Major cleanup of internal mutex locking. Be more consistant in how we do

things, and avoid potential deadlocks caused when a thread holding a uClibc
internal lock get canceled and terminates without releasing the lock.  This
change also provides a single place, bits/uClibc_mutex.h, for thread libraries
to modify to change all instances of internal locking.

8 files changed, 98 insertions, 73 deletions

diff --git a/libc/stdlib/malloc-standard/calloc.c b/libc/stdlib/malloc-standard/calloc.c
index 99e8884ad..b94fb372b 100644
--- a/libc/stdlib/malloc-standard/calloc.c
+++ b/libc/stdlib/malloc-standard/calloc.c
@@ -36,7 +36,7 @@ void* calloc(size_t n_elements, size_t elem_size)
 	return NULL;
     }
 
-    LOCK;
+    __MALLOC_LOCK;
     mem = malloc(size);
     if (mem != 0) {
 	p = mem2chunk(mem);
@@ -88,7 +88,7 @@ void* calloc(size_t n_elements, size_t elem_size)
 	}
 #endif
     }
-    UNLOCK;
+    __MALLOC_UNLOCK;
     return mem;
 }
 
diff --git a/libc/stdlib/malloc-standard/free.c b/libc/stdlib/malloc-standard/free.c
index e0c6ef061..4d24697be 100644
--- a/libc/stdlib/malloc-standard/free.c
+++ b/libc/stdlib/malloc-standard/free.c
@@ -282,7 +282,7 @@ void free(void* mem)
     if (mem == NULL)
 	return;
 
-    LOCK;
+    __MALLOC_LOCK;
     av = get_malloc_state();
     p = mem2chunk(mem);
     size = chunksize(p);
@@ -406,6 +406,6 @@ void free(void* mem)
 	av->mmapped_mem -= (size + offset);
 	munmap((char*)p - offset, size + offset);
     }
-    UNLOCK;
+    __MALLOC_UNLOCK;
 }
 
diff --git a/libc/stdlib/malloc-standard/mallinfo.c b/libc/stdlib/malloc-standard/mallinfo.c
index 4f274ed32..18331010a 100644
--- a/libc/stdlib/malloc-standard/mallinfo.c
+++ b/libc/stdlib/malloc-standard/mallinfo.c
@@ -32,7 +32,7 @@ struct mallinfo mallinfo(void)
     int nblocks;
     int nfastblocks;
 
-    LOCK;
+    __MALLOC_LOCK;
     av = get_malloc_state();
     /* Ensure initialization */
     if (av->top == 0)  {
@@ -77,7 +77,7 @@ struct mallinfo mallinfo(void)
     mi.fsmblks = fastavail;
     mi.keepcost = chunksize(av->top);
     mi.usmblks = av->max_total_mem;
-    UNLOCK;
+    __MALLOC_UNLOCK;
     return mi;
 }
 libc_hidden_def(mallinfo)
@@ -91,19 +91,36 @@ void malloc_stats(FILE *file)
     }
 
     mi = mallinfo();
-    fprintf(file, "total bytes allocated             = %10u\n", (unsigned int)(mi.arena + mi.hblkhd));
-    fprintf(file, "total bytes in use bytes          = %10u\n", (unsigned int)(mi.uordblks + mi.hblkhd));
-    fprintf(file, "total non-mmapped bytes allocated = %10d\n", mi.arena);
-    fprintf(file, "number of mmapped regions         = %10d\n", mi.hblks);
-    fprintf(file, "total allocated mmap space        = %10d\n", mi.hblkhd);
-    fprintf(file, "total allocated sbrk space        = %10d\n", mi.uordblks);
+    fprintf(file,
+	    "total bytes allocated             = %10u\n"
+	    "total bytes in use bytes          = %10u\n"
+	    "total non-mmapped bytes allocated = %10d\n"
+	    "number of mmapped regions         = %10d\n"
+	    "total allocated mmap space        = %10d\n"
+	    "total allocated sbrk space        = %10d\n"
 #if 0
-    fprintf(file, "number of free chunks             = %10d\n", mi.ordblks);
-    fprintf(file, "number of fastbin blocks          = %10d\n", mi.smblks);
-    fprintf(file, "space in freed fastbin blocks     = %10d\n", mi.fsmblks);
+	    "number of free chunks             = %10d\n"
+	    "number of fastbin blocks          = %10d\n"
+	    "space in freed fastbin blocks     = %10d\n"
 #endif
-    fprintf(file, "maximum total allocated space     = %10d\n", mi.usmblks);
-    fprintf(file, "total free space                  = %10d\n", mi.fordblks);
-    fprintf(file, "memory releasable via malloc_trim = %10d\n", mi.keepcost);
+	    "maximum total allocated space     = %10d\n"
+	    "total free space                  = %10d\n"
+	    "memory releasable via malloc_trim = %10d\n",
+
+	    (unsigned int)(mi.arena + mi.hblkhd),
+	    (unsigned int)(mi.uordblks + mi.hblkhd),
+	    mi.arena,
+	    mi.hblks,
+	    mi.hblkhd,
+	    mi.uordblks,
+#if 0
+	    mi.ordblks,
+	    mi.smblks,
+	    mi.fsmblks,
+#endif
+	    mi.usmblks,
+	    mi.fordblks,
+	    mi.keepcost
+	   );
 }
 
