Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel…

…/git/tip/linux-2.6-tip * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf stat: Fix aggreate counter reading accounting tracing: Replace syscall_meta_data struct array with pointer array tracepoints: Fix section alignment using pointer array tracing: Replace trace_event struct array with pointer array

Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel…
…/git/tip/linux-2.6-tip * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf stat: Fix aggreate counter reading accounting tracing: Replace syscall_meta_data struct array with pointer array tracepoints: Fix section alignment using pointer array tracing: Replace trace_event struct array with pointer array
Linus Torvalds
2 parents 07675f484b 862b6f62bf
Showing 11 changed files Side-by-side Diff
include/asm-generic/vmlinux.lds.h
include/linux/module.h
include/linux/syscalls.h
include/linux/tracepoint.h
include/trace/ftrace.h
kernel/module.c
kernel/trace/trace_events.c
kernel/trace/trace_export.c
kernel/trace/trace_syscalls.c
kernel/tracepoint.c
tools/perf/util/evsel.c
@@ -124,7 +124,8 @@
 #endif
  
 #ifdef CONFIG_EVENT_TRACING
-#define FTRACE_EVENTS()	VMLINUX_SYMBOL(__start_ftrace_events) = .;	\
+#define FTRACE_EVENTS()	. = ALIGN(8);					\
+			VMLINUX_SYMBOL(__start_ftrace_events) = .;	\
 			*(_ftrace_events)				\
 			VMLINUX_SYMBOL(__stop_ftrace_events) = .;
 #else
@@ -140,7 +141,8 @@
 #endif
  
 #ifdef CONFIG_FTRACE_SYSCALLS
-#define TRACE_SYSCALLS() VMLINUX_SYMBOL(__start_syscalls_metadata) = .;	\
+#define TRACE_SYSCALLS() . = ALIGN(8);					\
+			 VMLINUX_SYMBOL(__start_syscalls_metadata) = .;	\
 			 *(__syscalls_metadata)				\
 			 VMLINUX_SYMBOL(__stop_syscalls_metadata) = .;
 #else
  
@@ -165,10 +167,8 @@
 	CPU_KEEP(exit.data)						\
 	MEM_KEEP(init.data)						\
 	MEM_KEEP(exit.data)						\
-	. = ALIGN(32);							\
-	VMLINUX_SYMBOL(__start___tracepoints) = .;			\
+	STRUCT_ALIGN();							\
 	*(__tracepoints)						\
-	VMLINUX_SYMBOL(__stop___tracepoints) = .;			\
 	/* implement dynamic printk debug */				\
 	. = ALIGN(8);							\
 	VMLINUX_SYMBOL(__start___verbose) = .;                          \
@@ -176,13 +176,7 @@
 	VMLINUX_SYMBOL(__stop___verbose) = .;				\
 	LIKELY_PROFILE()		       				\
 	BRANCH_PROFILE()						\
-	TRACE_PRINTKS()							\
-									\
-	STRUCT_ALIGN();							\
-	FTRACE_EVENTS()							\
-									\
-	STRUCT_ALIGN();							\
-	TRACE_SYSCALLS()
+	TRACE_PRINTKS()
  
 /*
  * Data section helpers
@@ -220,6 +214,10 @@
 		VMLINUX_SYMBOL(__start_rodata) = .;			\
 		*(.rodata) *(.rodata.*)					\
 		*(__vermagic)		/* Kernel version magic */	\
+		. = ALIGN(8);						\
+		VMLINUX_SYMBOL(__start___tracepoints_ptrs) = .;		\
+		*(__tracepoints_ptrs)	/* Tracepoints: pointer array */\
+		VMLINUX_SYMBOL(__stop___tracepoints_ptrs) = .;		\
 		*(__markers_strings)	/* Markers: strings */		\
 		*(__tracepoints_strings)/* Tracepoints: strings */	\
 	}								\
@@ -482,6 +480,8 @@
 	KERNEL_CTORS()							\
 	*(.init.rodata)							\
 	MCOUNT_REC()							\
+	FTRACE_EVENTS()							\
+	TRACE_SYSCALLS()						\
 	DEV_DISCARD(init.rodata)					\
 	CPU_DISCARD(init.rodata)					\
 	MEM_DISCARD(init.rodata)					\
@@ -377,7 +377,7 @@
 	   keeping pointers to this stuff */
 	char *args;
 #ifdef CONFIG_TRACEPOINTS
-	struct tracepoint *tracepoints;
+	struct tracepoint * const *tracepoints_ptrs;
 	unsigned int num_tracepoints;
 #endif
 #ifdef HAVE_JUMP_LABEL
@@ -389,7 +389,7 @@
 	unsigned int num_trace_bprintk_fmt;
 #endif
 #ifdef CONFIG_EVENT_TRACING
-	struct ftrace_event_call *trace_events;
+	struct ftrace_event_call **trace_events;
 	unsigned int num_trace_events;
 #endif
 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
@@ -125,39 +125,37 @@
 extern struct trace_event_functions exit_syscall_print_funcs;
  
 #define SYSCALL_TRACE_ENTER_EVENT(sname)				\
-	static struct syscall_metadata					\
-	__attribute__((__aligned__(4))) __syscall_meta_##sname;		\
+	static struct syscall_metadata __syscall_meta_##sname;		\
 	static struct ftrace_event_call __used				\
-	  __attribute__((__aligned__(4)))				\
-	  __attribute__((section("_ftrace_events")))			\
 	  event_enter_##sname = {					\
 		.name                   = "sys_enter"#sname,		\
 		.class			= &event_class_syscall_enter,	\
 		.event.funcs            = &enter_syscall_print_funcs,	\
 		.data			= (void *)&__syscall_meta_##sname,\
 	};								\
+	static struct ftrace_event_call __used				\
+	  __attribute__((section("_ftrace_events")))			\
+	 *__event_enter_##sname = &event_enter_##sname;			\
 	__TRACE_EVENT_FLAGS(enter_##sname, TRACE_EVENT_FL_CAP_ANY)
  
