projects / openwrt / openwrt.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
history | raw | HEAD
kernel: split patches folder up into backport, pending and hack folders
[openwrt/openwrt.git] / target / linux / generic / hack-4.9 / 220-gc_sections.patch
1 From e3d8676f5722b7622685581e06e8f53e6138e3ab Mon Sep 17 00:00:00 2001
2 From: Felix Fietkau <nbd@nbd.name>
3 Date: Sat, 15 Jul 2017 23:42:36 +0200
4 Subject: use -ffunction-sections, -fdata-sections and --gc-sections
5
6 In combination with kernel symbol export stripping this significantly reduces
7 the kernel image size. Used on both ARM and MIPS architectures.
8
9 Signed-off-by: Felix Fietkau <nbd@nbd.name>
10 Signed-off-by: Jonas Gorski <jogo@openwrt.org>
11 Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
12 ---
13 Makefile | 10 +++----
14 arch/arm/Kconfig | 1 +
15 arch/arm/boot/compressed/Makefile | 1 +
16 arch/arm/kernel/vmlinux.lds.S | 26 ++++++++--------
17 arch/mips/Kconfig | 1 +
18 arch/mips/kernel/vmlinux.lds.S | 4 +--
19 include/asm-generic/vmlinux.lds.h | 63 ++++++++++++++++++++-------------------
20 7 files changed, 55 insertions(+), 51 deletions(-)
21
22 diff --git a/Makefile b/Makefile
23 index 42435dfa5fc3..66cdf6a59b53 100644
24 --- a/Makefile
25 +++ b/Makefile
26 @@ -410,6 +410,11 @@ KBUILD_AFLAGS_MODULE := -DMODULE
27 KBUILD_CFLAGS_MODULE := -DMODULE
28 KBUILD_LDFLAGS_MODULE = -T $(srctree)/scripts/module-common.lds $(if $(CONFIG_PROFILING),,-s)
29
30 +ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
31 +KBUILD_CFLAGS_KERNEL += $(call cc-option,-ffunction-sections,)
32 +KBUILD_CFLAGS_KERNEL += $(call cc-option,-fdata-sections,)
33 +endif
34 +
35 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
36 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
37 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
38 @@ -631,11 +636,6 @@ include arch/$(SRCARCH)/Makefile
39 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,)
40 KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,)
41
42 -ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
43 -KBUILD_CFLAGS += $(call cc-option,-ffunction-sections,)
44 -KBUILD_CFLAGS += $(call cc-option,-fdata-sections,)
45 -endif
46 -
47 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
48 KBUILD_CFLAGS += -Os $(call cc-disable-warning,maybe-uninitialized,) $(EXTRA_OPTIMIZATION)
49 else
50 diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
51 index b5d529fdffab..7f69418bf02c 100644
52 --- a/arch/arm/Kconfig
53 +++ b/arch/arm/Kconfig
54 @@ -81,6 +81,7 @@ config ARM
55 select HAVE_UID16
56 select HAVE_VIRT_CPU_ACCOUNTING_GEN
57 select IRQ_FORCED_THREADING
58 + select LD_DEAD_CODE_DATA_ELIMINATION
59 select MODULES_USE_ELF_REL
60 select NO_BOOTMEM
61 select OF_EARLY_FLATTREE if OF
62 diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
63 index d50430c40045..6bdeb009a46d 100644
64 --- a/arch/arm/boot/compressed/Makefile
65 +++ b/arch/arm/boot/compressed/Makefile
66 @@ -102,6 +102,7 @@ ifeq ($(CONFIG_FUNCTION_TRACER),y)
67 ORIG_CFLAGS := $(KBUILD_CFLAGS)
68 KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS))
69 endif
70 +KBUILD_CFLAGS_KERNEL := $(patsubst -f%-sections,,$(KBUILD_CFLAGS_KERNEL))
71
72 # -fstack-protector-strong triggers protection checks in this code,
73 # but it is being used too early to link to meaningful stack_chk logic.
