Re: [PATCH v5 8/8] hw/mem/cxl_type3: Add CXL RAS Error Injection Support.

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

On Thu, 23 Feb 2023 08:37:46 +0100
Markus Armbruster <armbru@redhat.com> wrote:

> Thomas Huth <thuth@redhat.com> writes:
> 
> > On 22/02/2023 19.16, Philippe Mathieu-Daudé wrote:  
> >> +Thomas (meson) & Marc-André (conditional QAPI)  
> >
> > + Markus
> >  
> >> On 22/2/23 17:49, Jonathan Cameron wrote:  
> 
> [...]
> 
> >>>>>> Doesn't these need
> >>>>>>
> >>>>>>         'if': 'CONFIG_CXL_MEM_DEVICE',
> >>>>>>
> >>>>>> ?  
> >>>>>
> >>>>> If I make this change I get a bunch of
> >>>>>
> >>>>> ./qapi/qapi-types-cxl.h:18:13: error: attempt to use poisoned "CONFIG_CXL_MEM_DEVICE"
> >>>>>      18 | #if defined(CONFIG_CXL_MEM_DEVICE)  
> >>>>
> >>>> Err, I meant the generic CONFIG_CXL, not CONFIG_CXL_MEM_DEVICE.
> >>>>  
> >>>>> It's a target specific define (I think) as built alongside PCI_EXPRESS
> >>>>> Only CXL_ACPI is specifically included by x86 and arm64 (out of tree)
> >>>>>
> >>>>> To be honest though I don't fully understand the QEMU build system so the reason
> >>>>> for the error might be wrong.  
> >>>>
> >>>> You need to restrict to system emulation (the 'have_system' check):  
> >>>
> >>> This doesn't help - still have
> >>> attempt to used poisoned "CONFIG_CXL"  
> >
> > Not sure how the QAPI generator works, but target specific config switches can only be used in target specific json files there, so that's machine-target.json and misc-target.json currently, as far as I know. Not sure how the QAPI generator distinguishes between common and target specific code, though ... just by the "-target" suffix? Maybe Markus or Marc-André can comment on that.  
> 
> Whenever you use a poisoned macro in a conditional, all the code
> generated for this .json file (we call it a "QAPI schema module")
> becomes target-dependent.  The QAPI code generator itself is blissfully
> unaware of this.
> 
> Since target-dependent code needs to be compiled differently, the build
> process needs to be know which modules are target-dependent.  We do this
> in one of the stupidest ways that could possibly work: a module is
> target-dependent if its name ends with "-target".  There are just two
> right now: qapi/machine-target.json and qapi/misc-target.json.
> 
> The logic resides in qapi/meson.build.  Look for
> 
>     if module.endswith('-target')

Thanks for all the pointers.
> 
> Questions?

Is it sensible to make the cxl stuff all target dependent and do the following?
I like that we can get rid of the stubs if we do this but I'm sure there are
disadvantages. Only alternative I can currently see is continue to have
stubs and not make the qmp commands conditional on them doing anything useful.

Note this is on top of my tree so involves more changes - I'll push it down
into the relevant series.

From 551122103cf1f5bb4de8ee005482c72532181439 Mon Sep 17 00:00:00 2001
From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Date: Thu, 23 Feb 2023 14:22:53 +0000
Subject: [PATCH] hw/cxl: Make CXL compilation target specific

---
 hw/cxl/cxl-host-stubs.c            | 15 --------
 hw/cxl/meson.build                 |  6 +---
 hw/mem/cxl_type3.c                 |  3 +-
 hw/mem/cxl_type3_stubs.c           | 58 ------------------------------
 hw/mem/meson.build                 |  8 ++---
 qapi/{cxl.json => cxl-target.json} | 37 +++++++++++++------
 qapi/meson.build                   |  2 +-
 qapi/qapi-schema.json              |  2 +-
 8 files changed, 35 insertions(+), 96 deletions(-)

diff --git a/hw/cxl/cxl-host-stubs.c b/hw/cxl/cxl-host-stubs.c
deleted file mode 100644
index cae4afcdde..0000000000
--- a/hw/cxl/cxl-host-stubs.c
+++ /dev/null
@@ -1,15 +0,0 @@
-/*
- * CXL host parameter parsing routine stubs
- *
- * Copyright (c) 2022 Huawei
- */
-#include "qemu/osdep.h"
-#include "qapi/error.h"
-#include "hw/cxl/cxl.h"
-#include "hw/cxl/cxl_host.h"
-
-void cxl_fmws_link_targets(CXLState *stat, Error **errp) {};
-void cxl_machine_init(Object *obj, CXLState *state) {};
-void cxl_hook_up_pxb_registers(PCIBus *bus, CXLState *state, Error **errp) {};
-
-const MemoryRegionOps cfmws_ops;
diff --git a/hw/cxl/meson.build b/hw/cxl/meson.build
index 99ee564ce8..99eeb84268 100644
--- a/hw/cxl/meson.build
+++ b/hw/cxl/meson.build
@@ -1,4 +1,4 @@
-softmmu_ss.add(when: 'CONFIG_CXL',
+specific_ss.add(when: 'CONFIG_CXL',
                if_true: files(
                    'cxl-component-utils.c',
                    'cxl-device-utils.c',
@@ -8,9 +8,5 @@ softmmu_ss.add(when: 'CONFIG_CXL',
                    'cxl-events.c',
                    'cxl-cpmu.c',
                    'switch-mailbox-cci.c',
-               ),
-               if_false: files(
-                   'cxl-host-stubs.c',
                ))
 