 #define SYSCALL_TRACE_EXIT_EVENT(sname)					\
-	static struct syscall_metadata					\
-	__attribute__((__aligned__(4))) __syscall_meta_##sname;		\
+	static struct syscall_metadata __syscall_meta_##sname;		\
 	static struct ftrace_event_call __used				\
-	  __attribute__((__aligned__(4)))				\
-	  __attribute__((section("_ftrace_events")))			\
 	  event_exit_##sname = {					\
 		.name                   = "sys_exit"#sname,		\
 		.class			= &event_class_syscall_exit,	\
 		.event.funcs		= &exit_syscall_print_funcs,	\
 		.data			= (void *)&__syscall_meta_##sname,\
 	};								\
+	static struct ftrace_event_call __used				\
+	  __attribute__((section("_ftrace_events")))			\
+	*__event_exit_##sname = &event_exit_##sname;			\
 	__TRACE_EVENT_FLAGS(exit_##sname, TRACE_EVENT_FL_CAP_ANY)
  
 #define SYSCALL_METADATA(sname, nb)				\
 	SYSCALL_TRACE_ENTER_EVENT(sname);			\
 	SYSCALL_TRACE_EXIT_EVENT(sname);			\
 	static struct syscall_metadata __used			\
-	  __attribute__((__aligned__(4)))			\
-	  __attribute__((section("__syscalls_metadata")))	\
 	  __syscall_meta_##sname = {				\
 		.name 		= "sys"#sname,			\
 		.nb_args 	= nb,				\
  
@@ -166,14 +164,15 @@
 		.enter_event	= &event_enter_##sname,		\
 		.exit_event	= &event_exit_##sname,		\
 		.enter_fields	= LIST_HEAD_INIT(__syscall_meta_##sname.enter_fields), \
-	};
+	};							\
+	static struct syscall_metadata __used			\
+	  __attribute__((section("__syscalls_metadata")))	\
+	 *__p_syscall_meta_##sname = &__syscall_meta_##sname;
  
 #define SYSCALL_DEFINE0(sname)					\
 	SYSCALL_TRACE_ENTER_EVENT(_##sname);			\
 	SYSCALL_TRACE_EXIT_EVENT(_##sname);			\
 	static struct syscall_metadata __used			\
-	  __attribute__((__aligned__(4)))			\
-	  __attribute__((section("__syscalls_metadata")))	\
 	  __syscall_meta__##sname = {				\
 		.name 		= "sys_"#sname,			\
 		.nb_args 	= 0,				\
@@ -181,6 +180,9 @@
 		.exit_event	= &event_exit__##sname,		\
 		.enter_fields	= LIST_HEAD_INIT(__syscall_meta__##sname.enter_fields), \
 	};							\
+	static struct syscall_metadata __used			\
+	  __attribute__((section("__syscalls_metadata")))	\
+	 *__p_syscall_meta_##sname = &__syscall_meta__##sname;	\
 	asmlinkage long sys_##sname(void)
 #else
 #define SYSCALL_DEFINE0(name)	   asmlinkage long sys_##name(void)
@@ -33,12 +33,7 @@
 	void (*regfunc)(void);
 	void (*unregfunc)(void);
 	struct tracepoint_func __rcu *funcs;
-} __attribute__((aligned(32)));		/*
-					 * Aligned on 32 bytes because it is
-					 * globally visible and gcc happily
-					 * align these on the structure size.
-					 * Keep in sync with vmlinux.lds.h.
-					 */
+};
  
 /*
  * Connect a probe to a tracepoint.
  
@@ -61,15 +56,15 @@
  
 struct tracepoint_iter {
 	struct module *module;
-	struct tracepoint *tracepoint;
+	struct tracepoint * const *tracepoint;
 };
  
 extern void tracepoint_iter_start(struct tracepoint_iter *iter);
 extern void tracepoint_iter_next(struct tracepoint_iter *iter);
 extern void tracepoint_iter_stop(struct tracepoint_iter *iter);
 extern void tracepoint_iter_reset(struct tracepoint_iter *iter);
-extern int tracepoint_get_iter_range(struct tracepoint **tracepoint,
-	struct tracepoint *begin, struct tracepoint *end);
+extern int tracepoint_get_iter_range(struct tracepoint * const **tracepoint,
+	struct tracepoint * const *begin, struct tracepoint * const *end);
  
 /*
  * tracepoint_synchronize_unregister must be called between the last tracepoint
  
@@ -84,11 +79,13 @@
 #define PARAMS(args...) args
  
 #ifdef CONFIG_TRACEPOINTS
-extern void tracepoint_update_probe_range(struct tracepoint *begin,
-	struct tracepoint *end);
+extern
+void tracepoint_update_probe_range(struct tracepoint * const *begin,
+	struct tracepoint * const *end);
 #else
-static inline void tracepoint_update_probe_range(struct tracepoint *begin,
-	struct tracepoint *end)
+static inline
+void tracepoint_update_probe_range(struct tracepoint * const *begin,
+	struct tracepoint * const *end)
 { }
 #endif /* CONFIG_TRACEPOINTS */
  
  
@@ -174,12 +171,20 @@
 	{								\
 	}
  
+/*
+ * We have no guarantee that gcc and the linker won't up-align the tracepoint
+ * structures, so we create an array of pointers that will be used for iteration
+ * on the tracepoints.
+ */
 #define DEFINE_TRACE_FN(name, reg, unreg)				\
 	static const char __tpstrtab_##name[]				\
 	__attribute__((section("__tracepoints_strings"))) = #name;	\
 	struct tracepoint __tracepoint_##name				\
-	__attribute__((section("__tracepoints"), aligned(32))) =	\
-		{ __tpstrtab_##name, 0, reg, unreg, NULL }
+	__attribute__((section("__tracepoints"))) =			\
+		{ __tpstrtab_##name, 0, reg, unreg, NULL };		\
+	static struct tracepoint * const __tracepoint_ptr_##name __used	\
+	__attribute__((section("__tracepoints_ptrs"))) =		\
+		&__tracepoint_##name;
  
