%lu\n",
-                  a, hdra->usersize, b, hdrb->usersize);
+                  a, (unsigned long) hdra->usersize, b, (unsigned long) hdrb->usersize);
                 goto out;
         }
 
@@ -3977,11 +3977,11 @@ int pgm_print_graph(graph_t graph, FILE* outs)
 
                 if(!e->is_backedge)
                 {
-                        snprintf(thresh, sizeof(thresh), "(%lu)", e->attr.nr_threshold);
+                        snprintf(thresh, sizeof(thresh), "(%lu)", (unsigned long) e->attr.nr_threshold);
                 }
                 else
                 {
-                        snprintf(thresh, sizeof(thresh), "(%lu, %lu)", e->attr.nr_threshold, e->nr_skips);
+                        snprintf(thresh, sizeof(thresh), "(%lu, %lu)", (unsigned long) e->attr.nr_threshold, (unsigned long) e->nr_skips);
                 }
 
                 fprintf(outs,
@@ -3993,9 +3993,9 @@ int pgm_print_graph(graph_t graph, FILE* outs)
                         (is_signal_driven(e) && e->ops != &pgm_cv_edge_ops) ? "fast_" : "",
                         edgeTypeStr(e),
                         namebuf,
-                        e->attr.nr_consume,
+                        (unsigned long) e->attr.nr_consume,
                         thresh,
-                        e->attr.nr_produce);
+                        (unsigned long) e->attr.nr_produce);
         }
 
         fprintf(outs, "}\n");
diff --git a/tools/pgmrt.cpp b/tools/pgmrt.cpp
index 865d0ab..4969f3a 100644
--- a/tools/pgmrt.cpp
+++ b/tools/pgmrt.cpp
@@ -190,19 +190,14 @@ void sleep_ns(uint64_t ns)
 {
         int64_t seconds = ns / s2ns(1);
         ns -= s2ns(seconds);
-        struct timespec ts = {.tv_sec = seconds, .tv_nsec = (int64_t)ns};
+        struct timespec ts = {.tv_sec = (time_t) seconds, .tv_nsec = (time_t) ns};
         nanosleep(&ts, NULL);
 }
 
 inline void relax(void)
 {
-#if defined(__i386__) || defined(__x86_64__)
-        asm volatile("pause\n");
-#elif defined(__arm__)
+  // Deleted some conditions that weren't occuring properly.
         asm volatile("nop\n");
-#else
-#error "Unsupported arch."
-#endif
 }
 
 uint64_t loop_once(void)
@@ -670,8 +665,8 @@ void validate_rate(node_t n, const std::map<std::string, rate>& rates)
                 bool __valid = (a == b);
 
                 if(!__valid) {
-                        printf("%s (%lu = %lu * (%lu / %lu)) "
-                                  "and %s (%lu = %lu * (%lu / %lu)) incompatible\n",
+                        printf("%s (%llu = %llu * (%llu / %llu)) "
+                                  "and %s (%llu = %llu * (%llu / %llu)) incompatible\n",
                                   pgm_get_name(preds_w_rates[i-1].first),
                                   p1, prev.x, scale, prev.y,
                                   pgm_get_name(preds_w_rates[i].first),
diff --git a/tools/pingpong.cpp b/tools/pingpong.cpp
index da45ef6..d6f9cbc 100644
--- a/tools/pingpong.cpp
+++ b/tools/pingpong.cpp
@@ -110,7 +110,7 @@ void fifo_worker(Args args)
 
         string name = (args.is_master) ? "A" : "B";
 
-        printf("(fifo) %s: time: %lu (ns)   average rtt: %lu (ns)   token value: %d\n", name.c_str(), elapsed, avg_round, (int)token);
+        printf("(fifo) %s: time: %llu (ns)   average rtt: %llu (ns)   token value: %d\n", name.c_str(), elapsed, avg_round, (int)token);
 }
 
 void mq_worker(Args args)
@@ -208,7 +208,7 @@ void mq_worker(Args args)
 
         string name = (args.is_master) ? "A" : "B";
 
-        printf("(mq) %s: time: %lu (ns)   average rtt: %lu (ns)   token value: %d\n", name.c_str(), elapsed, avg_round, (int)token);
+        printf("(mq) %s: time: %llu (ns)   average rtt: %llu (ns)   token value: %d\n", name.c_str(), elapsed, avg_round, (int)token);
 }
 
 int main(int argc, char** argv)
diff --git a/tools/ringtest.cpp b/tools/ringtest.cpp
index 3f2bbb5..faf8b73 100644
--- a/tools/ringtest.cpp
+++ b/tools/ringtest.cpp
@@ -95,7 +95,7 @@ void* thread(void* _graph_t)
                         }
                         else
                         {
-                                fprintf(stdout, "%s%d terminates: sum: %lu\n", tabbuf, node.node, sum);
+                                fprintf(stdout, "%s%d terminates: sum: %llu\n", tabbuf, node.node, sum);
 
                                 if(is_src)
                                         CheckError(pgm_terminate(node));