communicate downstream buffer reqs to upstream output allocator

8 files changed, 97 insertions, 11 deletions

diff --git a/lib/block_allocator.cpp b/lib/block_allocator.cpp
index 22f60af..5f45dd0 100644
--- a/lib/block_allocator.cpp
+++ b/lib/block_allocator.cpp
@@ -15,13 +15,18 @@
 // along with io_sig program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include "element_impl.hpp"
-#include <gras_impl/messages.hpp>
 #include <boost/bind.hpp>
+#include <boost/foreach.hpp>
+#include <boost/math/common_factor.hpp>
 
 using namespace gnuradio;
 
-//TODO will need more complicated later
+const size_t AT_LEAST_DEFAULT_ITEMS = 1024*2;
+const size_t AHH_TOO_MANY_BYTES = 1 << 16; //TODO
+const size_t THIS_MANY_BUFFERS = 8;
+const double EDGE_CASE_MITIGATION = 8.0; //edge case mitigation constant
 
+//TODO will need more complicated later
 
 void ElementImpl::buffer_returner(const size_t index, SBuffer &buffer)
 {
@@ -35,6 +40,35 @@ void ElementImpl::buffer_returner(const size_t index, SBuffer &buffer)
     this->block.post_msg(message);
 }
 
+static size_t recommend_length(
+    const std::vector<BufferHintMessage> &hints,
+    const size_t output_multiple_bytes,
+    const size_t at_least_bytes
+){
+    //step 1) find the LCM of all reserves to create a super-reserve
+    size_t lcm_bytes = output_multiple_bytes;
+    BOOST_FOREACH(const BufferHintMessage &hint, hints)
+    {
+        lcm_bytes = boost::math::lcm(lcm_bytes, hint.reserve_bytes);
+    }
+
+    //step 2) N x super reserve to minimize history edge case
+    size_t Nlcm_bytes = lcm_bytes;
+    BOOST_FOREACH(const BufferHintMessage &hint, hints)
+    {
+        while (hint.history_bytes*EDGE_CASE_MITIGATION > Nlcm_bytes)
+        {
+            Nlcm_bytes += lcm_bytes;
+        }
+    }
+    while (at_least_bytes > Nlcm_bytes)
+    {
+        Nlcm_bytes += lcm_bytes;
+    }
+
+    return std::min(Nlcm_bytes, AHH_TOO_MANY_BYTES);
+}
+
 void ElementImpl::handle_allocation(const tsbe::TaskInterface &task_iface)
 {
     //allocate output buffers which will also wake up the task
@@ -42,16 +76,19 @@ void ElementImpl::handle_allocation(const tsbe::TaskInterface &task_iface)
     this->output_buffer_tokens.resize(num_outputs);
     for (size_t i = 0; i < num_outputs; i++)
     {
-        size_t items = this->hint;
-        if (items == 0) items = 2048;
-        items = std::max(items, this->output_multiple_items[i]);
+        size_t at_least_items = this->hint;
+        if (at_least_items == 0) at_least_items = AT_LEAST_DEFAULT_ITEMS;
 
-        const size_t bytes = items * this->output_items_sizes[i];
+        const size_t bytes = recommend_length(
+            this->output_allocation_hints[i],
+            this->output_multiple_items[i]*this->output_items_sizes[i],
+            at_least_items*this->output_items_sizes[i]
+        );
 
         SBufferDeleter deleter = boost::bind(&ElementImpl::buffer_returner, this, i, _1);
         this->output_buffer_tokens[i] = SBufferToken(new SBufferDeleter(deleter));
 
-        for (size_t j = 0; j < 8; j++)
+        for (size_t j = 0; j < THIS_MANY_BUFFERS; j++)
         {
             SBufferConfig config;
             config.memory = NULL;
diff --git a/lib/block_handlers.cpp b/lib/block_handlers.cpp
index 4ecfa20..3715615 100644
--- a/lib/block_handlers.cpp
+++ b/lib/block_handlers.cpp
@@ -15,7 +15,6 @@
 // along with io_sig program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include "element_impl.hpp"
-#include <gras_impl/messages.hpp>
 #include <gras_impl/vector_utils.hpp>
 #include <boost/make_shared.hpp>
 #include <boost/bind.hpp>
@@ -89,6 +88,15 @@ void ElementImpl::handle_block_msg(
         {
             this->input_tokens[i] = Token::make();
             task_iface.post_upstream(i, this->input_tokens[i]);
+
+            //TODO, schedule this message as a pre-allocation message
+            //tell the upstream about the input requirements
+            BufferHintMessage message;
+            message.history_bytes = this->input_history_items[i]*this->input_items_sizes[i];
+            message.reserve_bytes = input_multiple_items[i];
+            message.token = this->input_tokens[i];
+            task_iface.post_upstream(i, message);
+
         }
         for (size_t i = 0; i < num_outputs; i++)
         {
@@ -164,13 +172,14 @@ void ElementImpl::topology_update(const tsbe::TaskInterface &task_iface)
 
     this->input_tokens.resize(num_inputs);
     this->output_tokens.resize(num_outputs);
+    this->output_allocation_hints.resize(num_outputs);
 
     //resize tags vector to match sizes
     this->input_tags_changed.resize(num_inputs);
     this->input_tags.resize(num_inputs);
 
