Com: Allow runtime bypass of freeListLib

By environment or iocsh variable.

modules/libcom/src/freeList/freeList.h

@@ -29,6 +29,8 @@
 extern "C" {
 #endif
 
+LIBCOM_API extern int freeListBypass;
+
 LIBCOM_API void epicsStdCall freeListInitPvt(void **ppvt, int size, int malloc);
 LIBCOM_API void * epicsStdCall freeListCalloc(void *pvt);
 LIBCOM_API void * epicsStdCall freeListMalloc(void *pvt);

modules/libcom/src/freeList/freeListLib.c

@@ -26,6 +26,20 @@
 #include "epicsMutex.h"
 #include "freeList.h"
 #include "adjustment.h"
+#include "errlog.h"
+#include "epicsString.h"
+#include "epicsAtomic.h"
+#include "epicsExport.h"
+
+/* Bypass free list and directly call malloc() every time? */
+int freeListBypass
+#ifdef EPICS_FREELIST_DEBUG
+    = 1;
+#else
+    = 2; /* checks environment $EPICS_FREELIST_BYPASS */
+#endif
+
+epicsExportAddress(int, freeListBypass);
 
 typedef struct allocMem {
     struct allocMem     *next;
@@ -44,10 +58,25 @@ LIBCOM_API void epicsStdCall
     freeListInitPvt(void **ppvt,int size,int nmalloc)
 {
     FREELISTPVT *pfl;
+    int bypass = epicsAtomicGetIntT(&freeListBypass);
+
+    if(bypass==2) {
+        const char *str = getenv("EPICS_FREELIST_BYPASS");
+
+        if(str && epicsStrCaseCmp(str, "YES")==0) {
+            bypass = 1;
+        } else if(!str || str[0]=='\0' || epicsStrCaseCmp(str, "NO")==0) {
+            bypass = 0;
+        } else {
+            errlogPrintf(ERL_WARNING " EPICS_FREELIST_BYPASS expected to be YES, NO, or empty.  Not \"%s\"\n", str);
+        }
+        epicsAtomicSetIntT(&freeListBypass, bypass);
+    }
 
     pfl = callocMustSucceed(1,sizeof(FREELISTPVT), "freeListInitPvt");
     pfl->size = adjustToWorstCaseAlignment(size);
-    pfl->nmalloc = nmalloc;
+    if(!bypass)
+        pfl->nmalloc = nmalloc; /* nmalloc==0 to bypass */
     pfl->head = NULL;
     pfl->mallochead = NULL;
     pfl->nBlocksAvailable = 0u;
@@ -60,28 +89,26 @@ LIBCOM_API void epicsStdCall
 LIBCOM_API void * epicsStdCall freeListCalloc(void *pvt)
 {
     FREELISTPVT *pfl = pvt;
-#   ifdef EPICS_FREELIST_DEBUG
-    return callocMustSucceed(1,pfl->size,"freeList Debug Calloc");
-#   else
     void        *ptemp;
 
-    ptemp = freeListMalloc(pvt);
-    if(ptemp) memset((char *)ptemp,0,pfl->size);
+    if(!pfl->nmalloc)
+        ptemp = calloc(1u, pfl->size);
+    else if(!!(ptemp = freeListMalloc(pvt)))
+        memset((char *)ptemp,0,pfl->size);
     return(ptemp);
-#   endif
 }
 
 LIBCOM_API void * epicsStdCall freeListMalloc(void *pvt)
 {
     FREELISTPVT *pfl = pvt;
-#   ifdef EPICS_FREELIST_DEBUG
-    return callocMustSucceed(1,pfl->size,"freeList Debug Malloc");
-#   else
     void        *ptemp;
     void        **ppnext;
     allocMem    *pallocmem;
     int         i;
 
+    if(!pfl->nmalloc)
+        return malloc(pfl->size);
+
     epicsMutexMustLock(pfl->lock);
     ptemp = pfl->head;
     if(ptemp==0) {
@@ -125,18 +152,18 @@ LIBCOM_API void * epicsStdCall freeListMalloc(void *pvt)
     VALGRIND_MEMPOOL_FREE(pfl, ptemp);
     VALGRIND_MEMPOOL_ALLOC(pfl, ptemp, pfl->size);
     return(ptemp);
-#   endif
 }
 
 LIBCOM_API void epicsStdCall freeListFree(void *pvt,void*pmem)
 {
     FREELISTPVT *pfl = pvt;
-#   ifdef EPICS_FREELIST_DEBUG
-    memset ( pmem, 0xdd, pfl->size );
-    free(pmem);
-#   else
     void        **ppnext;
 
+    if(!pfl->nmalloc) {
+        free(pmem);
+        return;
+    }
+
     VALGRIND_MEMPOOL_FREE(pvt, pmem);
     VALGRIND_MEMPOOL_ALLOC(pvt, pmem, sizeof(void*));
 
@@ -146,7 +173,6 @@ LIBCOM_API void epicsStdCall freeListFree(void *pvt,void*pmem)
     pfl->head = pmem;
     pfl->nBlocksAvailable++;
     epicsMutexUnlock(pfl->lock);
-#   endif
 }
 
 LIBCOM_API void epicsStdCall freeListCleanup(void *pvt)

modules/libcom/src/iocsh/libComRegister.c

@@ -25,6 +25,7 @@
 #include "taskwd.h"
 #include "registry.h"
 #include "epicsGeneralTime.h"
+#include "freeList.h"
 #include "libComRegister.h"
 
 /* Register the PWD environment variable when the cd IOC shell function is
@@ -467,7 +468,11 @@ static void installLastResortEventProviderCallFunc(const iocshArgBuf *args)
     installLastResortEventProvider();
 }
 
-static iocshVarDef asCheckClientIPDef[] = { { "asCheckClientIP", iocshArgInt, 0 }, { NULL, iocshArgInt, NULL } };
+static iocshVarDef comDefs[] = {
+    { "asCheckClientIP", iocshArgInt, 0 },
+    { "freeListBypass", iocshArgInt, 0 },
+    { NULL, iocshArgInt, NULL }
+};
 
 void epicsStdCall libComRegister(void)
 {
@@ -504,6 +509,7 @@ void epicsStdCall libComRegister(void)
     iocshRegister(&generalTimeReportFuncDef,generalTimeReportCallFunc);
     iocshRegister(&installLastResortEventProviderFuncDef, installLastResortEventProviderCallFunc);
 
-    asCheckClientIPDef[0].pval = &asCheckClientIP;
-    iocshRegisterVariable(asCheckClientIPDef);
+    comDefs[0].pval = &asCheckClientIP;
+    comDefs[1].pval = &freeListBypass;
+    iocshRegisterVariable(comDefs);
 }