[S390] ptrace cleanup

Overhaul program event recording and the code dealing with the ptrace
user space interface.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 30 insertions, 39 deletions

diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 1c0dce58933a..9d3603d6c511 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -51,7 +51,7 @@ STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
 STACK_SIZE  = 1 << STACK_SHIFT
 
 _TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
-                 _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_SINGLE_STEP )
+                 _TIF_MCCK_PENDING | _TIF_RESTART_SVC | _TIF_PER_TRAP )
 _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
                  _TIF_MCCK_PENDING)
 _TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | \
@@ -208,30 +208,21 @@ _TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | \
  */
         .globl  __switch_to
 __switch_to:
-        tm      __THREAD_per+4(%r3),0xe8 # is the new process using per ?
-        jz      __switch_to_noper               # if not we're fine
-        stctg   %c9,%c11,__SF_EMPTY(%r15)# We are using per stuff
-        clc     __THREAD_per(24,%r3),__SF_EMPTY(%r15)
-        je      __switch_to_noper            # we got away without bashing TLB's
-        lctlg   %c9,%c11,__THREAD_per(%r3)      # Nope we didn't
-__switch_to_noper:
-        lg      %r4,__THREAD_info(%r2)              # get thread_info of prev
+        lg      %r4,__THREAD_info(%r2)          # get thread_info of prev
+        lg      %r5,__THREAD_info(%r3)          # get thread_info of next
         tm      __TI_flags+7(%r4),_TIF_MCCK_PENDING # machine check pending?
-        jz      __switch_to_no_mcck
-        ni      __TI_flags+7(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
-        lg      %r4,__THREAD_info(%r3)              # get thread_info of next
-        oi      __TI_flags+7(%r4),_TIF_MCCK_PENDING # set it in next
-__switch_to_no_mcck:
-        stmg    %r6,%r15,__SF_GPRS(%r15)# store __switch_to registers of prev task
-        stg     %r15,__THREAD_ksp(%r2)  # store kernel stack to prev->tss.ksp
-        lg      %r15,__THREAD_ksp(%r3)  # load kernel stack from next->tss.ksp
-        lmg     %r6,%r15,__SF_GPRS(%r15)# load __switch_to registers of next task
-        stg     %r3,__LC_CURRENT        # __LC_CURRENT = current task struct
-        lctl    %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
-        lg      %r3,__THREAD_info(%r3)  # load thread_info from task struct
-        stg     %r3,__LC_THREAD_INFO
-        aghi    %r3,STACK_SIZE
-        stg     %r3,__LC_KERNEL_STACK   # __LC_KERNEL_STACK = new kernel stack
+        jz      0f
+        ni      __TI_flags+7(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
+        oi      __TI_flags+7(%r5),_TIF_MCCK_PENDING     # set it in next
+0:      stmg    %r6,%r15,__SF_GPRS(%r15)        # store gprs of prev task
+        stg     %r15,__THREAD_ksp(%r2)          # store kernel stack of prev
+        lg      %r15,__THREAD_ksp(%r3)          # load kernel stack of next
+        lctl    %c4,%c4,__TASK_pid(%r3)         # load pid to control reg. 4
+        lmg     %r6,%r15,__SF_GPRS(%r15)        # load gprs of next task
+        stg     %r3,__LC_CURRENT                # store task struct of next
+        stg     %r5,__LC_THREAD_INFO            # store thread info of next
+        aghi    %r5,STACK_SIZE                  # end of kernel stack of next
+        stg     %r5,__LC_KERNEL_STACK           # store end of kernel stack
         br      %r14
 
 __critical_start:
@@ -311,7 +302,7 @@ sysc_work_tif:
         jo      sysc_notify_resume
         tm      __TI_flags+7(%r12),_TIF_RESTART_SVC
         jo      sysc_restart
-        tm      __TI_flags+7(%r12),_TIF_SINGLE_STEP
+        tm      __TI_flags+7(%r12),_TIF_PER_TRAP
         jo      sysc_singlestep
         j       sysc_return             # beware of critical section cleanup
 
