[patch v6 09/12] gdbserver, linux, btrace: add btrace support for linux-low

[markus dot t dot metzger at intel dot com]

From: Markus Metzger <markus.t.metzger@intel.com>

Implement btrace target ops in target linux-low using the common linux-btrace
functions.

2012-12-17 Markus Metzger <markus.t.metzger@intel.com>

gdbserver/
	* linux-low: Include linux-btrace.h.
	(linux_low_enable_btrace): New function.
	(linux_low_read_btrace): New function.
	(linux_target_ops): Add btrace ops.
	* configure.srv (i[34567]86-*-linux*): Add linux-btrace.o.
	Add srv_linux_btrace=yes.
	(x86_64-*-linux*): Add linux-btrace.o.
	Add srv_linux_btrace=yes.
	* configure.ac: Define HAVE_LINUX_BTRACE.
	* config.in: Regenerated.
	* configure: Regenerated.


---
 gdb/gdbserver/config.in     |    3 ++
 gdb/gdbserver/configure     |    6 ++++
 gdb/gdbserver/configure.ac  |    5 ++++
 gdb/gdbserver/configure.srv |    6 +++-
 gdb/gdbserver/linux-low.c   |   57 +++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 75 insertions(+), 2 deletions(-)

diff --git a/gdb/gdbserver/config.in b/gdb/gdbserver/config.in
index b791b89..76fa209 100644
--- a/gdb/gdbserver/config.in
+++ b/gdb/gdbserver/config.in
@@ -73,6 +73,9 @@
 /* Define to 1 if you have the `dl' library (-ldl). */
 #undef HAVE_LIBDL
 
+/* Define if the target supports branch tracing. */
+#undef HAVE_LINUX_BTRACE
+
 /* Define to 1 if you have the <linux/elf.h> header file. */
 #undef HAVE_LINUX_ELF_H
 
diff --git a/gdb/gdbserver/configure b/gdb/gdbserver/configure
index 9ec9340..e2403a3 100755
--- a/gdb/gdbserver/configure
+++ b/gdb/gdbserver/configure
@@ -5144,6 +5144,12 @@ $as_echo "#define HAVE_PTRACE_GETFPXREGS 1" >>confdefs.h
   fi
 fi
 
+if test "${srv_linux_btrace}" = "yes"; then
+
+$as_echo "#define HAVE_LINUX_BTRACE 1" >>confdefs.h
+
+fi
+
 if test "$ac_cv_header_sys_procfs_h" = yes; then
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking for lwpid_t in sys/procfs.h" >&5
 $as_echo_n "checking for lwpid_t in sys/procfs.h... " >&6; }
diff --git a/gdb/gdbserver/configure.ac b/gdb/gdbserver/configure.ac
index 6493c0f..66b9c73 100644
--- a/gdb/gdbserver/configure.ac
+++ b/gdb/gdbserver/configure.ac
@@ -291,6 +291,11 @@ if test "${srv_linux_regsets}" = "yes"; then
   fi
 fi
 