 #define DEFINE_TRACE(name)						\
 	DEFINE_TRACE_FN(name, NULL, NULL);
@@ -446,14 +446,16 @@
  *	.reg			= ftrace_event_reg,
  * };
  *
- * static struct ftrace_event_call __used
- * __attribute__((__aligned__(4)))
- * __attribute__((section("_ftrace_events"))) event_<call> = {
+ * static struct ftrace_event_call event_<call> = {
  *	.name			= "<call>",
  *	.class			= event_class_<template>,
  *	.event			= &ftrace_event_type_<call>,
  *	.print_fmt		= print_fmt_<call>,
  * };
+ * // its only safe to use pointers when doing linker tricks to
+ * // create an array.
+ * static struct ftrace_event_call __used
+ * __attribute__((section("_ftrace_events"))) *__event_<call> = &event_<call>;
  *
  */
  
  
  
  
@@ -579,28 +581,28 @@
 #undef DEFINE_EVENT
 #define DEFINE_EVENT(template, call, proto, args)			\
 									\
-static struct ftrace_event_call __used					\
-__attribute__((__aligned__(4)))						\
-__attribute__((section("_ftrace_events"))) event_##call = {		\
+static struct ftrace_event_call __used event_##call = {			\
 	.name			= #call,				\
 	.class			= &event_class_##template,		\
 	.event.funcs		= &ftrace_event_type_funcs_##template,	\
 	.print_fmt		= print_fmt_##template,			\
-};
+};									\
+static struct ftrace_event_call __used					\
+__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
  
 #undef DEFINE_EVENT_PRINT
 #define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
 									\
 static const char print_fmt_##call[] = print;				\
 									\
-static struct ftrace_event_call __used					\
-__attribute__((__aligned__(4)))						\
-__attribute__((section("_ftrace_events"))) event_##call = {		\
+static struct ftrace_event_call __used event_##call = {			\
 	.name			= #call,				\
 	.class			= &event_class_##template,		\
 	.event.funcs		= &ftrace_event_type_funcs_##call,	\
 	.print_fmt		= print_fmt_##call,			\
-}
+};									\
+static struct ftrace_event_call __used					\
+__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
  
 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
  
@@ -2460,9 +2460,9 @@
 #endif
  
 #ifdef CONFIG_TRACEPOINTS
-	mod->tracepoints = section_objs(info, "__tracepoints",
-					sizeof(*mod->tracepoints),
-					&mod->num_tracepoints);
+	mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
+					     sizeof(*mod->tracepoints_ptrs),
+					     &mod->num_tracepoints);
 #endif
 #ifdef HAVE_JUMP_LABEL
 	mod->jump_entries = section_objs(info, "__jump_table",
@@ -3393,7 +3393,7 @@
 		   struct modversion_info *ver,
 		   struct kernel_param *kp,
 		   struct kernel_symbol *ks,
-		   struct tracepoint *tp)
+		   struct tracepoint * const *tp)
 {
 }
 EXPORT_SYMBOL(module_layout);
@@ -3407,8 +3407,8 @@
 	mutex_lock(&module_mutex);
 	list_for_each_entry(mod, &modules, list)
 		if (!mod->taints)
-			tracepoint_update_probe_range(mod->tracepoints,
-				mod->tracepoints + mod->num_tracepoints);
+			tracepoint_update_probe_range(mod->tracepoints_ptrs,
+				mod->tracepoints_ptrs + mod->num_tracepoints);
 	mutex_unlock(&module_mutex);
 }
  
@@ -3432,8 +3432,8 @@
 			else if (iter_mod > iter->module)
 				iter->tracepoint = NULL;
 			found = tracepoint_get_iter_range(&iter->tracepoint,
-				iter_mod->tracepoints,
-				iter_mod->tracepoints
+				iter_mod->tracepoints_ptrs,
+				iter_mod->tracepoints_ptrs
 					+ iter_mod->num_tracepoints);
 			if (found) {
 				iter->module = iter_mod;
@@ -1284,7 +1284,7 @@
 static void trace_module_add_events(struct module *mod)
 {
 	struct ftrace_module_file_ops *file_ops = NULL;
-	struct ftrace_event_call *call, *start, *end;
+	struct ftrace_event_call **call, **start, **end;
  
 	start = mod->trace_events;
 	end = mod->trace_events + mod->num_trace_events;
@@ -1297,7 +1297,7 @@
 		return;
  
 	for_each_event(call, start, end) {
-		__trace_add_event_call(call, mod,
+		__trace_add_event_call(*call, mod,
 				       &file_ops->id, &file_ops->enable,
 				       &file_ops->filter, &file_ops->format);
 	}
@@ -1367,8 +1367,8 @@
 	.priority = 0,
 };
  
-extern struct ftrace_event_call __start_ftrace_events[];
-extern struct ftrace_event_call __stop_ftrace_events[];
+extern struct ftrace_event_call *__start_ftrace_events[];
+extern struct ftrace_event_call *__stop_ftrace_events[];
  
 static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
  
@@ -1384,7 +1384,7 @@
  
 static __init int event_trace_init(void)
 {
-	struct ftrace_event_call *call;
+	struct ftrace_event_call **call;
 	struct dentry *d_tracer;
 	struct dentry *entry;
 	struct dentry *d_events;
@@ -1430,7 +1430,7 @@
 		pr_warning("tracing: Failed to allocate common fields");
  
 	for_each_event(call, __start_ftrace_events, __stop_ftrace_events) {
-		__trace_add_event_call(call, NULL, &ftrace_event_id_fops,
+		__trace_add_event_call(*call, NULL, &ftrace_event_id_fops,
 				       &ftrace_enable_fops,
 				       &ftrace_event_filter_fops,
 				       &ftrace_event_format_fops);
@@ -161,14 +161,14 @@
 	.fields			= LIST_HEAD_INIT(event_class_ftrace_##call.fields),\
 };									\
 									\
-struct ftrace_event_call __used						\
-__attribute__((__aligned__(4)))						\
-__attribute__((section("_ftrace_events"))) event_##call = {		\
+struct ftrace_event_call __used event_##call = {			\
 	.name			= #call,				\
 	.event.type		= etype,				\
 	.class			= &event_class_ftrace_##call,		\
 	.print_fmt		= print,				\
 };									\
+struct ftrace_event_call __used						\
+__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call;
  
