From: "André Almeida" <andrealmeid@collabora.com>
To: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Darren Hart <dvhart@infradead.org>,
linux-kernel@vger.kernel.org,
Steven Rostedt <rostedt@goodmis.org>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: kernel@collabora.com, krisman@collabora.com,
linux-api@vger.kernel.org, libc-alpha@sourceware.org,
mtk.manpages@gmail.com, "Davidlohr Bueso" <dave@stgolabs.net>,
"André Almeida" <andrealmeid@collabora.com>
Subject: [PATCH 1/4] futex: Prepare for futex_wait_multiple()
Date: Thu, 5 Aug 2021 16:04:02 -0300 [thread overview]
Message-ID: <20210805190405.59110-2-andrealmeid@collabora.com> (raw)
In-Reply-To: <20210805190405.59110-1-andrealmeid@collabora.com>
Make public functions and defines that will be used for
futex_wait_multiple() function in next commit.
Signed-off-by: André Almeida <andrealmeid@collabora.com>
---
include/linux/futex.h | 60 +++++++++++++++++++++++++++++++++++++++++++
kernel/futex.c | 42 +-----------------------------
2 files changed, 61 insertions(+), 41 deletions(-)
diff --git a/include/linux/futex.h b/include/linux/futex.h
index b70df27d7e85..f7a0f4a4b5f0 100644
--- a/include/linux/futex.h
+++ b/include/linux/futex.h
@@ -11,6 +11,22 @@ struct inode;
struct mm_struct;
struct task_struct;
+/*
+ * Futex flags used to encode options to functions and preserve them across
+ * restarts.
+ */
+#ifdef CONFIG_MMU
+# define FLAGS_SHARED 0x01
+#else
+/*
+ * NOMMU does not have per process address space. Let the compiler optimize
+ * code away.
+ */
+# define FLAGS_SHARED 0x00
+#endif
+#define FLAGS_CLOCKRT 0x02
+#define FLAGS_HAS_TIMEOUT 0x04
+
/*
* Futexes are matched on equal values of this key.
* The key type depends on whether it's a shared or private mapping.
@@ -50,8 +66,52 @@ union futex_key {
} both;
};
+/**
+ * struct futex_q - The hashed futex queue entry, one per waiting task
+ * @list: priority-sorted list of tasks waiting on this futex
+ * @task: the task waiting on the futex
+ * @lock_ptr: the hash bucket lock
+ * @key: the key the futex is hashed on
+ * @pi_state: optional priority inheritance state
+ * @rt_waiter: rt_waiter storage for use with requeue_pi
+ * @requeue_pi_key: the requeue_pi target futex key
+ * @bitset: bitset for the optional bitmasked wakeup
+ *
+ * We use this hashed waitqueue, instead of a normal wait_queue_entry_t, so
+ * we can wake only the relevant ones (hashed queues may be shared).
+ *
+ * A futex_q has a woken state, just like tasks have TASK_RUNNING.
+ * It is considered woken when plist_node_empty(&q->list) || q->lock_ptr == 0.
+ * The order of wakeup is always to make the first condition true, then
+ * the second.
+ *
+ * PI futexes are typically woken before they are removed from the hash list via
+ * the rt_mutex code. See unqueue_me_pi().
