Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/urgent

This commit is contained in:
Ingo Molnar 2011-05-04 20:33:42 +02:00
commit 98bb318864
8 changed files with 74 additions and 12 deletions

View file

@ -767,12 +767,20 @@ long arch_ptrace(struct task_struct *child, long request,
#ifdef CONFIG_HAVE_HW_BREAKPOINT
case PTRACE_GETHBPREGS:
if (ptrace_get_breakpoints(child) < 0)
return -ESRCH;
ret = ptrace_gethbpregs(child, addr,
(unsigned long __user *)data);
ptrace_put_breakpoints(child);
break;
case PTRACE_SETHBPREGS:
if (ptrace_get_breakpoints(child) < 0)
return -ESRCH;
ret = ptrace_sethbpregs(child, addr,
(unsigned long __user *)data);
ptrace_put_breakpoints(child);
break;
#endif

View file

@ -1591,7 +1591,10 @@ long arch_ptrace(struct task_struct *child, long request,
}
case PTRACE_SET_DEBUGREG:
if (ptrace_get_breakpoints(child) < 0)
return -ESRCH;
ret = ptrace_set_debugreg(child, addr, data);
ptrace_put_breakpoints(child);
break;
#ifdef CONFIG_PPC64

View file

@ -117,7 +117,11 @@ void user_enable_single_step(struct task_struct *child)
set_tsk_thread_flag(child, TIF_SINGLESTEP);
if (ptrace_get_breakpoints(child) < 0)
return;
set_single_step(child, pc);
ptrace_put_breakpoints(child);
}
void user_disable_single_step(struct task_struct *child)

View file

@ -608,6 +608,9 @@ static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
unsigned len, type;
struct perf_event *bp;
if (ptrace_get_breakpoints(tsk) < 0)
return -ESRCH;
data &= ~DR_CONTROL_RESERVED;
old_dr7 = ptrace_get_dr7(thread->ptrace_bps);
restore:
@ -655,6 +658,9 @@ restore:
}
goto restore;
}
ptrace_put_breakpoints(tsk);
return ((orig_ret < 0) ? orig_ret : rc);
}
@ -668,10 +674,17 @@ static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n)
if (n < HBP_NUM) {
struct perf_event *bp;
if (ptrace_get_breakpoints(tsk) < 0)
return -ESRCH;
bp = thread->ptrace_bps[n];
if (!bp)
return 0;
val = bp->hw.info.address;
val = 0;
else
val = bp->hw.info.address;
ptrace_put_breakpoints(tsk);
} else if (n == 6) {
val = thread->debugreg6;
} else if (n == 7) {
@ -686,6 +699,10 @@ static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
struct perf_event *bp;
struct thread_struct *t = &tsk->thread;
struct perf_event_attr attr;
int err = 0;
if (ptrace_get_breakpoints(tsk) < 0)
return -ESRCH;
if (!t->ptrace_bps[nr]) {
ptrace_breakpoint_init(&attr);
@ -709,24 +726,23 @@ static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
* writing for the user. And anyway this is the previous
* behaviour.
*/
if (IS_ERR(bp))
return PTR_ERR(bp);
if (IS_ERR(bp)) {
err = PTR_ERR(bp);
goto put;
}
t->ptrace_bps[nr] = bp;
} else {
int err;
bp = t->ptrace_bps[nr];
attr = bp->attr;
attr.bp_addr = addr;
err = modify_user_hw_breakpoint(bp, &attr);
if (err)
return err;
}
return 0;
put:
ptrace_put_breakpoints(tsk);
return err;
}
/*

View file

@ -189,6 +189,10 @@ static inline void ptrace_init_task(struct task_struct *child, bool ptrace)
child->ptrace = current->ptrace;
__ptrace_link(child, current->parent);
}
#ifdef CONFIG_HAVE_HW_BREAKPOINT
atomic_set(&child->ptrace_bp_refcnt, 1);
#endif
}
/**
@ -350,6 +354,13 @@ extern int task_current_syscall(struct task_struct *target, long *callno,
unsigned long args[6], unsigned int maxargs,
unsigned long *sp, unsigned long *pc);
#endif
#ifdef CONFIG_HAVE_HW_BREAKPOINT
extern int ptrace_get_breakpoints(struct task_struct *tsk);
extern void ptrace_put_breakpoints(struct task_struct *tsk);
#else
static inline void ptrace_put_breakpoints(struct task_struct *tsk) { }
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
#endif /* __KERNEL */
#endif

View file

@ -1537,6 +1537,9 @@ struct task_struct {
unsigned long memsw_nr_pages; /* uncharged mem+swap usage */
} memcg_batch;
#endif
#ifdef CONFIG_HAVE_HW_BREAKPOINT
atomic_t ptrace_bp_refcnt;
#endif
};
/* Future-safe accessor for struct task_struct's cpus_allowed. */

View file

@ -1016,7 +1016,7 @@ NORET_TYPE void do_exit(long code)
/*
* FIXME: do that only when needed, using sched_exit tracepoint
*/
flush_ptrace_hw_breakpoint(tsk);
ptrace_put_breakpoints(tsk);
exit_notify(tsk, group_dead);
#ifdef CONFIG_NUMA

View file

@ -22,6 +22,7 @@
#include <linux/syscalls.h>
#include <linux/uaccess.h>
#include <linux/regset.h>
#include <linux/hw_breakpoint.h>
/*
@ -879,3 +880,19 @@ asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
return ret;
}
#endif /* CONFIG_COMPAT */
#ifdef CONFIG_HAVE_HW_BREAKPOINT
int ptrace_get_breakpoints(struct task_struct *tsk)
{
if (atomic_inc_not_zero(&tsk->ptrace_bp_refcnt))
return 0;
return -1;
}
void ptrace_put_breakpoints(struct task_struct *tsk)
{
if (atomic_dec_and_test(&tsk->ptrace_bp_refcnt))
flush_ptrace_hw_breakpoint(tsk);
}
#endif /* CONFIG_HAVE_HW_BREAKPOINT */