 #include "trace_entries.h"
@@ -55,20 +55,21 @@
 	.raw_init	= init_syscall_trace,
 };
  
-extern unsigned long __start_syscalls_metadata[];
-extern unsigned long __stop_syscalls_metadata[];
+extern struct syscall_metadata *__start_syscalls_metadata[];
+extern struct syscall_metadata *__stop_syscalls_metadata[];
  
 static struct syscall_metadata **syscalls_metadata;
  
-static struct syscall_metadata *find_syscall_meta(unsigned long syscall)
+static __init struct syscall_metadata *
+find_syscall_meta(unsigned long syscall)
 {
-	struct syscall_metadata *start;
-	struct syscall_metadata *stop;
+	struct syscall_metadata **start;
+	struct syscall_metadata **stop;
 	char str[KSYM_SYMBOL_LEN];
  
  
-	start = (struct syscall_metadata *)__start_syscalls_metadata;
-	stop = (struct syscall_metadata *)__stop_syscalls_metadata;
+	start = __start_syscalls_metadata;
+	stop = __stop_syscalls_metadata;
 	kallsyms_lookup(syscall, NULL, NULL, NULL, str);
  
 	for ( ; start < stop; start++) {
@@ -78,8 +79,8 @@
 		 * with "SyS" instead of "sys", leading to an unwanted
 		 * mismatch.
 		 */
-		if (start->name && !strcmp(start->name + 3, str + 3))
-			return start;
+		if ((*start)->name && !strcmp((*start)->name + 3, str + 3))
+			return *start;
 	}
 	return NULL;
 }
@@ -27,8 +27,8 @@
 #include <linux/sched.h>
 #include <linux/jump_label.h>
  
-extern struct tracepoint __start___tracepoints[];
-extern struct tracepoint __stop___tracepoints[];
+extern struct tracepoint * const __start___tracepoints_ptrs[];
+extern struct tracepoint * const __stop___tracepoints_ptrs[];
  
 /* Set to 1 to enable tracepoint debug output */
 static const int tracepoint_debug;
  
@@ -298,10 +298,10 @@
  *
  * Updates the probe callback corresponding to a range of tracepoints.
  */
-void
-tracepoint_update_probe_range(struct tracepoint *begin, struct tracepoint *end)
+void tracepoint_update_probe_range(struct tracepoint * const *begin,
+				   struct tracepoint * const *end)
 {
-	struct tracepoint *iter;
+	struct tracepoint * const *iter;
 	struct tracepoint_entry *mark_entry;
  
 	if (!begin)
  
  
@@ -309,12 +309,12 @@
  
 	mutex_lock(&tracepoints_mutex);
 	for (iter = begin; iter < end; iter++) {
-		mark_entry = get_tracepoint(iter->name);
+		mark_entry = get_tracepoint((*iter)->name);
 		if (mark_entry) {
-			set_tracepoint(&mark_entry, iter,
+			set_tracepoint(&mark_entry, *iter,
 					!!mark_entry->refcount);
 		} else {
-			disable_tracepoint(iter);
+			disable_tracepoint(*iter);
 		}
 	}
 	mutex_unlock(&tracepoints_mutex);
@@ -326,8 +326,8 @@
 static void tracepoint_update_probes(void)
 {
 	/* Core kernel tracepoints */
-	tracepoint_update_probe_range(__start___tracepoints,
-		__stop___tracepoints);
+	tracepoint_update_probe_range(__start___tracepoints_ptrs,
+		__stop___tracepoints_ptrs);
 	/* tracepoints in modules. */
 	module_update_tracepoints();
 }
@@ -514,8 +514,8 @@
  * Will return the first tracepoint in the range if the input tracepoint is
  * NULL.
  */
-int tracepoint_get_iter_range(struct tracepoint **tracepoint,
-	struct tracepoint *begin, struct tracepoint *end)
+int tracepoint_get_iter_range(struct tracepoint * const **tracepoint,
+	struct tracepoint * const *begin, struct tracepoint * const *end)
 {
 	if (!*tracepoint && begin != end) {
 		*tracepoint = begin;
@@ -534,7 +534,8 @@
 	/* Core kernel tracepoints */
 	if (!iter->module) {
 		found = tracepoint_get_iter_range(&iter->tracepoint,
-				__start___tracepoints, __stop___tracepoints);
+				__start___tracepoints_ptrs,
+				__stop___tracepoints_ptrs);
 		if (found)
 			goto end;
 	}
@@ -585,8 +586,8 @@
 	switch (val) {
 	case MODULE_STATE_COMING:
 	case MODULE_STATE_GOING:
-		tracepoint_update_probe_range(mod->tracepoints,
-			mod->tracepoints + mod->num_tracepoints);
+		tracepoint_update_probe_range(mod->tracepoints_ptrs,
+			mod->tracepoints_ptrs + mod->num_tracepoints);
 		break;
 	}
 	return 0;
@@ -90,7 +90,7 @@
 	int cpu, thread;
 	struct perf_counts_values *aggr = &evsel->counts->aggr, count;
  
-	aggr->val = 0;
+	aggr->val = aggr->ena = aggr->run = 0;
  
