+ lib-ida-document-locking-requirements-a-bit-better-v2.patch added to -mm tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The patch titled
     Subject: lib/ida: document locking requirements a bit better
has been added to the -mm tree.  Its filename is
     lib-ida-document-locking-requirements-a-bit-better-v2.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/lib-ida-document-locking-requirements-a-bit-better-v2.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/lib-ida-document-locking-requirements-a-bit-better-v2.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: Daniel Vetter <daniel.vetter@xxxxxxxx>
Subject: lib/ida: document locking requirements a bit better

I wanted to wrap a bunch of ida_simple_get calls into their own locking,
until I dug around and read the original commit message.  Stuff like this
should imo be added to the kernel doc, let's do that.

Link: http://lkml.kernel.org/r/20161027072216.20411-1-daniel.vetter@xxxxxxxx
Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx>
Acked-by: Tejun Heo <tj@xxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 lib/idr.c |   11 +++++++++++
 1 file changed, 11 insertions(+)

diff -puN lib/idr.c~lib-ida-document-locking-requirements-a-bit-better-v2 lib/idr.c
--- a/lib/idr.c~lib-ida-document-locking-requirements-a-bit-better-v2
+++ a/lib/idr.c
@@ -927,6 +927,9 @@ EXPORT_SYMBOL(ida_pre_get);
  * and go back to the ida_pre_get() call.  If the ida is full, it will
  * return %-ENOSPC.
  *
+ * Note that callers must ensure that concurrent access to @ida is not possible.
+ * See ida_simple_get() for a varaint which takes care of locking.
+ *
  * @p_id returns a value in the range @starting_id ... %0x7fffffff.
  */
 int ida_get_new_above(struct ida *ida, int starting_id, int *p_id)
@@ -1073,6 +1076,9 @@ EXPORT_SYMBOL(ida_destroy);
  * Allocates an id in the range start <= id < end, or returns -ENOSPC.
  * On memory allocation failure, returns -ENOMEM.
  *
+ * Compared to ida_get_new_above() this function does its own locking, and
+ * should be used unless there are special requirements.
+ *
  * Use ida_simple_remove() to get rid of an id.
  */
 int ida_simple_get(struct ida *ida, unsigned int start, unsigned int end,
@@ -1119,6 +1125,11 @@ EXPORT_SYMBOL(ida_simple_get);
  * ida_simple_remove - remove an allocated id.
  * @ida: the (initialized) ida.
  * @id: the id returned by ida_simple_get.
+ *
+ * Use to release an id allocated with ida_simple_get().
+ *
+ * Compared to ida_remove() this function does its own locking, and should be
+ * used unless there are special requirements.
  */
 void ida_simple_remove(struct ida *ida, unsigned int id)
 {
_

Patches currently in -mm which might be from daniel.vetter@xxxxxxxx are

lib-ida-document-locking-requirements-a-bit-better-v2.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



[Index of Archives]     [Kernel Archive]     [IETF Annouce]     [DCCP]     [Netdev]     [Networking]     [Security]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux SCSI]
  Powered by Linux