From 15b1a603365c667208a065e6669abe17b7d79763 Mon Sep 17 00:00:00 2001
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Thu, 17 Feb 2022 11:24:01 +0100
Subject: [PATCH] fork, IA64: Provide alloc_thread_stack_node() for IA64
References: SLE Realtime Extension
Patch-mainline: v5.18-rc1
Git-commit: 2bb0529c0bc0698f3baf3e88ffd61a18eef252a7
Provide a generic alloc_thread_stack_node() for IA64/
CONFIG_ARCH_THREAD_STACK_ALLOCATOR which returns stack pointer and sets
task_struct::stack so it behaves exactly like the other implementations.
Rename IA64's alloc_thread_stack_node() and add the generic version to
the fork code so it is in one place _and_ to drastically lower chances
of fat fingering the IA64 code.
Do the same for free_thread_stack().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20220217102406.3697941-4-bigeasy@linutronix.de
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
arch/ia64/include/asm/thread_info.h | 6 +++---
kernel/fork.c | 17 +++++++++++++++++
2 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/arch/ia64/include/asm/thread_info.h b/arch/ia64/include/asm/thread_info.h
index 51d20cb37706..1684716f0820 100644
--- a/arch/ia64/include/asm/thread_info.h
+++ b/arch/ia64/include/asm/thread_info.h
@@ -55,15 +55,15 @@ struct thread_info {
#ifndef ASM_OFFSETS_C
/* how to get the thread information struct from C */
#define current_thread_info() ((struct thread_info *) ((char *) current + IA64_TASK_SIZE))
-#define alloc_thread_stack_node(tsk, node) \
+#define arch_alloc_thread_stack_node(tsk, node) \
((unsigned long *) ((char *) (tsk) + IA64_TASK_SIZE))
#define task_thread_info(tsk) ((struct thread_info *) ((char *) (tsk) + IA64_TASK_SIZE))
#else
#define current_thread_info() ((struct thread_info *) 0)
-#define alloc_thread_stack_node(tsk, node) ((unsigned long *) 0)
+#define arch_alloc_thread_stack_node(tsk, node) ((unsigned long *) 0)
#define task_thread_info(tsk) ((struct thread_info *) 0)
#endif
-#define free_thread_stack(tsk) /* nothing */
+#define arch_free_thread_stack(tsk) /* nothing */
#define task_stack_page(tsk) ((void *)(tsk))
#define __HAVE_THREAD_FUNCTIONS
diff --git a/kernel/fork.c b/kernel/fork.c
index a60d7d928e86..e8ea5e2846c3 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -330,6 +330,23 @@ void thread_stack_cache_init(void)
}
# endif /* THREAD_SIZE >= PAGE_SIZE || defined(CONFIG_VMAP_STACK) */
+#else /* CONFIG_ARCH_THREAD_STACK_ALLOCATOR */
+
+static unsigned long *alloc_thread_stack_node(struct task_struct *tsk, int node)
+{
+ unsigned long *stack;
+
+ stack = arch_alloc_thread_stack_node(tsk, node);
+ tsk->stack = stack;
+ return stack;
+}
+
+static void free_thread_stack(struct task_struct *tsk)
+{
+ arch_free_thread_stack(tsk);
+ tsk->stack = NULL;
+}
+
#endif /* !CONFIG_ARCH_THREAD_STACK_ALLOCATOR */
/* SLAB cache for signal_struct structures (tsk->signal) */