From 0f42c1ad44d437f75b840b572376fd538fbb9643 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Mon, 21 Oct 2019 17:18:23 +0200 Subject: x86/ftrace: Get rid of function_hook History lesson courtesy of Steve: "When ftrace first was introduced to the kernel, it used gcc's mcount profiling mechanism. The mcount mechanism would add a call to "mcount" at the start of every function but after the stack frame was set up. Later, in gcc 4.6, gcc introduced -mfentry, that would create a call to "__fentry__" instead of "mcount", before the stack frame was set up. In order to handle both cases, ftrace defined a macro "function_hook" that would be either "mcount" or "__fentry__" depending on which one was being used. The Linux kernel no longer supports the "mcount" method, thus there's no reason to keep the "function_hook" define around. Simply use "__fentry__", as there is no ambiguity to the name anymore." Drop it everywhere. Signed-off-by: Borislav Petkov Acked-by: Jiri Slaby Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Jonathan Corbet Cc: Josh Poimboeuf Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Peter Zijlstra Cc: "Steven Rostedt (VMware)" Cc: Thomas Gleixner Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20191018124800.0a7006bb@gandalf.local.home --- Documentation/asm-annotations.rst | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation/asm-annotations.rst') diff --git a/Documentation/asm-annotations.rst b/Documentation/asm-annotations.rst index 29ccd6e61fe5..f55c2bb74d00 100644 --- a/Documentation/asm-annotations.rst +++ b/Documentation/asm-annotations.rst @@ -117,9 +117,9 @@ This section covers ``SYM_FUNC_*`` and ``SYM_CODE_*`` enumerated above. So in most cases, developers should write something like in the following example, having some asm instructions in between the macros, of course:: - SYM_FUNC_START(function_hook) + SYM_FUNC_START(memset) ... asm insns ... - SYM_FUNC_END(function_hook) + SYM_FUNC_END(memset) In fact, this kind of annotation corresponds to the now deprecated ``ENTRY`` and ``ENDPROC`` macros. -- cgit v1.2.3-59-g8ed1b