cxl/test: Improve init-order fidelity relative to real-world systems

The investigation of an initialization failure [1] highlighted that
cxl_test does not reflect the init-order of real world systems. The
expected order is root/bus first then async probing of the memory
devices.

Fix up cxl_test to reflect that order. While it did not reproduce the
initial bug report (since that is dependent on built-in vs modular
builds), it did reveal a separate latent bug in the subsystem's decoder
shutdown flow. Fix for that sent separately.

Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://patch.msgid.link/172964784521.81806.15791069994065969243.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>

diff --git a/tools/testing/cxl/test/cxl.c b/tools/testing/cxl/test/cxl.c
index c5bbd89b319209097a96cdf4cd30fd24edb71651..050725afa45d16202b8e92bf7d280d676592007e 100644 (file)
--- a/tools/testing/cxl/test/cxl.c
+++ b/tools/testing/cxl/test/cxl.c
@@ -1058,7 +1058,7 @@ static void mock_companion(struct acpi_device *adev, struct device *dev)
 #define SZ_64G (SZ_32G * 2)
 #endif
 
-static __init int cxl_rch_init(void)
+static __init int cxl_rch_topo_init(void)
 {
        int rc, i;
 
@@ -1086,30 +1086,8 @@ static __init int cxl_rch_init(void)
                        goto err_bridge;
        }
 
-       for (i = 0; i < ARRAY_SIZE(cxl_rcd); i++) {
-               int idx = NR_MEM_MULTI + NR_MEM_SINGLE + i;
-               struct platform_device *rch = cxl_rch[i];
-               struct platform_device *pdev;
-
-               pdev = platform_device_alloc("cxl_rcd", idx);
-               if (!pdev)
-                       goto err_mem;
-               pdev->dev.parent = &rch->dev;
-               set_dev_node(&pdev->dev, i % 2);
-
-               rc = platform_device_add(pdev);
-               if (rc) {
-                       platform_device_put(pdev);
-                       goto err_mem;
-               }
-               cxl_rcd[i] = pdev;
-       }
-
        return 0;
 
-err_mem:
-       for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
-               platform_device_unregister(cxl_rcd[i]);
 err_bridge:
        for (i = ARRAY_SIZE(cxl_rch) - 1; i >= 0; i--) {
                struct platform_device *pdev = cxl_rch[i];
@@ -1123,12 +1101,10 @@ err_bridge:
        return rc;
 }
 
-static void cxl_rch_exit(void)
+static void cxl_rch_topo_exit(void)
 {
        int i;
 
-       for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
-               platform_device_unregister(cxl_rcd[i]);
        for (i = ARRAY_SIZE(cxl_rch) - 1; i >= 0; i--) {
                struct platform_device *pdev = cxl_rch[i];
 
@@ -1139,7 +1115,7 @@ static void cxl_rch_exit(void)
        }
 }
 
-static __init int cxl_single_init(void)
+static __init int cxl_single_topo_init(void)
 {
        int i, rc;
 
@@ -1224,29 +1200,8 @@ static __init int cxl_single_init(void)
                cxl_swd_single[i] = pdev;
        }
 
-       for (i = 0; i < ARRAY_SIZE(cxl_mem_single); i++) {
-               struct platform_device *dport = cxl_swd_single[i];
-               struct platform_device *pdev;
-
-               pdev = platform_device_alloc("cxl_mem", NR_MEM_MULTI + i);
-               if (!pdev)
-                       goto err_mem;
-               pdev->dev.parent = &dport->dev;
-               set_dev_node(&pdev->dev, i % 2);
-
-               rc = platform_device_add(pdev);
-               if (rc) {
-                       platform_device_put(pdev);
-                       goto err_mem;
-               }
-               cxl_mem_single[i] = pdev;
-       }
-
        return 0;
 
-err_mem:
-       for (i = ARRAY_SIZE(cxl_mem_single) - 1; i >= 0; i--)
-               platform_device_unregister(cxl_mem_single[i]);
 err_dport:
        for (i = ARRAY_SIZE(cxl_swd_single) - 1; i >= 0; i--)
                platform_device_unregister(cxl_swd_single[i]);
@@ -1269,12 +1224,10 @@ err_bridge:
        return rc;
 }
 
-static void cxl_single_exit(void)
+static void cxl_single_topo_exit(void)
 {
        int i;
 
-       for (i = ARRAY_SIZE(cxl_mem_single) - 1; i >= 0; i--)
-               platform_device_unregister(cxl_mem_single[i]);
        for (i = ARRAY_SIZE(cxl_swd_single) - 1; i >= 0; i--)
                platform_device_unregister(cxl_swd_single[i]);
        for (i = ARRAY_SIZE(cxl_swu_single) - 1; i >= 0; i--)
@@ -1291,6 +1244,91 @@ static void cxl_single_exit(void)
        }
 }
 
