[PATCH 6/8] percpu: add __percpu sparse annotations to trace

Tejun Heo
2010-01-25T15:20:18Z

Add __percpu sparse annotations to trace.

These annotations are to make sparse consider percpu variables to be
in a different address space and warn if accessed without going
through percpu accessors. This patch doesn't affect normal builds.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
---
include/linux/ftrace_event.h | 4 ++--
include/trace/ftrace.h | 4 ++--
kernel/trace/trace_event_profile.c | 16 ++++++++--------
kernel/trace/trace_functions_graph.c | 2 +-
kernel/trace/trace_kprobe.c | 4 ++--
kernel/trace/trace_ksym.c | 10 +++++-----
kernel/trace/trace_syscalls.c | 4 ++--
7 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 2233c98..72fccdd 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -138,8 +138,8 @@ struct ftrace_event_call {

#define FTRACE_MAX_PROFILE_SIZE 2048

-extern char *perf_trace_buf;
-extern char *perf_trace_buf_nmi;
+extern char __percpu *perf_trace_buf;
+extern char __percpu *perf_trace_buf_nmi;

#define MAX_FILTER_PRED 32
#define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index c6fe03e..210d421 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -773,7 +773,7 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
* struct ftrace_event_call *event_call = &event_<call>;
* extern void perf_tp_event(int, u64, u64, void *, int);
* struct ftrace_raw_##call *entry;
- * struct perf_trace_buf *trace_buf;
+ * struct perf_trace_buf __percpu *trace_buf;
* u64 __addr = 0, __count = 1;
* unsigned long irq_flags;
* struct trace_entry *ent;
@@ -859,7 +859,7 @@ ftrace_profile_templ_##call(struct ftrace_event_call *event_call, \
struct trace_entry *ent; \
int __entry_size; \
int __data_size; \
- char *trace_buf; \
+ char __percpu *trace_buf; \
char *raw_data; \
int __cpu; \
int rctx; \
diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c
index 9e25573..4b16312 100644
--- a/kernel/trace/trace_event_profile.c
+++ b/kernel/trace/trace_event_profile.c
@@ -9,11 +9,11 @@
#include "trace.h"

-char *perf_trace_buf;
-EXPORT_SYMBOL_GPL(perf_trace_buf);
+char __percpu *perf_trace_buf;
+EXPORT_PER_CPU_SYMBOL_GPL(perf_trace_buf);

-char *perf_trace_buf_nmi;
-EXPORT_SYMBOL_GPL(perf_trace_buf_nmi);
+char __percpu *perf_trace_buf_nmi;
+EXPORT_PER_CPU_SYMBOL_GPL(perf_trace_buf_nmi);

typedef typeof(char [FTRACE_MAX_PROFILE_SIZE]) perf_trace_t ;

@@ -22,20 +22,20 @@ static int total_profile_count;

static int ftrace_profile_enable_event(struct ftrace_event_call *event)
{
- char *buf;
+ char __percpu *buf;
int ret = -ENOMEM;

if (event->profile_count++ > 0)
return 0;

if (!total_profile_count) {
- buf = (char *)alloc_percpu(perf_trace_t);
+ buf = (char __percpu *)alloc_percpu(perf_trace_t);
if (!buf)
goto fail_buf;

rcu_assign_pointer(perf_trace_buf, buf);

- buf = (char *)alloc_percpu(perf_trace_t);
+ buf = (char __percpu *)alloc_percpu(perf_trace_t);
if (!buf)
goto fail_buf_nmi;

@@ -81,7 +81,7 @@ int ftrace_profile_enable(int event_id)

static void ftrace_profile_disable_event(struct ftrace_event_call *event)
{
- char *buf, *nmi_buf;
+ char __percpu *buf, *nmi_buf;

if (--event->profile_count > 0)
return;
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 9d976f3..2144178 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -21,7 +21,7 @@ struct fgraph_cpu_data {
};

struct fgraph_data {
- struct fgraph_cpu_data *cpu_data;
+ struct fgraph_cpu_data __percpu *cpu_data;

/* Place to preserve last processed entry. */
struct ftrace_graph_ent_entry ent;
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 6ea90c0..4567950 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1262,7 +1262,7 @@ static __kprobes int kprobe_profile_func(struct kprobe *kp,
struct trace_entry *ent;
int size, __size, i, pc, __cpu;
unsigned long irq_flags;
- char *trace_buf;
+ char __percpu *trace_buf;
char *raw_data;
int rctx;

@@ -1327,7 +1327,7 @@ static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri,
struct trace_entry *ent;
int size, __size, i, pc, __cpu;
unsigned long irq_flags;
- char *trace_buf;
+ char __percpu *trace_buf;
char *raw_data;
int rctx;

diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c
index 94103cd..7e5c483 100644
--- a/kernel/trace/trace_ksym.c
+++ b/kernel/trace/trace_ksym.c
@@ -42,7 +42,7 @@
#define KSYM_TRACER_OP_LEN 3 /* rw- */

struct trace_ksym {
- struct perf_event **ksym_hbp;
+ struct perf_event * __percpu *ksym_hbp;
struct perf_event_attr attr;
#ifdef CONFIG_PROFILE_KSYM_TRACER
atomic64_t counter;
@@ -200,8 +200,8 @@ int process_new_ksym_entry(char *ksymname, int op, unsigned long addr)
entry->ksym_hbp = register_wide_hw_breakpoint(&entry->attr,
ksym_hbp_handler);

- if (IS_ERR(entry->ksym_hbp)) {
- ret = PTR_ERR(entry->ksym_hbp);
+ if (IS_ERR((void __force *)entry->ksym_hbp)) {
+ ret = PTR_ERR((void __force *)entry->ksym_hbp);
printk(KERN_INFO "ksym_tracer request failed. Try again"
" later!!\n");
goto err;
@@ -331,8 +331,8 @@ static ssize_t ksym_trace_filter_write(struct file *file,
entry->ksym_hbp =
register_wide_hw_breakpoint(&entry->attr,
ksym_hbp_handler);
- if (IS_ERR(entry->ksym_hbp))
- ret = PTR_ERR(entry->ksym_hbp);
+ if (IS_ERR((void __force *)entry->ksym_hbp))
+ ret = PTR_ERR((void __force *)entry->ksym_hbp);
else
goto out_unlock;
}
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 75289f3..9f7de51 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -433,7 +433,7 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
struct syscall_metadata *sys_data;
struct syscall_trace_enter *rec;
unsigned long flags;
- char *trace_buf;
+ char __percpu *trace_buf;
char *raw_data;
int syscall_nr;
int rctx;
@@ -531,7 +531,7 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
struct syscall_trace_exit *rec;
unsigned long flags;
int syscall_nr;
- char *trace_buf;
+ char __percpu *trace_buf;
char *raw_data;
int rctx;
int size;
--
1.6.4.2