+if test "${srv_linux_btrace}" = "yes"; then
+  AC_DEFINE(HAVE_LINUX_BTRACE, 1,
+	    [Define if the target supports branch tracing.])
+fi
+
 if test "$ac_cv_header_sys_procfs_h" = yes; then
   BFD_HAVE_SYS_PROCFS_TYPE(lwpid_t)
   BFD_HAVE_SYS_PROCFS_TYPE(psaddr_t)
diff --git a/gdb/gdbserver/configure.srv b/gdb/gdbserver/configure.srv
index d1e04a9..3492c16 100644
--- a/gdb/gdbserver/configure.srv
+++ b/gdb/gdbserver/configure.srv
@@ -97,10 +97,11 @@ case "${target}" in
 			    srv_xmlfiles="${srv_xmlfiles} $srv_amd64_linux_xmlfiles"
 			fi
 			srv_tgtobj="linux-low.o linux-osdata.o linux-x86-low.o i386-low.o i387-fp.o linux-procfs.o"
-			srv_tgtobj="${srv_tgtobj} linux-ptrace.o"
+			srv_tgtobj="${srv_tgtobj} linux-ptrace.o linux-btrace.o"
 			srv_linux_usrregs=yes
 			srv_linux_regsets=yes
 			srv_linux_thread_db=yes
+			srv_linux_btrace=yes
 			ipa_obj="${ipa_i386_linux_regobj} linux-i386-ipa.o"
 			;;
   i[34567]86-*-lynxos*)	srv_regobj="i386.o"
@@ -293,11 +294,12 @@ case "${target}" in
 			;;
   x86_64-*-linux*)	srv_regobj="$srv_amd64_linux_regobj $srv_i386_linux_regobj"
 			srv_tgtobj="linux-low.o linux-osdata.o linux-x86-low.o i386-low.o i387-fp.o linux-procfs.o"
-			srv_tgtobj="${srv_tgtobj} linux-ptrace.o"
+			srv_tgtobj="${srv_tgtobj} linux-ptrace.o linux-btrace.o"
 			srv_xmlfiles="$srv_i386_linux_xmlfiles $srv_amd64_linux_xmlfiles"
 			srv_linux_usrregs=yes # This is for i386 progs.
 			srv_linux_regsets=yes
 			srv_linux_thread_db=yes
+			srv_linux_btrace=yes
 			ipa_obj="${ipa_amd64_linux_regobj} linux-amd64-ipa.o"
 			;;
   x86_64-*-mingw*)	srv_regobj="$srv_amd64_regobj"
diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c
index c697f6b..d1a01f1 100644
--- a/gdb/gdbserver/linux-low.c
+++ b/gdb/gdbserver/linux-low.c
@@ -84,6 +84,10 @@
 #endif
 #endif
 
+#ifdef HAVE_LINUX_BTRACE
+#include "linux-btrace.h"
+#endif
+
 #ifndef HAVE_ELF32_AUXV_T
 /* Copied from glibc's elf.h.  */
 typedef struct
@@ -5794,6 +5798,46 @@ linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
   return len;
 }
 
+#ifdef HAVE_LINUX_BTRACE
+
+/* Enable branch tracing.  */
+
+static struct btrace_target_info *
+linux_low_enable_btrace (ptid_t ptid)
+{
+  struct btrace_target_info *tinfo;
+
+  tinfo = linux_enable_btrace (ptid);
+  if (tinfo != NULL)
+    tinfo->ptr_bits = register_size (0) * 8;
+
+  return tinfo;
+}
+
+/* Read branch trace data as btrace xml document.  */
+
+static void
+linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer)
+{
+  VEC (btrace_block_s) *btrace;
+  struct btrace_block *block;
+  int i;
+
+  btrace = linux_read_btrace (tinfo);
+
+  buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
+  buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
+
+  for (i = 0; VEC_iterate (btrace_block_s, btrace, i, block); i++)
+    buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
+		       paddress (block->begin), paddress (block->end));
+
+  buffer_grow_str (buffer, "</btrace>\n");
+
+  VEC_free (btrace_block_s, btrace);
+}
+#endif /* HAVE_LINUX_BTRACE */
+
 static struct target_ops linux_target_ops = {
   linux_create_inferior,
   linux_attach,
@@ -5858,6 +5902,19 @@ static struct target_ops linux_target_ops = {
   linux_get_min_fast_tracepoint_insn_len,
   linux_qxfer_libraries_svr4,
   linux_supports_agent,
+#ifdef HAVE_LINUX_BTRACE
+  linux_supports_btrace,
+  linux_low_enable_btrace,
+  linux_disable_btrace,
+  linux_btrace_has_changed,
+  linux_low_read_btrace,
+#else
+  NULL,
+  NULL,
+  NULL,
+  NULL,
+  NULL,
+#endif
 };
 
 static void
-- 
1.7.6.5