Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland...
[sfrench/cifs-2.6.git] / include / asm-generic / vmlinux.lds.h
1 #include <linux/section-names.h>
2
3 #ifndef LOAD_OFFSET
4 #define LOAD_OFFSET 0
5 #endif
6
7 #ifndef VMLINUX_SYMBOL
8 #define VMLINUX_SYMBOL(_sym_) _sym_
9 #endif
10
11 /* Align . to a 8 byte boundary equals to maximum function alignment. */
12 #define ALIGN_FUNCTION()  . = ALIGN(8)
13
14 /* The actual configuration determine if the init/exit sections
15  * are handled as text/data or they can be discarded (which
16  * often happens at runtime)
17  */
18 #ifdef CONFIG_HOTPLUG
19 #define DEV_KEEP(sec)    *(.dev##sec)
20 #define DEV_DISCARD(sec)
21 #else
22 #define DEV_KEEP(sec)
23 #define DEV_DISCARD(sec) *(.dev##sec)
24 #endif
25
26 #ifdef CONFIG_HOTPLUG_CPU
27 #define CPU_KEEP(sec)    *(.cpu##sec)
28 #define CPU_DISCARD(sec)
29 #else
30 #define CPU_KEEP(sec)
31 #define CPU_DISCARD(sec) *(.cpu##sec)
32 #endif
33
34 #if defined(CONFIG_MEMORY_HOTPLUG)
35 #define MEM_KEEP(sec)    *(.mem##sec)
36 #define MEM_DISCARD(sec)
37 #else
38 #define MEM_KEEP(sec)
39 #define MEM_DISCARD(sec) *(.mem##sec)
40 #endif
41
42 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
43 #define MCOUNT_REC()    VMLINUX_SYMBOL(__start_mcount_loc) = .; \
44                         *(__mcount_loc)                         \
45                         VMLINUX_SYMBOL(__stop_mcount_loc) = .;
46 #else
47 #define MCOUNT_REC()
48 #endif
49
50 #ifdef CONFIG_TRACE_BRANCH_PROFILING
51 #define LIKELY_PROFILE()        VMLINUX_SYMBOL(__start_annotated_branch_profile) = .; \
52                                 *(_ftrace_annotated_branch)                           \
53                                 VMLINUX_SYMBOL(__stop_annotated_branch_profile) = .;
54 #else
55 #define LIKELY_PROFILE()
56 #endif
57
58 #ifdef CONFIG_PROFILE_ALL_BRANCHES
59 #define BRANCH_PROFILE()        VMLINUX_SYMBOL(__start_branch_profile) = .;   \
60                                 *(_ftrace_branch)                             \
61                                 VMLINUX_SYMBOL(__stop_branch_profile) = .;
62 #else
63 #define BRANCH_PROFILE()
64 #endif
65
66 #ifdef CONFIG_EVENT_TRACING
67 #define FTRACE_EVENTS() VMLINUX_SYMBOL(__start_ftrace_events) = .;      \
68                         *(_ftrace_events)                               \
69                         VMLINUX_SYMBOL(__stop_ftrace_events) = .;
70 #else
71 #define FTRACE_EVENTS()
72 #endif
73
74 #ifdef CONFIG_TRACING
75 #define TRACE_PRINTKS() VMLINUX_SYMBOL(__start___trace_bprintk_fmt) = .;      \
76                          *(__trace_printk_fmt) /* Trace_printk fmt' pointer */ \
77                          VMLINUX_SYMBOL(__stop___trace_bprintk_fmt) = .;
78 #else
79 #define TRACE_PRINTKS()
80 #endif
81
82 #ifdef CONFIG_FTRACE_SYSCALLS
83 #define TRACE_SYSCALLS() VMLINUX_SYMBOL(__start_syscalls_metadata) = .; \
84                          *(__syscalls_metadata)                         \
85                          VMLINUX_SYMBOL(__stop_syscalls_metadata) = .;
86 #else
87 #define TRACE_SYSCALLS()
88 #endif
89
90 /* .data section */
91 #define DATA_DATA                                                       \
92         *(.data)                                                        \
93         *(.ref.data)                                                    \
94         DEV_KEEP(init.data)                                             \
95         DEV_KEEP(exit.data)                                             \
96         CPU_KEEP(init.data)                                             \
97         CPU_KEEP(exit.data)                                             \
98         MEM_KEEP(init.data)                                             \
99         MEM_KEEP(exit.data)                                             \
100         . = ALIGN(8);                                                   \
101         VMLINUX_SYMBOL(__start___markers) = .;                          \
102         *(__markers)                                                    \
103         VMLINUX_SYMBOL(__stop___markers) = .;                           \
104         . = ALIGN(32);                                                  \
105         VMLINUX_SYMBOL(__start___tracepoints) = .;                      \
106         *(__tracepoints)                                                \
107         VMLINUX_SYMBOL(__stop___tracepoints) = .;                       \
108         /* implement dynamic printk debug */                            \
109         . = ALIGN(8);                                                   \
110         VMLINUX_SYMBOL(__start___verbose) = .;                          \
111         *(__verbose)                                                    \
112         VMLINUX_SYMBOL(__stop___verbose) = .;                           \
113         LIKELY_PROFILE()                                                \
114         BRANCH_PROFILE()                                                \
115         TRACE_PRINTKS()                                                 \
116         FTRACE_EVENTS()                                                 \
117         TRACE_SYSCALLS()
118
119 #define RO_DATA(align)                                                  \
120         . = ALIGN((align));                                             \
121         .rodata           : AT(ADDR(.rodata) - LOAD_OFFSET) {           \
122                 VMLINUX_SYMBOL(__start_rodata) = .;                     \
123                 *(.rodata) *(.rodata.*)                                 \
124                 *(__vermagic)           /* Kernel version magic */      \
125                 *(__markers_strings)    /* Markers: strings */          \
126                 *(__tracepoints_strings)/* Tracepoints: strings */      \
127         }                                                               \
128                                                                         \
129         .rodata1          : AT(ADDR(.rodata1) - LOAD_OFFSET) {          \
130                 *(.rodata1)                                             \
131         }                                                               \
132                                                                         \
133         BUG_TABLE                                                       \
134                                                                         \
135         /* PCI quirks */                                                \
136         .pci_fixup        : AT(ADDR(.pci_fixup) - LOAD_OFFSET) {        \
137                 VMLINUX_SYMBOL(__start_pci_fixups_early) = .;           \
138                 *(.pci_fixup_early)                                     \
139                 VMLINUX_SYMBOL(__end_pci_fixups_early) = .;             \
140                 VMLINUX_SYMBOL(__start_pci_fixups_header) = .;          \
141                 *(.pci_fixup_header)                                    \
142                 VMLINUX_SYMBOL(__end_pci_fixups_header) = .;            \
143                 VMLINUX_SYMBOL(__start_pci_fixups_final) = .;           \
144                 *(.pci_fixup_final)                                     \
145                 VMLINUX_SYMBOL(__end_pci_fixups_final) = .;             \
146                 VMLINUX_SYMBOL(__start_pci_fixups_enable) = .;          \
147                 *(.pci_fixup_enable)                                    \
148                 VMLINUX_SYMBOL(__end_pci_fixups_enable) = .;            \
149                 VMLINUX_SYMBOL(__start_pci_fixups_resume) = .;          \
150                 *(.pci_fixup_resume)                                    \
151                 VMLINUX_SYMBOL(__end_pci_fixups_resume) = .;            \
152                 VMLINUX_SYMBOL(__start_pci_fixups_resume_early) = .;    \
153                 *(.pci_fixup_resume_early)                              \
154                 VMLINUX_SYMBOL(__end_pci_fixups_resume_early) = .;      \
155                 VMLINUX_SYMBOL(__start_pci_fixups_suspend) = .;         \
156                 *(.pci_fixup_suspend)                                   \
157                 VMLINUX_SYMBOL(__end_pci_fixups_suspend) = .;           \
158         }                                                               \
159                                                                         \
160         /* Built-in firmware blobs */                                   \
161         .builtin_fw        : AT(ADDR(.builtin_fw) - LOAD_OFFSET) {      \
162                 VMLINUX_SYMBOL(__start_builtin_fw) = .;                 \
163                 *(.builtin_fw)                                          \
164                 VMLINUX_SYMBOL(__end_builtin_fw) = .;                   \
165         }                                                               \
166                                                                         \
167         /* RapidIO route ops */                                         \
168         .rio_route        : AT(ADDR(.rio_route) - LOAD_OFFSET) {        \
169                 VMLINUX_SYMBOL(__start_rio_route_ops) = .;              \
170                 *(.rio_route_ops)                                       \
171                 VMLINUX_SYMBOL(__end_rio_route_ops) = .;                \
172         }                                                               \
173                                                                         \
174         TRACEDATA                                                       \
175                                                                         \
176         /* Kernel symbol table: Normal symbols */                       \
177         __ksymtab         : AT(ADDR(__ksymtab) - LOAD_OFFSET) {         \
178                 VMLINUX_SYMBOL(__start___ksymtab) = .;                  \
179                 *(__ksymtab)                                            \
180                 VMLINUX_SYMBOL(__stop___ksymtab) = .;                   \
181         }                                                               \
182                                                                         \
183         /* Kernel symbol table: GPL-only symbols */                     \
184         __ksymtab_gpl     : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) {     \
185                 VMLINUX_SYMBOL(__start___ksymtab_gpl) = .;              \
186                 *(__ksymtab_gpl)                                        \
187                 VMLINUX_SYMBOL(__stop___ksymtab_gpl) = .;               \
188         }                                                               \
189                                                                         \
190         /* Kernel symbol table: Normal unused symbols */                \
191         __ksymtab_unused  : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) {  \
192                 VMLINUX_SYMBOL(__start___ksymtab_unused) = .;           \
193                 *(__ksymtab_unused)                                     \
194                 VMLINUX_SYMBOL(__stop___ksymtab_unused) = .;            \
195         }                                                               \
196                                                                         \
