diff options
Diffstat (limited to 'debian/patches-rt/0290-signals-Allow-rt-tasks-to-cache-one-sigqueue-struct.patch')
-rw-r--r-- | debian/patches-rt/0290-signals-Allow-rt-tasks-to-cache-one-sigqueue-struct.patch | 212 |
1 files changed, 0 insertions, 212 deletions
diff --git a/debian/patches-rt/0290-signals-Allow-rt-tasks-to-cache-one-sigqueue-struct.patch b/debian/patches-rt/0290-signals-Allow-rt-tasks-to-cache-one-sigqueue-struct.patch deleted file mode 100644 index e69c0ea63..000000000 --- a/debian/patches-rt/0290-signals-Allow-rt-tasks-to-cache-one-sigqueue-struct.patch +++ /dev/null @@ -1,212 +0,0 @@ -From b5c15e8a9b4b9a6923dac9e886f827a7630a8852 Mon Sep 17 00:00:00 2001 -From: Thomas Gleixner <tglx@linutronix.de> -Date: Fri, 3 Jul 2009 08:44:56 -0500 -Subject: [PATCH 290/296] signals: Allow rt tasks to cache one sigqueue struct -Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patches-5.10.35-rt39.tar.xz - -To avoid allocation allow rt tasks to cache one sigqueue struct in -task struct. - -Signed-off-by: Thomas Gleixner <tglx@linutronix.de> ---- - include/linux/sched.h | 1 + - include/linux/signal.h | 1 + - kernel/exit.c | 2 +- - kernel/fork.c | 1 + - kernel/signal.c | 69 +++++++++++++++++++++++++++++++++++++++--- - 5 files changed, 69 insertions(+), 5 deletions(-) - -diff --git a/include/linux/sched.h b/include/linux/sched.h -index 28509a37eb71..e688e9307a21 100644 ---- a/include/linux/sched.h -+++ b/include/linux/sched.h -@@ -985,6 +985,7 @@ struct task_struct { - /* Signal handlers: */ - struct signal_struct *signal; - struct sighand_struct __rcu *sighand; -+ struct sigqueue *sigqueue_cache; - sigset_t blocked; - sigset_t real_blocked; - /* Restored if set_restore_sigmask() was used: */ -diff --git a/include/linux/signal.h b/include/linux/signal.h -index b256f9c65661..ebf6c515a7b2 100644 ---- a/include/linux/signal.h -+++ b/include/linux/signal.h -@@ -265,6 +265,7 @@ static inline void init_sigpending(struct sigpending *sig) - } - - extern void flush_sigqueue(struct sigpending *queue); -+extern void flush_task_sigqueue(struct task_struct *tsk); - - /* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */ - static inline int valid_signal(unsigned long sig) -diff --git a/kernel/exit.c b/kernel/exit.c -index d13d67fc5f4e..f5933bd07932 100644 ---- a/kernel/exit.c -+++ b/kernel/exit.c -@@ -152,7 +152,7 @@ static void __exit_signal(struct task_struct *tsk) - * Do this under ->siglock, we can race with another thread - * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals. - */ -- flush_sigqueue(&tsk->pending); -+ flush_task_sigqueue(tsk); - tsk->sighand = NULL; - spin_unlock(&sighand->siglock); - -diff --git a/kernel/fork.c b/kernel/fork.c -index eaa47c928f96..1e97f271ac59 100644 ---- a/kernel/fork.c -+++ b/kernel/fork.c -@@ -2025,6 +2025,7 @@ static __latent_entropy struct task_struct *copy_process( - spin_lock_init(&p->alloc_lock); - - init_sigpending(&p->pending); -+ p->sigqueue_cache = NULL; - - p->utime = p->stime = p->gtime = 0; - #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME -diff --git a/kernel/signal.c b/kernel/signal.c -index fde69283d03f..bad7873f8949 100644 ---- a/kernel/signal.c -+++ b/kernel/signal.c -@@ -20,6 +20,7 @@ - #include <linux/sched/task.h> - #include <linux/sched/task_stack.h> - #include <linux/sched/cputime.h> -+#include <linux/sched/rt.h> - #include <linux/file.h> - #include <linux/fs.h> - #include <linux/proc_fs.h> -@@ -404,13 +405,30 @@ void task_join_group_stop(struct task_struct *task) - task_set_jobctl_pending(task, mask | JOBCTL_STOP_PENDING); - } - -+static inline struct sigqueue *get_task_cache(struct task_struct *t) -+{ -+ struct sigqueue *q = t->sigqueue_cache; -+ -+ if (cmpxchg(&t->sigqueue_cache, q, NULL) != q) -+ return NULL; -+ return q; -+} -+ -+static inline int put_task_cache(struct task_struct *t, struct sigqueue *q) -+{ -+ if (cmpxchg(&t->sigqueue_cache, NULL, q) == NULL) -+ return 0; -+ return 1; -+} -+ - /* - * allocate a new signal queue record - * - this may be called without locks if and only if t == current, otherwise an - * appropriate lock must be held to stop the target task from exiting - */ - static struct sigqueue * --__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit) -+__sigqueue_do_alloc(int sig, struct task_struct *t, gfp_t flags, -+ int override_rlimit, int fromslab) - { - struct sigqueue *q = NULL; - struct user_struct *user; -@@ -432,7 +450,10 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi - rcu_read_unlock(); - - if (override_rlimit || likely(sigpending <= task_rlimit(t, RLIMIT_SIGPENDING))) { -- q = kmem_cache_alloc(sigqueue_cachep, flags); -+ if (!fromslab) -+ q = get_task_cache(t); -+ if (!q) -+ q = kmem_cache_alloc(sigqueue_cachep, flags); - } else { - print_dropped_signal(sig); - } -@@ -449,6 +470,13 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimi - return q; - } - -+static struct sigqueue * -+__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, -+ int override_rlimit) -+{ -+ return __sigqueue_do_alloc(sig, t, flags, override_rlimit, 0); -+} -+ - static void __sigqueue_free(struct sigqueue *q) - { - if (q->flags & SIGQUEUE_PREALLOC) -@@ -458,6 +486,21 @@ static void __sigqueue_free(struct sigqueue *q) - kmem_cache_free(sigqueue_cachep, q); - } - -+static void sigqueue_free_current(struct sigqueue *q) -+{ -+ struct user_struct *up; -+ -+ if (q->flags & SIGQUEUE_PREALLOC) -+ return; -+ -+ up = q->user; -+ if (rt_prio(current->normal_prio) && !put_task_cache(current, q)) { -+ atomic_dec(&up->sigpending); -+ free_uid(up); -+ } else -+ __sigqueue_free(q); -+} -+ - void flush_sigqueue(struct sigpending *queue) - { - struct sigqueue *q; -@@ -470,6 +513,21 @@ void flush_sigqueue(struct sigpending *queue) - } - } - -+/* -+ * Called from __exit_signal. Flush tsk->pending and -+ * tsk->sigqueue_cache -+ */ -+void flush_task_sigqueue(struct task_struct *tsk) -+{ -+ struct sigqueue *q; -+ -+ flush_sigqueue(&tsk->pending); -+ -+ q = get_task_cache(tsk); -+ if (q) -+ kmem_cache_free(sigqueue_cachep, q); -+} -+ - /* - * Flush all pending signals for this kthread. - */ -@@ -594,7 +652,7 @@ static void collect_signal(int sig, struct sigpending *list, kernel_siginfo_t *i - (info->si_code == SI_TIMER) && - (info->si_sys_private); - -- __sigqueue_free(first); -+ sigqueue_free_current(first); - } else { - /* - * Ok, it wasn't in the queue. This must be -@@ -631,6 +689,8 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, kernel_siginfo_t *in - bool resched_timer = false; - int signr; - -+ WARN_ON_ONCE(tsk != current); -+ - /* We only dequeue private signals from ourselves, we don't let - * signalfd steal them - */ -@@ -1835,7 +1895,8 @@ EXPORT_SYMBOL(kill_pid); - */ - struct sigqueue *sigqueue_alloc(void) - { -- struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0); -+ /* Preallocated sigqueue objects always from the slabcache ! */ -+ struct sigqueue *q = __sigqueue_do_alloc(-1, current, GFP_KERNEL, 0, 1); - - if (q) - q->flags |= SIGQUEUE_PREALLOC; --- -2.30.2 - |