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| author | Gustavo A. R. Silva <gustavoars@kernel.org> | 2020-12-15 20:43:04 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-12-15 22:46:16 -0800 |
| commit | 3a2b67e6e3fdb14c6da4c6909454d7a1d9b24f70 (patch) | |
| tree | abb959ca79cbefc4a26701d674aa85374d854fee | |
| parent | 0ae446e4b91b5a713fb189cf7f23d1a303057fd9 (diff) | |
| download | linux-3a2b67e6e3fdb14c6da4c6909454d7a1d9b24f70.tar.gz linux-3a2b67e6e3fdb14c6da4c6909454d7a1d9b24f70.tar.bz2 linux-3a2b67e6e3fdb14c6da4c6909454d7a1d9b24f70.zip | |
lib/stackdepot.c: replace one-element array with flexible-array member
Patch series "lib/stackdepot.c: Replace one-element array with flexible-array member".
This series aims to replace a one-element array with a flexible-array
member. Also, make use of the struct_size(), flexible_array_size() and
array_size() helpers.
This patch (of 3):
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code
should always use “flexible array members”[1] for these cases. The
older style of one-element or zero-length arrays should no longer be
used[2].
Refactor the code according to the use of a flexible-array member in
struct stack_record, instead of a one-element array, and use the
struct_size() helper to calculate the size for the allocation.
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays
Link: https://lkml.kernel.org/r/cover.1601565471.git.gustavoars@kernel.org
Link: https://lore.kernel.org/lkml/5f75876b.x9zdN10esiC0qLHV%25lkp@intel.com/
Link: https://lkml.kernel.org/r/2f1e6a17aaa891ad9c58817cf0a10b8ab8894f59.1601565471.git.gustavoars@kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | lib/stackdepot.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/lib/stackdepot.c b/lib/stackdepot.c index 2caffc64e4c8..c6106cfb7950 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -62,7 +62,7 @@ struct stack_record { u32 hash; /* Hash in the hastable */ u32 size; /* Number of frames in the stack */ union handle_parts handle; - unsigned long entries[1]; /* Variable-sized array of entries. */ + unsigned long entries[]; /* Variable-sized array of entries. */ }; static void *stack_slabs[STACK_ALLOC_MAX_SLABS]; @@ -104,9 +104,8 @@ static bool init_stack_slab(void **prealloc) static struct stack_record *depot_alloc_stack(unsigned long *entries, int size, u32 hash, void **prealloc, gfp_t alloc_flags) { - int required_size = offsetof(struct stack_record, entries) + - sizeof(unsigned long) * size; struct stack_record *stack; + size_t required_size = struct_size(stack, entries, size); required_size = ALIGN(required_size, 1 << STACK_ALLOC_ALIGN); |