[PATCH] btf: Use BIN_ATTR_SIMPLE_RO() to define vmlinux attribute
From: Thomas Weißschuh
Date: Fri Nov 22 2024 - 07:57:30 EST
The usage of the macro allows to remove the custom handler function,
saving some memory. Additionally the code is easier to read.
Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
---
Something similar can be done to btf_module_read() in kernel/bpf/btf.c.
But doing it here and now would lead to some conflicts with some other
sysfs refactorings I'm doing. It will be part of a future series.
---
kernel/bpf/sysfs_btf.c | 21 +++++----------------
1 file changed, 5 insertions(+), 16 deletions(-)
diff --git a/kernel/bpf/sysfs_btf.c b/kernel/bpf/sysfs_btf.c
index fedb54c94cdb830a4890d33677dcc5a6e236c13f..a24381f933d0b80b11116d05463c35e9fa66acb1 100644
--- a/kernel/bpf/sysfs_btf.c
+++ b/kernel/bpf/sysfs_btf.c
@@ -12,34 +12,23 @@
extern char __start_BTF[];
extern char __stop_BTF[];
-static ssize_t
-btf_vmlinux_read(struct file *file, struct kobject *kobj,
- struct bin_attribute *bin_attr,
- char *buf, loff_t off, size_t len)
-{
- memcpy(buf, __start_BTF + off, len);
- return len;
-}
-
-static struct bin_attribute bin_attr_btf_vmlinux __ro_after_init = {
- .attr = { .name = "vmlinux", .mode = 0444, },
- .read = btf_vmlinux_read,
-};
+static __ro_after_init BIN_ATTR_SIMPLE_RO(vmlinux);
struct kobject *btf_kobj;
static int __init btf_vmlinux_init(void)
{
- bin_attr_btf_vmlinux.size = __stop_BTF - __start_BTF;
+ bin_attr_vmlinux.private = __start_BTF;
+ bin_attr_vmlinux.size = __stop_BTF - __start_BTF;
- if (bin_attr_btf_vmlinux.size == 0)
+ if (bin_attr_vmlinux.size == 0)
return 0;
btf_kobj = kobject_create_and_add("btf", kernel_kobj);
if (!btf_kobj)
return -ENOMEM;
- return sysfs_create_bin_file(btf_kobj, &bin_attr_btf_vmlinux);
+ return sysfs_create_bin_file(btf_kobj, &bin_attr_vmlinux);
}
subsys_initcall(btf_vmlinux_init);
---
base-commit: 28eb75e178d389d325f1666e422bc13bbbb9804c
change-id: 20241122-sysfs-const-bin_attr-bpf-737286bb9f27
Best regards,
--
Thomas Weißschuh <linux@xxxxxxxxxxxxxx>