FROMLIST: BACKPORT: kbuild: fix dynamic ftrace with clang LTO
With CONFIG_LTO_CLANG enabled, LLVM IR won't be compiled into object
files until modpost_link. This change postpones calls to recordmcount
until after this step.
In order to exclude ftrace_process_locs from inspection, we add a new
code section .text..ftrace, which we tell recordmcount to ignore, and
a __norecordmcount attribute for moving functions to this section.
Bug: 62093296
Bug: 67506682
Change-Id: Iba2c053968206acf533fadab1eb34a743b5088ee
(am from https://patchwork.kernel.org/patch/10060327/)
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c
index 5423a58..e0c5082 100644
--- a/scripts/recordmcount.c
+++ b/scripts/recordmcount.c
@@ -366,7 +366,8 @@
strcmp(".softirqentry.text", txtname) == 0 ||
strcmp(".kprobes.text", txtname) == 0 ||
strcmp(".cpuidle.text", txtname) == 0 ||
- strcmp(".text.unlikely", txtname) == 0;
+ (strncmp(".text.", txtname, 6) == 0 &&
+ strcmp(".text..ftrace", txtname) != 0);
}
/* 32 bit and 64 bit are very similar */