core: mem - join free packets option can be set from config

- better control over existing code for joining free memory fragments
- existing QM_JOIN_FREE renamed to MEM_JOIN_FREE - to be used in other
  memory managers than q_malloc
- new cfg parameter mem_join - if set to 1, q_malloc does join of free
  memory fragments. default is 0. in use if MEM_JOIN_FREE is defined

Makefile.defs

@@ -560,6 +560,8 @@ data_target = $(prefix)/$(data_dir)
 #		now.
 # -DDBG_MALLOC
 #		issues additional debugging information if lock/unlock is called
+# -DMEM_JOIN_FREE
+#		enable the join of free memory chunks (see also mem_join cfg param)
 # -DFAST_LOCK
 #		uses fast arhitecture specific locking (see the arh. specific section)
 # -DUSE_SYSV_SEM
@@ -704,6 +706,7 @@ C_DEFS= $(extra_defs) \
 
 ifeq ($(MEMDBG), 1)
 	C_DEFS+= -DDBG_QM_MALLOC
+	C_DEFS+= -DMEM_JOIN_FREE
 else
 	C_DEFS+= -DF_MALLOC
 endif

cfg.lex

@@ -398,7 +398,8 @@ SYN_BRANCH syn_branch
 MEMLOG		"memlog"|"mem_log"
 MEMDBG		"memdbg"|"mem_dbg"
 MEMSUM		"mem_summary"
-MEMSAFETY		"mem_safety"
+MEMSAFETY	"mem_safety"
+MEMJOIN		"mem_join"
 CORELOG		"corelog"|"core_log"
 SIP_WARNING sip_warning
 SERVER_SIGNATURE server_signature
@@ -799,6 +800,7 @@ IMPORTFILE      "import_file"
 <INITIAL>{MEMDBG}	{ count(); yylval.strval=yytext; return MEMDBG; }
 <INITIAL>{MEMSUM}	{ count(); yylval.strval=yytext; return MEMSUM; }
 <INITIAL>{MEMSAFETY}	{ count(); yylval.strval=yytext; return MEMSAFETY; }
+<INITIAL>{MEMJOIN}	{ count(); yylval.strval=yytext; return MEMJOIN; }
 <INITIAL>{CORELOG}	{ count(); yylval.strval=yytext; return CORELOG; }
 <INITIAL>{SIP_WARNING}	{ count(); yylval.strval=yytext; return SIP_WARNING; }
 <INITIAL>{USER}		{ count(); yylval.strval=yytext; return USER; }

cfg.y

@@ -453,6 +453,7 @@ extern char *finame;
 %token MEMDBG
 %token MEMSUM
 %token MEMSAFETY
+%token MEMJOIN
 %token CORELOG
 %token SIP_WARNING
 %token SERVER_SIGNATURE
@@ -962,6 +963,8 @@ assign_stm:
 	| MEMSUM EQUAL error { yyerror("int value expected"); }
 	| MEMSAFETY EQUAL intno { default_core_cfg.mem_safety=$3; }
 	| MEMSAFETY EQUAL error { yyerror("int value expected"); }
+	| MEMJOIN EQUAL intno { default_core_cfg.mem_join=$3; }
+	| MEMJOIN EQUAL error { yyerror("int value expected"); }
 	| CORELOG EQUAL intno { default_core_cfg.corelog=$3; }
 	| CORELOG EQUAL error { yyerror("int value expected"); }
 	| SIP_WARNING EQUAL NUMBER { sip_warning=$3; }

cfg_core.c

@@ -122,6 +122,7 @@ struct cfg_group_core default_core_cfg = {
 	3, /*!< mem_summary -flags: 0 off, 1 pkg_status, 2 shm_status,
 		4 pkg_sums, 8 shm_sums, 16 short_status */
 	0, /*!< mem_safety - 0 disabled */
+	0, /*!< mem_join - 0 disabled */
 	L_ERR, /*!< corelog */
 	L_ERR, /*!< latency log */
 	0, /*!< latency limit db */
@@ -315,6 +316,8 @@ cfg_def_t core_cfg_def[] = {
 		" 16 - short status instead of dump" },
 	{"mem_safety",		CFG_VAR_INT|CFG_ATOMIC,	0, 0, 0, 0,
 		"safety level for memory operations"},
+	{"mem_join",		CFG_VAR_INT|CFG_ATOMIC,	0, 0, 0, 0,
+		"join free memory fragments"},
 	{"corelog",		CFG_VAR_INT|CFG_ATOMIC,	0, 0, 0, 0,
 		"log level for non-critical core error messages"},
 	{"latency_log",		CFG_VAR_INT|CFG_ATOMIC,	0, 0, 0, 0,

cfg_core.h

@@ -109,6 +109,7 @@ struct cfg_group_core {
 	int memlog; /*!< log level for memory status/summary info */
 	int mem_summary; /*!< display memory status/summary info on exit */
 	int mem_safety; /*!< memory safety control option */
+	int mem_join; /*!< memory free fragments join option */
 	int corelog; /*!< log level for non-critcal core error messages */
 	int latency_log; /*!< log level for latency limits messages */
 	int latency_limit_db; /*!< alert limit of running db commands */

mem/q_malloc.c

@@ -428,10 +428,10 @@ void qm_free(struct qm_block* qm, void* p)
 {
 	struct qm_frag* f;
 	unsigned long size;
-#ifdef QM_JOIN_FREE
+#ifdef MEM_JOIN_FREE
 	struct qm_frag* next;
 	struct qm_frag* prev;
-#endif /* QM_JOIN_FREE*/
+#endif /* MEM_JOIN_FREE*/
 