-softmmu_ss.add(when: 'CONFIG_ALL', if_true: files('cxl-host-stubs.c'))
diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c
index 334ce92f5e..cf20fb81ff 100644
--- a/hw/mem/cxl_type3.c
+++ b/hw/mem/cxl_type3.c
@@ -1,7 +1,8 @@
 #include "qemu/osdep.h"
+#include CONFIG_DEVICES
 #include "qemu/units.h"
 #include "qemu/error-report.h"
-#include "qapi/qapi-commands-cxl.h"
+#include "qapi/qapi-commands-cxl-target.h"
 #include "hw/mem/memory-device.h"
 #include "hw/mem/pc-dimm.h"
 #include "hw/pci/pci.h"
diff --git a/hw/mem/cxl_type3_stubs.c b/hw/mem/cxl_type3_stubs.c
deleted file mode 100644
index 2196bd841c..0000000000
--- a/hw/mem/cxl_type3_stubs.c
+++ /dev/null
@@ -1,58 +0,0 @@
-
-#include "qemu/osdep.h"
-#include "qapi/error.h"
-#include "qapi/qapi-commands-cxl.h"
-
-void qmp_cxl_inject_gen_media_event(const char *path, CxlEventLog log,
-                                    uint8_t flags, uint64_t physaddr,
-                                    uint8_t descriptor, uint8_t type,
-                                    uint8_t transaction_type,
-                                    bool has_channel, uint8_t channel,
-                                    bool has_rank, uint8_t rank,
-                                    bool has_device, uint32_t device,
-                                    const char *component_id,
-                                    Error **errp) {}
-
-void qmp_cxl_inject_dram_event(const char *path, CxlEventLog log, uint8_t flags,
-                               uint64_t physaddr, uint8_t descriptor,
-                               uint8_t type, uint8_t transaction_type,
-                               bool has_channel, uint8_t channel,
-                               bool has_rank, uint8_t rank,
-                               bool has_nibble_mask, uint32_t nibble_mask,
-                               bool has_bank_group, uint8_t bank_group,
-                               bool has_bank, uint8_t bank,
-                               bool has_row, uint32_t row,
-                               bool has_column, uint16_t column,
-                               bool has_correction_mask, uint64List *correction_mask,
-                               Error **errp) {}
-
-void qmp_cxl_inject_memory_module_event(const char *path, CxlEventLog log,
-                                        uint8_t flags, uint8_t type,
-                                        uint8_t health_status,
-                                        uint8_t media_status,
-                                        uint8_t additional_status,
-                                        uint8_t life_used,
-                                        int16_t temperature,
-                                        uint32_t dirty_shutdown_count,
-                                        uint32_t corrected_volatile_error_count,
-                                        uint32_t corrected_persistent_error_count,
-                                        Error **errp) {}
-
-void qmp_cxl_inject_poison(const char *path, uint64_t start, uint64_t length,
-                           Error **errp)
-{
-    error_setg(errp, "CXL Type 3 support is not compiled in");
-}
-
-void qmp_cxl_inject_uncorrectable_errors(const char *path,
-                                         CXLUncorErrorRecordList *errors,
-                                         Error **errp)
-{
-    error_setg(errp, "CXL Type 3 support is not compiled in");
-}
-
-void qmp_cxl_inject_correctable_error(const char *path, CxlCorErrorType type,
-                                      Error **errp)
-{
-    error_setg(errp, "CXL Type 3 support is not compiled in");
-}
diff --git a/hw/mem/meson.build b/hw/mem/meson.build
index 56c2618b84..2bdd24512e 100644
--- a/hw/mem/meson.build
+++ b/hw/mem/meson.build
@@ -3,10 +3,10 @@ mem_ss.add(files('memory-device.c'))
 mem_ss.add(when: 'CONFIG_DIMM', if_true: files('pc-dimm.c'))
 mem_ss.add(when: 'CONFIG_NPCM7XX', if_true: files('npcm7xx_mc.c'))
 mem_ss.add(when: 'CONFIG_NVDIMM', if_true: files('nvdimm.c'))
-mem_ss.add(when: 'CONFIG_CXL_MEM_DEVICE', if_true: files('cxl_type3.c'))
-softmmu_ss.add(when: 'CONFIG_CXL_MEM_DEVICE', if_false: files('cxl_type3_stubs.c'))
-softmmu_ss.add(when: 'CONFIG_ALL', if_true: files('cxl_type3_stubs.c'))
+specific_ss.add(when: 'CONFIG_CXL_MEM_DEVICE', if_true: files('cxl_type3.c'))
+#specific_ss.add(when: 'CONFIG_CXL_MEM_DEVICE', if_false: files('cxl_type3_stubs.c'))
+#specific_ss.add(when: 'CONFIG_ALL', if_true: files('cxl_type3_stubs.c'))
 