 	for (cpu = 0; cpu < ncpus; cpu++) {
 		for (thread = 0; thread < nthreads; thread++) {
...	...	@@ -124,7 +124,8 @@
124	124	#endif
125	125
126	126	#ifdef CONFIG_EVENT_TRACING
127		-#define FTRACE_EVENTS() VMLINUX_SYMBOL(__start_ftrace_events) = .; \
	127	+#define FTRACE_EVENTS() . = ALIGN(8); \
	128	+ VMLINUX_SYMBOL(__start_ftrace_events) = .; \
128	129	*(_ftrace_events) \
129	130	VMLINUX_SYMBOL(__stop_ftrace_events) = .;
130	131	#else
...	...	@@ -140,7 +141,8 @@
140	141	#endif
141	142
142	143	#ifdef CONFIG_FTRACE_SYSCALLS
143		-#define TRACE_SYSCALLS() VMLINUX_SYMBOL(__start_syscalls_metadata) = .; \
	144	+#define TRACE_SYSCALLS() . = ALIGN(8); \
	145	+ VMLINUX_SYMBOL(__start_syscalls_metadata) = .; \
144	146	*(__syscalls_metadata) \
145	147	VMLINUX_SYMBOL(__stop_syscalls_metadata) = .;
146	148	#else
147	149
...	...	@@ -165,10 +167,8 @@
165	167	CPU_KEEP(exit.data) \
166	168	MEM_KEEP(init.data) \
167	169	MEM_KEEP(exit.data) \
168		- . = ALIGN(32); \
169		- VMLINUX_SYMBOL(__start___tracepoints) = .; \
	170	+ STRUCT_ALIGN(); \
170	171	*(__tracepoints) \
171		- VMLINUX_SYMBOL(__stop___tracepoints) = .; \
172	172	/* implement dynamic printk debug */ \
173	173	. = ALIGN(8); \
174	174	VMLINUX_SYMBOL(__start___verbose) = .; \
...	...	@@ -176,13 +176,7 @@
176	176	VMLINUX_SYMBOL(__stop___verbose) = .; \
177	177	LIKELY_PROFILE() \
178	178	BRANCH_PROFILE() \
179		- TRACE_PRINTKS() \
180		- \
181		- STRUCT_ALIGN(); \
182		- FTRACE_EVENTS() \
183		- \
184		- STRUCT_ALIGN(); \
185		- TRACE_SYSCALLS()
	179	+ TRACE_PRINTKS()
186	180
187	181	/*
188	182	* Data section helpers
...	...	@@ -220,6 +214,10 @@
220	214	VMLINUX_SYMBOL(__start_rodata) = .; \
221	215	(.rodata) (.rodata.*) \
222	216	(__vermagic) / Kernel version magic */ \
	217	+ . = ALIGN(8); \
	218	+ VMLINUX_SYMBOL(__start___tracepoints_ptrs) = .; \
	219	+ (__tracepoints_ptrs) / Tracepoints: pointer array */\
	220	+ VMLINUX_SYMBOL(__stop___tracepoints_ptrs) = .; \
223	221	(__markers_strings) / Markers: strings */ \
224	222	(__tracepoints_strings)/ Tracepoints: strings */ \
225	223	} \
...	...	@@ -482,6 +480,8 @@
482	480	KERNEL_CTORS() \
483	481	*(.init.rodata) \
484	482	MCOUNT_REC() \
	483	+ FTRACE_EVENTS() \
	484	+ TRACE_SYSCALLS() \
485	485	DEV_DISCARD(init.rodata) \
486	486	CPU_DISCARD(init.rodata) \
487	487	MEM_DISCARD(init.rodata) \
...	...	@@ -377,7 +377,7 @@
377	377	keeping pointers to this stuff */
378	378	char *args;
379	379	#ifdef CONFIG_TRACEPOINTS
380		- struct tracepoint *tracepoints;
	380	+ struct tracepoint * const *tracepoints_ptrs;
381	381	unsigned int num_tracepoints;
382	382	#endif
383	383	#ifdef HAVE_JUMP_LABEL
...	...	@@ -389,7 +389,7 @@
389	389	unsigned int num_trace_bprintk_fmt;
390	390	#endif
391	391	#ifdef CONFIG_EVENT_TRACING
392		- struct ftrace_event_call *trace_events;
	392	+ struct ftrace_event_call **trace_events;
393	393	unsigned int num_trace_events;
394	394	#endif
395	395	#ifdef CONFIG_FTRACE_MCOUNT_RECORD
...	...	@@ -125,39 +125,37 @@
125	125	extern struct trace_event_functions exit_syscall_print_funcs;
126	126
127	127	#define SYSCALL_TRACE_ENTER_EVENT(sname) \
128		- static struct syscall_metadata \
129		- __attribute__((__aligned__(4))) __syscall_meta_##sname; \
	128	+ static struct syscall_metadata __syscall_meta_##sname; \
130	129	static struct ftrace_event_call __used \
131		- __attribute__((__aligned__(4))) \
132		- __attribute__((section("_ftrace_events"))) \
133	130	event_enter_##sname = { \
134	131	.name = "sys_enter"#sname, \
135	132	.class = &event_class_syscall_enter, \
136	133	.event.funcs = &enter_syscall_print_funcs, \
137	134	.data = (void *)&__syscall_meta_##sname,\
138	135	}; \
	136	+ static struct ftrace_event_call __used \
	137	+ __attribute__((section("_ftrace_events"))) \
	138	+ *__event_enter_##sname = &event_enter_##sname; \
139	139	__TRACE_EVENT_FLAGS(enter_##sname, TRACE_EVENT_FL_CAP_ANY)
140	140
141	141	#define SYSCALL_TRACE_EXIT_EVENT(sname) \
142		- static struct syscall_metadata \
143		- __attribute__((__aligned__(4))) __syscall_meta_##sname; \
	142	+ static struct syscall_metadata __syscall_meta_##sname; \
144	143	static struct ftrace_event_call __used \
145		- __attribute__((__aligned__(4))) \
146		- __attribute__((section("_ftrace_events"))) \
147	144	event_exit_##sname = { \
148	145	.name = "sys_exit"#sname, \
149	146	.class = &event_class_syscall_exit, \
150	147	.event.funcs = &exit_syscall_print_funcs, \
151	148	.data = (void *)&__syscall_meta_##sname,\
152	149	}; \
	150	+ static struct ftrace_event_call __used \
	151	+ __attribute__((section("_ftrace_events"))) \
	152	+ *__event_exit_##sname = &event_exit_##sname; \
153	153	__TRACE_EVENT_FLAGS(exit_##sname, TRACE_EVENT_FL_CAP_ANY)
154	154
155	155	#define SYSCALL_METADATA(sname, nb) \
156	156	SYSCALL_TRACE_ENTER_EVENT(sname); \
157	157	SYSCALL_TRACE_EXIT_EVENT(sname); \
158	158	static struct syscall_metadata __used \
159		- __attribute__((__aligned__(4))) \
160		- __attribute__((section("__syscalls_metadata"))) \
