blob: f6f79ec4bee3bc526a764b80cd342c5000db9317 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef ARCH_S390_ENTRY_PERCPU_H
#define ARCH_S390_ENTRY_PERCPU_H
#include <linux/bitfield.h>
#include <linux/percpu.h>
#include <asm/lowcore.h>
#include <asm/ptrace.h>
static __always_inline void percpu_entry(struct pt_regs *regs)
{
struct lowcore *lc = get_lowcore();
regs->cpu = lc->cpu_nr;
regs->percpu_register = lc->percpu_register;
lc->percpu_register = 0;
}
static __always_inline void percpu_exit(struct pt_regs *regs)
{
unsigned char regval, regpcp, regoff, regptr;
struct lowcore *lc = get_lowcore();
if (!regs->percpu_register)
return;
regval = regs->percpu_register;
lc->percpu_register = regval;
/* Migrated to a different CPU? */
if (regs->cpu == lc->cpu_nr)
return;
regpcp = FIELD_GET(PCPU_REG_PCP, regval);
regoff = FIELD_GET(PCPU_REG_OFF, regval);
regptr = regoff + 1;
/*
* Update register 'regoff' with the current CPU's percpu offset,
* and recalculate and update current CPU's percpu variable address
* contained in register 'regptr'.
*/
regs->gprs[regoff] = lc->percpu_offset;
regs->gprs[regptr] = regs->gprs[regpcp] + regs->gprs[regoff];
}
#endif
|
