Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted

Pull io_uring fixes from Jens Axboe:

 - Fix a task_work add use-after-free with SQPOLL.

   The sqpoll thread could pop and complete the last request while
   io_req_normal_work_add() was still looking at them after the mpscq
   push.

   Use the same approach as DEFER_TASKRUN to protect from that, holding
   an RCU read lock across the add, and have exit wait for an RCU grace
   period for SQPOLL rings as well.

 - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the
   big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED
   rings

 - Mark the source filter table as COW when cloning bpf filters, so
   registering another filter on the source doesn't modify the shared
   table in place

 - Initialize the task context before running the BPF loop

 - Requeue zcrx multishot receives stopped by a local resource

 - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit)

* tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
  io_uring: fix task_work add use-after-free with SQPOLL
  io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full
  io_uring/zcrx: requeue multishot receives stopped by a local resource
  io_uring: initialize task context before running the BPF loop
  io_uring: zero big_cqe for aux CQEs on CQE32 rings
  io_uring: fix free entry check for 32b CQEs on CQE32 rings
  io_uring: only post the dummy skip CQE on CQE_MIXED rings
  io_uring/bpf_filter: mark source as COW when cloning filters

1 files changed, 64 insertions, 0 deletions

diff --git a/tools/perf/bench/futex.c b/tools/perf/bench/futex.c
new file mode 100644
index 000000000..1968c9d00
--- /dev/null
+++ b/tools/perf/bench/futex.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/prctl.h>
+
+#include "futex.h"
+
+#ifndef PR_FUTEX_HASH
+#define PR_FUTEX_HASH                   78
+# define PR_FUTEX_HASH_SET_SLOTS        1
+# define PR_FUTEX_HASH_GET_SLOTS        2
+#endif // PR_FUTEX_HASH
+
+void futex_set_nbuckets_param(struct bench_futex_parameters *params)
+{
+	int ret;
+
+	if (params->nbuckets < 0)
+		return;
+
+	ret = prctl(PR_FUTEX_HASH, PR_FUTEX_HASH_SET_SLOTS, params->nbuckets, 0);
+	if (ret) {
+		printf("Requesting %d hash buckets failed: %d/%m\n",
+		       params->nbuckets, ret);
+		err(EXIT_FAILURE, "prctl(PR_FUTEX_HASH)");
+	}
+}
+
+void futex_print_nbuckets(struct bench_futex_parameters *params)
+{
+	char *futex_hash_mode;
+	int ret;
+
+	ret = prctl(PR_FUTEX_HASH, PR_FUTEX_HASH_GET_SLOTS);
+	if (params->nbuckets >= 0) {
+		if (ret != params->nbuckets) {
+			if (ret < 0) {
+				printf("Can't query number of buckets: %m\n");
+				err(EXIT_FAILURE, "prctl(PR_FUTEX_HASH)");
+			}
+			printf("Requested number of hash buckets does not currently used.\n");
+			printf("Requested: %d in usage: %d\n", params->nbuckets, ret);
+			err(EXIT_FAILURE, "prctl(PR_FUTEX_HASH)");
+		}
+		if (params->nbuckets == 0)
+			ret = asprintf(&futex_hash_mode, "Futex hashing: global hash");
+		else
+			ret = asprintf(&futex_hash_mode, "Futex hashing: %d hash buckets",
+				       params->nbuckets);
+	} else {
+		if (ret <= 0) {
+			ret = asprintf(&futex_hash_mode, "Futex hashing: global hash");
+		} else {
+			ret = asprintf(&futex_hash_mode, "Futex hashing: auto resized to %d buckets",
+				       ret);
+		}
+	}
+	if (ret < 0)
+		err(EXIT_FAILURE, "ENOMEM, futex_hash_mode");
+	printf("%s\n", futex_hash_mode);
+	free(futex_hash_mode);
+}