74 diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
75 index f7f55df0bf7b..e9d70c92d99f 100644
76 --- a/arch/arm/kernel/vmlinux.lds.S
77 +++ b/arch/arm/kernel/vmlinux.lds.S
78 @@ -17,7 +17,7 @@
79 #define PROC_INFO \
80 . = ALIGN(4); \
81 VMLINUX_SYMBOL(__proc_info_begin) = .; \
82 - *(.proc.info.init) \
83 + KEEP(*(.proc.info.init)) \
84 VMLINUX_SYMBOL(__proc_info_end) = .;
85
86 #define HYPERVISOR_TEXT \
87 @@ -28,11 +28,11 @@
88 #define IDMAP_TEXT \
89 ALIGN_FUNCTION(); \
90 VMLINUX_SYMBOL(__idmap_text_start) = .; \
91 - *(.idmap.text) \
92 + KEEP(*(.idmap.text)) \
93 VMLINUX_SYMBOL(__idmap_text_end) = .; \
94 . = ALIGN(PAGE_SIZE); \
95 VMLINUX_SYMBOL(__hyp_idmap_text_start) = .; \
96 - *(.hyp.idmap.text) \
97 + KEEP(*(.hyp.idmap.text)) \
98 VMLINUX_SYMBOL(__hyp_idmap_text_end) = .;
99
100 #ifdef CONFIG_HOTPLUG_CPU
101 @@ -105,7 +105,7 @@ SECTIONS
102 _stext = .; /* Text and read-only data */
103 IDMAP_TEXT
104 __exception_text_start = .;
105 - *(.exception.text)
106 + KEEP(*(.exception.text))
107 __exception_text_end = .;
108 IRQENTRY_TEXT
109 SOFTIRQENTRY_TEXT
110 @@ -134,7 +134,7 @@ SECTIONS
111 __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
112 __start___ex_table = .;
113 #ifdef CONFIG_MMU
114 - *(__ex_table)
115 + KEEP(*(__ex_table))
116 #endif
117 __stop___ex_table = .;
118 }
119 @@ -146,12 +146,12 @@ SECTIONS
120 . = ALIGN(8);
121 .ARM.unwind_idx : {
122 __start_unwind_idx = .;
123 - *(.ARM.exidx*)
124 + KEEP(*(.ARM.exidx*))
125 __stop_unwind_idx = .;
126 }
127 .ARM.unwind_tab : {
128 __start_unwind_tab = .;
129 - *(.ARM.extab*)
130 + KEEP(*(.ARM.extab*))
131 __stop_unwind_tab = .;
132 }
133 #endif
134 @@ -171,14 +171,14 @@ SECTIONS
135 */
136 __vectors_start = .;
137 .vectors 0xffff0000 : AT(__vectors_start) {
138 - *(.vectors)
139 + KEEP(*(.vectors))
140 }
141 . = __vectors_start + SIZEOF(.vectors);
142 __vectors_end = .;
143
144 __stubs_start = .;
145 .stubs ADDR(.vectors) + 0x1000 : AT(__stubs_start) {
146 - *(.stubs)
147 + KEEP(*(.stubs))
148 }
149 . = __stubs_start + SIZEOF(.stubs);
150 __stubs_end = .;
151 @@ -194,24 +194,24 @@ SECTIONS
152 }
153 .init.arch.info : {
154 __arch_info_begin = .;
155 - *(.arch.info.init)
156 + KEEP(*(.arch.info.init))
157 __arch_info_end = .;
158 }
159 .init.tagtable : {
160 __tagtable_begin = .;
161 - *(.taglist.init)
162 + KEEP(*(.taglist.init))
163 __tagtable_end = .;
164 }
165 #ifdef CONFIG_SMP_ON_UP
166 .init.smpalt : {
167 __smpalt_begin = .;
168 - *(.alt.smp.init)
169 + KEEP(*(.alt.smp.init))
170 __smpalt_end = .;
171 }
172 #endif
173 .init.pv_table : {
174 __pv_table_begin = .;
175 - *(.pv_table)
176 + KEEP(*(.pv_table))
177 __pv_table_end = .;
178 }
179 .init.data : {
180 diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
181 index 3a97487b8b81..05e7bfeab2f9 100644
182 --- a/arch/mips/Kconfig
183 +++ b/arch/mips/Kconfig
184 @@ -55,6 +55,7 @@ config MIPS
185 select CLONE_BACKWARDS
186 select HAVE_DEBUG_STACKOVERFLOW
187 select HAVE_CC_STACKPROTECTOR
188 + select LD_DEAD_CODE_DATA_ELIMINATION
189 select CPU_PM if CPU_IDLE
