Re: [PATCH v2 1/2] riscv: consolidate __ex_table construction

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 





On 2021/10/20 22:06, Jisheng Zhang wrote:
From: Jisheng Zhang <jszhang@xxxxxxxxxx>

Consolidate all the __ex_table constuction code with a _ASM_EXTABLE
helper.

There should be no functional change as a result of this patch.

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
---
  arch/riscv/include/asm/futex.h   | 12 +++-------
  arch/riscv/include/asm/uaccess.h | 40 +++++++++++---------------------
  2 files changed, 17 insertions(+), 35 deletions(-)

diff --git a/arch/riscv/include/asm/futex.h b/arch/riscv/include/asm/futex.h
index 1b00badb9f87..3191574e135c 100644
--- a/arch/riscv/include/asm/futex.h
+++ b/arch/riscv/include/asm/futex.h
@@ -30,10 +30,7 @@
  	"3:	li %[r],%[e]				\n"	\
  	"	jump 2b,%[t]				\n"	\
  	"	.previous				\n"	\
-	"	.section __ex_table,\"a\"		\n"	\
-	"	.balign " RISCV_SZPTR "			\n"	\
-	"	" RISCV_PTR " 1b, 3b			\n"	\
-	"	.previous				\n"	\
+		_ASM_EXTABLE(1b, 3b)				\
  	: [r] "+r" (ret), [ov] "=&r" (oldval),			\
  	  [u] "+m" (*uaddr), [t] "=&r" (tmp)			\
  	: [op] "Jr" (oparg), [e] "i" (-EFAULT)			\
@@ -103,11 +100,8 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
  	"4:	li %[r],%[e]				\n"
  	"	jump 3b,%[t]				\n"
  	"	.previous				\n"
-	"	.section __ex_table,\"a\"		\n"
-	"	.balign " RISCV_SZPTR "			\n"
-	"	" RISCV_PTR " 1b, 4b			\n"
-	"	" RISCV_PTR " 2b, 4b			\n"
-	"	.previous				\n"
+		_ASM_EXTABLE(1b, 4b)			\
+		_ASM_EXTABLE(2b, 4b)			\
  	: [r] "+r" (ret), [v] "=&r" (val), [u] "+m" (*uaddr), [t] "=&r" (tmp)
  	: [ov] "Jr" (oldval), [nv] "Jr" (newval), [e] "i" (-EFAULT)
  	: "memory");
diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
index f314ff44c48d..35802e72ace8 100644
--- a/arch/riscv/include/asm/uaccess.h
+++ b/arch/riscv/include/asm/uaccess.h
@@ -10,6 +10,12 @@
#include <asm/pgtable.h> /* for TASK_SIZE */ +#define _ASM_EXTABLE(from, to) \
+	"	.pushsection	__ex_table, \"a\"\n"			\
+	"	.balign "	RISCV_SZPTR "	 \n"			\
+	"	" RISCV_PTR	"(" #from "), (" #to ")\n"		\
+	"	.popsection\n"
+

The jump_label mechanism could use this macro too,
see arch/riscv/include/asm/jump_label.h, maybe move the above into asm.h
and also do some replace in next patch ?

Question: the jump label use relative address, but why not trigger the Section mismatch issue?



[Index of Archives]     [Linux&nblp;USB Development]     [Linux Media]     [Video for Linux]     [Linux Audio Users]     [Yosemite Secrets]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux