The patch titled
Subject: uprobes: share the i_mmap_rwsem
has been added to the -mm tree. Its filename is
uprobes-share-the-i_mmap_rwsem.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/uprobes-share-the-i_mmap_rwsem.patch
echo and later at
echo http://ozlabs.org/~akpm/mmotm/broken-out/uprobes-share-the-i_mmap_rwsem.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Davidlohr Bueso <dave@xxxxxxxxxxxx>
Subject: 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: Davidlohr Bueso <dbueso@xxxxxxx>
Acked-by: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Acked-by: Hugh Dickins <hughd@xxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/events/uprobes.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff -puN kernel/events/uprobes.c~uprobes-share-the-i_mmap_rwsem kernel/events/uprobes.c
--- a/kernel/events/uprobes.c~uprobes-share-the-i_mmap_rwsem
+++ a/kernel/events/uprobes.c
@@ -724,7 +724,7 @@ build_map_info(struct address_space *map
int more = 0;
again:
- i_mmap_lock_write(mapping);
+ i_mmap_lock_read(mapping);
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
if (!valid_vma(vma, is_register))
continue;
@@ -755,7 +755,7 @@ build_map_info(struct address_space *map
info->mm = vma->vm_mm;
info->vaddr = offset_to_vaddr(vma, offset);
}
- i_mmap_unlock_write(mapping);
+ i_mmap_unlock_read(mapping);
if (!more)
goto out;
_
Patches currently in -mm which might be from dave@xxxxxxxxxxxx are
mmfs-introduce-helpers-around-the-i_mmap_mutex.patch
mm-use-new-helper-functions-around-the-i_mmap_mutex.patch
mm-convert-i_mmap_mutex-to-rwsem.patch
mm-rmap-share-the-i_mmap_rwsem.patch
uprobes-share-the-i_mmap_rwsem.patch
mm-xip-share-the-i_mmap_rwsem.patch
mm-memory-failure-share-the-i_mmap_rwsem.patch
mm-nommu-share-the-i_mmap_rwsem.patch
ipc-semc-chance-memory-barrier-in-sem_lock-to-smp_rmb.patch
ipc-semc-chance-memory-barrier-in-sem_lock-to-smp_rmb-fix.patch
ipc-semc-chance-memory-barrier-in-sem_lock-to-smp_rmb-fix-fix.patch
ipc-semc-increase-semmsl-semmni-semopm.patch
ipc-msg-increase-msgmni-remove-scaling.patch
ipc-msg-increase-msgmni-remove-scaling-checkpatch-fixes.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
