import java.util.Objects;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.CompletionStage;
+
import io.fd.vpp.jvpp.JVpp;
import io.fd.vpp.jvpp.JVppRegistry;
import io.fd.vpp.jvpp.VppInvocationException;
@Override
@SuppressWarnings("unchecked")
public <REQ extends JVppRequest, REPLY extends JVppReply<REQ>> CompletionStage<REPLY> send(REQ req) {
- synchronized(requests) {
- try {
- final CompletableFuture<REPLY> replyCompletableFuture;
- final int contextId = jvpp.send(req);
+ try {
+ // jvpp.send() can go to waiting state if sending queue is full, putting it into same
+ // synchronization block as used by receiving part (synchronized(requests)) can lead
+ // to deadlock between these two sides or at least slowing sending process by slow
+ // reader
+ final CompletableFuture<REPLY> replyCompletableFuture;
+ final int contextId = jvpp.send(req);
+
+ if(req instanceof JVppDump) {
+ throw new IllegalArgumentException("Send with empty reply dump has to be used in case of dump calls");
+ }
- if(req instanceof JVppDump) {
- throw new IllegalArgumentException("Send with empty reply dump has to be used in case of dump calls");
+ synchronized(requests) {
+ CompletableFuture<? extends JVppReply<?>> replyFuture = requests.get(contextId);
+ if (replyFuture == null) {
+ // reply not yet received, put new future into map
+ replyCompletableFuture = new CompletableFuture<>();
+ requests.put(contextId, replyCompletableFuture);
+ } else {
+ // reply already received (should be completed by reader),
+ // remove future from map and return it to caller
+ replyCompletableFuture = (CompletableFuture<REPLY>) replyFuture;
+ requests.remove(contextId);
}
- replyCompletableFuture = new CompletableFuture<>();
- requests.put(contextId, replyCompletableFuture);
-
- // TODO in case of timeouts/missing replies, requests from the map are not removed
- // consider adding cancel method, that would remove requests from the map and cancel
- // associated replyCompletableFuture
-
- return replyCompletableFuture;
- } catch (VppInvocationException ex) {
- final CompletableFuture<REPLY> replyCompletableFuture = new CompletableFuture<>();
- replyCompletableFuture.completeExceptionally(ex);
- return replyCompletableFuture;
}
+
+ // TODO in case of timeouts/missing replies, requests from the map are not removed
+ // consider adding cancel method, that would remove requests from the map and cancel
+ // associated replyCompletableFuture
+
+ return replyCompletableFuture;
+ } catch (VppInvocationException ex) {
+ final CompletableFuture<REPLY> replyCompletableFuture = new CompletableFuture<>();
+ replyCompletableFuture.completeExceptionally(ex);
+ return replyCompletableFuture;
}
}
@SuppressWarnings("unchecked")
public <REQ extends JVppRequest, REPLY extends JVppReply<REQ>, DUMP extends JVppReplyDump<REQ, REPLY>> CompletionStage<DUMP> send(
REQ req, DUMP emptyReplyDump) {
- synchronized(requests) {
- try {
- final CompletableDumpFuture<DUMP> replyCompletableFuture;
- final int contextId = jvpp.send(req);
-
- if(!(req instanceof JVppDump)) {
- throw new IllegalArgumentException("Send without empty reply dump has to be used in case of regular calls");
- }
- replyCompletableFuture = new CompletableDumpFuture<>(contextId, emptyReplyDump);
-
- requests.put(contextId, replyCompletableFuture);
- requests.put(registry.controlPing(jvpp.getClass()), replyCompletableFuture);
-
- // TODO in case of timeouts/missing replies, requests from the map are not removed
- // consider adding cancel method, that would remove requests from the map and cancel
- // associated replyCompletableFuture
-
- return replyCompletableFuture;
- } catch (VppInvocationException ex) {
- final CompletableFuture<DUMP> replyCompletableFuture = new CompletableFuture<>();
- replyCompletableFuture.completeExceptionally(ex);
- return replyCompletableFuture;
- }
- }
+ try {
+ // jvpp.send() and registry.controlPing() can go to waiting state if sending queue is full,
+ // putting it into same synchronization block as used by receiving part (synchronized(requests))
+ // can lead to deadlock between these two sides or at least slowing sending process by slow reader
+ final CompletableDumpFuture<DUMP> replyDumpFuture;
+ final int contextId = jvpp.send(req);
+
+ if(!(req instanceof JVppDump)) {
+ throw new IllegalArgumentException("Send without empty reply dump has to be used in case of regular calls");
+ }
+
+ synchronized(requests) {
+ CompletableFuture<? extends JVppReply<?>> replyFuture = requests.get(contextId);
+ if (replyFuture == null) {
+ // reply not received yet, put new future to map
+ replyDumpFuture = new CompletableDumpFuture<>(contextId, emptyReplyDump);
+ requests.put(contextId, replyDumpFuture);
+ } else {
+ // reply already received, save existing future
+ replyDumpFuture = (CompletableDumpFuture<DUMP>) replyFuture;
+ }
+ }
+
+ final int pingId = registry.controlPing(jvpp.getClass());
+
+ synchronized(requests) {
+ if (requests.remove(pingId) == null) {
+ // reply not received yet, put future into map under pingId
+ requests.put(pingId, replyDumpFuture);
+ } else {
+ // reply already received, complete future
+ // ping reply couldn't complete the future because it is not in map under
+ // ping id
+ replyDumpFuture.complete(replyDumpFuture.getReplyDump());
+ requests.remove(contextId);
+ }
+ }
+
+ // TODO in case of timeouts/missing replies, requests from the map are not removed
+ // consider adding cancel method, that would remove requests from the map and cancel
+ // associated replyCompletableFuture
+
+ return replyDumpFuture;
+ } catch (VppInvocationException ex) {
+ final CompletableFuture<DUMP> replyCompletableFuture = new CompletableFuture<>();
+ replyCompletableFuture.completeExceptionally(ex);
+ return replyCompletableFuture;
+ }
}
public static final class CompletableDumpFuture<T extends JVppReplyDump<?, ?>> extends CompletableFuture<T> {
Code Review / vpp.git / blobdiff