/*
 * Implement the manual drop-all-pagecache function
 */

#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/writeback.h>
#include <linux/sysctl.h>
#include <linux/gfp.h>
#include "internal.h"

/* A global variable is a bit ugly, but it keeps the code simple */
int sysctl_drop_caches;

static void drop_pagecache_sb(struct super_block *sb, void *unused)
{
	struct inode *inode, *toput_inode = NULL;

	spin_lock(&sb->s_inode_list_lock);
	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
		spin_lock(&inode->i_lock);
		if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
		    (inode->i_mapping->nrpages == 0)) {
			spin_unlock(&inode->i_lock);
			continue;
		}
		__iget(inode);
		spin_unlock(&inode->i_lock);
		spin_unlock(&sb->s_inode_list_lock);

		invalidate_mapping_pages(inode->i_mapping, 0, -1);
		iput(toput_inode);
		toput_inode = inode;

		spin_lock(&sb->s_inode_list_lock);
	}
	spin_unlock(&sb->s_inode_list_lock);
	iput(toput_inode);
}

int drop_caches_sysctl_handler(struct ctl_table *table, int write,
	void __user *buffer, size_t *length, loff_t *ppos)
{
	int ret;

	ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
	if (ret)
		return ret;
	if (write) {
		static int stfu;

		if (sysctl_drop_caches & 1) {
			iterate_supers(drop_pagecache_sb, NULL);
			count_vm_event(DROP_PAGECACHE);
		}
		if (sysctl_drop_caches & 2) {
			drop_slab();
			count_vm_event(DROP_SLAB);
		}
		if (!stfu) {
			pr_info("%s (%d): drop_caches: %d\n",
				current->comm, task_pid_nr(current),
				sysctl_drop_caches);
		}
		stfu |= sysctl_drop_caches & 4;
	}
	return 0;
}
cd23dfc752'>refs</a><a href='/cgit.cgi/linux/net-next.git/log/sound/soc/intel/haswell'>log</a><a href='/cgit.cgi/linux/net-next.git/tree/sound/soc/intel/haswell?id=dfef358bd1beb4e7b5c94eca944be9cd23dfc752'>tree</a><a href='/cgit.cgi/linux/net-next.git/commit/sound/soc/intel/haswell?id=dfef358bd1beb4e7b5c94eca944be9cd23dfc752'>commit</a><a class='active' href='/cgit.cgi/linux/net-next.git/diff/sound/soc/intel/haswell?id=dfef358bd1beb4e7b5c94eca944be9cd23dfc752'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/sound/soc/intel/haswell'>
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<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/diff/?id=dfef358bd1beb4e7b5c94eca944be9cd23dfc752'>root</a>/<a href='/cgit.cgi/linux/net-next.git/diff/sound?id=dfef358bd1beb4e7b5c94eca944be9cd23dfc752'>sound</a>/<a href='/cgit.cgi/linux/net-next.git/diff/sound/soc?id=dfef358bd1beb4e7b5c94eca944be9cd23dfc752'>soc</a>/<a href='/cgit.cgi/linux/net-next.git/diff/sound/soc/intel?id=dfef358bd1beb4e7b5c94eca944be9cd23dfc752'>intel</a>/<a href='/cgit.cgi/linux/net-next.git/diff/sound/soc/intel/haswell?id=dfef358bd1beb4e7b5c94eca944be9cd23dfc752'>haswell</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='dfef358bd1beb4e7b5c94eca944be9cd23dfc752'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=dfef358bd1beb4e7b5c94eca944be9cd23dfc752'>Diffstat</a> (limited to 'sound/soc/intel/haswell')</div><table summary='diffstat' class='diffstat'>