190 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
191 select ARCH_BINFMT_ELF_STATE
192 diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S
193 index d5de67591735..de5f682b5597 100644
194 --- a/arch/mips/kernel/vmlinux.lds.S
195 +++ b/arch/mips/kernel/vmlinux.lds.S
196 @@ -71,7 +71,7 @@ SECTIONS
197 /* Exception table for data bus errors */
198 __dbe_table : {
199 __start___dbe_table = .;
200 - *(__dbe_table)
201 + KEEP(*(__dbe_table))
202 __stop___dbe_table = .;
203 }
204
205 @@ -121,7 +121,7 @@ SECTIONS
206 . = ALIGN(4);
207 .mips.machines.init : AT(ADDR(.mips.machines.init) - LOAD_OFFSET) {
208 __mips_machines_start = .;
209 - *(.mips.machines.init)
210 + KEEP(*(.mips.machines.init))
211 __mips_machines_end = .;
212 }
213
214 diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
215 index 31e1d639abed..83784d9492b1 100644
216 --- a/include/asm-generic/vmlinux.lds.h
217 +++ b/include/asm-generic/vmlinux.lds.h
218 @@ -114,7 +114,7 @@
219 #ifdef CONFIG_KPROBES
220 #define KPROBE_BLACKLIST() . = ALIGN(8); \
221 VMLINUX_SYMBOL(__start_kprobe_blacklist) = .; \
222 - *(_kprobe_blacklist) \
223 + KEEP(*(_kprobe_blacklist)) \
224 VMLINUX_SYMBOL(__stop_kprobe_blacklist) = .;
225 #else
226 #define KPROBE_BLACKLIST()
227 @@ -123,10 +123,10 @@
228 #ifdef CONFIG_EVENT_TRACING
229 #define FTRACE_EVENTS() . = ALIGN(8); \
230 VMLINUX_SYMBOL(__start_ftrace_events) = .; \
231 - *(_ftrace_events) \
232 + KEEP(*(_ftrace_events)) \
233 VMLINUX_SYMBOL(__stop_ftrace_events) = .; \
234 VMLINUX_SYMBOL(__start_ftrace_enum_maps) = .; \
235 - *(_ftrace_enum_map) \
236 + KEEP(*(_ftrace_enum_map)) \
237 VMLINUX_SYMBOL(__stop_ftrace_enum_maps) = .;
238 #else
239 #define FTRACE_EVENTS()
240 @@ -147,7 +147,7 @@
241 #ifdef CONFIG_FTRACE_SYSCALLS
242 #define TRACE_SYSCALLS() . = ALIGN(8); \
243 VMLINUX_SYMBOL(__start_syscalls_metadata) = .; \
244 - *(__syscalls_metadata) \
245 + KEEP(*(__syscalls_metadata)) \
246 VMLINUX_SYMBOL(__stop_syscalls_metadata) = .;
247 #else
248 #define TRACE_SYSCALLS()
249 @@ -156,7 +156,7 @@
250 #ifdef CONFIG_SERIAL_EARLYCON
251 #define EARLYCON_TABLE() STRUCT_ALIGN(); \
252 VMLINUX_SYMBOL(__earlycon_table) = .; \
253 - *(__earlycon_table) \
254 + KEEP(*(__earlycon_table)) \
255 VMLINUX_SYMBOL(__earlycon_table_end) = .;
256 #else
257 #define EARLYCON_TABLE()
258 @@ -169,8 +169,8 @@
259 #define _OF_TABLE_1(name) \
260 . = ALIGN(8); \
261 VMLINUX_SYMBOL(__##name##_of_table) = .; \
262 - *(__##name##_of_table) \
263 - *(__##name##_of_table_end)
264 + KEEP(*(__##name##_of_table)) \
265 + KEEP(*(__##name##_of_table_end))
266
267 #define CLKSRC_OF_TABLES() OF_TABLE(CONFIG_CLKSRC_OF, clksrc)
268 #define IRQCHIP_OF_MATCH_TABLE() OF_TABLE(CONFIG_IRQCHIP, irqchip)
269 @@ -193,7 +193,7 @@
270 #define KERNEL_DTB() \
271 STRUCT_ALIGN(); \
272 VMLINUX_SYMBOL(__dtb_start) = .; \
273 - *(.dtb.init.rodata) \
274 + KEEP(*(.dtb.init.rodata)) \
275 VMLINUX_SYMBOL(__dtb_end) = .;
276
277 /*
278 @@ -214,16 +214,17 @@
279 /* implement dynamic printk debug */ \
280 . = ALIGN(8); \
281 VMLINUX_SYMBOL(__start___jump_table) = .; \
