diff options
| author | Brian Gerst <brgerst@gmail.com> | 2025-03-03 11:52:37 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2025-03-04 20:30:33 +0100 |
| commit | 972f9cdff924ca53715019b63b4d4aed69d23b1e (patch) | |
| tree | 9dff5ed5e93f359e37cfea3af5bc4d9c5bd0e431 | |
| parent | ab2bb9c084f7e3b641ceba91efc33b3adcd1846e (diff) | |
x86/percpu: Move pcpu_hot to percpu hot section
Also change the alignment of the percpu hot section:
- PERCPU_SECTION(INTERNODE_CACHE_BYTES)
+ PERCPU_SECTION(L1_CACHE_BYTES)
As vSMP will muck with INTERNODE_CACHE_BYTES that invalidates the
too-large-section assert we do:
ASSERT(__per_cpu_hot_end - __per_cpu_hot_start <= 64, "percpu cache hot section too large")
[ mingo: Added INTERNODE_CACHE_BYTES fix & explanation. ]
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250303165246.2175811-3-brgerst@gmail.com
| -rw-r--r-- | arch/x86/include/asm/current.h | 28 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/vmlinux.lds.S | 5 |
3 files changed, 16 insertions, 19 deletions
diff --git a/arch/x86/include/asm/current.h b/arch/x86/include/asm/current.h index bf5953883ec3..60bc66edca83 100644 --- a/arch/x86/include/asm/current.h +++ b/arch/x86/include/asm/current.h @@ -13,32 +13,26 @@ struct task_struct; struct pcpu_hot { - union { - struct { - struct task_struct *current_task; - int preempt_count; - int cpu_number; + struct task_struct *current_task; + int preempt_count; + int cpu_number; #ifdef CONFIG_MITIGATION_CALL_DEPTH_TRACKING - u64 call_depth; + u64 call_depth; #endif - unsigned long top_of_stack; - void *hardirq_stack_ptr; - u16 softirq_pending; + unsigned long top_of_stack; + void *hardirq_stack_ptr; + u16 softirq_pending; #ifdef CONFIG_X86_64 - bool hardirq_stack_inuse; + bool hardirq_stack_inuse; #else - void *softirq_stack_ptr; + void *softirq_stack_ptr; #endif - }; - u8 pad[64]; - }; }; -static_assert(sizeof(struct pcpu_hot) == 64); -DECLARE_PER_CPU_ALIGNED(struct pcpu_hot, pcpu_hot); +DECLARE_PER_CPU_CACHE_HOT(struct pcpu_hot, pcpu_hot); /* const-qualified alias to pcpu_hot, aliased by linker. */ -DECLARE_PER_CPU_ALIGNED(const struct pcpu_hot __percpu_seg_override, +DECLARE_PER_CPU_CACHE_HOT(const struct pcpu_hot __percpu_seg_override, const_pcpu_hot); static __always_inline struct task_struct *get_current(void) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 88a6707b765c..f00870b2c980 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -2064,7 +2064,7 @@ static __init int setup_setcpuid(char *arg) } __setup("setcpuid=", setup_setcpuid); -DEFINE_PER_CPU_ALIGNED(struct pcpu_hot, pcpu_hot) = { +DEFINE_PER_CPU_CACHE_HOT(struct pcpu_hot, pcpu_hot) = { .current_task = &init_task, .preempt_count = INIT_PREEMPT_COUNT, .top_of_stack = TOP_OF_INIT_STACK, diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 1769a7126224..0ef9870ea52e 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -187,6 +187,8 @@ SECTIONS PAGE_ALIGNED_DATA(PAGE_SIZE) + CACHE_HOT_DATA(L1_CACHE_BYTES) + CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES) DATA_DATA @@ -327,7 +329,8 @@ SECTIONS EXIT_DATA } - PERCPU_SECTION(INTERNODE_CACHE_BYTES) + PERCPU_SECTION(L1_CACHE_BYTES) + ASSERT(__per_cpu_hot_end - __per_cpu_hot_start <= 64, "percpu cache hot section too large") RUNTIME_CONST_VARIABLES RUNTIME_CONST(ptr, USER_PTR_MAX) |