197         /* Kernel symbol table: GPL-only unused symbols */              \
198         __ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \
199                 VMLINUX_SYMBOL(__start___ksymtab_unused_gpl) = .;       \
200                 *(__ksymtab_unused_gpl)                                 \
201                 VMLINUX_SYMBOL(__stop___ksymtab_unused_gpl) = .;        \
202         }                                                               \
203                                                                         \
204         /* Kernel symbol table: GPL-future-only symbols */              \
205         __ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \
206                 VMLINUX_SYMBOL(__start___ksymtab_gpl_future) = .;       \
207                 *(__ksymtab_gpl_future)                                 \
208                 VMLINUX_SYMBOL(__stop___ksymtab_gpl_future) = .;        \
209         }                                                               \
210                                                                         \
211         /* Kernel symbol table: Normal symbols */                       \
212         __kcrctab         : AT(ADDR(__kcrctab) - LOAD_OFFSET) {         \
213                 VMLINUX_SYMBOL(__start___kcrctab) = .;                  \
214                 *(__kcrctab)                                            \
215                 VMLINUX_SYMBOL(__stop___kcrctab) = .;                   \
216         }                                                               \
217                                                                         \
218         /* Kernel symbol table: GPL-only symbols */                     \
219         __kcrctab_gpl     : AT(ADDR(__kcrctab_gpl) - LOAD_OFFSET) {     \
220                 VMLINUX_SYMBOL(__start___kcrctab_gpl) = .;              \
221                 *(__kcrctab_gpl)                                        \
222                 VMLINUX_SYMBOL(__stop___kcrctab_gpl) = .;               \
223         }                                                               \
224                                                                         \
225         /* Kernel symbol table: Normal unused symbols */                \
226         __kcrctab_unused  : AT(ADDR(__kcrctab_unused) - LOAD_OFFSET) {  \
227                 VMLINUX_SYMBOL(__start___kcrctab_unused) = .;           \
228                 *(__kcrctab_unused)                                     \
229                 VMLINUX_SYMBOL(__stop___kcrctab_unused) = .;            \
230         }                                                               \
231                                                                         \
232         /* Kernel symbol table: GPL-only unused symbols */              \
233         __kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \
234                 VMLINUX_SYMBOL(__start___kcrctab_unused_gpl) = .;       \
235                 *(__kcrctab_unused_gpl)                                 \
236                 VMLINUX_SYMBOL(__stop___kcrctab_unused_gpl) = .;        \
237         }                                                               \
238                                                                         \
239         /* Kernel symbol table: GPL-future-only symbols */              \
240         __kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \
241                 VMLINUX_SYMBOL(__start___kcrctab_gpl_future) = .;       \
242                 *(__kcrctab_gpl_future)                                 \
243                 VMLINUX_SYMBOL(__stop___kcrctab_gpl_future) = .;        \
244         }                                                               \
245                                                                         \
246         /* Kernel symbol table: strings */                              \
247         __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \
248                 *(__ksymtab_strings)                                    \
249         }                                                               \
250                                                                         \
251         /* __*init sections */                                          \
252         __init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) {         \
253                 *(.ref.rodata)                                          \
254                 MCOUNT_REC()                                            \
255                 DEV_KEEP(init.rodata)                                   \
256                 DEV_KEEP(exit.rodata)                                   \
257                 CPU_KEEP(init.rodata)                                   \
258                 CPU_KEEP(exit.rodata)                                   \
259                 MEM_KEEP(init.rodata)                                   \
260                 MEM_KEEP(exit.rodata)                                   \
261         }                                                               \
262                                                                         \
263         /* Built-in module parameters. */                               \
264         __param : AT(ADDR(__param) - LOAD_OFFSET) {                     \
265                 VMLINUX_SYMBOL(__start___param) = .;                    \
266                 *(__param)                                              \
267                 VMLINUX_SYMBOL(__stop___param) = .;                     \
268                 . = ALIGN((align));                                     \
269                 VMLINUX_SYMBOL(__end_rodata) = .;                       \
