util/defer-call: move defer_call() to util/

The networking subsystem may wish to use defer_call(), so move the code
to util/ where it can be reused.

As a reminder of what defer_call() does:

This API defers a function call within a defer_call_begin()/defer_call_end()
section, allowing multiple calls to batch up. This is a performance
optimization that is used in the block layer to submit several I/O requests
at once instead of individually:

  defer_call_begin(); <-- start of section
  ...
  defer_call(my_func, my_obj); <-- deferred my_func(my_obj) call
  defer_call(my_func, my_obj); <-- another
  defer_call(my_func, my_obj); <-- another
  ...
  defer_call_end(); <-- end of section, my_func(my_obj) is called once

Suggested-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230913200045.1024233-3-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2023-09-13 16:00:43 -04:00 committed by Kevin Wolf
parent ccee48aa73
commit 433fcea40c
13 changed files with 27 additions and 7 deletions

View File

@ -2755,12 +2755,13 @@ S: Supported
F: util/async.c
F: util/aio-*.c
F: util/aio-*.h
F: util/defer-call.c
F: util/fdmon-*.c
F: block/io.c
F: block/plug.c
F: migration/block*
F: include/block/aio.h
F: include/block/aio-wait.h
F: include/qemu/defer-call.h
F: scripts/qemugdb/aio.py
F: tests/unit/test-fdmon-epoll.c
T: git https://github.com/stefanha/qemu.git block

View File

@ -13,6 +13,7 @@
#include "block/block_int.h"
#include "exec/memory.h"
#include "exec/cpu-common.h" /* for qemu_ram_get_fd() */
#include "qemu/defer-call.h"
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "qapi/qmp/qdict.h"

View File

@ -15,6 +15,7 @@
#include "block/block.h"
#include "block/raw-aio.h"
#include "qemu/coroutine.h"
#include "qemu/defer-call.h"
#include "qapi/error.h"
#include "sysemu/block-backend.h"
#include "trace.h"

View File

@ -14,6 +14,7 @@
#include "block/raw-aio.h"
#include "qemu/event_notifier.h"
#include "qemu/coroutine.h"
#include "qemu/defer-call.h"
#include "qapi/error.h"
#include "sysemu/block-backend.h"

View File

@ -21,7 +21,6 @@ block_ss.add(files(
'mirror.c',
'nbd.c',
'null.c',
'plug.c',
'preallocate.c',
'progress_meter.c',
'qapi.c',

View File

@ -16,6 +16,7 @@
#include "qapi/error.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qstring.h"
#include "qemu/defer-call.h"
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "qemu/module.h"

View File

@ -19,6 +19,7 @@
*/
#include "qemu/osdep.h"
#include "qemu/defer-call.h"
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "qemu/memalign.h"

View File

@ -12,6 +12,7 @@
*/
#include "qemu/osdep.h"
#include "qemu/defer-call.h"
#include "qapi/error.h"
#include "qemu/iov.h"
#include "qemu/module.h"

View File

@ -18,6 +18,7 @@
#include "standard-headers/linux/virtio_ids.h"
#include "hw/virtio/virtio-scsi.h"
#include "migration/qemu-file-types.h"
#include "qemu/defer-call.h"
#include "qemu/error-report.h"
#include "qemu/iov.h"
#include "qemu/module.h"

16
include/qemu/defer-call.h Normal file
View File

@ -0,0 +1,16 @@
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Deferred calls
*
* Copyright Red Hat.
*/
#ifndef QEMU_DEFER_CALL_H
#define QEMU_DEFER_CALL_H
/* See documentation in util/defer-call.c */
void defer_call_begin(void);
void defer_call_end(void);
void defer_call(void (*fn)(void *), void *opaque);
#endif /* QEMU_DEFER_CALL_H */

View File

@ -100,10 +100,6 @@ void blk_iostatus_set_err(BlockBackend *blk, int error);
int blk_get_max_iov(BlockBackend *blk);
int blk_get_max_hw_iov(BlockBackend *blk);
void defer_call_begin(void);
void defer_call_end(void);
void defer_call(void (*fn)(void *), void *opaque);
AioContext *blk_get_aio_context(BlockBackend *blk);
BlockAcctStats *blk_get_stats(BlockBackend *blk);
void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,

View File

@ -22,7 +22,7 @@
#include "qemu/coroutine-tls.h"
#include "qemu/notify.h"
#include "qemu/thread.h"
#include "sysemu/block-backend.h"
#include "qemu/defer-call.h"
/* A function call that has been deferred until defer_call_end() */
typedef struct {

View File

@ -28,6 +28,7 @@ util_ss.add(when: 'CONFIG_WIN32', if_true: pathcch)
if glib_has_gslice
util_ss.add(files('qtree.c'))
endif
util_ss.add(files('defer-call.c'))
util_ss.add(files('envlist.c', 'path.c', 'module.c'))
util_ss.add(files('host-utils.c'))
util_ss.add(files('bitmap.c', 'bitops.c'))