x86/percpu: Clean up percpu_stable_op()

Use __pcpu_size_call_return() to simplify this_cpu_read_stable().
Also remove __bad_percpu_size() which is now unused.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dennis Zhou <dennis@kernel.org>
Link: https://lkml.kernel.org/r/20200720204925.3654302-10-ndesaulniers@google.com
This commit is contained in:
Brian Gerst 2020-07-20 13:49:23 -07:00 committed by Thomas Gleixner
parent ebcd580bed
commit c94055fe93

View File

@ -85,7 +85,6 @@
/* For arch-specific code, we can use direct single-insn ops (they
* don't give an lvalue though). */
extern void __bad_percpu_size(void);
#define __pcpu_type_1 u8
#define __pcpu_type_2 u16
@ -167,33 +166,13 @@ do { \
(typeof(_var))(unsigned long) pfo_val__; \
})
#define percpu_stable_op(op, var) \
({ \
typeof(var) pfo_ret__; \
switch (sizeof(var)) { \
case 1: \
asm(op "b "__percpu_arg(P1)",%0" \
: "=q" (pfo_ret__) \
: "p" (&(var))); \
break; \
case 2: \
asm(op "w "__percpu_arg(P1)",%0" \
: "=r" (pfo_ret__) \
: "p" (&(var))); \
break; \
case 4: \
asm(op "l "__percpu_arg(P1)",%0" \
: "=r" (pfo_ret__) \
: "p" (&(var))); \
break; \
case 8: \
asm(op "q "__percpu_arg(P1)",%0" \
: "=r" (pfo_ret__) \
: "p" (&(var))); \
break; \
default: __bad_percpu_size(); \
} \
pfo_ret__; \
#define percpu_stable_op(size, op, _var) \
({ \
__pcpu_type_##size pfo_val__; \
asm(__pcpu_op2_##size(op, __percpu_arg(P[var]), "%[val]") \
: [val] __pcpu_reg_##size("=", pfo_val__) \
: [var] "p" (&(_var))); \
(typeof(_var))(unsigned long) pfo_val__; \
})
/*
@ -258,7 +237,11 @@ do { \
* per-thread variables implemented as per-cpu variables and thus
* stable for the duration of the respective task.
*/
#define this_cpu_read_stable(var) percpu_stable_op("mov", var)
#define this_cpu_read_stable_1(pcp) percpu_stable_op(1, "mov", pcp)
#define this_cpu_read_stable_2(pcp) percpu_stable_op(2, "mov", pcp)
#define this_cpu_read_stable_4(pcp) percpu_stable_op(4, "mov", pcp)
#define this_cpu_read_stable_8(pcp) percpu_stable_op(8, "mov", pcp)
#define this_cpu_read_stable(pcp) __pcpu_size_call_return(this_cpu_read_stable_, pcp)
#define raw_cpu_read_1(pcp) percpu_from_op(1, , "mov", pcp)
#define raw_cpu_read_2(pcp) percpu_from_op(2, , "mov", pcp)