Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/li…

…nux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "The exciting thing here is the getting rid of stop_machine on module
  removal.  This is possible by using a simple atomic_t for the counter,
  rather than our fancy per-cpu counter: it turns out that no one is
  doing a module increment per net packet, so the slowdown should be in
  the noise"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  param: do not set store func without write perm
  params: cleanup sysfs allocation
  kernel:module Fix coding style errors and warnings.
  module: Remove stop_machine from module unloading
  module: Replace module_ref with atomic_t refcnt
  lib/bug: Use RCU list ops for module_bug_list
  module: Unlink module with RCU synchronizing instead of stop_machine
  module: Wait for RCU synchronizing before releasing a module

include/linux/module.h

@@ -210,20 +210,6 @@ enum module_state {
 	MODULE_STATE_UNFORMED,	/* Still setting it up. */
 };
 
-/**
- * struct module_ref - per cpu module reference counts
- * @incs: number of module get on this cpu
- * @decs: number of module put on this cpu
- *
- * We force an alignment on 8 or 16 bytes, so that alloc_percpu()
- * put @incs/@decs in same cache line, with no extra memory cost,
- * since alloc_percpu() is fine grained.
- */
-struct module_ref {
-	unsigned long incs;
-	unsigned long decs;
-} __attribute((aligned(2 * sizeof(unsigned long))));
-
 struct module {
 	enum module_state state;
 
@@ -367,7 +353,7 @@ struct module {
 	/* Destruction function. */
 	void (*exit)(void);
 
-	struct module_ref __percpu *refptr;
+	atomic_t refcnt;
 #endif
 
 #ifdef CONFIG_CONSTRUCTORS

include/trace/events/module.h

@@ -80,7 +80,7 @@ DECLARE_EVENT_CLASS(module_refcnt,
 
 	TP_fast_assign(
 		__entry->ip	= ip;
-		__entry->refcnt	= __this_cpu_read(mod->refptr->incs) - __this_cpu_read(mod->refptr->decs);
+		__entry->refcnt	= atomic_read(&mod->refcnt);
 		__assign_str(name, mod->name);
 	),