perf_counter: SIGIO support (3c446b3d) · Commits · 戴 / test

include/linux/perf_counter.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -238,6 +238,7 @@ enum perf_event_type {
		#include <linux/rcupdate.h>
		#include <linux/spinlock.h>
		#include <linux/hrtimer.h>
		#include <linux/fs.h>
		#include <asm/atomic.h>

		struct task_struct;
		@@ -398,6 +399,7 @@ struct perf_counter {

		/* poll related */
		wait_queue_head_t waitq;
		struct fasync_struct *fasync;
		/* optional: for NMIs */
		struct perf_wakeup_entry wakeup;

+19 −1

Original line number	Diff line number	Diff line
		@@ -1526,6 +1526,22 @@ out:
		return ret;
		}

		static int perf_fasync(int fd, struct file *filp, int on)
		{
		struct perf_counter *counter = filp->private_data;
		struct inode *inode = filp->f_path.dentry->d_inode;
		int retval;

		mutex_lock(&inode->i_mutex);
		retval = fasync_helper(fd, filp, on, &counter->fasync);
		mutex_unlock(&inode->i_mutex);

		if (retval < 0)
		return retval;

		return 0;
		}

		static const struct file_operations perf_fops = {
		.release = perf_release,
		.read = perf_read,
		@@ -1533,6 +1549,7 @@ static const struct file_operations perf_fops = {
		.unlocked_ioctl = perf_ioctl,
		.compat_ioctl = perf_ioctl,
		.mmap = perf_mmap,
		.fasync = perf_fasync,
		};

		/*
		@@ -1549,7 +1566,7 @@ void perf_counter_wakeup(struct perf_counter *counter)
		rcu_read_lock();
		data = rcu_dereference(counter->data);
		if (data) {
		(void)atomic_xchg(&data->wakeup, POLL_IN);
		atomic_set(&data->wakeup, POLL_IN);
		/*
		* Ensure all data writes are issued before updating the
		* user-space data head information. The matching rmb()
		@@ -1561,6 +1578,7 @@ void perf_counter_wakeup(struct perf_counter *counter)
		rcu_read_unlock();

		wake_up_all(&counter->waitq);
		kill_fasync(&counter->fasync, SIGIO, POLL_IN);
		}

		/*