+static void cxl_mem_exit(void)
+{
+       int i;
+
+       for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
+               platform_device_unregister(cxl_rcd[i]);
+       for (i = ARRAY_SIZE(cxl_mem_single) - 1; i >= 0; i--)
+               platform_device_unregister(cxl_mem_single[i]);
+       for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--)
+               platform_device_unregister(cxl_mem[i]);
+}
+
+static int cxl_mem_init(void)
+{
+       int i, rc;
+
+       for (i = 0; i < ARRAY_SIZE(cxl_mem); i++) {
+               struct platform_device *dport = cxl_switch_dport[i];
+               struct platform_device *pdev;
+
+               pdev = platform_device_alloc("cxl_mem", i);
+               if (!pdev)
+                       goto err_mem;
+               pdev->dev.parent = &dport->dev;
+               set_dev_node(&pdev->dev, i % 2);
+
+               rc = platform_device_add(pdev);
+               if (rc) {
+                       platform_device_put(pdev);
+                       goto err_mem;
+               }
+               cxl_mem[i] = pdev;
+       }
+
+       for (i = 0; i < ARRAY_SIZE(cxl_mem_single); i++) {
+               struct platform_device *dport = cxl_swd_single[i];
+               struct platform_device *pdev;
+
+               pdev = platform_device_alloc("cxl_mem", NR_MEM_MULTI + i);
+               if (!pdev)
+                       goto err_single;
+               pdev->dev.parent = &dport->dev;
+               set_dev_node(&pdev->dev, i % 2);
+
+               rc = platform_device_add(pdev);
+               if (rc) {
+                       platform_device_put(pdev);
+                       goto err_single;
+               }
+               cxl_mem_single[i] = pdev;
+       }
+
+       for (i = 0; i < ARRAY_SIZE(cxl_rcd); i++) {
+               int idx = NR_MEM_MULTI + NR_MEM_SINGLE + i;
+               struct platform_device *rch = cxl_rch[i];
+               struct platform_device *pdev;
+
+               pdev = platform_device_alloc("cxl_rcd", idx);
+               if (!pdev)
+                       goto err_rcd;
+               pdev->dev.parent = &rch->dev;
+               set_dev_node(&pdev->dev, i % 2);
+
+               rc = platform_device_add(pdev);
+               if (rc) {
+                       platform_device_put(pdev);
+                       goto err_rcd;
+               }
+               cxl_rcd[i] = pdev;
+       }
+
+       return 0;
+
+err_rcd:
+       for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
+               platform_device_unregister(cxl_rcd[i]);
+err_single:
+       for (i = ARRAY_SIZE(cxl_mem_single) - 1; i >= 0; i--)
+               platform_device_unregister(cxl_mem_single[i]);
+err_mem:
+       for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--)
+               platform_device_unregister(cxl_mem[i]);
+       return rc;
+}
+
 static __init int cxl_test_init(void)
 {
        int rc, i;
@@ -1403,29 +1441,11 @@ static __init int cxl_test_init(void)
                cxl_switch_dport[i] = pdev;
        }
 
-       for (i = 0; i < ARRAY_SIZE(cxl_mem); i++) {
-               struct platform_device *dport = cxl_switch_dport[i];
-               struct platform_device *pdev;
-
-               pdev = platform_device_alloc("cxl_mem", i);
-               if (!pdev)
-                       goto err_mem;
-               pdev->dev.parent = &dport->dev;
-               set_dev_node(&pdev->dev, i % 2);
-
-               rc = platform_device_add(pdev);
-               if (rc) {
-                       platform_device_put(pdev);
-                       goto err_mem;
-               }
-               cxl_mem[i] = pdev;
-       }
-
-       rc = cxl_single_init();
+       rc = cxl_single_topo_init();
        if (rc)
-               goto err_mem;
+               goto err_dport;
 
-       rc = cxl_rch_init();
+       rc = cxl_rch_topo_init();
        if (rc)
                goto err_single;
 
@@ -1438,19 +1458,20 @@ static __init int cxl_test_init(void)
 
        rc = platform_device_add(cxl_acpi);
        if (rc)
-               goto err_add;
+               goto err_root;
+
+       rc = cxl_mem_init();
+       if (rc)
+               goto err_root;
 
        return 0;
 
-err_add:
+err_root:
        platform_device_put(cxl_acpi);
 err_rch:
-       cxl_rch_exit();
+       cxl_rch_topo_exit();
 err_single:
-       cxl_single_exit();
-err_mem:
-       for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--)
-               platform_device_unregister(cxl_mem[i]);
+       cxl_single_topo_exit();
 err_dport:
        for (i = ARRAY_SIZE(cxl_switch_dport) - 1; i >= 0; i--)
                platform_device_unregister(cxl_switch_dport[i]);
@@ -1482,11 +1503,10 @@ static __exit void cxl_test_exit(void)
 {
        int i;
 
+       cxl_mem_exit();
        platform_device_unregister(cxl_acpi);
-       cxl_rch_exit();
-       cxl_single_exit();
-       for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--)
-               platform_device_unregister(cxl_mem[i]);
+       cxl_rch_topo_exit();
+       cxl_single_topo_exit();
        for (i = ARRAY_SIZE(cxl_switch_dport) - 1; i >= 0; i--)
                platform_device_unregister(cxl_switch_dport[i]);
        for (i = ARRAY_SIZE(cxl_switch_uport) - 1; i >= 0; i--)

diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
index ad5c4c18c5c643aff7180a686c1990a136069f6d..71916e0e1546e8f7e1034482e68b28c4edc5a2ea 100644 (file)
--- a/tools/testing/cxl/test/mem.c
+++ b/tools/testing/cxl/test/mem.c
@@ -1673,6 +1673,7 @@ static struct platform_driver cxl_mock_mem_driver = {
                .name = KBUILD_MODNAME,
                .dev_groups = cxl_mock_mem_groups,
                .groups = cxl_mock_mem_core_groups,
+               .probe_type = PROBE_PREFER_ASYNCHRONOUS,
        },
 };