| Message ID | 20240130233526.1031801-4-dave.jiang@intel.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [NDCTL,v4,1/4] ndctl: cxl: Add QoS class retrieval for the root decoder | expand |
On Tue, Jan 30, 2024 at 04:32:43PM -0700, Dave Jiang wrote: > The CFMWS provides a QTG ID. The kernel driver creates a root decoder that > represents the CFMWS. A qos_class attribute is exported via sysfs for the root > decoder. > > One or more QoS class tokens are retrieved via QTG ID _DSM from the ACPI0017 > device for a CXL memory device. The input for the _DSM is the read and write > latency and bandwidth for the path between the device and the CPU. The > numbers are constructed by the kernel driver for the _DSM input. When a > device is probed, QoS class tokens are retrieved. This is useful for a > hot-plugged CXL memory device that does not have regions created. > > Add a QoS check during region creation. Emit a warning if the qos_class > token from the root decoder is different than the mem device qos_class > token. User parameter options are provided to fail instead of just > warning. > > Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> > --- > v4: > - Deal with single memdev qos_class due to kernel change > - Clarify commit log verbiage (Alison) > --- > Documentation/cxl/cxl-create-region.txt | 9 ++++ > cxl/region.c | 56 ++++++++++++++++++++++++- > 2 files changed, 64 insertions(+), 1 deletion(-) > > diff --git a/Documentation/cxl/cxl-create-region.txt b/Documentation/cxl/cxl-create-region.txt > index f11a412bddfe..d5e34cf38236 100644 > --- a/Documentation/cxl/cxl-create-region.txt > +++ b/Documentation/cxl/cxl-create-region.txt > @@ -105,6 +105,15 @@ include::bus-option.txt[] > supplied, the first cross-host bridge (if available), decoder that > supports the largest interleave will be chosen. > > +-e:: > +--strict:: > + Enforce strict execution where any potential error will force failure. > + For example, if qos_class mismatches region creation will fail. > + > +-q:: > +--no-enforce-qos:: > + Parameter to bypass qos_class mismatch failure. Will only emit warning. > + > include::human-option.txt[] > > include::debug-option.txt[] > diff --git a/cxl/region.c b/cxl/region.c > index 3a762db4800e..f9033fa0afbf 100644 > --- a/cxl/region.c > +++ b/cxl/region.c > @@ -32,6 +32,8 @@ static struct region_params { > bool force; > bool human; > bool debug; > + bool strict; > + bool no_qos; > } param = { > .ways = INT_MAX, > .granularity = INT_MAX, > @@ -49,6 +51,8 @@ struct parsed_params { > const char **argv; > struct cxl_decoder *root_decoder; > enum cxl_decoder_mode mode; > + bool strict; > + bool no_qos; > }; > > enum region_actions { > @@ -81,7 +85,9 @@ OPT_STRING('U', "uuid", ¶m.uuid, \ > "region uuid", "uuid for the new region (default: autogenerate)"), \ > OPT_BOOLEAN('m', "memdevs", ¶m.memdevs, \ > "non-option arguments are memdevs"), \ > -OPT_BOOLEAN('u', "human", ¶m.human, "use human friendly number formats") > +OPT_BOOLEAN('u', "human", ¶m.human, "use human friendly number formats"), \ > +OPT_BOOLEAN('e', "strict", ¶m.strict, "strict execution enforcement"), \ > +OPT_BOOLEAN('q', "no-enforce-qos", ¶m.no_qos, "no enforce of qos_class") > > static const struct option create_options[] = { > BASE_OPTIONS(), > @@ -360,6 +366,9 @@ static int parse_create_options(struct cxl_ctx *ctx, int count, > } > } > > + p->strict = param.strict; > + p->no_qos = param.no_qos; > + > return 0; > > err: > @@ -467,6 +476,49 @@ static void set_type_from_decoder(struct cxl_ctx *ctx, struct parsed_params *p) > p->mode = CXL_DECODER_MODE_PMEM; > } > > +static int create_region_validate_qos_class(struct cxl_ctx *ctx, > + struct parsed_params *p) > +{ > + int root_qos_class; > + int qos_class; > + int i; > + > + root_qos_class = cxl_root_decoder_get_qos_class(p->root_decoder); > + if (root_qos_class == CXL_QOS_CLASS_NONE) > + return 0; > + > + for (i = 0; i < p->ways; i++) { > + struct json_object *jobj = > + json_object_array_get_idx(p->memdevs, i); > + struct cxl_memdev *memdev = json_object_get_userdata(jobj); > + > + if (p->mode == CXL_DECODER_MODE_RAM) > + qos_class = cxl_memdev_get_ram_qos_class(memdev); > + else > + qos_class = cxl_memdev_get_pmem_qos_class(memdev); > + > + /* No qos_class entries. Possibly no kernel support */ > + if (qos_class == CXL_QOS_CLASS_NONE) > + break; > + > + if (qos_class != root_qos_class) { > + if (p->strict && !p->no_qos) { > + log_err(&rl, "%s QoS Class mismatches %s\n", > + cxl_decoder_get_devname(p->root_decoder), > + cxl_memdev_get_devname(memdev)); > + > + return -ENXIO; > + } > + > + log_notice(&rl, "%s QoS Class mismatches %s\n", > + cxl_decoder_get_devname(p->root_decoder), > + cxl_memdev_get_devname(memdev)); > + } > + } > + > + return 0; > +} > + > static int create_region_validate_config(struct cxl_ctx *ctx, > struct parsed_params *p) > { > @@ -507,6 +559,8 @@ found: > return rc; > > collect_minsize(ctx, p); > + create_region_validate_qos_class(ctx, p); > + > return 0; > } > > -- > 2.43.0 > >
