diff options
author | Mike Marciniszyn <mike.marciniszyn@intel.com> | 2017-08-28 21:24:10 +0300 |
---|---|---|
committer | Doug Ledford <dledford@redhat.com> | 2017-08-29 02:12:31 +0300 |
commit | 0208da90def5776cef940f9de4ffe6ecef346207 (patch) | |
tree | 05833a7dffa3de7e1eea51a004871ae9780e40d5 /drivers/infiniband/sw/rdmavt/mr.c | |
parent | 557fafe1bfecb50c3da0bc4948ebcbc4d19f1619 (diff) | |
download | linux-0208da90def5776cef940f9de4ffe6ecef346207.tar.xz |
IB/rdmavt: Handle dereg of inuse MRs properly
A destroy of an MR prior to destroying the QP can cause the following
diagnostic if the QP is referencing the MR being de-registered:
hfi1 0000:05:00.0: hfi1_0: rvt_dereg_mr timeout mr ffff8808562108
00 pd ffff880859b20b00
The solution is to when the a non-zero refcount is encountered when
the MR is destroyed the QPs needs to be iterated looking for QPs in
the same PD as the MR. If rvt_qp_mr_clean() detects any such QP
references the rkey/lkey, the QP needs to be put into an error state
via a call to rvt_qp_error() which will trigger the clean up of any
stuck references.
This solution is as specified in IBTA 1.3 Volume 1 11.2.10.5.
[This is reproduced with the 0.4.9 version of qperf and the rc_bw test]
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Diffstat (limited to 'drivers/infiniband/sw/rdmavt/mr.c')
-rw-r--r-- | drivers/infiniband/sw/rdmavt/mr.c | 121 |
1 files changed, 104 insertions, 17 deletions
diff --git a/drivers/infiniband/sw/rdmavt/mr.c b/drivers/infiniband/sw/rdmavt/mr.c index 1b3801f78e78..42713511b53b 100644 --- a/drivers/infiniband/sw/rdmavt/mr.c +++ b/drivers/infiniband/sw/rdmavt/mr.c @@ -441,6 +441,105 @@ bail_umem: } /** + * rvt_dereg_clean_qp_cb - callback from iterator + * @qp - the qp + * @v - the mregion (as u64) + * + * This routine fields the callback for all QPs and + * for QPs in the same PD as the MR will call the + * rvt_qp_mr_clean() to potentially cleanup references. + */ +static void rvt_dereg_clean_qp_cb(struct rvt_qp *qp, u64 v) +{ + struct rvt_mregion *mr = (struct rvt_mregion *)v; + + /* skip PDs that are not ours */ + if (mr->pd != qp->ibqp.pd) + return; + rvt_qp_mr_clean(qp, mr->lkey); +} + +/** + * rvt_dereg_clean_qps - find QPs for reference cleanup + * @mr - the MR that is being deregistered + * + * This routine iterates RC QPs looking for references + * to the lkey noted in mr. + */ +static void rvt_dereg_clean_qps(struct rvt_mregion *mr) +{ + struct rvt_dev_info *rdi = ib_to_rvt(mr->pd->device); + + rvt_qp_iter(rdi, (u64)mr, rvt_dereg_clean_qp_cb); +} + +/** + * rvt_check_refs - check references + * @mr - the megion + * @t - the caller identification + * + * This routine checks MRs holding a reference during + * when being de-registered. + * + * If the count is non-zero, the code calls a clean routine then + * waits for the timeout for the count to zero. + */ +static int rvt_check_refs(struct rvt_mregion *mr, const char *t) +{ + unsigned long timeout; + struct rvt_dev_info *rdi = ib_to_rvt(mr->pd->device); + + if (percpu_ref_is_zero(&mr->refcount)) + return 0; + /* avoid dma mr */ + if (mr->lkey) + rvt_dereg_clean_qps(mr); + timeout = wait_for_completion_timeout(&mr->comp, 5 * HZ); + if (!timeout) { + rvt_pr_err(rdi, + "%s timeout mr %p pd %p lkey %x refcount %ld\n", + t, mr, mr->pd, mr->lkey, + atomic_long_read(&mr->refcount.count)); + rvt_get_mr(mr); + return -EBUSY; + } + return 0; +} + +/** + * rvt_mr_has_lkey - is MR + * @mr - the mregion + * @lkey - the lkey + */ +bool rvt_mr_has_lkey(struct rvt_mregion *mr, u32 lkey) +{ + return mr && lkey == mr->lkey; +} + +/** + * rvt_ss_has_lkey - is mr in sge tests + * @ss - the sge state + * @lkey + * + * This code tests for an MR in the indicated + * sge state. + */ +bool rvt_ss_has_lkey(struct rvt_sge_state *ss, u32 lkey) +{ + int i; + bool rval = false; + + if (!ss->num_sge) + return rval; + /* first one */ + rval = rvt_mr_has_lkey(ss->sge.mr, lkey); + /* any others */ + for (i = 0; !rval && i < ss->num_sge - 1; i++) + rval = rvt_mr_has_lkey(ss->sg_list[i].mr, lkey); + return rval; +} + +/** * rvt_dereg_mr - unregister and free a memory region * @ibmr: the memory region to free * @@ -453,22 +552,14 @@ bail_umem: int rvt_dereg_mr(struct ib_mr *ibmr) { struct rvt_mr *mr = to_imr(ibmr); - struct rvt_dev_info *rdi = ib_to_rvt(ibmr->pd->device); - int ret = 0; - unsigned long timeout; + int ret; rvt_free_lkey(&mr->mr); rvt_put_mr(&mr->mr); /* will set completion if last */ - timeout = wait_for_completion_timeout(&mr->mr.comp, 5 * HZ); - if (!timeout) { - rvt_pr_err(rdi, - "rvt_dereg_mr timeout mr %p pd %p\n", - mr, mr->mr.pd); - rvt_get_mr(&mr->mr); - ret = -EBUSY; + ret = rvt_check_refs(&mr->mr, __func__); + if (ret) goto out; - } rvt_deinit_mregion(&mr->mr); if (mr->umem) ib_umem_release(mr->umem); @@ -761,16 +852,12 @@ int rvt_dealloc_fmr(struct ib_fmr *ibfmr) { struct rvt_fmr *fmr = to_ifmr(ibfmr); int ret = 0; - unsigned long timeout; rvt_free_lkey(&fmr->mr); rvt_put_mr(&fmr->mr); /* will set completion if last */ - timeout = wait_for_completion_timeout(&fmr->mr.comp, 5 * HZ); - if (!timeout) { - rvt_get_mr(&fmr->mr); - ret = -EBUSY; + ret = rvt_check_refs(&fmr->mr, __func__); + if (ret) goto out; - } rvt_deinit_mregion(&fmr->mr); kfree(fmr); out: |