-softmmu_ss.add_all(when: 'CONFIG_MEM_DEVICE', if_true: mem_ss)
+specific_ss.add_all(when: 'CONFIG_MEM_DEVICE', if_true: mem_ss)
 
 softmmu_ss.add(when: 'CONFIG_SPARSE_MEM', if_true: files('sparse-mem.c'))
diff --git a/qapi/cxl.json b/qapi/cxl-target.json
similarity index 94%
rename from qapi/cxl.json
rename to qapi/cxl-target.json
index 4c029f2807..b3aecea4f0 100644
--- a/qapi/cxl.json
+++ b/qapi/cxl-target.json
@@ -21,7 +21,8 @@
            'warning',
            'failure',
            'fatal'
-           ]
+           ],
+  'if': 'CONFIG_CXL_MEM_DEVICE'
  }
 
 ##
@@ -49,7 +50,9 @@
             'type': 'uint8', 'transaction-type': 'uint8',
             '*channel': 'uint8', '*rank': 'uint8',
             '*device': 'uint32', '*component-id': 'str'
-            }}
+            },
+  'if': 'CONFIG_CXL_MEM_DEVICE'
+ }
 
 ##
 # @cxl-inject-dram-event:
@@ -82,7 +85,9 @@
             '*channel': 'uint8', '*rank': 'uint8', '*nibble-mask': 'uint32',
             '*bank-group': 'uint8', '*bank': 'uint8', '*row': 'uint32',
             '*column': 'uint16', '*correction-mask': [ 'uint64' ]
-           }}
+           },
+  'if': 'CONFIG_CXL_MEM_DEVICE'
+}
 
 ##
 # @cxl-inject-memory-module-event:
@@ -115,7 +120,9 @@
             'dirty-shutdown-count': 'uint32',
             'corrected-volatile-error-count': 'uint32',
             'corrected-persistent-error-count': 'uint32'
-            }}
+            },
+  'if': 'CONFIG_CXL_MEM_DEVICE'
+}
 
 ##
 # @cxl-inject-poison:
@@ -133,7 +140,9 @@
 # Since: 8.0
 ##
 { 'command': 'cxl-inject-poison',
-  'data': { 'path': 'str', 'start': 'uint64', 'length': 'uint64' }}
+  'data': { 'path': 'str', 'start': 'uint64', 'length': 'uint64' },
+  'if': 'CONFIG_CXL_MEM_DEVICE'
+}
 
 ##
 # @CxlUncorErrorType:
@@ -179,8 +188,9 @@
            'internal',
            'cxl-ide-tx',
            'cxl-ide-rx'
-           ]
- }
+           ],
+  'if': 'CONFIG_CXL_MEM_DEVICE'
+}
 
 ##
 # @CXLUncorErrorRecord:
@@ -196,7 +206,8 @@
   'data': {
       'type': 'CxlUncorErrorType',
       'header': [ 'uint32' ]
-  }
+  },
+  'if': 'CONFIG_CXL_MEM_DEVICE'
 }
 
 ##
@@ -212,7 +223,9 @@
 ##
 { 'command': 'cxl-inject-uncorrectable-errors',
   'data': { 'path': 'str',
-             'errors': [ 'CXLUncorErrorRecord' ] }}
+             'errors': [ 'CXLUncorErrorRecord' ] },
+  'if': 'CONFIG_CXL_MEM_DEVICE'
+}
 
 ##
 # @CxlCorErrorType:
@@ -235,7 +248,8 @@
            'retry-threshold',
            'cache-poison-received',
            'mem-poison-received',
-           'physical']
+           'physical'],
+  'if': 'CONFIG_CXL_MEM_DEVICE'
 }
 
 ##
@@ -254,5 +268,6 @@
 { 'command': 'cxl-inject-correctable-error',
   'data': { 'path': 'str',
             'type': 'CxlCorErrorType'
-  }
+           },
+  'if': 'CONFIG_CXL_MEM_DEVICE'
 }
diff --git a/qapi/meson.build b/qapi/meson.build
index 73c3c8c31a..f5b3f36979 100644
--- a/qapi/meson.build
+++ b/qapi/meson.build
@@ -31,7 +31,7 @@ qapi_all_modules = [
   'compat',
   'control',
   'crypto',
-  'cxl',
+  'cxl-target',
   'dump',
   'error',
   'introspect',
diff --git a/qapi/qapi-schema.json b/qapi/qapi-schema.json
index 079f2a402a..a79d84577f 100644
--- a/qapi/qapi-schema.json
+++ b/qapi/qapi-schema.json
@@ -95,4 +95,4 @@
 { 'include': 'pci.json' }
 { 'include': 'stats.json' }
 { 'include': 'virtio.json' }
-{ 'include': 'cxl.json' }
+{ 'include': 'cxl-target.json' }
-- 
2.37.2



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