270         }                                                               \
271         . = ALIGN((align));
272
273 /* RODATA provided for backward compatibility.
274  * All archs are supposed to use RO_DATA() */
275 #define RODATA RO_DATA(4096)
276
277 #define SECURITY_INIT                                                   \
278         .security_initcall.init : AT(ADDR(.security_initcall.init) - LOAD_OFFSET) { \
279                 VMLINUX_SYMBOL(__security_initcall_start) = .;          \
280                 *(.security_initcall.init)                              \
281                 VMLINUX_SYMBOL(__security_initcall_end) = .;            \
282         }
283
284 /* .text section. Map to function alignment to avoid address changes
285  * during second ld run in second ld pass when generating System.map */
286 #define TEXT_TEXT                                                       \
287                 ALIGN_FUNCTION();                                       \
288                 *(.text.hot)                                            \
289                 *(.text)                                                \
290                 *(.ref.text)                                            \
291         DEV_KEEP(init.text)                                             \
292         DEV_KEEP(exit.text)                                             \
293         CPU_KEEP(init.text)                                             \
294         CPU_KEEP(exit.text)                                             \
295         MEM_KEEP(init.text)                                             \
296         MEM_KEEP(exit.text)                                             \
297                 *(.text.unlikely)
298
299
300 /* sched.text is aling to function alignment to secure we have same
301  * address even at second ld pass when generating System.map */
302 #define SCHED_TEXT                                                      \
303                 ALIGN_FUNCTION();                                       \
304                 VMLINUX_SYMBOL(__sched_text_start) = .;                 \
305                 *(.sched.text)                                          \
306                 VMLINUX_SYMBOL(__sched_text_end) = .;
307
308 /* spinlock.text is aling to function alignment to secure we have same
309  * address even at second ld pass when generating System.map */
310 #define LOCK_TEXT                                                       \
311                 ALIGN_FUNCTION();                                       \
312                 VMLINUX_SYMBOL(__lock_text_start) = .;                  \
313                 *(.spinlock.text)                                       \
314                 VMLINUX_SYMBOL(__lock_text_end) = .;
315
316 #define KPROBES_TEXT                                                    \
317                 ALIGN_FUNCTION();                                       \
318                 VMLINUX_SYMBOL(__kprobes_text_start) = .;               \
319                 *(.kprobes.text)                                        \
320                 VMLINUX_SYMBOL(__kprobes_text_end) = .;
321
322 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
323 #define IRQENTRY_TEXT                                                   \
324                 ALIGN_FUNCTION();                                       \
325                 VMLINUX_SYMBOL(__irqentry_text_start) = .;              \
326                 *(.irqentry.text)                                       \
327                 VMLINUX_SYMBOL(__irqentry_text_end) = .;
328 #else
329 #define IRQENTRY_TEXT
330 #endif
331
332 /* Section used for early init (in .S files) */
333 #define HEAD_TEXT  *(HEAD_TEXT_SECTION)
334
335 /* init and exit section handling */
336 #define INIT_DATA                                                       \
337         *(.init.data)                                                   \
338         DEV_DISCARD(init.data)                                          \
339         DEV_DISCARD(init.rodata)                                        \
340         CPU_DISCARD(init.data)                                          \
341         CPU_DISCARD(init.rodata)                                        \
342         MEM_DISCARD(init.data)                                          \
343         MEM_DISCARD(init.rodata)
344
345 #define INIT_TEXT                                                       \
346         *(.init.text)                                                   \
347         DEV_DISCARD(init.text)                                          \
348         CPU_DISCARD(init.text)                                          \
349         MEM_DISCARD(init.text)
350
351 #define EXIT_DATA                                                       \
352         *(.exit.data)                                                   \
353         DEV_DISCARD(exit.data)                                          \
354         DEV_DISCARD(exit.rodata)                                        \
355         CPU_DISCARD(exit.data)                                          \
356         CPU_DISCARD(exit.rodata)                                        \
357         MEM_DISCARD(exit.data)                                          \
358         MEM_DISCARD(exit.rodata)
359
360 #define EXIT_TEXT                                                       \
361         *(.exit.text)                                                   \
362         DEV_DISCARD(exit.text)                                          \
363         CPU_DISCARD(exit.text)                                          \
364         MEM_DISCARD(exit.text)
365
366                 /* DWARF debug sections.
