talloc: use a struct for pool headers.

This neatens the code a bit (we should do a similar thing for all the
TALLOC_CHUNK macros).

Two subtler changes:
(1) As a result of the struct, we actually pack object_count into the 
    talloc header on 32-bit platforms (since the header is 40 bytes, but
    needs to be 16-byte aligned).
(2) I avoid VALGRIND_MAKE_MEM_UNDEFINED on memmove when we resize the
    only entry in a pool; that's done later anyway.

With -O2 on my 11.04 Ubuntu 32-bit x86 laptop, the talloc_pool speed as
measured by testsuite.c actually increases 10%.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/talloc/testsuite.c b/lib/talloc/testsuite.c
index 71917038be..eaab9d7cf0 100644
--- a/lib/talloc/testsuite.c
+++ b/lib/talloc/testsuite.c
@@ -848,7 +848,7 @@ static bool test_speed(void)
 			p1 = talloc_size(ctx, loop % 100);
 			p2 = talloc_strdup(p1, "foo bar");
 			p3 = talloc_size(p1, 300);
-			talloc_free_children(ctx);
+			talloc_free(p1);
 		}
 		count += 3 * loop;
 	} while (timeval_elapsed(&tv) < 5.0);