161	159	__syscall_meta_##sname = { \
162	160	.name = "sys"#sname, \
163	161	.nb_args = nb, \
164	162
...	...	@@ -166,14 +164,15 @@
166	164	.enter_event = &event_enter_##sname, \
167	165	.exit_event = &event_exit_##sname, \
168	166	.enter_fields = LIST_HEAD_INIT(__syscall_meta_##sname.enter_fields), \
169		- };
	167	+ }; \
	168	+ static struct syscall_metadata __used \
	169	+ __attribute__((section("__syscalls_metadata"))) \
	170	+ *__p_syscall_meta_##sname = &__syscall_meta_##sname;
170	171
171	172	#define SYSCALL_DEFINE0(sname) \
172	173	SYSCALL_TRACE_ENTER_EVENT(_##sname); \
173	174	SYSCALL_TRACE_EXIT_EVENT(_##sname); \
174	175	static struct syscall_metadata __used \
175		- __attribute__((__aligned__(4))) \
176		- __attribute__((section("__syscalls_metadata"))) \
177	176	__syscall_meta__##sname = { \
178	177	.name = "sys_"#sname, \
179	178	.nb_args = 0, \
...	...	@@ -181,6 +180,9 @@
181	180	.exit_event = &event_exit__##sname, \
182	181	.enter_fields = LIST_HEAD_INIT(__syscall_meta__##sname.enter_fields), \
183	182	}; \
	183	+ static struct syscall_metadata __used \
	184	+ __attribute__((section("__syscalls_metadata"))) \
	185	+ *__p_syscall_meta_##sname = &__syscall_meta__##sname; \
184	186	asmlinkage long sys_##sname(void)
185	187	#else
186	188	#define SYSCALL_DEFINE0(name) asmlinkage long sys_##name(void)
...	...	@@ -33,12 +33,7 @@
33	33	void (*regfunc)(void);
34	34	void (*unregfunc)(void);
35	35	struct tracepoint_func __rcu *funcs;
36		-} __attribute__((aligned(32))); /*
37		- * Aligned on 32 bytes because it is
38		- * globally visible and gcc happily
39		- * align these on the structure size.
40		- * Keep in sync with vmlinux.lds.h.
41		- */
	36	+};
42	37
43	38	/*
44	39	* Connect a probe to a tracepoint.
45	40
...	...	@@ -61,15 +56,15 @@
61	56
62	57	struct tracepoint_iter {
63	58	struct module *module;
64		- struct tracepoint *tracepoint;
	59	+ struct tracepoint * const *tracepoint;
65	60	};
66	61
67	62	extern void tracepoint_iter_start(struct tracepoint_iter *iter);
68	63	extern void tracepoint_iter_next(struct tracepoint_iter *iter);
69	64	extern void tracepoint_iter_stop(struct tracepoint_iter *iter);
70	65	extern void tracepoint_iter_reset(struct tracepoint_iter *iter);
71		-extern int tracepoint_get_iter_range(struct tracepoint **tracepoint,
72		- struct tracepoint begin, struct tracepoint end);
	66	+extern int tracepoint_get_iter_range(struct tracepoint * const **tracepoint,
	67	+ struct tracepoint * const begin, struct tracepoint const *end);
73	68
74	69	/*
75	70	* tracepoint_synchronize_unregister must be called between the last tracepoint
76	71
...	...	@@ -84,11 +79,13 @@
84	79	#define PARAMS(args...) args
85	80
86	81	#ifdef CONFIG_TRACEPOINTS
87		-extern void tracepoint_update_probe_range(struct tracepoint *begin,
88		- struct tracepoint *end);
	82	+extern
	83	+void tracepoint_update_probe_range(struct tracepoint * const *begin,
	84	+ struct tracepoint * const *end);
89	85	#else
90		-static inline void tracepoint_update_probe_range(struct tracepoint *begin,
91		- struct tracepoint *end)
	86	+static inline
	87	+void tracepoint_update_probe_range(struct tracepoint * const *begin,
	88	+ struct tracepoint * const *end)
92	89	{ }
93	90	#endif /* CONFIG_TRACEPOINTS */
94	91
95	92
...	...	@@ -174,12 +171,20 @@
174	171	{ \
175	172	}
176	173
	174	+/*
	175	+ * We have no guarantee that gcc and the linker won't up-align the tracepoint
	176	+ * structures, so we create an array of pointers that will be used for iteration
	177	+ * on the tracepoints.
	178	+ */
177	179	#define DEFINE_TRACE_FN(name, reg, unreg) \
178	180	static const char __tpstrtab_##name[] \
179	181	__attribute__((section("__tracepoints_strings"))) = #name; \
180	182	struct tracepoint __tracepoint_##name \
181		- __attribute__((section("__tracepoints"), aligned(32))) = \
182		- { __tpstrtab_##name, 0, reg, unreg, NULL }
	183	+ __attribute__((section("__tracepoints"))) = \
	184	+ { __tpstrtab_##name, 0, reg, unreg, NULL }; \
	185	+ static struct tracepoint * const __tracepoint_ptr_##name __used \
	186	+ __attribute__((section("__tracepoints_ptrs"))) = \
	187	+ &__tracepoint_##name;
183	188
184	189	#define DEFINE_TRACE(name) \
185	190	DEFINE_TRACE_FN(name, NULL, NULL);
...	...	@@ -446,14 +446,16 @@
446	446	* .reg = ftrace_event_reg,
447	447	* };
448	448	*
449		- * static struct ftrace_event_call __used
450		- * __attribute__((__aligned__(4)))
451		- * __attribute__((section("_ftrace_events"))) event_<call> = {
	449	+ * static struct ftrace_event_call event_<call> = {
452	450	* .name = "<call>",
453	451	* .class = event_class_<template>,
454	452	* .event = &ftrace_event_type_<call>,
455	453	* .print_fmt = print_fmt_<call>,
456	454	* };
	455	+ * // its only safe to use pointers when doing linker tricks to
	456	+ * // create an array.
	457	+ * static struct ftrace_event_call __used
	458	+ * __attribute__((section("_ftrace_events"))) *__event_<call> = &event_<call>;
457	459	*
458	460	*/
459	461
460	462
