WL#3064 - waiting threads - wait-for graph and deadlock detection

client/mysqltest.c:
  compiler warnings
configure.in:
  remove old tests for unused programs
  disable the use of gcc built-ins if smp assembler atomics were selected explictily.
  add waiting_threads.o to THREAD_LOBJECTS
include/lf.h:
  replace the end-of-stack pointer with the pointer to the end-of-stack pointer.
  the latter could be stored in THD (mysys_vars) and updated in pool-of-threads
  scheduler.
  constructor/destructor in lf-alloc
include/my_pthread.h:
  shuffle set_timespec/set_timespec_nsec macros a bit to be able to fill
  several timeout structures with only one my_getsystime() call
include/waiting_threads.h:
  waiting threads - wait-for graph and deadlock detection
mysys/Makefile.am:
  add waiting_threads.c
mysys/lf_alloc-pin.c:
  replace the end-of-stack pointer with the pointer to the end-of-stack pointer.
  the latter could be stored in THD (mysys_vars) and updated in pool-of-threads
  scheduler.
  constructor/destructor in lf-alloc
mysys/lf_hash.c:
  constructor/destructor in lf-alloc
mysys/my_thr_init.c:
  remember end-of-stack pointer in the mysys_var
mysys/waiting_threads.c:
  waiting threads - wait-for graph and deadlock detection
storage/maria/ha_maria.cc:
  replace the end-of-stack pointer with the pointer to the end-of-stack pointer.
  the latter could be stored in THD (mysys_vars) and updated in pool-of-threads
  scheduler.
storage/maria/ma_commit.c:
  replace the end-of-stack pointer with the pointer to the end-of-stack pointer.
  the latter could be stored in THD (mysys_vars) and updated in pool-of-threads
  scheduler.
storage/maria/trnman.c:
  replace the end-of-stack pointer with the pointer to the end-of-stack pointer.
  the latter could be stored in THD (mysys_vars) and updated in pool-of-threads
  scheduler.
storage/maria/trnman_public.h:
  replace the end-of-stack pointer with the pointer to the end-of-stack pointer.
  the latter could be stored in THD (mysys_vars) and updated in pool-of-threads
  scheduler.
storage/maria/unittest/trnman-t.c:
  replace the end-of-stack pointer with the pointer to the end-of-stack pointer.
  the latter could be stored in THD (mysys_vars) and updated in pool-of-threads
  scheduler.
unittest/mysys/Makefile.am:
  add waiting_threads-t
unittest/mysys/lf-t.c:
  factor out the common code for multi-threaded stress unit tests
  move lf tests to a separate file
unittest/mysys/my_atomic-t.c:
  factor out the common code for multi-threaded stress unit tests
  move lf tests to a separate file
unittest/mysys/thr_template.c:
  factor out the common code for multi-threaded stress unit tests
unittest/mysys/waiting_threads-t.c:
  wt tests

1 files changed, 13 insertions, 2 deletions

diff --git a/mysys/lf_hash.c b/mysys/lf_hash.c
index c197cc99711..008abef0c8b 100644
--- a/mysys/lf_hash.c
+++ b/mysys/lf_hash.c
@@ -299,11 +299,22 @@ static int initialize_bucket(LF_HASH *, LF_SLIST * volatile*, uint, LF_PINS *);
 
 /*
   Initializes lf_hash, the arguments are compatible with hash_init
+
+  @@note element_size sets both the size of allocated memory block for
+  lf_alloc and a size of memcpy'ed block size in lf_hash_insert. Typically
+  they are the same, indeed. But LF_HASH::element_size can be decreased
+  after lf_hash_init, and then lf_alloc will allocate larger block that
+  lf_hash_insert will copy over. It is desireable if part of the element
+  is expensive to initialize - for example if there is a mutex or
+  DYNAMIC_ARRAY. In this case they should be initialize in the
+  LF_ALLOCATOR::constructor, and lf_hash_insert should not overwrite them.
+  See wt_init() for example.
 */
 void lf_hash_init(LF_HASH *hash, uint element_size, uint flags,
                   uint key_offset, uint key_length, hash_get_key get_key,
                   CHARSET_INFO *charset)
 {
+  compile_time_assert(sizeof(LF_SLIST) == LF_HASH_OVERHEAD);
   lf_alloc_init(&hash->alloc, sizeof(LF_SLIST)+element_size,
                 offsetof(LF_SLIST, key));
   lf_dynarray_init(&hash->array, sizeof(LF_SLIST *));
@@ -453,7 +464,7 @@ void *lf_hash_search(LF_HASH *hash, LF_PINS *pins, const void *key, uint keylen)
   return found ? found+1 : 0;
 }
 
-static const uchar *dummy_key= "";
+static const uchar *dummy_key= (uchar*)"";
 
 /*
   RETURN
@@ -473,7 +484,7 @@ static int initialize_bucket(LF_HASH *hash, LF_SLIST * volatile *node,
       unlikely(initialize_bucket(hash, el, parent, pins)))
     return -1;
   dummy->hashnr= my_reverse_bits(bucket) | 0; /* dummy node */
-  dummy->key= (char*) dummy_key;
+  dummy->key= dummy_key;
   dummy->keylen= 0;
   if ((cur= linsert(el, hash->charset, dummy, pins, LF_HASH_UNIQUE)))
   {