[PATCH 4/6] perf_counter: Add PERF_COUNTER_IOC_SET_FILTER ioctl

Li Zefan
2009-09-07T08:14:53Z

Allow to set profile filter via ioctl.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
---
include/linux/perf_counter.h | 1 +
kernel/perf_counter.c | 40 +++++++++++++++++++++++++++++++++++++---
2 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index 972f90d..7a750b3 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -217,6 +217,7 @@ struct perf_counter_attr {
#define PERF_COUNTER_IOC_RESET _IO ('$', 3)
#define PERF_COUNTER_IOC_PERIOD _IOW('$', 4, u64)
#define PERF_COUNTER_IOC_SET_OUTPUT _IO ('$', 5)
+#define PERF_COUNTER_IOC_SET_FILTER _IOW('$', 6, char *)

enum perf_counter_ioc_flags {
PERF_IOC_FLAG_GROUP = 1U << 0,
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index e0d91fd..3fd65e8 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -1988,7 +1988,9 @@ unlock:
return ret;
}

-int perf_counter_set_output(struct perf_counter *counter, int output_fd);
+static int perf_counter_set_output(struct perf_counter *counter, int output_fd);
+static int perf_counter_set_filter(struct perf_counter *counter,
+ void __user *arg);

static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
@@ -2016,6 +2018,9 @@ static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case PERF_COUNTER_IOC_SET_OUTPUT:
return perf_counter_set_output(counter, arg);

+ case PERF_COUNTER_IOC_SET_FILTER:
+ return perf_counter_set_filter(counter, (void __user *)arg);
+
default:
return -ENOTTY;
}
@@ -3964,6 +3969,7 @@ EXPORT_SYMBOL_GPL(perf_tpcounter_event);

extern int ftrace_profile_enable(int);
extern void ftrace_profile_disable(int);
+extern int ftrace_profile_set_filter(int, char *);

static void tp_perf_counter_destroy(struct perf_counter *counter)
{
@@ -3988,12 +3994,40 @@ static const struct pmu *tp_perf_counter_init(struct perf_counter *counter)

return &perf_ops_generic;
}
+
+static int perf_counter_set_filter(struct perf_counter *counter,
+ void __user *arg)
+{
+ char *filter_str;
+ int ret;
+
+ if (counter->attr.type != PERF_TYPE_TRACEPOINT)
+ return -EINVAL;
+
+ filter_str = strndup_user(arg, PAGE_SIZE);
+ if (IS_ERR(filter_str))
+ return PTR_ERR(filter_str);
+
+ ret = ftrace_profile_set_filter(counter->attr.config, filter_str);
+
+ kfree(filter_str);
+ return ret;
+}
+
#else
+
static const struct pmu *tp_perf_counter_init(struct perf_counter *counter)
{
return NULL;
}
-#endif
+
+static int perf_counter_set_filter(struct perf_counter *counter,
+ void __user *arg)
+{
+ return -EINVAL;
+}
+
+#endif /* CONFIG_EVENT_PROFILE */

atomic_t perf_swcounter_enabled[PERF_COUNT_SW_MAX];

@@ -4246,7 +4280,7 @@ err_size:
goto out;
}

-int perf_counter_set_output(struct perf_counter *counter, int output_fd)
+static int perf_counter_set_output(struct perf_counter *counter, int output_fd)
{
struct perf_counter *output_counter = NULL;
struct file *output_file = NULL;
--
1.6.3