367                 Symbols in the DWARF debugging sections are relative to
368                 the beginning of the section so we begin them at 0.  */
369 #define DWARF_DEBUG                                                     \
370                 /* DWARF 1 */                                           \
371                 .debug          0 : { *(.debug) }                       \
372                 .line           0 : { *(.line) }                        \
373                 /* GNU DWARF 1 extensions */                            \
374                 .debug_srcinfo  0 : { *(.debug_srcinfo) }               \
375                 .debug_sfnames  0 : { *(.debug_sfnames) }               \
376                 /* DWARF 1.1 and DWARF 2 */                             \
377                 .debug_aranges  0 : { *(.debug_aranges) }               \
378                 .debug_pubnames 0 : { *(.debug_pubnames) }              \
379                 /* DWARF 2 */                                           \
380                 .debug_info     0 : { *(.debug_info                     \
381                                 .gnu.linkonce.wi.*) }                   \
382                 .debug_abbrev   0 : { *(.debug_abbrev) }                \
383                 .debug_line     0 : { *(.debug_line) }                  \
384                 .debug_frame    0 : { *(.debug_frame) }                 \
385                 .debug_str      0 : { *(.debug_str) }                   \
386                 .debug_loc      0 : { *(.debug_loc) }                   \
387                 .debug_macinfo  0 : { *(.debug_macinfo) }               \
388                 /* SGI/MIPS DWARF 2 extensions */                       \
389                 .debug_weaknames 0 : { *(.debug_weaknames) }            \
390                 .debug_funcnames 0 : { *(.debug_funcnames) }            \
391                 .debug_typenames 0 : { *(.debug_typenames) }            \
392                 .debug_varnames  0 : { *(.debug_varnames) }             \
393
394                 /* Stabs debugging sections.  */
395 #define STABS_DEBUG                                                     \
396                 .stab 0 : { *(.stab) }                                  \
397                 .stabstr 0 : { *(.stabstr) }                            \
398                 .stab.excl 0 : { *(.stab.excl) }                        \
399                 .stab.exclstr 0 : { *(.stab.exclstr) }                  \
400                 .stab.index 0 : { *(.stab.index) }                      \
401                 .stab.indexstr 0 : { *(.stab.indexstr) }                \
402                 .comment 0 : { *(.comment) }
403
404 #ifdef CONFIG_GENERIC_BUG
405 #define BUG_TABLE                                                       \
406         . = ALIGN(8);                                                   \
407         __bug_table : AT(ADDR(__bug_table) - LOAD_OFFSET) {             \
408                 VMLINUX_SYMBOL(__start___bug_table) = .;                \
409                 *(__bug_table)                                          \
410                 VMLINUX_SYMBOL(__stop___bug_table) = .;                 \
411         }
412 #else
413 #define BUG_TABLE
414 #endif
415
416 #ifdef CONFIG_PM_TRACE
417 #define TRACEDATA                                                       \
418         . = ALIGN(4);                                                   \
419         .tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) {               \
420                 VMLINUX_SYMBOL(__tracedata_start) = .;                  \
421                 *(.tracedata)                                           \
422                 VMLINUX_SYMBOL(__tracedata_end) = .;                    \
423         }
424 #else
425 #define TRACEDATA
426 #endif
427
428 #define NOTES                                                           \
429         .notes : AT(ADDR(.notes) - LOAD_OFFSET) {                       \
430                 VMLINUX_SYMBOL(__start_notes) = .;                      \
431                 *(.note.*)                                              \
432                 VMLINUX_SYMBOL(__stop_notes) = .;                       \
433         }
434
435 #define INITCALLS                                                       \
436         *(.initcallearly.init)                                          \
437         VMLINUX_SYMBOL(__early_initcall_end) = .;                       \
438         *(.initcall0.init)                                              \
439         *(.initcall0s.init)                                             \
440         *(.initcall1.init)                                              \
441         *(.initcall1s.init)                                             \
442         *(.initcall2.init)                                              \
443         *(.initcall2s.init)                                             \
444         *(.initcall3.init)                                              \
445         *(.initcall3s.init)                                             \
446         *(.initcall4.init)                                              \
447         *(.initcall4s.init)                                             \
448         *(.initcall5.init)                                              \
449         *(.initcall5s.init)                                             \
450         *(.initcallrootfs.init)                                         \
451         *(.initcall6.init)                                              \
452         *(.initcall6s.init)                                             \
453         *(.initcall7.init)                                              \
454         *(.initcall7s.init)
455
456 /**
457  * PERCPU_VADDR - define output section for percpu area
458  * @vaddr: explicit base address (optional)
459  * @phdr: destination PHDR (optional)
460  *
461  * Macro which expands to output section for percpu area.  If @vaddr
462  * is not blank, it specifies explicit base address and all percpu
463  * symbols will be offset from the given address.  If blank, @vaddr
464  * always equals @laddr + LOAD_OFFSET.
465  *
466  * @phdr defines the output PHDR to use if not blank.  Be warned that
467  * output PHDR is sticky.  If @phdr is specified, the next output
468  * section in the linker script will go there too.  @phdr should have
469  * a leading colon.
470  *
471  * Note that this macros defines __per_cpu_load as an absolute symbol.
472  * If there is no need to put the percpu section at a predetermined
473  * address, use PERCPU().
474  */
475 #define PERCPU_VADDR(vaddr, phdr)                                       \
476         VMLINUX_SYMBOL(__per_cpu_load) = .;                             \
477         .data.percpu vaddr : AT(VMLINUX_SYMBOL(__per_cpu_load)          \
478                                 - LOAD_OFFSET) {                        \
479                 VMLINUX_SYMBOL(__per_cpu_start) = .;                    \
480                 *(.data.percpu.first)                                   \
481                 *(.data.percpu.page_aligned)                            \
482                 *(.data.percpu)                                         \
483                 *(.data.percpu.shared_aligned)                          \
484                 VMLINUX_SYMBOL(__per_cpu_end) = .;                      \
485         } phdr                                                          \
486         . = VMLINUX_SYMBOL(__per_cpu_load) + SIZEOF(.data.percpu);
487
488 /**
489  * PERCPU - define output section for percpu area, simple version
490  * @align: required alignment
491  *
492  * Align to @align and outputs output section for percpu area.  This
493  * macro doesn't maniuplate @vaddr or @phdr and __per_cpu_load and
494  * __per_cpu_start will be identical.
495  *
496  * This macro is equivalent to ALIGN(align); PERCPU_VADDR( , ) except
497  * that __per_cpu_load is defined as a relative symbol against
498  * .data.percpu which is required for relocatable x86_32
499  * configuration.
500  */
501 #define PERCPU(align)                                                   \
502         . = ALIGN(align);                                               \
503         .data.percpu    : AT(ADDR(.data.percpu) - LOAD_OFFSET) {        \
504                 VMLINUX_SYMBOL(__per_cpu_load) = .;                     \
505                 VMLINUX_SYMBOL(__per_cpu_start) = .;                    \
506                 *(.data.percpu.first)                                   \
507                 *(.data.percpu.page_aligned)                            \
508                 *(.data.percpu)                                         \
509                 *(.data.percpu.shared_aligned)                          \
510                 VMLINUX_SYMBOL(__per_cpu_end) = .;                      \
511         }