RDMA/core: Add trace points to follow MR allocation

Track the lifetime of ib_mr objects. Here's sample output from a test run
with NFS/RDMA:

           <...>-361   [009] 79238.772782: mr_alloc:             pd.id=3 mr.id=11 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79238.772812: mr_alloc:             pd.id=3 mr.id=12 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79238.772839: mr_alloc:             pd.id=3 mr.id=13 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79238.772866: mr_alloc:             pd.id=3 mr.id=14 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79238.772893: mr_alloc:             pd.id=3 mr.id=15 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79238.772921: mr_alloc:             pd.id=3 mr.id=16 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79238.772947: mr_alloc:             pd.id=3 mr.id=17 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79238.772974: mr_alloc:             pd.id=3 mr.id=18 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79238.773001: mr_alloc:             pd.id=3 mr.id=19 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79238.773028: mr_alloc:             pd.id=3 mr.id=20 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79238.773055: mr_alloc:             pd.id=3 mr.id=21 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.270942: mr_alloc:             pd.id=3 mr.id=22 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.270975: mr_alloc:             pd.id=3 mr.id=23 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.271007: mr_alloc:             pd.id=3 mr.id=24 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.271036: mr_alloc:             pd.id=3 mr.id=25 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.271067: mr_alloc:             pd.id=3 mr.id=26 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.271095: mr_alloc:             pd.id=3 mr.id=27 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.271121: mr_alloc:             pd.id=3 mr.id=28 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.271153: mr_alloc:             pd.id=3 mr.id=29 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.271181: mr_alloc:             pd.id=3 mr.id=30 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.271208: mr_alloc:             pd.id=3 mr.id=31 type=MEM_REG max_num_sg=30 rc=0
           <...>-361   [009] 79240.271236: mr_alloc:             pd.id=3 mr.id=32 type=MEM_REG max_num_sg=30 rc=0
           <...>-4351  [001] 79242.299400: mr_dereg:             mr.id=32
           <...>-4351  [001] 79242.299467: mr_dereg:             mr.id=31
           <...>-4351  [001] 79242.299554: mr_dereg:             mr.id=30
           <...>-4351  [001] 79242.299615: mr_dereg:             mr.id=29
           <...>-4351  [001] 79242.299684: mr_dereg:             mr.id=28
           <...>-4351  [001] 79242.299748: mr_dereg:             mr.id=27
           <...>-4351  [001] 79242.299812: mr_dereg:             mr.id=26
           <...>-4351  [001] 79242.299874: mr_dereg:             mr.id=25
           <...>-4351  [001] 79242.299944: mr_dereg:             mr.id=24
           <...>-4351  [001] 79242.300009: mr_dereg:             mr.id=23
           <...>-4351  [001] 79242.300190: mr_dereg:             mr.id=22
           <...>-4351  [001] 79242.300263: mr_dereg:             mr.id=21
           <...>-4351  [001] 79242.300326: mr_dereg:             mr.id=20
           <...>-4351  [001] 79242.300388: mr_dereg:             mr.id=19
           <...>-4351  [001] 79242.300450: mr_dereg:             mr.id=18
           <...>-4351  [001] 79242.300516: mr_dereg:             mr.id=17
           <...>-4351  [001] 79242.300629: mr_dereg:             mr.id=16
           <...>-4351  [001] 79242.300718: mr_dereg:             mr.id=15
           <...>-4351  [001] 79242.300784: mr_dereg:             mr.id=14
           <...>-4351  [001] 79242.300879: mr_dereg:             mr.id=13
           <...>-4351  [001] 79242.300945: mr_dereg:             mr.id=12
           <...>-4351  [001] 79242.301012: mr_dereg:             mr.id=11

Some features of the output:
- The lifetime and owner PD of each MR is clearly visible.
- The type of MR is captured, as is the SGE array size.
- Failing MR allocation can be recorded.

Link: https://lore.kernel.org/r/20191218201820.30584.34636.stgit@manet.1015granger.net
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index 289b2f7..47d54c3 100644 (file)
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -52,6 +52,7 @@
 #include <rdma/rw.h>
 
 #include "core_priv.h"
+#include <trace/events/rdma_core.h>
 
 #include <trace/events/rdma_core.h>
 
@@ -1999,6 +2000,7 @@ int ib_dereg_mr_user(struct ib_mr *mr, struct ib_udata *udata)
        struct ib_sig_attrs *sig_attrs = mr->sig_attrs;
        int ret;
 
+       trace_mr_dereg(mr);
        rdma_restrack_del(&mr->res);
        ret = mr->device->ops.dereg_mr(mr, udata);
        if (!ret) {
@@ -2030,11 +2032,16 @@ struct ib_mr *ib_alloc_mr_user(struct ib_pd *pd, enum ib_mr_type mr_type,
 {
        struct ib_mr *mr;
 
-       if (!pd->device->ops.alloc_mr)
-               return ERR_PTR(-EOPNOTSUPP);
+       if (!pd->device->ops.alloc_mr) {
+               mr = ERR_PTR(-EOPNOTSUPP);
+               goto out;
+       }
 
-       if (WARN_ON_ONCE(mr_type == IB_MR_TYPE_INTEGRITY))
-               return ERR_PTR(-EINVAL);
+       if (mr_type == IB_MR_TYPE_INTEGRITY) {
+               WARN_ON_ONCE(1);
+               mr = ERR_PTR(-EINVAL);
+               goto out;
+       }
 
        mr = pd->device->ops.alloc_mr(pd, mr_type, max_num_sg, udata);
        if (!IS_ERR(mr)) {
@@ -2050,6 +2057,8 @@ struct ib_mr *ib_alloc_mr_user(struct ib_pd *pd, enum ib_mr_type mr_type,
                mr->sig_attrs = NULL;
        }
 
+out:
+       trace_mr_alloc(pd, mr_type, max_num_sg, mr);
        return mr;
 }
 EXPORT_SYMBOL(ib_alloc_mr_user);
@@ -2074,21 +2083,27 @@ struct ib_mr *ib_alloc_mr_integrity(struct ib_pd *pd,
        struct ib_sig_attrs *sig_attrs;
 
        if (!pd->device->ops.alloc_mr_integrity ||
-           !pd->device->ops.map_mr_sg_pi)
-               return ERR_PTR(-EOPNOTSUPP);
+           !pd->device->ops.map_mr_sg_pi) {
+               mr = ERR_PTR(-EOPNOTSUPP);
+               goto out;
+       }
 
-       if (!max_num_meta_sg)
-               return ERR_PTR(-EINVAL);
+       if (!max_num_meta_sg) {
+               mr = ERR_PTR(-EINVAL);
+               goto out;
+       }
 
        sig_attrs = kzalloc(sizeof(struct ib_sig_attrs), GFP_KERNEL);
-       if (!sig_attrs)
-               return ERR_PTR(-ENOMEM);
+       if (!sig_attrs) {
+               mr = ERR_PTR(-ENOMEM);
+               goto out;
+       }
 
        mr = pd->device->ops.alloc_mr_integrity(pd, max_num_data_sg,
                                                max_num_meta_sg);
        if (IS_ERR(mr)) {
                kfree(sig_attrs);
-               return mr;
+               goto out;
        }
 
        mr->device = pd->device;
@@ -2102,6 +2117,8 @@ struct ib_mr *ib_alloc_mr_integrity(struct ib_pd *pd,
        mr->type = IB_MR_TYPE_INTEGRITY;
        mr->sig_attrs = sig_attrs;
 
+out:
+       trace_mr_integ_alloc(pd, max_num_data_sg, max_num_meta_sg, mr);
        return mr;
 }
 EXPORT_SYMBOL(ib_alloc_mr_integrity);

diff --git a/include/trace/events/rdma_core.h b/include/trace/events/rdma_core.h
index 08f4815..17642aa 100644 (file)
--- a/include/trace/events/rdma_core.h
+++ b/include/trace/events/rdma_core.h
@@ -266,6 +266,129 @@ TRACE_EVENT(cq_free,
        TP_printk("cq.id=%u", __entry->cq_id)
 );
 