diff --git a/Documentation/cxl/cxl-create-region.txt b/Documentation/cxl/cxl-create-region.txt index f11a412bddfe..d5e34cf38236 100644 --- a/Documentation/cxl/cxl-create-region.txt +++ b/Documentation/cxl/cxl-create-region.txt @@ -105,6 +105,15 @@ include::bus-option.txt[] supplied, the first cross-host bridge (if available), decoder that supports the largest interleave will be chosen. +-e:: +--strict:: + Enforce strict execution where any potential error will force failure. + For example, if qos_class mismatches region creation will fail. + +-q:: +--no-enforce-qos:: + Parameter to bypass qos_class mismatch failure. Will only emit warning. + include::human-option.txt[] include::debug-option.txt[] diff --git a/cxl/region.c b/cxl/region.c index 3a762db4800e..f9033fa0afbf 100644 --- a/cxl/region.c +++ b/cxl/region.c @@ -32,6 +32,8 @@ static struct region_params { bool force; bool human; bool debug; + bool strict; + bool no_qos; } param = { .ways = INT_MAX, .granularity = INT_MAX, @@ -49,6 +51,8 @@ struct parsed_params { const char **argv; struct cxl_decoder *root_decoder; enum cxl_decoder_mode mode; + bool strict; + bool no_qos; }; enum region_actions { @@ -81,7 +85,9 @@ OPT_STRING('U', "uuid", ¶m.uuid, \ "region uuid", "uuid for the new region (default: autogenerate)"), \ OPT_BOOLEAN('m', "memdevs", ¶m.memdevs, \ "non-option arguments are memdevs"), \ -OPT_BOOLEAN('u', "human", ¶m.human, "use human friendly number formats") +OPT_BOOLEAN('u', "human", ¶m.human, "use human friendly number formats"), \ +OPT_BOOLEAN('e', "strict", ¶m.strict, "strict execution enforcement"), \ +OPT_BOOLEAN('q', "no-enforce-qos", ¶m.no_qos, "no enforce of qos_class") static const struct option create_options[] = { BASE_OPTIONS(), @@ -360,6 +366,9 @@ static int parse_create_options(struct cxl_ctx *ctx, int count, } } + p->strict = param.strict; + p->no_qos = param.no_qos; + return 0; err: @@ -467,6 +476,49 @@ static void set_type_from_decoder(struct cxl_ctx *ctx, struct parsed_params *p) p->mode = CXL_DECODER_MODE_PMEM; } +static int create_region_validate_qos_class(struct cxl_ctx *ctx, + struct parsed_params *p) +{ + int root_qos_class; + int qos_class; + int i; + + root_qos_class = cxl_root_decoder_get_qos_class(p->root_decoder); + if (root_qos_class == CXL_QOS_CLASS_NONE) + return 0; + + for (i = 0; i < p->ways; i++) { + struct json_object *jobj = + json_object_array_get_idx(p->memdevs, i); + struct cxl_memdev *memdev = json_object_get_userdata(jobj); + + if (p->mode == CXL_DECODER_MODE_RAM) + qos_class = cxl_memdev_get_ram_qos_class(memdev); + else + qos_class = cxl_memdev_get_pmem_qos_class(memdev); + + /* No qos_class entries. Possibly no kernel support */ + if (qos_class == CXL_QOS_CLASS_NONE) + break; + + if (qos_class != root_qos_class) { + if (p->strict && !p->no_qos) { + log_err(&rl, "%s QoS Class mismatches %s\n", + cxl_decoder_get_devname(p->root_decoder), + cxl_memdev_get_devname(memdev)); + + return -ENXIO; + } + + log_notice(&rl, "%s QoS Class mismatches %s\n", + cxl_decoder_get_devname(p->root_decoder), + cxl_memdev_get_devname(memdev)); + } + } + + return 0; +} + static int create_region_validate_config(struct cxl_ctx *ctx, struct parsed_params *p) { @@ -507,6 +559,8 @@ found: return rc; collect_minsize(ctx, p); + create_region_validate_qos_class(ctx, p); + return 0; }
The CFMWS provides a QTG ID. The kernel driver creates a root decoder that represents the CFMWS. A qos_class attribute is exported via sysfs for the root decoder. One or more QoS class tokens are retrieved via QTG ID _DSM from the ACPI0017 device for a CXL memory device. The input for the _DSM is the read and write latency and bandwidth for the path between the device and the CPU. The numbers are constructed by the kernel driver for the _DSM input. When a device is probed, QoS class tokens are retrieved. This is useful for a hot-plugged CXL memory device that does not have regions created. Add a QoS check during region creation. Emit a warning if the qos_class token from the root decoder is different than the mem device qos_class token. User parameter options are provided to fail instead of just warning. Signed-off-by: Dave Jiang <dave.jiang@intel.com> --- v4: - Deal with single memdev qos_class due to kernel change - Clarify commit log verbiage (Alison) --- Documentation/cxl/cxl-create-region.txt | 9 ++++ cxl/region.c | 56 ++++++++++++++++++++++++- 2 files changed, 64 insertions(+), 1 deletion(-)