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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
commit34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch)
tree7629759c1ec7148b95bc8ab3080df20a5ecd2273 /drivers/firmware/google/cbmem.c
downloadlinux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz
linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'drivers/firmware/google/cbmem.c')
-rw-r--r--drivers/firmware/google/cbmem.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/firmware/google/cbmem.c b/drivers/firmware/google/cbmem.c
new file mode 100644
index 000000000..4d20477ed
--- /dev/null
+++ b/drivers/firmware/google/cbmem.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * cbmem.c
+ *
+ * Driver for exporting cbmem entries in sysfs.
+ *
+ * Copyright 2022 Google LLC
+ */
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/kobject.h>
+#include <linux/device-id/coreboot.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+
+#include "coreboot_table.h"
+
+struct cbmem_entry {
+ char *mem_file_buf;
+ u32 size;
+};
+
+static struct cbmem_entry *to_cbmem_entry(struct kobject *kobj)
+{
+ return dev_get_drvdata(kobj_to_dev(kobj));
+}
+
+static ssize_t mem_read(struct file *filp, struct kobject *kobj,
+ const struct bin_attribute *bin_attr, char *buf, loff_t pos,
+ size_t count)
+{
+ struct cbmem_entry *entry = to_cbmem_entry(kobj);
+
+ return memory_read_from_buffer(buf, count, &pos, entry->mem_file_buf,
+ entry->size);
+}
+
+static ssize_t mem_write(struct file *filp, struct kobject *kobj,
+ const struct bin_attribute *bin_attr, char *buf, loff_t pos,
+ size_t count)
+{
+ struct cbmem_entry *entry = to_cbmem_entry(kobj);
+
+ if (pos < 0 || pos >= entry->size)
+ return -EINVAL;
+ if (count > entry->size - pos)
+ count = entry->size - pos;
+
+ memcpy(entry->mem_file_buf + pos, buf, count);
+ return count;
+}
+static const BIN_ATTR_ADMIN_RW(mem, 0);
+
+static ssize_t address_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct coreboot_device *cbdev = dev_to_coreboot_device(dev);
+
+ return sysfs_emit(buf, "0x%llx\n", cbdev->cbmem_entry.address);
+}
+static DEVICE_ATTR_RO(address);
+
+static ssize_t size_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct coreboot_device *cbdev = dev_to_coreboot_device(dev);
+
+ return sysfs_emit(buf, "0x%x\n", cbdev->cbmem_entry.entry_size);
+}
+static DEVICE_ATTR_RO(size);
+
+static struct attribute *attrs[] = {
+ &dev_attr_address.attr,
+ &dev_attr_size.attr,
+ NULL,
+};
+
+static const struct bin_attribute *const bin_attrs[] = {
+ &bin_attr_mem,
+ NULL,
+};
+
+static const struct attribute_group cbmem_entry_group = {
+ .attrs = attrs,
+ .bin_attrs = bin_attrs,
+};
+
+static const struct attribute_group *dev_groups[] = {
+ &cbmem_entry_group,
+ NULL,
+};
+
+static int cbmem_entry_probe(struct coreboot_device *dev)
+{
+ struct cbmem_entry *entry;
+
+ entry = devm_kzalloc(&dev->dev, sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+
+ dev_set_drvdata(&dev->dev, entry);
+ entry->mem_file_buf = devm_memremap(&dev->dev, dev->cbmem_entry.address,
+ dev->cbmem_entry.entry_size,
+ MEMREMAP_WB);
+ if (IS_ERR(entry->mem_file_buf))
+ return PTR_ERR(entry->mem_file_buf);
+
+ entry->size = dev->cbmem_entry.entry_size;
+
+ return 0;
+}
+
+static const struct coreboot_device_id cbmem_ids[] = {
+ { .tag = LB_TAG_CBMEM_ENTRY },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(coreboot, cbmem_ids);
+
+static struct coreboot_driver cbmem_entry_driver = {
+ .probe = cbmem_entry_probe,
+ .drv = {
+ .name = "cbmem",
+ .dev_groups = dev_groups,
+ },
+ .id_table = cbmem_ids,
+};
+module_coreboot_driver(cbmem_entry_driver);
+
+MODULE_AUTHOR("Jack Rosenthal <jrosenth@chromium.org>");
+MODULE_DESCRIPTION("Driver for exporting CBMEM entries in sysfs");
+MODULE_LICENSE("GPL");