[PATCH] io_uring: fix warnings on shadow variables

[PATCH] io_uring: fix warnings on shadow variables

[Jens Axboe]

There are a few of those:

io_uring/fdinfo.c:170:16: warning: declaration shadows a local variable [-Wshadow]
  170 |                 struct file *f = io_file_from_index(&ctx->file_table, i);
      |                              ^
io_uring/fdinfo.c:53:67: note: previous declaration is here
   53 | __cold void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
      |                                                                   ^
io_uring/cancel.c:187:25: warning: declaration shadows a local variable [-Wshadow]
  187 |                 struct io_uring_task *tctx = node->task->io_uring;
      |                                       ^
io_uring/cancel.c:166:31: note: previous declaration is here
  166 |                              struct io_uring_task *tctx,
      |                                                    ^
io_uring/register.c:371:25: warning: declaration shadows a local variable [-Wshadow]
  371 |                 struct io_uring_task *tctx = node->task->io_uring;
      |                                       ^
io_uring/register.c:312:24: note: previous declaration is here
  312 |         struct io_uring_task *tctx = NULL;
      |                               ^

and a simple cleanup gets rid of them. For the fdinfo case, make a
distinction between the file being passed in (for the ring), and the
registered files we iterate. For the other two cases, just get rid of
shadowed variable, there's no reason to have a new one.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 io_uring/cancel.c   | 4 +---
 io_uring/fdinfo.c   | 4 ++--
 io_uring/register.c | 3 +--
 3 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/io_uring/cancel.c b/io_uring/cancel.c
index acfcdd7f059a..a6e58a20efdd 100644
--- a/io_uring/cancel.c
+++ b/io_uring/cancel.c
@@ -184,9 +184,7 @@ static int __io_async_cancel(struct io_cancel_data *cd,
 	io_ring_submit_lock(ctx, issue_flags);
 	ret = -ENOENT;
 	list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
-		struct io_uring_task *tctx = node->task->io_uring;
-
-		ret = io_async_cancel_one(tctx, cd);
+		ret = io_async_cancel_one(node->task->io_uring, cd);
 		if (ret != -ENOENT) {
 			if (!all)
 				break;
diff --git a/io_uring/fdinfo.c b/io_uring/fdinfo.c
index 8d444dd1b0a7..b1e0e0d85349 100644
--- a/io_uring/fdinfo.c
+++ b/io_uring/fdinfo.c
@@ -50,9 +50,9 @@ static __cold int io_uring_show_cred(struct seq_file *m, unsigned int id,
  * Caller holds a reference to the file already, we don't need to do
  * anything else to get an extra reference.
  */
-__cold void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
+__cold void io_uring_show_fdinfo(struct seq_file *m, struct file *file)
 {
-	struct io_ring_ctx *ctx = f->private_data;
+	struct io_ring_ctx *ctx = file->private_data;
 	struct io_overflow_cqe *ocqe;
 	struct io_rings *r = ctx->rings;
 	struct rusage sq_usage;
diff --git a/io_uring/register.c b/io_uring/register.c
index 99c37775f974..ef8c908346a4 100644
--- a/io_uring/register.c
+++ b/io_uring/register.c
@@ -368,8 +368,7 @@ static __cold int io_register_iowq_max_workers(struct io_ring_ctx *ctx,
 
 	/* now propagate the restriction to all registered users */
 	list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
-		struct io_uring_task *tctx = node->task->io_uring;
-
+		tctx = node->task->io_uring;
 		if (WARN_ON_ONCE(!tctx->io_wq))
 			continue;
 
-- 
2.43.0

-- 
Jens Axboe