diff --git a/libc/stdlib/malloc-standard/malloc.c b/libc/stdlib/malloc-standard/malloc.c
index 7a87ffd36..8c06fdf1f 100644
--- a/libc/stdlib/malloc-standard/malloc.c
+++ b/libc/stdlib/malloc-standard/malloc.c
@@ -17,9 +17,7 @@
 #include "malloc.h"
 
 
-#ifdef __UCLIBC_HAS_THREADS__
-pthread_mutex_t __malloc_lock = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
-#endif
+__UCLIBC_MUTEX_INIT(__malloc_lock, PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP);
 
 /*
    There is exactly one instance of this struct in this malloc.
@@ -825,12 +823,13 @@ void* malloc(size_t bytes)
     mchunkptr       fwd;              /* misc temp for linking */
     mchunkptr       bck;              /* misc temp for linking */
     void *          sysmem;
+    void *          retval;
 
 #if !defined(__MALLOC_GLIBC_COMPAT__)
     if (!bytes) return NULL;
 #endif
 
-    LOCK;
+    __MALLOC_LOCK;
     av = get_malloc_state();
     /*
        Convert request size to internal form by adding (sizeof(size_t)) bytes
@@ -861,8 +860,8 @@ void* malloc(size_t bytes)
 	if ( (victim = *fb) != 0) {
 	    *fb = victim->fd;
 	    check_remalloced_chunk(victim, nb);
-	    UNLOCK;
-	    return chunk2mem(victim);
+	    retval = chunk2mem(victim);
+	    goto DONE;
 	}
     }
 
@@ -885,8 +884,8 @@ void* malloc(size_t bytes)
 	    bck->fd = bin;
 
 	    check_malloced_chunk(victim, nb);
-	    UNLOCK;
-	    return chunk2mem(victim);
+	    retval = chunk2mem(victim);
+	    goto DONE;
 	}
     }
 
@@ -902,7 +901,7 @@ void* malloc(size_t bytes)
 
     else {
 	idx = __malloc_largebin_index(nb);
-	if (have_fastchunks(av)) 
+	if (have_fastchunks(av))
 	    __malloc_consolidate(av);
     }
 
@@ -942,8 +941,8 @@ void* malloc(size_t bytes)
 	    set_foot(remainder, remainder_size);
 
 	    check_malloced_chunk(victim, nb);
-	    UNLOCK;
-	    return chunk2mem(victim);
+	    retval = chunk2mem(victim);
+	    goto DONE;
 	}
 
 	/* remove from unsorted list */
@@ -955,8 +954,8 @@ void* malloc(size_t bytes)
 	if (size == nb) {
 	    set_inuse_bit_at_offset(victim, size);
 	    check_malloced_chunk(victim, nb);
-	    UNLOCK;
-	    return chunk2mem(victim);
+	    retval = chunk2mem(victim);
+	    goto DONE;
 	}
 
 	/* place chunk in bin */
@@ -1019,8 +1018,8 @@ void* malloc(size_t bytes)
 		if (remainder_size < MINSIZE)  {
 		    set_inuse_bit_at_offset(victim, size);
 		    check_malloced_chunk(victim, nb);
-		    UNLOCK;
-		    return chunk2mem(victim);
+		    retval = chunk2mem(victim);
+		    goto DONE;
 		}
 		/* Split */
 		else {
@@ -1031,8 +1030,8 @@ void* malloc(size_t bytes)
 		    set_head(remainder, remainder_size | PREV_INUSE);
 		    set_foot(remainder, remainder_size);
 		    check_malloced_chunk(victim, nb);
-		    UNLOCK;
-		    return chunk2mem(victim);
+		    retval = chunk2mem(victim);
+		    goto DONE;
 		}
 	    }
 	}
@@ -1100,8 +1099,8 @@ void* malloc(size_t bytes)
 	    if (remainder_size < MINSIZE) {
 		set_inuse_bit_at_offset(victim, size);
 		check_malloced_chunk(victim, nb);
-		UNLOCK;
-		return chunk2mem(victim);
+		retval = chunk2mem(victim);
+		goto DONE;
 	    }
 
 	    /* Split */
@@ -1118,8 +1117,8 @@ void* malloc(size_t bytes)
 		set_head(remainder, remainder_size | PREV_INUSE);
 		set_foot(remainder, remainder_size);
 		check_malloced_chunk(victim, nb);
-		UNLOCK;
-		return chunk2mem(victim);
+		retval = chunk2mem(victim);
+		goto DONE;
 	    }
 	}
     }
@@ -1151,13 +1150,15 @@ use_top:
 	set_head(remainder, remainder_size | PREV_INUSE);
 
 	check_malloced_chunk(victim, nb);
-	UNLOCK;
-	return chunk2mem(victim);
+	retval = chunk2mem(victim);
+	goto DONE;
     }
 
     /* If no space in top, relay to handle system-dependent cases */
     sysmem = __malloc_alloc(nb, av);
-    UNLOCK;
-    return sysmem;
+    retval = sysmem;
+DONE:
+    __MALLOC_UNLOCK;
+    return retval;
 }
 
diff --git a/libc/stdlib/malloc-standard/malloc.h b/libc/stdlib/malloc-standard/malloc.h
index 556aef4d7..389f1f7d4 100644
--- a/libc/stdlib/malloc-standard/malloc.h
+++ b/libc/stdlib/malloc-standard/malloc.h
@@ -22,18 +22,17 @@
 #include <malloc.h>
 #include <stdlib.h>
 #include <sys/mman.h>
+#include <bits/uClibc_mutex.h>
 
 libc_hidden_proto(mmap)
 libc_hidden_proto(sysconf)
 libc_hidden_proto(sbrk)
 libc_hidden_proto(abort)
 
-#ifdef __UCLIBC_HAS_THREADS__
-# include <pthread.h>
-extern pthread_mutex_t __malloc_lock;
-#endif
-#define LOCK	__pthread_mutex_lock(&__malloc_lock)
-#define UNLOCK	__pthread_mutex_unlock(&__malloc_lock)
+
+__UCLIBC_MUTEX_EXTERN(__malloc_lock);
+#define __MALLOC_LOCK		__UCLIBC_MUTEX_LOCK(__malloc_lock)
+#define __MALLOC_UNLOCK		__UCLIBC_MUTEX_UNLOCK(__malloc_lock)
 
 
 
diff --git a/libc/stdlib/malloc-standard/mallopt.c b/libc/stdlib/malloc-standard/mallopt.c
index e28792099..053242dbe 100644
--- a/libc/stdlib/malloc-standard/mallopt.c
+++ b/libc/stdlib/malloc-standard/mallopt.c
@@ -25,7 +25,7 @@ int mallopt(int param_number, int value)
 
     ret = 0;
 
-    LOCK;
+    __MALLOC_LOCK;
     av = get_malloc_state();
     /* Ensure initialization/consolidation */
     __malloc_consolidate(av);
@@ -58,7 +58,7 @@ int mallopt(int param_number, int value)
 	    ret = 1;
 	    break;
     }
-    UNLOCK;
+    __MALLOC_UNLOCK;
     return ret;
 }
 
diff --git a/libc/stdlib/malloc-standard/memalign.c b/libc/stdlib/malloc-standard/memalign.c
index 27502893d..7e0674be5 100644
--- a/libc/stdlib/malloc-standard/memalign.c
+++ b/libc/stdlib/malloc-standard/memalign.c
@@ -35,6 +35,7 @@ void* memalign(size_t alignment, size_t bytes)
     mchunkptr       remainder;      /* spare room at end to split off */
     unsigned long    remainder_size; /* its size */
     size_t size;
+    void *retval;
 
     /* If need less alignment than we give anyway, just relay to malloc */
 
@@ -51,7 +52,7 @@ void* memalign(size_t alignment, size_t bytes)
 	alignment = a;
     }
 
-    LOCK;
+    __MALLOC_LOCK;
     checked_request2size(bytes, nb);
 
     /* Strategy: find a spot within that chunk that meets the alignment
@@ -63,8 +64,8 @@ void* memalign(size_t alignment, size_t bytes)
     m  = (char*)(malloc(nb + alignment + MINSIZE));
 
     if (m == 0) {
-	UNLOCK;
-	return 0; /* propagate failure */
+	retval = 0; /* propagate failure */
+	goto DONE;
     }
 
     p = mem2chunk(m);
@@ -92,8 +93,8 @@ void* memalign(size_t alignment, size_t bytes)
 	if (chunk_is_mmapped(p)) {
 	    newp->prev_size = p->prev_size + leadsize;
 	    set_head(newp, newsize|IS_MMAPPED);
-	    UNLOCK;
-	    return chunk2mem(newp);
+	    retval = chunk2mem(newp);
+	    goto DONE;
 	}
 
 	/* Otherwise, give back leader, use the rest */
@@ -120,7 +121,10 @@ void* memalign(size_t alignment, size_t bytes)
     }
 
     check_inuse_chunk(p);
-    UNLOCK;
-    return chunk2mem(p);
+    retval = chunk2mem(p);
+
+ DONE:
+    __MALLOC_UNLOCK;
+	return retval;
 }
 
diff --git a/libc/stdlib/malloc-standard/realloc.c b/libc/stdlib/malloc-standard/realloc.c
index f25d6d989..ef436da0d 100644
--- a/libc/stdlib/malloc-standard/realloc.c
+++ b/libc/stdlib/malloc-standard/realloc.c
@@ -46,6 +46,7 @@ void* realloc(void* oldmem, size_t bytes)
     size_t* s;               /* copy source */
     size_t* d;               /* copy destination */
 
+    void *retval;
 
     /* Check for special cases.  */
     if (! oldmem)
@@ -55,7 +56,7 @@ void* realloc(void* oldmem, size_t bytes)
 	return NULL;
     }
 
-    LOCK;
+    __MALLOC_LOCK;
     av = get_malloc_state();
     checked_request2size(bytes, nb);
 
@@ -82,8 +83,8 @@ void* realloc(void* oldmem, size_t bytes)
 		set_head_size(oldp, nb);
 		av->top = chunk_at_offset(oldp, nb);
 		set_head(av->top, (newsize - nb) | PREV_INUSE);
-		UNLOCK;
-		return chunk2mem(oldp);
+		retval = chunk2mem(oldp);
+		goto DONE;
 	    }
 
 	    /* Try to expand forward into next chunk;  split off remainder below */
@@ -99,8 +100,8 @@ void* realloc(void* oldmem, size_t bytes)
 	    else {
 		newmem = malloc(nb - MALLOC_ALIGN_MASK);
 		if (newmem == 0) {
-		    UNLOCK;
-		    return 0; /* propagate failure */
+		    retval = 0; /* propagate failure */
+		    goto DONE;
 		}
 
 		newp = mem2chunk(newmem);
@@ -149,8 +150,8 @@ void* realloc(void* oldmem, size_t bytes)
 
 		    free(oldmem);
 		    check_inuse_chunk(newp);
-		    UNLOCK;
-		    return chunk2mem(newp);
+		    retval = chunk2mem(newp);
+		    goto DONE;
 		}
 	    }
 	}
@@ -175,8 +176,8 @@ void* realloc(void* oldmem, size_t bytes)
 	}
 
 	check_inuse_chunk(newp);
-	UNLOCK;
-	return chunk2mem(newp);
+	retval = chunk2mem(newp);
+	goto DONE;
     }
 
     /*
@@ -194,8 +195,8 @@ void* realloc(void* oldmem, size_t bytes)
 
 	/* don't need to remap if still within same page */
 	if (oldsize == newsize - offset) {
-	    UNLOCK;
-	    return oldmem;
+	    retval = oldmem;
+	    goto DONE;
 	}
 
 	cp = (char*)mremap((char*)oldp - offset, oldsize + offset, newsize, 1);
@@ -216,8 +217,8 @@ void* realloc(void* oldmem, size_t bytes)
 	    if (sum > (unsigned long)(av->max_total_mem))
 		av->max_total_mem = sum;
 
-	    UNLOCK;
-	    return chunk2mem(newp);
+	    retval = chunk2mem(newp);
+	    goto DONE;
 	}
 
 	/* Note the extra (sizeof(size_t)) overhead. */
@@ -231,8 +232,11 @@ void* realloc(void* oldmem, size_t bytes)
 		free(oldmem);
 	    }
 	}
-	UNLOCK;
-	return newmem;
+	retval = newmem;
     }
+
+ DONE:
+    __MALLOC_UNLOCK;
+    return retval;
 }