[PATCH v2] staging: lustre: lnet: revert commit 4671a0266

From: James Simmons
Date: Thu Mar 24 2016 - 11:24:21 EST


Commit 4671a0266 change the parameter of the second parameter of
cfs_precpt_alloc() from a sizeof type to sizeof type *pointer.
This was incorrect in this case and it caused a crash when the LNet
layer was brought up in my testing. The reason is cfs_precpt_alloc()
creates an array of items where the arrays size is equal to the
number of CPTs that exist. Changing to type *pointer only had
cfs_precpt_alloc() create an array of pointers instead of an array
of actual data structures. This patch reverse this change and adds
comments to explain what cfs_precpt_alloc() is actually doing to
avoid potential issues like this again.

Changelog:

v1) Simple revert of the original patch

v2) Added in comments to explain why cfs_precpt_alloc() has the
arguments it uses.

Signed-off-by: James Simmons <jsimmons@xxxxxxxxxxxxx>
---
.../staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c | 14 +++++++++++---
1 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c
index 89f9390..e89c2a1 100644
--- a/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c
+++ b/drivers/staging/lustre/lnet/klnds/o2iblnd/o2iblnd.c
@@ -1965,10 +1965,13 @@ static int kiblnd_net_init_pools(kib_net_t *net, __u32 *cpts, int ncpts)
/*
* premapping can fail if ibd_nmr > 1, so we always create
* FMR pool and map-on-demand if premapping failed
+ *
+ * cfs_precpt_alloc is creating an array of struct kib_fmr_poolset
+ * The number of struct kib_fmr_poolsets create is equal to the
+ * number of CPTs that exist, i.e net->ibn_fmr_ps[cpt].
*/
-
net->ibn_fmr_ps = cfs_percpt_alloc(lnet_cpt_table(),
- sizeof(*net->ibn_fmr_ps));
+ sizeof(kib_fmr_poolset_t));
if (!net->ibn_fmr_ps) {
CERROR("Failed to allocate FMR pool array\n");
rc = -ENOMEM;
@@ -1991,8 +1994,13 @@ static int kiblnd_net_init_pools(kib_net_t *net, __u32 *cpts, int ncpts)
LASSERT(i == ncpts);

create_tx_pool:
+ /*
+ * cfs_precpt_alloc is creating an array of struct kib_tx_poolset
+ * The number of struct kib_tx_poolsets create is equal to the
+ * number of CPTs that exist, i.e net->ibn_tx_ps[cpt].
+ */
net->ibn_tx_ps = cfs_percpt_alloc(lnet_cpt_table(),
- sizeof(*net->ibn_tx_ps));
+ sizeof(kib_tx_poolset_t));
if (!net->ibn_tx_ps) {
CERROR("Failed to allocate tx pool array\n");
rc = -ENOMEM;
--
1.7.1