[PATCH v2 4/4] riscv: pack rv64 thread_info better

Radim Krčmář rkrcmar at ventanamicro.com
Fri Jul 25 09:54:12 PDT 2025


On rv64, preempt_count and cpu were both 32-bit followed by 64-bit, so
placing one in the hole saves 8 bytes in the struct.

Tested-by: Alexandre Ghiti <alexghiti at rivosinc.com>
Reviewed-by: Alexandre Ghiti <alexghiti at rivosinc.com>
Signed-off-by: Radim Krčmář <rkrcmar at ventanamicro.com>
---
v2: tested and reviewed by Alex
---
 arch/riscv/include/asm/thread_info.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h
index f5916a70879a..c267d6bd838e 100644
--- a/arch/riscv/include/asm/thread_info.h
+++ b/arch/riscv/include/asm/thread_info.h
@@ -53,6 +53,7 @@
 struct thread_info {
 	unsigned long		flags;		/* low level flags */
 	int                     preempt_count;  /* 0=>preemptible, <0=>BUG */
+	int			cpu;
 	/*
 	 * These stack pointers are overwritten on every system call or
 	 * exception.  SP is also saved to the stack it can be recovered when
@@ -60,7 +61,6 @@ struct thread_info {
 	 */
 	long			kernel_sp;	/* Kernel stack pointer */
 	long			user_sp;	/* User stack pointer */
-	int			cpu;
 	unsigned long		syscall_work;	/* SYSCALL_WORK_ flags */
 #ifdef CONFIG_SHADOW_CALL_STACK
 	void			*scs_base;
-- 
2.50.0




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