[PATCH v24 2/6] arm64: Use insert_resource() to simplify code

Zhen Lei
2022-05-06T11:45:32Z

insert_resource() traverses the subtree layer by layer from the root node
until a proper location is found. Compared with request_resource(), the
parent node does not need to be determined in advance.

In addition, move the insertion of node 'crashk_res' into function
reserve_crashkernel() to make the associated code close together.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: John Donnelly <john.p.donnelly@oracle.com>
Acked-by: Baoquan He <bhe@redhat.com>
---
arch/arm64/kernel/setup.c | 17 +++--------------
arch/arm64/mm/init.c | 1 +
2 files changed, 4 insertions(+), 14 deletions(-)

diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 3505789cf4bd92a..fea3223704b6339 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -225,6 +225,8 @@ static void __init request_standard_resources(void)
kernel_code.end = __pa_symbol(__init_begin - 1);
kernel_data.start = __pa_symbol(_sdata);
kernel_data.end = __pa_symbol(_end - 1);
+ insert_resource(&iomem_resource, &kernel_code);
+ insert_resource(&iomem_resource, &kernel_data);

num_standard_resources = memblock.memory.cnt;
res_size = num_standard_resources * sizeof(*standard_resources);
@@ -246,20 +248,7 @@ static void __init request_standard_resources(void)
res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
}

- request_resource(&iomem_resource, res);
-
- if (kernel_code.start >= res->start &&
- kernel_code.end <= res->end)
- request_resource(res, &kernel_code);
- if (kernel_data.start >= res->start &&
- kernel_data.end <= res->end)
- request_resource(res, &kernel_data);
-#ifdef CONFIG_KEXEC_CORE
- /* Userspace will find "Crash kernel" region in /proc/iomem. */
- if (crashk_res.end && crashk_res.start >= res->start &&
- crashk_res.end <= res->end)
- request_resource(res, &crashk_res);
-#endif
+ insert_resource(&iomem_resource, res);
}
}

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 1e7b1550e2fcebb..51863f1448c6989 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -137,6 +137,7 @@ static void __init reserve_crashkernel(void)
kmemleak_ignore_phys(crash_base);
crashk_res.start = crash_base;
crashk_res.end = crash_base + crash_size - 1;
+ insert_resource(&iomem_resource, &crashk_res);
}

/*
--
2.25.1