 #ifdef DBG_QM_MALLOC
 	MDBG("qm_free(%p, %p), called from %s: %s(%d)\n", qm, p, file, func, line);
@@ -446,9 +446,6 @@ void qm_free(struct qm_block* qm, void* p)
 		LOG(L_WARN, "WARNING:qm_free: free(0) called\n");
 		return;
 	}
-#ifdef QM_JOIN_FREE
-	next=prev=0;
-#endif /* QM_JOIN_FREE*/
 	f=(struct qm_frag*) ((char*)p-sizeof(struct qm_frag));
 #ifdef DBG_QM_MALLOC
 	qm_debug_frag(qm, f);
@@ -470,43 +467,46 @@ void qm_free(struct qm_block* qm, void* p)
 	sr_event_exec(SREV_PKG_SET_REAL_USED, (void*)qm->real_used);
 #endif
 
-#ifdef QM_JOIN_FREE
-	/* mark this fragment as used (might fall into the middle of joined frags)
-	  to give us an extra chance of detecting a double free call (if the joined
-	  fragment has not yet been reused) */
-	f->u.nxt_free=(void*)0x1L; /* bogus value, just to mark it as free */
-	/* join packets if possible*/
-	next=FRAG_NEXT(f);
-	if (((char*)next < (char*)qm->last_frag_end) &&( next->u.is_free)){
+#ifdef MEM_JOIN_FREE
+	if(unlikely(cfg_get(core, core_cfg, mem_join)!=0)) {
+		next=prev=0;
+		/* mark this fragment as used (might fall into the middle of joined frags)
+		  to give us an extra chance of detecting a double free call (if the joined
+		  fragment has not yet been reused) */
+		f->u.nxt_free=(void*)0x1L; /* bogus value, just to mark it as free */
+		/* join packets if possible*/
+		next=FRAG_NEXT(f);
+		if (((char*)next < (char*)qm->last_frag_end) &&( next->u.is_free)){
 		/* join */
 #ifdef DBG_QM_MALLOC
-		qm_debug_frag(qm, next);
+			qm_debug_frag(qm, next);
 #endif
-		qm_detach_free(qm, next);
-		size+=next->size+FRAG_OVERHEAD;
-		qm->real_used-=FRAG_OVERHEAD;
-		qm->free_hash[GET_HASH(next->size)].no--; /* FIXME slow */
-	}
+			qm_detach_free(qm, next);
+			size+=next->size+FRAG_OVERHEAD;
+			qm->real_used-=FRAG_OVERHEAD;
+			qm->free_hash[GET_HASH(next->size)].no--; /* FIXME slow */
+		}
 	
-	if (f > qm->first_frag){
-		prev=FRAG_PREV(f);
-		/*	(struct qm_frag*)((char*)f - (struct qm_frag_end*)((char*)f-
+		if (f > qm->first_frag){
+			prev=FRAG_PREV(f);
+			/*	(struct qm_frag*)((char*)f - (struct qm_frag_end*)((char*)f-
 								sizeof(struct qm_frag_end))->size);*/
 #ifdef DBG_QM_MALLOC
-		qm_debug_frag(qm, prev);
+			qm_debug_frag(qm, prev);
 #endif
-		if (prev->u.is_free){
-			/*join*/
-			qm_detach_free(qm, prev);
-			size+=prev->size+FRAG_OVERHEAD;
-			qm->real_used-=FRAG_OVERHEAD;
-			qm->free_hash[GET_HASH(prev->size)].no--; /* FIXME slow */
-			f=prev;
+			if (prev->u.is_free){
+				/*join*/
+				qm_detach_free(qm, prev);
+				size+=prev->size+FRAG_OVERHEAD;
+				qm->real_used-=FRAG_OVERHEAD;
+					qm->free_hash[GET_HASH(prev->size)].no--; /* FIXME slow */
+				f=prev;
+			}
 		}
-	}
-	f->size=size;
-	FRAG_END(f)->size=f->size;
-#endif /* QM_JOIN_FREE*/
+		f->size=size;
+		FRAG_END(f)->size=f->size;
+	} /* if cfg_core->mem_join */
+#endif /* MEM_JOIN_FREE*/
 #ifdef DBG_QM_MALLOC
 	f->file=file;
 	f->func=func;

ver_defs.h

@@ -303,10 +303,10 @@
 #define HAVE_RESOLV_RES_STR ""
 #endif
 
-#ifdef QM_JOIN_FREE 
-#define QM_JOIN_FREE_STR ", QM_JOIN_FREE"
+#ifdef MEM_JOIN_FREE
+#define MEM_JOIN_FREE_STR ", MEM_JOIN_FREE"
 #else
-#define QM_JOIN_FREE_STR ""
+#define MEM_JOIN_FREE_STR ""
 #endif
 
 #ifdef SYSLOG_CALLBACK_SUPPORT