     //impose input reserve requirements based on relative rate and output multiple
-    std::vector<size_t> input_multiple_items(num_inputs, 1);
+    this->input_multiple_items.resize(num_inputs, 1);
     for (size_t i = 0; i < num_inputs; i++)
     {
         //TODO, this is a little cheap, we only look at output multiple [0]
diff --git a/lib/element_impl.hpp b/lib/element_impl.hpp
index 8cbf2be..44125b1 100644
--- a/lib/element_impl.hpp
+++ b/lib/element_impl.hpp
@@ -19,6 +19,7 @@
 
 #include <gras_impl/debug.hpp>
 #include <gras_impl/token.hpp>
+#include <gras_impl/messages.hpp>
 #include <gras_impl/vector_of_queues.hpp>
 #include <gras_impl/input_buffer_queues.hpp>
 #include <gras_impl/interruptible_thread.hpp>
@@ -65,6 +66,7 @@ struct ElementImpl
     IOSignature output_signature;
     std::vector<size_t> input_history_items;
     std::vector<size_t> output_multiple_items;
+    std::vector<size_t> input_multiple_items;
 
     //keeps track of production
     std::vector<uint64_t> items_consumed;
@@ -148,6 +150,8 @@ struct ElementImpl
     Token token;
     size_t hint; //some kind of allocation hint
 
+    std::vector<std::vector<BufferHintMessage> > output_allocation_hints;
+
     //rate settings
     bool enable_fixed_rate;
     double relative_rate;
diff --git a/lib/gras_impl/interruptible_thread.hpp b/lib/gras_impl/interruptible_thread.hpp
index 1e99111..e7025bf 100644
--- a/lib/gras_impl/interruptible_thread.hpp
+++ b/lib/gras_impl/interruptible_thread.hpp
@@ -91,6 +91,7 @@ namespace gnuradio
                 {
                     while (_wait_msg) _cond.wait(lock);
                     _wait_msg = true;
+                    if (not _callable) break;
                     _callable();
                     _wait_ack = false;
                     _notify(lock);
diff --git a/lib/gras_impl/messages.hpp b/lib/gras_impl/messages.hpp
index d5bfc8b..e1a3565 100644
--- a/lib/gras_impl/messages.hpp
+++ b/lib/gras_impl/messages.hpp
@@ -52,6 +52,12 @@ struct BufferReturnMessage
     SBuffer buffer;
 };
 
+struct BufferHintMessage
+{
+    size_t history_bytes;
+    size_t reserve_bytes;
+    WeakToken token;
+};
 
 } //namespace gnuradio
 
diff --git a/lib/gras_impl/token.hpp b/lib/gras_impl/token.hpp
index 4923f74..d5b438a 100644
--- a/lib/gras_impl/token.hpp
+++ b/lib/gras_impl/token.hpp
@@ -18,10 +18,13 @@
 #define INCLUDED_LIBGRAS_IMPL_TOKEN_HPP
 
 #include <boost/shared_ptr.hpp>
+#include <boost/weak_ptr.hpp>
 
 namespace gnuradio
 {
 
+typedef boost::weak_ptr<int> WeakToken;
+
 struct Token : boost::shared_ptr<int>
 {
     static Token make(void)
diff --git a/lib/port_handlers.cpp b/lib/port_handlers.cpp
index 0b5cfd0..80f8239 100644
--- a/lib/port_handlers.cpp
+++ b/lib/port_handlers.cpp
@@ -15,7 +15,7 @@
 // along with io_sig program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include "element_impl.hpp"
-#include <gras_impl/messages.hpp>
+#include <boost/foreach.hpp>
 
 using namespace gnuradio;
 
@@ -59,6 +59,8 @@ void ElementImpl::handle_input_msg(
         }
         return;
     }
+
+    ASSERT(false);
 }
 
 void ElementImpl::handle_output_msg(
@@ -85,4 +87,29 @@ void ElementImpl::handle_output_msg(
         }
         return;
     }
+
+    //update the buffer allocation hint
+    if (msg.type() == typeid(BufferHintMessage))
+    {
+        //this->output_allocation_hints.resize(std::max(output_allocation_hints.size(), index+1));
+        const BufferHintMessage new_hint = msg.cast<BufferHintMessage>();
+
+        //remove any old hints with expired token
+        //remove any older hints with matching token
+        std::vector<BufferHintMessage> hints;
+        BOOST_FOREACH(const BufferHintMessage &hint, this->output_allocation_hints[index])
+        {
+            if (hint.token.expired()) continue;
+            if (hint.token.lock() == new_hint.token.lock()) continue;
+            hints.push_back(hint);
+        }
+
+        //store the new hint as well
+        hints.push_back(new_hint);
+
+        this->output_allocation_hints[index] = hints;
+        return;
+    }
+
+    ASSERT(false);
 }
diff --git a/lib/top_block.cpp b/lib/top_block.cpp
index 0adcdb0..f3e1fc8 100644
--- a/lib/top_block.cpp
+++ b/lib/top_block.cpp
@@ -15,7 +15,6 @@
 // along with io_sig program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include "element_impl.hpp"
-#include <gras_impl/messages.hpp>
 #include <gnuradio/top_block.hpp>
 #include <boost/thread/thread.hpp> //sleep