2149675b19
The newly added function v9fs_co_readdir_many() retrieves multiple directory entries with a single fs driver request. It is intended to replace uses of v9fs_co_readdir(), the latter only retrieves a single directory entry per fs driver request instead. The reason for this planned replacement is that for every fs driver request the coroutine is dispatched from main I/O thread to a background I/O thread and eventually dispatched back to main I/O thread. Hopping between threads adds latency. So if a 9pfs Treaddir request reads a large amount of directory entries, this currently sums up to huge latencies of several hundred ms or even more. So using v9fs_co_readdir_many() instead of v9fs_co_readdir() will provide significant performance improvements. Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com> Message-Id: <73dc827a12ef577ae7e644dcf34a5c0e443ab42f.1596012787.git.qemu_oss@crudebyte.com> Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
102 lines
5.1 KiB
C
102 lines
5.1 KiB
C
/*
|
|
* 9p backend
|
|
*
|
|
* Copyright IBM, Corp. 2010
|
|
*
|
|
* Authors:
|
|
* Harsh Prateek Bora <harsh@linux.vnet.ibm.com>
|
|
* Venkateswararao Jujjuri(JV) <jvrao@linux.vnet.ibm.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2. See
|
|
* the COPYING file in the top-level directory.
|
|
*
|
|
*/
|
|
|
|
#ifndef QEMU_9P_COTH_H
|
|
#define QEMU_9P_COTH_H
|
|
|
|
#include "qemu/thread.h"
|
|
#include "qemu/coroutine.h"
|
|
#include "9p.h"
|
|
|
|
/*
|
|
* we want to use bottom half because we want to make sure the below
|
|
* sequence of events.
|
|
*
|
|
* 1. Yield the coroutine in the QEMU thread.
|
|
* 2. Submit the coroutine to a worker thread.
|
|
* 3. Enter the coroutine in the worker thread.
|
|
* we cannot swap step 1 and 2, because that would imply worker thread
|
|
* can enter coroutine while step1 is still running
|
|
*/
|
|
#define v9fs_co_run_in_worker(code_block) \
|
|
do { \
|
|
QEMUBH *co_bh; \
|
|
co_bh = qemu_bh_new(co_run_in_worker_bh, \
|
|
qemu_coroutine_self()); \
|
|
qemu_bh_schedule(co_bh); \
|
|
/* \
|
|
* yield in qemu thread and re-enter back \
|
|
* in worker thread \
|
|
*/ \
|
|
qemu_coroutine_yield(); \
|
|
qemu_bh_delete(co_bh); \
|
|
code_block; \
|
|
/* re-enter back to qemu thread */ \
|
|
qemu_coroutine_yield(); \
|
|
} while (0)
|
|
|
|
void co_run_in_worker_bh(void *);
|
|
int coroutine_fn v9fs_co_readlink(V9fsPDU *, V9fsPath *, V9fsString *);
|
|
int coroutine_fn v9fs_co_readdir(V9fsPDU *, V9fsFidState *, struct dirent **);
|
|
int coroutine_fn v9fs_co_readdir_many(V9fsPDU *, V9fsFidState *,
|
|
struct V9fsDirEnt **, off_t, int32_t,
|
|
bool);
|
|
off_t coroutine_fn v9fs_co_telldir(V9fsPDU *, V9fsFidState *);
|
|
void coroutine_fn v9fs_co_seekdir(V9fsPDU *, V9fsFidState *, off_t);
|
|
void coroutine_fn v9fs_co_rewinddir(V9fsPDU *, V9fsFidState *);
|
|
int coroutine_fn v9fs_co_statfs(V9fsPDU *, V9fsPath *, struct statfs *);
|
|
int coroutine_fn v9fs_co_lstat(V9fsPDU *, V9fsPath *, struct stat *);
|
|
int coroutine_fn v9fs_co_chmod(V9fsPDU *, V9fsPath *, mode_t);
|
|
int coroutine_fn v9fs_co_utimensat(V9fsPDU *, V9fsPath *, struct timespec [2]);
|
|
int coroutine_fn v9fs_co_chown(V9fsPDU *, V9fsPath *, uid_t, gid_t);
|
|
int coroutine_fn v9fs_co_truncate(V9fsPDU *, V9fsPath *, off_t);
|
|
int coroutine_fn v9fs_co_llistxattr(V9fsPDU *, V9fsPath *, void *, size_t);
|
|
int coroutine_fn v9fs_co_lgetxattr(V9fsPDU *, V9fsPath *,
|
|
V9fsString *, void *, size_t);
|
|
int coroutine_fn v9fs_co_mknod(V9fsPDU *, V9fsFidState *, V9fsString *, uid_t,
|
|
gid_t, dev_t, mode_t, struct stat *);
|
|
int coroutine_fn v9fs_co_mkdir(V9fsPDU *, V9fsFidState *, V9fsString *,
|
|
mode_t, uid_t, gid_t, struct stat *);
|
|
int coroutine_fn v9fs_co_remove(V9fsPDU *, V9fsPath *);
|
|
int coroutine_fn v9fs_co_rename(V9fsPDU *, V9fsPath *, V9fsPath *);
|
|
int coroutine_fn v9fs_co_unlinkat(V9fsPDU *, V9fsPath *, V9fsString *,
|
|
int flags);
|
|
int coroutine_fn v9fs_co_renameat(V9fsPDU *, V9fsPath *, V9fsString *,
|
|
V9fsPath *, V9fsString *);
|
|
int coroutine_fn v9fs_co_fstat(V9fsPDU *, V9fsFidState *, struct stat *);
|
|
int coroutine_fn v9fs_co_opendir(V9fsPDU *, V9fsFidState *);
|
|
int coroutine_fn v9fs_co_open(V9fsPDU *, V9fsFidState *, int);
|
|
int coroutine_fn v9fs_co_open2(V9fsPDU *, V9fsFidState *, V9fsString *,
|
|
gid_t, int, int, struct stat *);
|
|
int coroutine_fn v9fs_co_lsetxattr(V9fsPDU *, V9fsPath *, V9fsString *,
|
|
void *, size_t, int);
|
|
int coroutine_fn v9fs_co_lremovexattr(V9fsPDU *, V9fsPath *, V9fsString *);
|
|
int coroutine_fn v9fs_co_closedir(V9fsPDU *, V9fsFidOpenState *);
|
|
int coroutine_fn v9fs_co_close(V9fsPDU *, V9fsFidOpenState *);
|
|
int coroutine_fn v9fs_co_fsync(V9fsPDU *, V9fsFidState *, int);
|
|
int coroutine_fn v9fs_co_symlink(V9fsPDU *, V9fsFidState *, V9fsString *,
|
|
const char *, gid_t, struct stat *);
|
|
int coroutine_fn v9fs_co_link(V9fsPDU *, V9fsFidState *,
|
|
V9fsFidState *, V9fsString *);
|
|
int coroutine_fn v9fs_co_pwritev(V9fsPDU *, V9fsFidState *,
|
|
struct iovec *, int, int64_t);
|
|
int coroutine_fn v9fs_co_preadv(V9fsPDU *, V9fsFidState *,
|
|
struct iovec *, int, int64_t);
|
|
int coroutine_fn v9fs_co_name_to_path(V9fsPDU *, V9fsPath *,
|
|
const char *, V9fsPath *);
|
|
int coroutine_fn v9fs_co_st_gen(V9fsPDU *pdu, V9fsPath *path, mode_t,
|
|
V9fsStatDotl *v9stat);
|
|
|
|
#endif
|