mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-25 05:04:09 +08:00
8751d15426
Every task_work will try to wake the task to be executed, which causes excessive scheduling and additional overhead. For some tw it's justified, but others won't do much but post a single CQE. When a task waits for multiple cqes, every such task_work will wake it up. Instead, the task may give a hint about how many cqes it waits for, io_req_local_work_add() will compare against it and skip wake ups if #cqes + #tw is not enough to satisfy the waiting condition. Task_work that uses the optimisation should be simple enough and never post more than one CQE. It's also ignored for non DEFER_TASKRUN rings. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/d2b77e99d1e86624d8a69f7037d764b739dcd225.1680782017.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
54 lines
1.2 KiB
C
54 lines
1.2 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
|
|
#include <linux/net.h>
|
|
#include <linux/uio.h>
|
|
#include <net/sock.h>
|
|
#include <linux/nospec.h>
|
|
|
|
#include "rsrc.h"
|
|
|
|
#define IO_NOTIF_SPLICE_BATCH 32
|
|
|
|
struct io_notif_data {
|
|
struct file *file;
|
|
struct ubuf_info uarg;
|
|
unsigned long account_pages;
|
|
bool zc_report;
|
|
bool zc_used;
|
|
bool zc_copied;
|
|
};
|
|
|
|
struct io_kiocb *io_alloc_notif(struct io_ring_ctx *ctx);
|
|
void io_notif_set_extended(struct io_kiocb *notif);
|
|
|
|
static inline struct io_notif_data *io_notif_to_data(struct io_kiocb *notif)
|
|
{
|
|
return io_kiocb_to_cmd(notif, struct io_notif_data);
|
|
}
|
|
|
|
static inline void io_notif_flush(struct io_kiocb *notif)
|
|
__must_hold(¬if->ctx->uring_lock)
|
|
{
|
|
struct io_notif_data *nd = io_notif_to_data(notif);
|
|
|
|
/* drop slot's master ref */
|
|
if (refcount_dec_and_test(&nd->uarg.refcnt))
|
|
__io_req_task_work_add(notif, IOU_F_TWQ_LAZY_WAKE);
|
|
}
|
|
|
|
static inline int io_notif_account_mem(struct io_kiocb *notif, unsigned len)
|
|
{
|
|
struct io_ring_ctx *ctx = notif->ctx;
|
|
struct io_notif_data *nd = io_notif_to_data(notif);
|
|
unsigned nr_pages = (len >> PAGE_SHIFT) + 2;
|
|
int ret;
|
|
|
|
if (ctx->user) {
|
|
ret = __io_account_mem(ctx->user, nr_pages);
|
|
if (ret)
|
|
return ret;
|
|
nd->account_pages += nr_pages;
|
|
}
|
|
return 0;
|
|
}
|