diff options
author | Oleg Nesterov <oleg@redhat.com> | 2012-08-08 17:11:42 +0200 |
---|---|---|
committer | Oleg Nesterov <oleg@redhat.com> | 2012-08-28 18:21:18 +0200 |
commit | f8ac4ec9c064b330dcc49e03c450fe74298c4622 (patch) | |
tree | 62d53120d0289719438d27de5f868c36e136ed28 /include/linux/sched.h | |
parent | 78f7411668aa0b2006d331f6a288416dd91b8e5d (diff) |
uprobes: Introduce MMF_HAS_UPROBES
Add the new MMF_HAS_UPROBES flag. It is set by install_breakpoint()
and it is copied by dup_mmap(), uprobe_pre_sstep_notifier() checks
it to avoid the slow path if the task was never probed. Perhaps it
makes sense to check it in valid_vma(is_register => false) as well.
This needs the new dup_mmap()->uprobe_dup_mmap() hook. We can't use
uprobe_reset_state() or put MMF_HAS_UPROBES into MMF_INIT_MASK, we
need oldmm->mmap_sem to avoid the race with uprobe_register() or
mmap() from another thread.
Currently we never clear this bit, it can be false-positive after
uprobe_unregister() or uprobe_munmap() or if dup_mmap() hits the
probed VM_DONTCOPY vma. But this is fine correctness-wise and has
no effect unless the task hits the non-uprobe breakpoint.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Diffstat (limited to 'include/linux/sched.h')
-rw-r--r-- | include/linux/sched.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index b8c86648a2f..3667c332e61 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -446,6 +446,8 @@ extern int get_dumpable(struct mm_struct *mm); #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ #define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */ +#define MMF_HAS_UPROBES 19 /* might have uprobes */ + #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) struct sighand_struct { |