Commit 4a23717a authored by Davidlohr Bueso's avatar Davidlohr Bueso Committed by Linus Torvalds

uprobes: share the i_mmap_rwsem

Both register and unregister call build_map_info() in order to create the
list of mappings before installing or removing breakpoints for every mm
which maps file backed memory.  As such, there is no reason to hold the
i_mmap_rwsem exclusively, so share it and allow concurrent readers to
build the mapping data.
Signed-off-by: default avatarDavidlohr Bueso <dbueso@suse.de>
Acked-by: default avatarSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: default avatar"Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: default avatarHugh Dickins <hughd@google.com>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: default avatarMel Gorman <mgorman@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 3dec0ba0
...@@ -724,7 +724,7 @@ build_map_info(struct address_space *mapping, loff_t offset, bool is_register) ...@@ -724,7 +724,7 @@ build_map_info(struct address_space *mapping, loff_t offset, bool is_register)
int more = 0; int more = 0;
again: again:
i_mmap_lock_write(mapping); i_mmap_lock_read(mapping);
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) { vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
if (!valid_vma(vma, is_register)) if (!valid_vma(vma, is_register))
continue; continue;
...@@ -755,7 +755,7 @@ build_map_info(struct address_space *mapping, loff_t offset, bool is_register) ...@@ -755,7 +755,7 @@ build_map_info(struct address_space *mapping, loff_t offset, bool is_register)
info->mm = vma->vm_mm; info->mm = vma->vm_mm;
info->vaddr = offset_to_vaddr(vma, offset); info->vaddr = offset_to_vaddr(vma, offset);
} }
i_mmap_unlock_write(mapping); i_mmap_unlock_read(mapping);
if (!more) if (!more)
goto out; goto out;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment