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-rw-r--r--include/asm-generic/vmlinux.lds.h8
-rw-r--r--include/linux/module.h2
-rw-r--r--include/linux/tracepoint.h35
-rw-r--r--kernel/module.c16
-rw-r--r--kernel/tracepoint.c31
5 files changed, 50 insertions, 42 deletions
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index f53708be95eb..57b1b6811b61 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -166,10 +166,8 @@
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) = .; \
@@ -218,6 +216,10 @@
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 */ \
} \
diff --git a/include/linux/module.h b/include/linux/module.h
index 7695a303bb55..9bdf27c7615b 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -377,7 +377,7 @@ struct module
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
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index c6814616653b..97c84a58efb8 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -33,12 +33,7 @@ struct tracepoint {
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 @@ extern void tracepoint_probe_update_all(void);
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 @@ static inline void tracepoint_synchronize_unregister(void)
#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 @@ do_trace: \
{ \
}
+/*
+ * 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);
diff --git a/kernel/module.c b/kernel/module.c
index 34e00b708fad..efa290ea94bf 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2460,9 +2460,9 @@ static void find_module_sections(struct module *mod, struct load_info *info)
#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 @@ void module_layout(struct module *mod,
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 @@ void module_update_tracepoints(void)
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 @@ int module_get_iter_tracepoints(struct tracepoint_iter *iter)
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;
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index e95ee7f31d43..68187af4889e 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -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 @@ static void disable_tracepoint(struct tracepoint *elem)
*
* 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 @@ tracepoint_update_probe_range(struct tracepoint *begin, struct tracepoint *end)
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 @@ tracepoint_update_probe_range(struct tracepoint *begin, struct tracepoint *end)
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 @@ EXPORT_SYMBOL_GPL(tracepoint_probe_update_all);
* 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 @@ static void tracepoint_get_iter(struct tracepoint_iter *iter)
/* 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 @@ int tracepoint_module_notify(struct notifier_block *self,
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;
generated by cgit v1.2.3 (git 2.0.4) at 2024-11-14 09:13:10 +0000