PR10524: reduce massive-uprobe script modules' .data consumption

The general approach is to rip out task_finder_tgt's from all over the
place (including the unwindsym vmcbs, and the stap_uprobe_specs), and
instead have a small handful of them: one for all unwindsyms, and one
per abstract probed process (PID or NAME).  These are in turn shared
by all new stap_unwind_specs by index.

Before:  probe process("./stap").function("*")

-rw-r--r--. 1 fche users 11775283 2009-09-08 20:26 /var/tmp/fche/systemtap/cache/96/stap_96c0479d674db55ec98d8a8750a790e7_7989596.ko
   text    data     bss     dec     hex filename
 445158 8351944 4306472 13103574 c7f1d6 /var/tmp/fche/systemtap/cache/96/stap_96c0479d674db55ec98d8a8750a790e7_7989596.ko

After: (Note how data shrank, though text gained a bit in const-init-data.)

-rw-r--r--. 1 fche users  4021569 2009-09-08 20:27 /var/tmp/fche/systemtap/cache/e4/stap_e46e88634efd850b1586e81c231c239a_8058419.ko
   text    data     bss     dec     hex filename
1896511    2192 4324808 6223511  5ef697 /var/tmp/fche/systemtap/cache/e4/stap_e46e88634efd850b1586e81c231c239a_8058419.ko

* tapsets.cxx (uprobe_derived_probe_group): Rewrite emit_module_decls,
  and adjust emit_module_init.
* runtime/sym.c (_stp_sym_init): Initialize unwindsyms-shared vmcb.
* runtime/sym.h (_stp_module): Remove *vmcb field.
* translate.cxx (emit_module_init, dump_unwindsyms): Adapt.
* translate.h (assert_0_indent): Flush output before possibly assert-failing.

1 files changed, 0 insertions, 2 deletions

diff --git a/runtime/sym.h b/runtime/sym.h
index 262b1776..ca69345f 100644
--- a/runtime/sym.h
+++ b/runtime/sym.h
@@ -30,8 +30,6 @@ struct _stp_module {
 	struct _stp_section *sections;
   	unsigned num_sections;
 
-        struct stap_task_finder_target *vmcb; /* PR10228 */
-
 	/* A pointer to the struct module. Note that we cannot */
 	/* trust this because as of 2.6.19, there are not yet */
 	/* any notifier hooks that will tell us when a module */