@@ -333,12 +324,12 @@ sysc_mcck_pending:
 # _TIF_SIGPENDING is set, call do_signal
 #
 sysc_sigpending:
-        ni      __TI_flags+7(%r12),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
+        ni      __TI_flags+7(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP
         la      %r2,SP_PTREGS(%r15)     # load pt_regs
         brasl   %r14,do_signal          # call do_signal
         tm      __TI_flags+7(%r12),_TIF_RESTART_SVC
         jo      sysc_restart
-        tm      __TI_flags+7(%r12),_TIF_SINGLE_STEP
+        tm      __TI_flags+7(%r12),_TIF_PER_TRAP
         jo      sysc_singlestep
         j       sysc_return
 
@@ -363,14 +354,14 @@ sysc_restart:
         j       sysc_nr_ok              # restart svc
 
 #
-# _TIF_SINGLE_STEP is set, call do_single_step
+# _TIF_PER_TRAP is set, call do_per_trap
 #
 sysc_singlestep:
-        ni      __TI_flags+7(%r12),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
+        ni      __TI_flags+7(%r12),255-_TIF_PER_TRAP    # clear TIF_PER_TRAP
         xc      SP_SVCNR(2,%r15),SP_SVCNR(%r15)         # clear svc number
         la      %r2,SP_PTREGS(%r15)     # address of register-save area
         larl    %r14,sysc_return        # load adr. of system return
-        jg      do_single_step          # branch to do_sigtrap
+        jg      do_per_trap
 
 #
 # call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
@@ -526,10 +517,10 @@ pgm_no_vtime2:
         lg      %r1,__TI_task(%r12)
         tm      SP_PSW+1(%r15),0x01     # kernel per event ?
         jz      kernel_per
-        mvc     __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
-        mvc     __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
-        mvc     __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
-        oi      __TI_flags+7(%r12),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
+        mvc     __THREAD_per_cause(2,%r1),__LC_PER_CAUSE
+        mvc     __THREAD_per_address(8,%r1),__LC_PER_ADDRESS
+        mvc     __THREAD_per_paid(1,%r1),__LC_PER_PAID
+        oi      __TI_flags+7(%r12),_TIF_PER_TRAP # set TIF_PER_TRAP
         lgf     %r3,__LC_PGM_ILC        # load program interruption code
         lg      %r4,__LC_TRANS_EXC_CODE
         REENABLE_IRQS
@@ -558,10 +549,10 @@ pgm_svcper:
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
         LAST_BREAK
         lg      %r8,__TI_task(%r12)
-        mvc     __THREAD_per+__PER_atmid(2,%r8),__LC_PER_ATMID
-        mvc     __THREAD_per+__PER_address(8,%r8),__LC_PER_ADDRESS
-        mvc     __THREAD_per+__PER_access_id(1,%r8),__LC_PER_ACCESS_ID
-        oi      __TI_flags+7(%r12),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
+        mvc     __THREAD_per_cause(2,%r8),__LC_PER_CAUSE
+        mvc     __THREAD_per_address(8,%r8),__LC_PER_ADDRESS
+        mvc     __THREAD_per_paid(1,%r8),__LC_PER_PAID
+        oi      __TI_flags+7(%r12),_TIF_PER_TRAP # set TIF_PER_TRAP
         stosm   __SF_EMPTY(%r15),0x03   # reenable interrupts
         lmg     %r2,%r6,SP_R2(%r15)     # load svc arguments
         j       sysc_do_svc
@@ -573,7 +564,7 @@ kernel_per:
         REENABLE_IRQS
         xc      SP_SVCNR(2,%r15),SP_SVCNR(%r15) # clear svc number
         la      %r2,SP_PTREGS(%r15)     # address of register-save area
-        brasl   %r14,do_single_step
+        brasl   %r14,do_per_trap
         j       pgm_exit
 
 /*