461	463
462	464
...	...	@@ -579,28 +581,28 @@
579	581	#undef DEFINE_EVENT
580	582	#define DEFINE_EVENT(template, call, proto, args) \
581	583	\
582		-static struct ftrace_event_call __used \
583		-__attribute__((__aligned__(4))) \
584		-__attribute__((section("_ftrace_events"))) event_##call = { \
	584	+static struct ftrace_event_call __used event_##call = { \
585	585	.name = #call, \
586	586	.class = &event_class_##template, \
587	587	.event.funcs = &ftrace_event_type_funcs_##template, \
588	588	.print_fmt = print_fmt_##template, \
589		-};
	589	+}; \
	590	+static struct ftrace_event_call __used \
	591	+__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
590	592
591	593	#undef DEFINE_EVENT_PRINT
592	594	#define DEFINE_EVENT_PRINT(template, call, proto, args, print) \
593	595	\
594	596	static const char print_fmt_##call[] = print; \
595	597	\
596		-static struct ftrace_event_call __used \
597		-__attribute__((__aligned__(4))) \
598		-__attribute__((section("_ftrace_events"))) event_##call = { \
	598	+static struct ftrace_event_call __used event_##call = { \
599	599	.name = #call, \
600	600	.class = &event_class_##template, \
601	601	.event.funcs = &ftrace_event_type_funcs_##call, \
602	602	.print_fmt = print_fmt_##call, \
603		-}
	603	+}; \
	604	+static struct ftrace_event_call __used \
	605	+__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
604	606
605	607	#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
606	608
...	...	@@ -2460,9 +2460,9 @@
2460	2460	#endif
2461	2461
2462	2462	#ifdef CONFIG_TRACEPOINTS
2463		- mod->tracepoints = section_objs(info, "__tracepoints",
2464		- sizeof(*mod->tracepoints),
2465		- &mod->num_tracepoints);
	2463	+ mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
	2464	+ sizeof(*mod->tracepoints_ptrs),
	2465	+ &mod->num_tracepoints);
2466	2466	#endif
2467	2467	#ifdef HAVE_JUMP_LABEL
2468	2468	mod->jump_entries = section_objs(info, "__jump_table",
...	...	@@ -3393,7 +3393,7 @@
3393	3393	struct modversion_info *ver,
3394	3394	struct kernel_param *kp,
3395	3395	struct kernel_symbol *ks,
3396		- struct tracepoint *tp)
	3396	+ struct tracepoint * const *tp)
3397	3397	{
3398	3398	}
3399	3399	EXPORT_SYMBOL(module_layout);
...	...	@@ -3407,8 +3407,8 @@
3407	3407	mutex_lock(&module_mutex);
3408	3408	list_for_each_entry(mod, &modules, list)
3409	3409	if (!mod->taints)
3410		- tracepoint_update_probe_range(mod->tracepoints,
3411		- mod->tracepoints + mod->num_tracepoints);
	3410	+ tracepoint_update_probe_range(mod->tracepoints_ptrs,
	3411	+ mod->tracepoints_ptrs + mod->num_tracepoints);
3412	3412	mutex_unlock(&module_mutex);
3413	3413	}
3414	3414
...	...	@@ -3432,8 +3432,8 @@
3432	3432	else if (iter_mod > iter->module)
3433	3433	iter->tracepoint = NULL;
3434	3434	found = tracepoint_get_iter_range(&iter->tracepoint,
3435		- iter_mod->tracepoints,
3436		- iter_mod->tracepoints
	3435	+ iter_mod->tracepoints_ptrs,
	3436	+ iter_mod->tracepoints_ptrs
3437	3437	+ iter_mod->num_tracepoints);
3438	3438	if (found) {
3439	3439	iter->module = iter_mod;
...	...	@@ -1284,7 +1284,7 @@
1284	1284	static void trace_module_add_events(struct module *mod)
1285	1285	{
1286	1286	struct ftrace_module_file_ops *file_ops = NULL;
1287		- struct ftrace_event_call call, start, *end;
	1287	+ struct ftrace_event_call call, start, **end;
1288	1288
1289	1289	start = mod->trace_events;
1290	1290	end = mod->trace_events + mod->num_trace_events;
...	...	@@ -1297,7 +1297,7 @@
1297	1297	return;
1298	1298
1299	1299	for_each_event(call, start, end) {
1300		- __trace_add_event_call(call, mod,
	1300	+ __trace_add_event_call(*call, mod,
1301	1301	&file_ops->id, &file_ops->enable,
1302	1302	&file_ops->filter, &file_ops->format);
1303	1303	}
...	...	@@ -1367,8 +1367,8 @@
1367	1367	.priority = 0,
1368	1368	};
1369	1369
1370		-extern struct ftrace_event_call __start_ftrace_events[];
1371		-extern struct ftrace_event_call __stop_ftrace_events[];
	1370	+extern struct ftrace_event_call *__start_ftrace_events[];
	1371	+extern struct ftrace_event_call *__stop_ftrace_events[];
1372	1372
1373	1373	static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
1374	1374
...	...	@@ -1384,7 +1384,7 @@
1384	1384
1385	1385	static __init int event_trace_init(void)
1386	1386	{
1387		- struct ftrace_event_call *call;
	1387	+ struct ftrace_event_call **call;
1388	1388	struct dentry *d_tracer;
1389	1389	struct dentry *entry;
1390	1390	struct dentry *d_events;
...	...	@@ -1430,7 +1430,7 @@
1430	1430	pr_warning("tracing: Failed to allocate common fields");
1431	1431
1432	1432	for_each_event(call, __start_ftrace_events, __stop_ftrace_events) {
1433		- __trace_add_event_call(call, NULL, &ftrace_event_id_fops,
	1433	+ __trace_add_event_call(*call, NULL, &ftrace_event_id_fops,
1434	1434	&ftrace_enable_fops,
1435	1435	&ftrace_event_filter_fops,
1436	1436	&ftrace_event_format_fops);
...	...	@@ -161,14 +161,14 @@
161	161	.fields = LIST_HEAD_INIT(event_class_ftrace_##call.fields),\
162	162	}; \
163	163	\
