summaryrefslogtreecommitdiffstats
path: root/qemu/tests/qapi-schema/enum-clash-member.err
diff options
context:
space:
mode:
authorYunhong Jiang <yunhong.jiang@gmail.com>2016-06-13 14:20:01 -0700
committerYunhong Jiang <yunhong.jiang@linux.intel.com>2016-07-18 08:06:50 -0700
commitebcdab040619575a47ad19b18e7ed5c38d287336 (patch)
treed806a3a9443fcf29245e37aa0efc5f4a4de5230c /qemu/tests/qapi-schema/enum-clash-member.err
parentab9c81f473b3feff08f1e51428fbaf6a93d4896a (diff)
KVM: x86: support using the vmx preemption timer for tsc deadline timer
The VMX preemption timer can be used to virtualize the TSC deadline timer. The VMX preemption timer is armed when the vCPU is running, and a VMExit will happen if the virtual TSC deadline timer expires. When the vCPU thread is blocked because of HLT, KVM will switch to use an hrtimer, and then go back to the VMX preemption timer when the vCPU thread is unblocked. This solution avoids the complex OS's hrtimer system, and the host timer interrupt handling cost, replacing them with a little math (for guest->host TSC and host TSC->preemption timer conversion) and a cheaper VMexit. This benefits latency for isolated pCPUs. [A word about performance... Yunhong reported a 30% reduction in average latency from cyclictest. I made a similar test with tscdeadline_latency from kvm-unit-tests, and measured - ~20 clock cycles loss (out of ~3200, so less than 1% but still statistically significant) in the worst case where the test halts just after programming the TSC deadline timer - ~800 clock cycles gain (25% reduction in latency) in the best case where the test busy waits. I removed the VMX bits from Yunhong's patch, to concentrate them in the next patch - Paolo] Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Change-Id: I4aa1ecfa3463d1cbfb317511b45d2074b33d9b6f upstream-status: backport Signed-off-by: Yunhong Jiang <yunhong.jiang@linux.intel.com>
Diffstat (limited to 'qemu/tests/qapi-schema/enum-clash-member.err')
0 files changed, 0 insertions, 0 deletions
id='n202' href='#n202'>202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261
/*
 * linux/fs/9p/vfs_dir.c
 *
 * This file contains vfs directory ops for the 9P2000 protocol.
 *
 *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
 *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  as published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to:
 *  Free Software Foundation
 *  51 Franklin Street, Fifth Floor
 *  Boston, MA  02111-1301  USA
 *
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/sched.h>
#include <linux/inet.h>
#include <linux/idr.h>
#include <linux/slab.h>
#include <linux/uio.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>

#include "v9fs.h"
#include "v9fs_vfs.h"
#include "fid.h"

/**
 * struct p9_rdir - readdir accounting
 * @head: start offset of current dirread buffer
 * @tail: end offset of current dirread buffer
 * @buf: dirread buffer
 *
 * private structure for keeping track of readdir
 * allocated on demand
 */

struct p9_rdir {
	int head;
	int tail;
	uint8_t buf[];
};

/**
 * dt_type - return file type
 * @mistat: mistat structure
 *
 */

static inline int dt_type(struct p9_wstat *mistat)
{
	unsigned long perm = mistat->mode;
	int rettype = DT_REG;

	if (perm & P9_DMDIR)
		rettype = DT_DIR;
	if (perm & P9_DMSYMLINK)
		rettype = DT_LNK;

	return rettype;
}

static void p9stat_init(struct p9_wstat *stbuf)
{
	stbuf->name  = NULL;
	stbuf->uid   = NULL;
	stbuf->gid   = NULL;
	stbuf->muid  = NULL;
	stbuf->extension = NULL;
}

/**
 * v9fs_alloc_rdir_buf - Allocate buffer used for read and readdir
 * @filp: opened file structure
 * @buflen: Length in bytes of buffer to allocate
 *
 */

static struct p9_rdir *v9fs_alloc_rdir_buf(struct file *filp, int buflen)
{
	struct p9_fid *fid = filp->private_data;
	if (!fid->rdir)
		fid->rdir = kzalloc(sizeof(struct p9_rdir) + buflen, GFP_KERNEL);
	return fid->rdir;
}

