Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-24 13:11:40 +00:00
Code Issues Packages Projects Releases Wiki Activity

s390/perf: extend perf_regs support to include floating-point registers

Browse Source 
Extend the perf register support to also export floating-point register
contents for user space tasks.  Floating-point registers might be used
in leaf functions to contain the return address.  Hence, they are required
for proper DWARF unwinding.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-and-tested-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Hendrik Brueckner 2017-11-08 07:30:15 +01:00 committed by Martin Schwidefsky
parent a9fc2db0a8
commit 0da0017f72
2 changed files with 37 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
arch/s390/include/uapi/asm/perf_regs.h
View File

@ -18,6 +18,22 @@ enum perf_event_s390_regs {
PERF_REG_S390_R13,
PERF_REG_S390_R14,
PERF_REG_S390_R15,
PERF_REG_S390_FP0,
PERF_REG_S390_FP1,
PERF_REG_S390_FP2,
PERF_REG_S390_FP3,
PERF_REG_S390_FP4,
PERF_REG_S390_FP5,
PERF_REG_S390_FP6,
PERF_REG_S390_FP7,
PERF_REG_S390_FP8,
PERF_REG_S390_FP9,
PERF_REG_S390_FP10,
PERF_REG_S390_FP11,
PERF_REG_S390_FP12,
PERF_REG_S390_FP13,
PERF_REG_S390_FP14,
PERF_REG_S390_FP15,
PERF_REG_S390_MASK,
PERF_REG_S390_PC,

21
arch/s390/kernel/perf_regs.c
View File

@ -4,12 +4,29 @@
#include <linux/errno.h>
#include <linux/bug.h>
#include <asm/ptrace.h>
#include <asm/fpu/api.h>
#include <asm/fpu/types.h>
u64 perf_reg_value(struct pt_regs *regs, int idx)
{
freg_t fp;
if (WARN_ON_ONCE((u32)idx >= PERF_REG_S390_MAX))
return 0;
if (idx >= PERF_REG_S390_R0 && idx <= PERF_REG_S390_R15)
return regs->gprs[idx];
if (idx >= PERF_REG_S390_FP0 && idx <= PERF_REG_S390_FP15) {
if (!user_mode(regs))
return 0;
idx -= PERF_REG_S390_FP0;
fp = MACHINE_HAS_VX ? *(freg_t *)(current->thread.fpu.vxrs + idx)
: current->thread.fpu.fprs[idx];
return fp.ui;
}
if (idx == PERF_REG_S390_MASK)
return regs->psw.mask;
if (idx == PERF_REG_S390_PC)
@ -43,7 +60,11 @@ void perf_get_regs_user(struct perf_regs *regs_user,
/*
* Use the regs from the first interruption and let
* perf_sample_regs_intr() handle interrupts (regs == get_irq_regs()).
*
* Also save FPU registers for user-space tasks only.
*/
regs_user->regs = task_pt_regs(current);
if (user_mode(regs_user->regs))
save_fpu_regs();
regs_user->abi = perf_reg_abi(current);
}