On Thu, Jun 17, 2021 at 02:59:25PM +0200, Håkon Bugge wrote: > The struct rdma_id_private contains three bit-fields, tos_set, > timeout_set, and min_rnr_timer_set. These are set by accessor > functions without any synchronization. If two or all accessor > functions are invoked in close proximity in time, there will be > Read-Modify-Write from several contexts to the same variable, and the > result will be intermittent. > > Replace with a flag variable and an inline function for set with > appropriate memory barriers and the use of test_bit(). > > Signed-off-by: Håkon Bugge <haakon.bugge@xxxxxxxxxx> > Signed-off-by: Hans Westgaard Ry<hans.westgaard.ry@xxxxxxxxxx> > > --- > v1 -> v2: > * Removed define wizardry and replaced with a set function > with memory barriers. Suggested by Leon. > * Removed zero-initialization of flags, due to kzalloc(), > as suggested by Leon > * Review comments from Stefan implicitly adapted due to > first bullet above > * Moved defines and inline function from header file to > cma.c, as suggested by the undersigned > * Renamed enum to cm_id_priv_flag_bits as suggested by the > undersigned > --- > drivers/infiniband/core/cma.c | 38 +++++++++++++++++++++++++------------- > drivers/infiniband/core/cma_priv.h | 4 +--- > 2 files changed, 26 insertions(+), 16 deletions(-) This patch generates checkpatch warnings. ➜ kernel git:(rdma-next) git checkpatch WARNING: line length of 86 exceeds 80 columns #69: FILE: drivers/infiniband/core/cma.c:1149: + if ((*qp_attr_mask & IB_QP_TIMEOUT) && test_bit(TIMEOUT_SET, &id_priv->flags)) WARNING: line length of 98 exceeds 80 columns #73: FILE: drivers/infiniband/core/cma.c:1152: + if ((*qp_attr_mask & IB_QP_MIN_RNR_TIMER) && test_bit(MIN_RNR_TIMER_SET, &id_priv->flags)) WARNING: line length of 86 exceeds 80 columns #127: FILE: drivers/infiniband/core/cma.c:3048: + u8 tos = test_bit(TOS_SET, &id_priv->flags) ? id_priv->tos : default_roce_tos; WARNING: line length of 84 exceeds 80 columns #136: FILE: drivers/infiniband/core/cma.c:3096: + route->path_rec->packet_life_time = test_bit(TIMEOUT_SET, &id_priv->flags) ? 0001-RDMA-cma-Replace-RMW-with-atomic-bit-ops.patch total: 0 errors, 4 warnings, 118 lines checked Thanks
