From 9183c3f9ed710a8edf1a61e8a96d497258d26e08 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Tue, 18 Aug 2020 15:57:42 +0200 Subject: static_call: Add inline static call infrastructure Add infrastructure for an arch-specific CONFIG_HAVE_STATIC_CALL_INLINE option, which is a faster version of CONFIG_HAVE_STATIC_CALL. At runtime, the static call sites are patched directly, rather than using the out-of-line trampolines. Compared to out-of-line static calls, the performance benefits are more modest, but still measurable. Steven Rostedt did some tracepoint measurements: https://lkml.kernel.org/r/20181126155405.72b4f718@gandalf.local.home This code is heavily inspired by the jump label code (aka "static jumps"), as some of the concepts are very similar. For more details, see the comments in include/linux/static_call.h. [peterz: simplified interface; merged trampolines] Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Reviewed-by: Steven Rostedt (VMware) Cc: Linus Torvalds Link: https://lore.kernel.org/r/20200818135804.684334440@infradead.org --- kernel/module.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 3c465cf31d08..c075a18103fb 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3274,6 +3274,11 @@ static int find_module_sections(struct module *mod, struct load_info *info) mod->kprobe_blacklist = section_objs(info, "_kprobe_blacklist", sizeof(unsigned long), &mod->num_kprobe_blacklist); +#endif +#ifdef CONFIG_HAVE_STATIC_CALL_INLINE + mod->static_call_sites = section_objs(info, ".static_call_sites", + sizeof(*mod->static_call_sites), + &mod->num_static_call_sites); #endif mod->extable = section_objs(info, "__ex_table", sizeof(*mod->extable), &mod->num_exentries); -- cgit v1.2.3