improved imudp real-time scheduling support & bugfix

The original code had quite some issues, which are fixed by this
commit. Also we do more error checking now.

Signed-off-by: Rainer Gerhards <rgerhards@adiscon.com>

4 files changed, 38 insertions, 1 deletions

diff --git a/runtime/rsyslog.c b/runtime/rsyslog.c
index a9794840..2722fd6c 100644
--- a/runtime/rsyslog.c
+++ b/runtime/rsyslog.c
@@ -84,6 +84,12 @@
 #include "strgen.h"
 #include "atomic.h"
 
+#ifdef HAVE_PTHREAD_SETSCHEDPARAM
+struct sched_param default_sched_param;
+pthread_attr_t default_thread_attr;
+int default_thr_sched_policy;
+#endif
+
 /* forward definitions */
 static rsRetVal dfltErrLogger(int, uchar *errMsg);
 
@@ -138,6 +144,18 @@ rsrtInit(char **ppErrObj, obj_if_t *pObjIF)
 
 	if(iRefCount == 0) {
 		/* init runtime only if not yet done */
+#ifdef HAVE_PTHREAD_SETSCHEDPARAM
+	    	CHKiRet(pthread_getschedparam(pthread_self(),
+			    		      &default_thr_sched_policy,
+					      &default_sched_param));
+		CHKiRet(pthread_attr_init(&default_thread_attr));
+		CHKiRet(pthread_attr_setschedpolicy(&default_thread_attr,
+			    			    default_thr_sched_policy));
+		CHKiRet(pthread_attr_setschedparam(&default_thread_attr,
+			    			   &default_sched_param));
+		CHKiRet(pthread_attr_setinheritsched(&default_thread_attr,
+			    			     PTHREAD_EXPLICIT_SCHED));
+#endif
 		if(ppErrObj != NULL) *ppErrObj = "obj";
 		CHKiRet(objClassInit(NULL)); /* *THIS* *MUST* always be the first class initilizer being called! */
 		CHKiRet(objGetObjInterface(pObjIF)); /* this provides the root pointer for all other queries */
diff --git a/runtime/rsyslog.h b/runtime/rsyslog.h
index 3e6ac4af..0742a2ed 100644
--- a/runtime/rsyslog.h
+++ b/runtime/rsyslog.h
@@ -25,6 +25,7 @@
  */
 #ifndef INCLUDED_RSYSLOG_H
 #define INCLUDED_RSYSLOG_H
+#include <pthread.h>
 #include "typedefs.h"
 
 /* ############################################################# *
@@ -411,6 +412,12 @@ typedef enum rsObjectID rsObjID;
 #define RSFREEOBJ(x) {(x)->OID = OIDrsFreed; free(x);}
 #endif
 
+#ifdef HAVE_PTHREAD_SETSCHEDPARAM
+extern struct sched_param default_sched_param;
+extern pthread_attr_t default_thread_attr;
+extern int default_thr_sched_policy;
+#endif
+
 
 /* for the time being, we do our own portability handling here. It
  * looks like autotools either does not yet support checks for it, or
diff --git a/runtime/stream.c b/runtime/stream.c
index 260b59ef..658aba11 100644
--- a/runtime/stream.c
+++ b/runtime/stream.c
@@ -669,7 +669,13 @@ static rsRetVal strmConstructFinalize(strm_t *pThis)
 		}
 		pThis->pIOBuf = pThis->asyncBuf[0].pBuf;
 		pThis->bStopWriter = 0;
-		if(pthread_create(&pThis->writerThreadID, NULL, asyncWriterThread, pThis) != 0)
+		if(pthread_create(&pThis->writerThreadID,
+#ifdef HAVE_PTHREAD_SETSCHEDPARAM
+			    	  &default_thread_attr,
+#else
+				  NULL,
+#endif
+				  asyncWriterThread, pThis) != 0)
 			DBGPRINTF("ERROR: stream %p cold not create writer thread\n", pThis);
 	} else {
 		/* we work synchronously, so we need to alloc a fixed pIOBuf */
diff --git a/runtime/wtp.c b/runtime/wtp.c
index ece80911..e615fb19 100644
--- a/runtime/wtp.c
+++ b/runtime/wtp.c
@@ -90,6 +90,12 @@ BEGINobjConstruct(wtp) /* be sure to specify the object type also in END macro!
 	pthread_mutex_init(&pThis->mutWtp, NULL);
 	pthread_cond_init(&pThis->condThrdTrm, NULL);
 	pthread_attr_init(&pThis->attrThrd);
+	/* Set thread scheduling policy to default */
+#ifdef HAVE_PTHREAD_SETSCHEDPARAM
+	pthread_attr_setschedpolicy(&pThis->attrThrd, default_thr_sched_policy);
+	pthread_attr_setschedparam(&pThis->attrThrd, &default_sched_param);
+	pthread_attr_setinheritsched(&pThis->attrThrd, PTHREAD_EXPLICIT_SCHED);
+#endif
 	pthread_attr_setdetachstate(&pThis->attrThrd, PTHREAD_CREATE_DETACHED);
 	/* set all function pointers to "not implemented" dummy so that we can safely call them */
 	pThis->pfChkStopWrkr = NotImplementedDummy;