+ */
+struct futex_q {
+ struct plist_node list;
+
+ struct task_struct *task;
+ spinlock_t *lock_ptr;
+ union futex_key key;
+ struct futex_pi_state *pi_state;
+ struct rt_mutex_waiter *rt_waiter;
+ union futex_key *requeue_pi_key;
+ u32 bitset;
+} __randomize_layout;
+
#define FUTEX_KEY_INIT (union futex_key) { .both = { .ptr = 0ULL } }
+static const struct futex_q futex_q_init = {
+ /* list gets initialized in queue_me()*/
+ .key = FUTEX_KEY_INIT,
+ .bitset = FUTEX_BITSET_MATCH_ANY
+};
+
+inline struct hrtimer_sleeper *
+futex_setup_timer(ktime_t *time, struct hrtimer_sleeper *timeout,
+ int flags, u64 range_ns);
+
#ifdef CONFIG_FUTEX
enum {
FUTEX_STATE_OK,
diff --git a/kernel/futex.c b/kernel/futex.c
index 2ecb07575055..c07cb0f747ac 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -187,46 +187,6 @@ struct futex_pi_state {
union futex_key key;
} __randomize_layout;
-/**
- * struct futex_q - The hashed futex queue entry, one per waiting task
- * @list: priority-sorted list of tasks waiting on this futex
- * @task: the task waiting on the futex
- * @lock_ptr: the hash bucket lock
- * @key: the key the futex is hashed on
- * @pi_state: optional priority inheritance state
- * @rt_waiter: rt_waiter storage for use with requeue_pi
- * @requeue_pi_key: the requeue_pi target futex key
- * @bitset: bitset for the optional bitmasked wakeup
- *
- * We use this hashed waitqueue, instead of a normal wait_queue_entry_t, so
- * we can wake only the relevant ones (hashed queues may be shared).
- *
- * A futex_q has a woken state, just like tasks have TASK_RUNNING.
- * It is considered woken when plist_node_empty(&q->list) || q->lock_ptr == 0.
- * The order of wakeup is always to make the first condition true, then
- * the second.
- *
- * PI futexes are typically woken before they are removed from the hash list via
- * the rt_mutex code. See unqueue_me_pi().
- */
-struct futex_q {
- struct plist_node list;
-
- struct task_struct *task;
- spinlock_t *lock_ptr;
- union futex_key key;
- struct futex_pi_state *pi_state;
- struct rt_mutex_waiter *rt_waiter;
- union futex_key *requeue_pi_key;
- u32 bitset;
-} __randomize_layout;
-
-static const struct futex_q futex_q_init = {
- /* list gets initialized in queue_me()*/
- .key = FUTEX_KEY_INIT,
- .bitset = FUTEX_BITSET_MATCH_ANY
-};
-
/*
* Hash buckets are shared by all the futex_keys that hash to the same
* location. Each key may have multiple futex_q structures, one for each task
@@ -395,7 +355,7 @@ enum futex_access {
* Return: Initialized hrtimer_sleeper structure or NULL if no timeout
* value given
*/
-static inline struct hrtimer_sleeper *
+inline struct hrtimer_sleeper *
futex_setup_timer(ktime_t *time, struct hrtimer_sleeper *timeout,
int flags, u64 range_ns)
{
--
2.32.0
next prev parent reply other threads:[~2021-08-05 19:04 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-05 19:04 [PATCH 0/4] futex2: Add wait on multiple futexes syscall André Almeida
2021-08-05 19:04 ` André Almeida [this message]
2021-08-18 8:22 ` [PATCH 1/4] futex: Prepare for futex_wait_multiple() Thomas Gleixner
2021-08-05 19:04 ` [PATCH 2/4] futex2: Implement vectorized wait André Almeida
2021-08-18 11:00 ` Thomas Gleixner
2021-08-18 16:20 ` Peter Zijlstra
2021-08-18 16:34 ` André Almeida
2021-08-18 19:45 ` Thomas Gleixner
2021-08-19 3:38 ` André Almeida
2021-08-05 19:04 ` [PATCH 3/4] selftests: futex2: Add waitv test André Almeida
2021-08-05 19:04 ` [PATCH 4/4] futex2: Documentation: Document futex_waitv() uAPI André Almeida
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=20210805190405.59110-2-andrealmeid@collabora.com \
--to=andrealmeid@collabora.com \
--cc=bigeasy@linutronix.de \
--cc=dave@stgolabs.net \
--cc=dvhart@infradead.org \
--cc=kernel@collabora.com \
--cc=krisman@collabora.com \
--cc=libc-alpha@sourceware.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=mtk.manpages@gmail.com \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
/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;
as well as URLs for NNTP newsgroup(s).