164		-struct ftrace_event_call __used \
165		-__attribute__((__aligned__(4))) \
166		-__attribute__((section("_ftrace_events"))) event_##call = { \
	164	+struct ftrace_event_call __used event_##call = { \
167	165	.name = #call, \
168	166	.event.type = etype, \
169	167	.class = &event_class_ftrace_##call, \
170	168	.print_fmt = print, \
171	169	}; \
	170	+struct ftrace_event_call __used \
	171	+__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call;
172	172
173	173	#include "trace_entries.h"
...	...	@@ -55,20 +55,21 @@
55	55	.raw_init = init_syscall_trace,
56	56	};
57	57
58		-extern unsigned long __start_syscalls_metadata[];
59		-extern unsigned long __stop_syscalls_metadata[];
	58	+extern struct syscall_metadata *__start_syscalls_metadata[];
	59	+extern struct syscall_metadata *__stop_syscalls_metadata[];
60	60
61	61	static struct syscall_metadata **syscalls_metadata;
62	62
63		-static struct syscall_metadata *find_syscall_meta(unsigned long syscall)
	63	+static __init struct syscall_metadata *
	64	+find_syscall_meta(unsigned long syscall)
64	65	{
65		- struct syscall_metadata *start;
66		- struct syscall_metadata *stop;
	66	+ struct syscall_metadata **start;
	67	+ struct syscall_metadata **stop;
67	68	char str[KSYM_SYMBOL_LEN];
68	69
69	70
70		- start = (struct syscall_metadata *)__start_syscalls_metadata;
71		- stop = (struct syscall_metadata *)__stop_syscalls_metadata;
	71	+ start = __start_syscalls_metadata;
	72	+ stop = __stop_syscalls_metadata;
72	73	kallsyms_lookup(syscall, NULL, NULL, NULL, str);
73	74
74	75	for ( ; start < stop; start++) {
...	...	@@ -78,8 +79,8 @@
78	79	* with "SyS" instead of "sys", leading to an unwanted
79	80	* mismatch.
80	81	*/
81		- if (start->name && !strcmp(start->name + 3, str + 3))
82		- return start;
	82	+ if ((start)->name && !strcmp((start)->name + 3, str + 3))
	83	+ return *start;
83	84	}
84	85	return NULL;
85	86	}
...	...	@@ -27,8 +27,8 @@
27	27	#include <linux/sched.h>
28	28	#include <linux/jump_label.h>
29	29
30		-extern struct tracepoint __start___tracepoints[];
31		-extern struct tracepoint __stop___tracepoints[];
	30	+extern struct tracepoint * const __start___tracepoints_ptrs[];
	31	+extern struct tracepoint * const __stop___tracepoints_ptrs[];
32	32
33	33	/* Set to 1 to enable tracepoint debug output */
34	34	static const int tracepoint_debug;
35	35
...	...	@@ -298,10 +298,10 @@
298	298	*
299	299	* Updates the probe callback corresponding to a range of tracepoints.
300	300	*/
301		-void
302		-tracepoint_update_probe_range(struct tracepoint begin, struct tracepoint end)
	301	+void tracepoint_update_probe_range(struct tracepoint * const *begin,
	302	+ struct tracepoint * const *end)
303	303	{
304		- struct tracepoint *iter;
	304	+ struct tracepoint * const *iter;
305	305	struct tracepoint_entry *mark_entry;
306	306
307	307	if (!begin)
308	308
309	309
...	...	@@ -309,12 +309,12 @@
309	309
310	310	mutex_lock(&tracepoints_mutex);
311	311	for (iter = begin; iter < end; iter++) {
312		- mark_entry = get_tracepoint(iter->name);
	312	+ mark_entry = get_tracepoint((*iter)->name);
313	313	if (mark_entry) {
314		- set_tracepoint(&mark_entry, iter,
	314	+ set_tracepoint(&mark_entry, *iter,
315	315	!!mark_entry->refcount);
316	316	} else {
317		- disable_tracepoint(iter);
	317	+ disable_tracepoint(*iter);
318	318	}
319	319	}
320	320	mutex_unlock(&tracepoints_mutex);
...	...	@@ -326,8 +326,8 @@
326	326	static void tracepoint_update_probes(void)
327	327	{
328	328	/* Core kernel tracepoints */
329		- tracepoint_update_probe_range(__start___tracepoints,
330		- __stop___tracepoints);
	329	+ tracepoint_update_probe_range(__start___tracepoints_ptrs,
	330	+ __stop___tracepoints_ptrs);
331	331	/* tracepoints in modules. */
332	332	module_update_tracepoints();
333	333	}
...	...	@@ -514,8 +514,8 @@
514	514	* Will return the first tracepoint in the range if the input tracepoint is
515	515	* NULL.
516	516	*/
517		-int tracepoint_get_iter_range(struct tracepoint **tracepoint,
518		- struct tracepoint begin, struct tracepoint end)
	517	+int tracepoint_get_iter_range(struct tracepoint * const **tracepoint,
	518	+ struct tracepoint * const begin, struct tracepoint const *end)
519	519	{
520	520	if (!*tracepoint && begin != end) {
521	521	*tracepoint = begin;
...	...	@@ -534,7 +534,8 @@
534	534	/* Core kernel tracepoints */
535	535	if (!iter->module) {
536	536	found = tracepoint_get_iter_range(&iter->tracepoint,
537		- __start___tracepoints, __stop___tracepoints);
	537	+ __start___tracepoints_ptrs,
	538	+ __stop___tracepoints_ptrs);
538	539	if (found)
539	540	goto end;
540	541	}
...	...	@@ -585,8 +586,8 @@
585	586	switch (val) {
586	587	case MODULE_STATE_COMING:
587	588	case MODULE_STATE_GOING:
588		- tracepoint_update_probe_range(mod->tracepoints,
589		- mod->tracepoints + mod->num_tracepoints);
	589	+ tracepoint_update_probe_range(mod->tracepoints_ptrs,
	590	+ mod->tracepoints_ptrs + mod->num_tracepoints);
590	591	break;
591	592	}
592	593	return 0;