From: Xiaoguang Wang <[email protected]>
To: [email protected]
Cc: [email protected], [email protected]
Subject: [PATCH v2] io_uring: defer alloc_hint update to io_file_bitmap_set()
Date: Sat, 28 May 2022 01:39:14 +0800 [thread overview]
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
io_file_bitmap_get() returns a free bitmap slot, but if it isn't
used later, such as io_queue_rsrc_removal() returns error, in this
case, we should not update alloc_hint at all, which still should
be considered as a valid candidate for next io_file_bitmap_get()
calls.
To fix this issue, only update alloc_hint in io_file_bitmap_set().
Signed-off-by: Xiaoguang Wang <[email protected]>
---
V2:
Delete unnecessary check against to alloc_hint.
---
fs/io_uring.c | 21 +++++++++------------
1 file changed, 9 insertions(+), 12 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index ff50e5f1753d..212d6ae88114 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -5419,15 +5419,11 @@ static int io_file_bitmap_get(struct io_ring_ctx *ctx)
unsigned long nr = ctx->nr_user_files;
int ret;
- if (table->alloc_hint >= nr)
- table->alloc_hint = 0;
-
do {
ret = find_next_zero_bit(table->bitmap, nr, table->alloc_hint);
- if (ret != nr) {
- table->alloc_hint = ret + 1;
+ if (ret != nr)
return ret;
- }
+
if (!table->alloc_hint)
break;
@@ -9650,12 +9646,13 @@ static void io_free_file_tables(struct io_file_table *table)
table->bitmap = NULL;
}
-static inline void io_file_bitmap_set(struct io_file_table *table, int bit)
+static inline void io_file_bitmap_set(struct io_ring_ctx *ctx, int bit)
{
+ struct io_file_table *table = &ctx->file_table;
+
WARN_ON_ONCE(test_bit(bit, table->bitmap));
__set_bit(bit, table->bitmap);
- if (bit == table->alloc_hint)
- table->alloc_hint++;
+ table->alloc_hint = bit + 1;
}
static inline void io_file_bitmap_clear(struct io_file_table *table, int bit)
@@ -10080,7 +10077,7 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
}
file_slot = io_fixed_file_slot(&ctx->file_table, i);
io_fixed_file_set(file_slot, file);
- io_file_bitmap_set(&ctx->file_table, i);
+ io_file_bitmap_set(ctx, i);
}
io_rsrc_node_switch(ctx, NULL);
@@ -10161,7 +10158,7 @@ static int io_install_fixed_file(struct io_kiocb *req, unsigned int issue_flags,
if (!ret) {
*io_get_tag_slot(ctx->file_data, slot_index) = 0;
io_fixed_file_set(file_slot, file);
- io_file_bitmap_set(&ctx->file_table, slot_index);
+ io_file_bitmap_set(ctx, slot_index);
}
err:
if (needs_switch)
@@ -10284,7 +10281,7 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx,
}
*io_get_tag_slot(data, i) = tag;
io_fixed_file_set(file_slot, file);
- io_file_bitmap_set(&ctx->file_table, i);
+ io_file_bitmap_set(ctx, i);
}
}
--
2.14.4.44.g2045bb6
next prev parent reply other threads:[~2022-05-27 17:39 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-27 16:53 [PATCH 0/2] two bug fixes about direct fd install Xiaoguang Wang
2022-05-27 16:53 ` [PATCH 1/2] io_uring: fix file leaks around io_fixed_fd_install() Xiaoguang Wang
2022-05-27 17:00 ` Jens Axboe
2022-05-27 16:53 ` [PATCH 2/2] io_uring: defer alloc_hint update to io_file_bitmap_set() Xiaoguang Wang
2022-05-27 17:09 ` Jens Axboe
2022-05-27 17:39 ` Xiaoguang Wang [this message]
2022-05-27 18:03 ` [PATCH v2] " Jens Axboe
2022-05-28 1:45 ` Xiaoguang Wang
2022-05-28 1:51 ` [PATCH v3] " Xiaoguang Wang
2022-05-28 2:14 ` Jens Axboe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220527173914.50320-1-xiaoguang.wang@linux.alibaba.com \
[email protected] \
[email protected] \
[email protected] \
[email protected] \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox