Commit bc43d3af authored by Krzysztof Karas's avatar Krzysztof Karas Committed by Tomasz Zawadzki
Browse files

nvmf_tracing.md: explain how extended -e option works 



This patch modifies documentation page to explain
changes introduced in the previous patch.

Change-Id: If95250004bf8642c941a32a8805e437d6f6c5004
Signed-off-by: default avatarKrzysztof Karas <krzysztof.karas@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/10501


Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
parent 5fed6bd8

doc/nvmf_tracing.md

+48 −5
Original line number Diff line number Diff line
@@ -13,21 +13,64 @@ Work to formalize and document the framework is in progress.) 


## Enabling Tracepoints {#enable_tracepoints}



Tracepoints are placed in groups. They are enabled and disabled as a group. To enable

the instrumentation of all the tracepoints group in an SPDK target application, start the

target with -e parameter set to 0xFFFF:

Tracepoints are placed in groups. They are enabled and disabled as a group or individually

inside a group.



### Enabling Tracepoints in Groups



To enable the instrumentation of all the tracepoints groups in an SPDK target

application, start the target with `-e` parameter set to `0xFFFF` or `all`:



~~~bash

build/bin/nvmf_tgt -e 0xFFFF

~~~



To enable the instrumentation of just the NVMe-oF RDMA tracepoints in an SPDK target

application, start the target with the -e parameter set to 0x10:

or



~~~bash

build/bin/nvmf_tgt -e all

~~~



To enable the instrumentation of just the `NVMe-oF RDMA` tracepoints in an SPDK target

application, start the target with the `-e` parameter set to `0x10`:



~~~bash

build/bin/nvmf_tgt -e 0x10

~~~



### Enabling Individual Tracepoints



To enable individual tracepoints inside a group:



~~~bash

build/bin/nvmf_tgt -e 0x10:B

~~~



or



~~~bash

build/bin/nvmf_tgt -e nvmf_rdma:B

~~~



where `:` is a separator and `B` is the tracepoint mask. This will enable only the first, second and fourth (binary: 1011) tracepoint inside `NVMe-oF RDMA` group.



### Combining Tracepoint Masks



It is also possible to combine enabling whole groups of tpoints and individual ones:



~~~bash

build/bin/nvmf_tgt -e 0x10:2,0x400

~~~



This will enable the second tracepoint inside `NVMe-oF RDMA` group (0x10) and all of the tracepoints defined by the `thread` group (0x400).



### Tracepoint Group Values



iscsi (0x2), scsi (0x4), bdev (0x8), nvmf_rdma (0x10), nvmf_tcp (0x20), ftl (0x40), blobfs (0x80), nvmf_fc (0x100),

idxd (0x200), thread (0x400), nvme_pcie (0x800)



### Starting the SPDK Target



When the target starts, a message is logged with the information you need to view

the tracepoints in a human-readable format using the spdk_trace application. The target

will also log information about the shared memory file.