objtool: Move objtool_file struct off the stack

Objtool uses over 512k of stack, thanks to the hash table embedded in
the objtool_file struct.  This causes an unnecessarily large stack
allocation and breaks users with low stack limits.

Move the struct off the stack.

Fixes: 042ba73fe7eb ("objtool: Add several performance improvements")
Reported-by: Vassili Karpov <moosotc@gmail.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/df92dcbc4b84b02ffa252f46876df125fb56e2d7.1552954176.git.jpoimboe@redhat.com

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 0414a0d522621d4ca973240979e89c07d6cd4f8a..5dde107083c60bc8dd12538a2838de73c8b1470c 100644 (file)
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2184,9 +2184,10 @@ static void cleanup(struct objtool_file *file)
        elf_close(file->elf);
 }
 
+static struct objtool_file file;
+
 int check(const char *_objname, bool orc)
 {
-       struct objtool_file file;
        int ret, warnings = 0;
 
        objname = _objname;