/**
 * v9fs_dir_readdir - iterate through a directory
 * @file: opened file structure
 * @ctx: actor we feed the entries to
 *
 */

static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
{
	bool over;
	struct p9_wstat st;
	int err = 0;
	struct p9_fid *fid;
	int buflen;
	int reclen = 0;
	struct p9_rdir *rdir;
	struct kvec kvec;

	p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
	fid = file->private_data;

	buflen = fid->clnt->msize - P9_IOHDRSZ;

	rdir = v9fs_alloc_rdir_buf(file, buflen);
	if (!rdir)
		return -ENOMEM;
	kvec.iov_base = rdir->buf;
	kvec.iov_len = buflen;

	while (1) {
		if (rdir->tail == rdir->head) {
			struct iov_iter to;
			int n;
			iov_iter_kvec(&to, READ | ITER_KVEC, &kvec, 1, buflen);
			n = p9_client_read(file->private_data, ctx->pos, &to,
					   &err);
			if (err)
				return err;
			if (n == 0)
				return 0;

			rdir->head = 0;
			rdir->tail = n;
		}
		while (rdir->head < rdir->tail) {
			p9stat_init(&st);
			err = p9stat_read(fid->clnt, rdir->buf + rdir->head,
					  rdir->tail - rdir->head, &st);
			if (err) {
				p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
				p9stat_free(&st);
				return -EIO;
			}
			reclen = st.size+2;

			over = !dir_emit(ctx, st.name, strlen(st.name),
					 v9fs_qid2ino(&st.qid), dt_type(&st));
			p9stat_free(&st);
			if (over)
				return 0;

			rdir->head += reclen;
			ctx->pos += reclen;
		}
	}
}

/**
 * v9fs_dir_readdir_dotl - iterate through a directory
 * @file: opened file structure
 * @ctx: actor we feed the entries to
 *
 */
static int v9fs_dir_readdir_dotl(struct file *file, struct dir_context *ctx)
{
	int err = 0;
	struct p9_fid *fid;
	int buflen;
	struct p9_rdir *rdir;
	struct p9_dirent curdirent;

	p9_debug(P9_DEBUG_VFS, "name %pD\n", file);
	fid = file->private_data;

	buflen = fid->clnt->msize - P9_READDIRHDRSZ;

	rdir = v9fs_alloc_rdir_buf(file, buflen);
	if (!rdir)
		return -ENOMEM;

	while (1) {
		if (rdir->tail == rdir->head) {
			err = p9_client_readdir(fid, rdir->buf, buflen,
						ctx->pos);
			if (err <= 0)
				return err;

			rdir->head = 0;
			rdir->tail = err;
		}

		while (rdir->head < rdir->tail) {

			err = p9dirent_read(fid->clnt, rdir->buf + rdir->head,
					    rdir->tail - rdir->head,
					    &curdirent);
			if (err < 0) {
				p9_debug(P9_DEBUG_VFS, "returned %d\n", err);
				return -EIO;
			}

			if (!dir_emit(ctx, curdirent.d_name,
				      strlen(curdirent.d_name),
				      v9fs_qid2ino(&curdirent.qid),
				      curdirent.d_type))
				return 0;

			ctx->pos = curdirent.d_off;
			rdir->head += err;
		}
	}
}


/**
 * v9fs_dir_release - close a directory
 * @inode: inode of the directory
 * @filp: file pointer to a directory
 *
 */

int v9fs_dir_release(struct inode *inode, struct file *filp)
{
	struct p9_fid *fid;

	fid = filp->private_data;
	p9_debug(P9_DEBUG_VFS, "inode: %p filp: %p fid: %d\n",
		 inode, filp, fid ? fid->fid : -1);
	if (fid)
		p9_client_clunk(fid);
	return 0;
}

const struct file_operations v9fs_dir_operations = {
	.read = generic_read_dir,
	.llseek = generic_file_llseek,
	.iterate = v9fs_dir_readdir,
	.open = v9fs_file_open,
	.release = v9fs_dir_release,
};

const struct file_operations v9fs_dir_operations_dotl = {
	.read = generic_read_dir,
	.llseek = generic_file_llseek,
	.iterate = v9fs_dir_readdir_dotl,
	.open = v9fs_file_open,
	.release = v9fs_dir_release,
        .fsync = v9fs_file_fsync_dotl,
};