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authorTony Lindgren <tony@atomide.com>2019-08-13 03:40:10 -0700
committerTony Lindgren <tony@atomide.com>2019-08-13 03:40:10 -0700
commit58e16d792a6a8c6b750f637a4649967fcac853dc (patch)
tree778a940499ecfc6fb2d811dbfef735913d30618a /Documentation/bpf/btf.rst
parentfa8397e45c64e60c80373bc19ee56e42a6bed9b6 (diff)
parenta304f483b6b00d42bde41c45ca52c670945348e2 (diff)
downloadlinux-58e16d792a6a8c6b750f637a4649967fcac853dc.tar.bz2
Merge branch 'ti-sysc-fixes' into fixes
Diffstat (limited to 'Documentation/bpf/btf.rst')
-rw-r--r--Documentation/bpf/btf.rst4
1 files changed, 3 insertions, 1 deletions
diff --git a/Documentation/bpf/btf.rst b/Documentation/bpf/btf.rst
index 8820360d00da..4d565d202ce3 100644
--- a/Documentation/bpf/btf.rst
+++ b/Documentation/bpf/btf.rst
@@ -131,7 +131,7 @@ The following sections detail encoding of each kind.
``btf_type`` is followed by a ``u32`` with the following bits arrangement::
#define BTF_INT_ENCODING(VAL) (((VAL) & 0x0f000000) >> 24)
- #define BTF_INT_OFFSET(VAL) (((VAL & 0x00ff0000)) >> 16)
+ #define BTF_INT_OFFSET(VAL) (((VAL) & 0x00ff0000) >> 16)
#define BTF_INT_BITS(VAL) ((VAL) & 0x000000ff)
The ``BTF_INT_ENCODING`` has the following attributes::
@@ -151,6 +151,7 @@ for the type. The maximum value of ``BTF_INT_BITS()`` is 128.
The ``BTF_INT_OFFSET()`` specifies the starting bit offset to calculate values
for this int. For example, a bitfield struct member has:
+
* btf member bit offset 100 from the start of the structure,
* btf member pointing to an int type,
* the int type has ``BTF_INT_OFFSET() = 2`` and ``BTF_INT_BITS() = 4``
@@ -160,6 +161,7 @@ from bits ``100 + 2 = 102``.
Alternatively, the bitfield struct member can be the following to access the
same bits as the above:
+
* btf member bit offset 102,
* btf member pointing to an int type,
* the int type has ``BTF_INT_OFFSET() = 0`` and ``BTF_INT_BITS() = 4``