add boot partition size

hc

2023-12-11 d2ccde1c8e90d38cee87a1b0309ad2827f3fd30d

 kernel/Documentation/admin-guide/mm/hugetlbpage.rst
..
..
@@ -100,6 +100,52 @@
100
100
 be specified in bytes with optional scale suffix [kKmMgG].  The default huge
101
101
 page size may be selected with the "default_hugepagesz=<size>" boot parameter.
102
102
 
103
+Hugetlb boot command line parameter semantics
104
+
105
+hugepagesz
106
+	Specify a huge page size.  Used in conjunction with hugepages
107
+	parameter to preallocate a number of huge pages of the specified
108
+	size.  Hence, hugepagesz and hugepages are typically specified in
109
+	pairs such as::
110
+
111
+		hugepagesz=2M hugepages=512
112
+
113
+	hugepagesz can only be specified once on the command line for a
114
+	specific huge page size.  Valid huge page sizes are architecture
115
+	dependent.
116
+hugepages
117
+	Specify the number of huge pages to preallocate.  This typically
118
+	follows a valid hugepagesz or default_hugepagesz parameter.  However,
119
+	if hugepages is the first or only hugetlb command line parameter it
120
+	implicitly specifies the number of huge pages of default size to
121
+	allocate.  If the number of huge pages of default size is implicitly
122
+	specified, it can not be overwritten by a hugepagesz,hugepages
123
+	parameter pair for the default size.
124
+
125
+	For example, on an architecture with 2M default huge page size::
126
+
127
+		hugepages=256 hugepagesz=2M hugepages=512
128
+
129
+	will result in 256 2M huge pages being allocated and a warning message
130
+	indicating that the hugepages=512 parameter is ignored.  If a hugepages
131
+	parameter is preceded by an invalid hugepagesz parameter, it will
132
+	be ignored.
133
+default_hugepagesz
134
+	Specify the default huge page size.  This parameter can
135
+	only be specified once on the command line.  default_hugepagesz can
136
+	optionally be followed by the hugepages parameter to preallocate a
137
+	specific number of huge pages of default size.  The number of default
138
+	sized huge pages to preallocate can also be implicitly specified as
139
+	mentioned in the hugepages section above.  Therefore, on an
140
+	architecture with 2M default huge page size::
141
+
142
+		hugepages=256
143
+		default_hugepagesz=2M hugepages=256
144
+		hugepages=256 default_hugepagesz=2M
145
+
146
+	will all result in 256 2M huge pages being allocated.  Valid default
147
+	huge page size is architecture dependent.
148
+
103
149
 When multiple huge page sizes are supported, ``/proc/sys/vm/nr_hugepages``
104
150
 indicates the current number of pre-allocated huge pages of the default size.
105
151
 Thus, one can use the following command to dynamically allocate/deallocate