+/**
+ ** Memory Region events
+ **/
+
+/*
+ * enum ib_mr_type, from include/rdma/ib_verbs.h
+ */
+#define IB_MR_TYPE_LIST                                \
+       ib_mr_type_item(MEM_REG)                \
+       ib_mr_type_item(SG_GAPS)                \
+       ib_mr_type_item(DM)                     \
+       ib_mr_type_item(USER)                   \
+       ib_mr_type_item(DMA)                    \
+       ib_mr_type_end(INTEGRITY)
+
+#undef ib_mr_type_item
+#undef ib_mr_type_end
+
+#define ib_mr_type_item(x)     TRACE_DEFINE_ENUM(IB_MR_TYPE_##x);
+#define ib_mr_type_end(x)      TRACE_DEFINE_ENUM(IB_MR_TYPE_##x);
+
+IB_MR_TYPE_LIST
+
+#undef ib_mr_type_item
+#undef ib_mr_type_end
+
+#define ib_mr_type_item(x)     { IB_MR_TYPE_##x, #x },
+#define ib_mr_type_end(x)      { IB_MR_TYPE_##x, #x }
+
+#define rdma_show_ib_mr_type(x) \
+               __print_symbolic(x, IB_MR_TYPE_LIST)
+
+TRACE_EVENT(mr_alloc,
+       TP_PROTO(
+               const struct ib_pd *pd,
+               enum ib_mr_type mr_type,
+               u32 max_num_sg,
+               const struct ib_mr *mr
+       ),
+
+       TP_ARGS(pd, mr_type, max_num_sg, mr),
+
+       TP_STRUCT__entry(
+               __field(u32, pd_id)
+               __field(u32, mr_id)
+               __field(u32, max_num_sg)
+               __field(int, rc)
+               __field(unsigned long, mr_type)
+       ),
+
+       TP_fast_assign(
+               __entry->pd_id = pd->res.id;
+               if (IS_ERR(mr)) {
+                       __entry->mr_id = 0;
+                       __entry->rc = PTR_ERR(mr);
+               } else {
+                       __entry->mr_id = mr->res.id;
+                       __entry->rc = 0;
+               }
+               __entry->max_num_sg = max_num_sg;
+               __entry->mr_type = mr_type;
+       ),
+
+       TP_printk("pd.id=%u mr.id=%u type=%s max_num_sg=%u rc=%d",
+               __entry->pd_id, __entry->mr_id,
+               rdma_show_ib_mr_type(__entry->mr_type),
+               __entry->max_num_sg, __entry->rc)
+);
+
+TRACE_EVENT(mr_integ_alloc,
+       TP_PROTO(
+               const struct ib_pd *pd,
+               u32 max_num_data_sg,
+               u32 max_num_meta_sg,
+               const struct ib_mr *mr
+       ),
+
+       TP_ARGS(pd, max_num_data_sg, max_num_meta_sg, mr),
+
+       TP_STRUCT__entry(
+               __field(u32, pd_id)
+               __field(u32, mr_id)
+               __field(u32, max_num_data_sg)
+               __field(u32, max_num_meta_sg)
+               __field(int, rc)
+       ),
+
+       TP_fast_assign(
+               __entry->pd_id = pd->res.id;
+               if (IS_ERR(mr)) {
+                       __entry->mr_id = 0;
+                       __entry->rc = PTR_ERR(mr);
+               } else {
+                       __entry->mr_id = mr->res.id;
+                       __entry->rc = 0;
+               }
+               __entry->max_num_data_sg = max_num_data_sg;
+               __entry->max_num_meta_sg = max_num_meta_sg;
+       ),
+
+       TP_printk("pd.id=%u mr.id=%u max_num_data_sg=%u max_num_meta_sg=%u rc=%d",
+               __entry->pd_id, __entry->mr_id, __entry->max_num_data_sg,
+               __entry->max_num_meta_sg, __entry->rc)
+);
+
+TRACE_EVENT(mr_dereg,
+       TP_PROTO(
+               const struct ib_mr *mr
+       ),
+
+       TP_ARGS(mr),
+
+       TP_STRUCT__entry(
+               __field(u32, id)
+       ),
+
+       TP_fast_assign(
+               __entry->id = mr->res.id;
+       ),
+
+       TP_printk("mr.id=%u", __entry->id)
+);
+
 #endif /* _TRACE_RDMA_CORE_H */
 
 #include <trace/define_trace.h>