!214 Use __executable_start as the lowest address for profiling

From: @fangchuang
Reviewed-by: @liqingqing_1229
Signed-off-by: @liqingqing_1229

Use-__executable_start-as-the-lowest-address-for-pro.patch

@@ -0,0 +1,106 @@
+From 84a7eb1f87c1d01b58ad887a0ab5d87abbc1c772 Mon Sep 17 00:00:00 2001
+From: "H.J. Lu" <hjl.tools@gmail.com>
+Date: Fri, 30 Jul 2021 19:07:30 -0700
+Subject: [PATCH] Use __executable_start as the lowest address for profiling
+ [BZ #28153]
+
+Glibc assumes that ENTRY_POINT is the lowest address for which we need
+to keep profiling records and BFD linker uses a linker script to place
+the input sections.
+
+Starting from GCC 4.6, the main function is placed in .text.startup
+section and starting from binutils 2.22, BFD linker with
+
+commit add44f8d5c5c05e08b11e033127a744d61c26aee
+Author: Alan Modra <amodra@gmail.com>
+Date:   Thu Nov 25 03:03:02 2010 +0000
+
+            * scripttempl/elf.sc: Group .text.exit, text.startup and .text.hot
+            sections.
+
+places .text.startup section before .text section, which leave the main
+function out of profiling records.
+
+Starting from binutils 2.15, linker provides __executable_start to mark
+the lowest address of the executable.  Use __executable_start as the
+lowest address to keep the main function in profiling records. This fixes
+[BZ #28153].
+
+Tested on Linux/x86-64, Linux/x32 and Linux/i686 as well as with
+build-many-glibcs.py.
+---
+ csu/gmon-start.c              | 10 +++++++++-
+ gmon/tst-gmon-gprof.sh        |  2 ++
+ gmon/tst-gmon-static-gprof.sh |  2 ++
+ 3 files changed, 13 insertions(+), 1 deletion(-)
+
+diff --git a/csu/gmon-start.c b/csu/gmon-start.c
+index b343288..344606a 100644
+--- a/csu/gmon-start.c
++++ b/csu/gmon-start.c
+@@ -52,6 +52,11 @@ extern char ENTRY_POINT[];
+ #endif
+ extern char etext[];
+ 
++/* Use __executable_start as the lowest address to keep profiling records
++   if it provided by the linker.  */
++extern const char executable_start[] asm ("__executable_start")
++  __attribute__ ((weak, visibility ("hidden")));
++
+ #ifndef TEXT_START
+ # ifdef ENTRY_POINT_DECL
+ #  define TEXT_START ENTRY_POINT
+@@ -92,7 +97,10 @@ __gmon_start__ (void)
+   called = 1;
+ 
+   /* Start keeping profiling records.  */
+-  __monstartup ((u_long) TEXT_START, (u_long) &etext);
++  if (&executable_start != NULL)
++    __monstartup ((u_long) &executable_start, (u_long) &etext);
++  else
++    __monstartup ((u_long) TEXT_START, (u_long) &etext);
+ 
+   /* Call _mcleanup before exiting; it will write out gmon.out from the
+      collected data.  */
+diff --git a/gmon/tst-gmon-gprof.sh b/gmon/tst-gmon-gprof.sh
+index 9d37158..dc0be02 100644
+--- a/gmon/tst-gmon-gprof.sh
++++ b/gmon/tst-gmon-gprof.sh
+@@ -39,12 +39,14 @@ trap cleanup 0
+ cat > "$expected" <<EOF
+ f1 2000
+ f2 1000
++f3 1
+ EOF
+ 
+ # Special version for powerpc with function descriptors.
+ cat > "$expected_dot" <<EOF
+ .f1 2000
+ .f2 1000
++.f3 1
+ EOF
+ 
+ "$GPROF" -C "$program" "$data" \
+diff --git a/gmon/tst-gmon-static-gprof.sh b/gmon/tst-gmon-static-gprof.sh
+index 79218df..4cc99c8 100644
+--- a/gmon/tst-gmon-static-gprof.sh
++++ b/gmon/tst-gmon-static-gprof.sh
+@@ -39,6 +39,7 @@ trap cleanup 0
+ cat > "$expected" <<EOF
+ f1 2000
+ f2 1000
++f3 1
+ main 1
+ EOF
+ 
+@@ -46,6 +47,7 @@ EOF
+ cat > "$expected_dot" <<EOF
+ .f1 2000
+ .f2 1000
++.f3 1
+ .main 1
+ EOF
+ 
+-- 
+1.8.3.1
+

glibc.spec

@@ -65,7 +65,7 @@
 ##############################################################################
 Name: 	 	glibc
 Version: 	2.34
-Release: 	15
+Release: 	16
 Summary: 	The GNU libc libraries
 License:	%{all_license}
 URL: 		http://www.gnu.org/software/glibc/
@@ -116,6 +116,7 @@ Patch29: Update-string-test-memmove.c-to-cover-16KB-copy.patch
 Patch30: x86-64-Optimize-load-of-all-bits-set-into-ZMM-regist.patch
 Patch31: mtrace-Fix-output-with-PIE-and-ASLR-BZ-22716.patch
 Patch32: rtld-copy-terminating-null-in-tunables_strdup-bug-28.patch
+Patch33: Use-__executable_start-as-the-lowest-address-for-pro.patch
 
 #Patch9000: turn-REP_STOSB_THRESHOLD-from-2k-to-1M.patch
 Patch9001: delete-no-hard-link-to-avoid-all_language-package-to.patch 
@@ -1305,6 +1306,9 @@ fi
 %endif
 
 %changelog
+* Tue Oct 26 2021 Chuangchuang Fang<fangchuangchuang@huawei.com> - 2.34-16
+- Use __executable_start as the lowest address for profiling
+
 * Tue Oct 26 2021 Yang Yanchao<yangyanchao6@huawei.com> - 2.34-15
 - add glibc-compat-2.17 subpackage to provide the function of 
   the glibc-2.17 pthread library.