282 - *(__jump_table) \
283 + KEEP(*(__jump_table)) \
284 VMLINUX_SYMBOL(__stop___jump_table) = .; \
285 . = ALIGN(8); \
286 VMLINUX_SYMBOL(__start___verbose) = .; \
287 - *(__verbose) \
288 + KEEP(*(__verbose)) \
289 VMLINUX_SYMBOL(__stop___verbose) = .; \
290 LIKELY_PROFILE() \
291 BRANCH_PROFILE() \
292 TRACE_PRINTKS() \
293 - TRACEPOINT_STR()
294 + TRACEPOINT_STR() \
295 + *(.data.[a-zA-Z_]*)
296
297 /*
298 * Data section helpers
299 @@ -291,35 +292,35 @@
300 /* PCI quirks */ \
301 .pci_fixup : AT(ADDR(.pci_fixup) - LOAD_OFFSET) { \
302 VMLINUX_SYMBOL(__start_pci_fixups_early) = .; \
303 - *(.pci_fixup_early) \
304 + KEEP(*(.pci_fixup_early)) \
305 VMLINUX_SYMBOL(__end_pci_fixups_early) = .; \
306 VMLINUX_SYMBOL(__start_pci_fixups_header) = .; \
307 - *(.pci_fixup_header) \
308 + KEEP(*(.pci_fixup_header)) \
309 VMLINUX_SYMBOL(__end_pci_fixups_header) = .; \
310 VMLINUX_SYMBOL(__start_pci_fixups_final) = .; \
311 - *(.pci_fixup_final) \
312 + KEEP(*(.pci_fixup_final)) \
313 VMLINUX_SYMBOL(__end_pci_fixups_final) = .; \
314 VMLINUX_SYMBOL(__start_pci_fixups_enable) = .; \
315 - *(.pci_fixup_enable) \
316 + KEEP(*(.pci_fixup_enable)) \
317 VMLINUX_SYMBOL(__end_pci_fixups_enable) = .; \
318 VMLINUX_SYMBOL(__start_pci_fixups_resume) = .; \
319 - *(.pci_fixup_resume) \
320 + KEEP(*(.pci_fixup_resume)) \
321 VMLINUX_SYMBOL(__end_pci_fixups_resume) = .; \
322 VMLINUX_SYMBOL(__start_pci_fixups_resume_early) = .; \
323 - *(.pci_fixup_resume_early) \
324 + KEEP(*(.pci_fixup_resume_early)) \
325 VMLINUX_SYMBOL(__end_pci_fixups_resume_early) = .; \
326 VMLINUX_SYMBOL(__start_pci_fixups_suspend) = .; \
327 - *(.pci_fixup_suspend) \
328 + KEEP(*(.pci_fixup_suspend)) \
329 VMLINUX_SYMBOL(__end_pci_fixups_suspend) = .; \
330 VMLINUX_SYMBOL(__start_pci_fixups_suspend_late) = .; \
331 - *(.pci_fixup_suspend_late) \
332 + KEEP(*(.pci_fixup_suspend_late)) \
333 VMLINUX_SYMBOL(__end_pci_fixups_suspend_late) = .; \
334 } \
335 \
336 /* Built-in firmware blobs */ \
337 .builtin_fw : AT(ADDR(.builtin_fw) - LOAD_OFFSET) { \
338 VMLINUX_SYMBOL(__start_builtin_fw) = .; \
339 - *(.builtin_fw) \
340 + KEEP(*(.builtin_fw)) \
341 VMLINUX_SYMBOL(__end_builtin_fw) = .; \
342 } \
343 \
344 @@ -397,7 +398,7 @@
345 \
346 /* Kernel symbol table: strings */ \
347 __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \
348 - KEEP(*(__ksymtab_strings)) \
349 + *(__ksymtab_strings) \
350 } \
351 \
352 /* __*init sections */ \
353 @@ -410,14 +411,14 @@
354 /* Built-in module parameters. */ \
355 __param : AT(ADDR(__param) - LOAD_OFFSET) { \
356 VMLINUX_SYMBOL(__start___param) = .; \
357 - *(__param) \
358 + KEEP(*(__param)) \
359 VMLINUX_SYMBOL(__stop___param) = .; \
360 } \
361 \
362 /* Built-in module versions. */ \
363 __modver : AT(ADDR(__modver) - LOAD_OFFSET) { \
364 VMLINUX_SYMBOL(__start___modver) = .; \
365 - *(__modver) \
366 + KEEP(*(__modver)) \
367 VMLINUX_SYMBOL(__stop___modver) = .; \
368 . = ALIGN((align)); \
369 VMLINUX_SYMBOL(__end_rodata) = .; \
370 @@ -482,7 +483,7 @@
371 #define ENTRY_TEXT \
372 ALIGN_FUNCTION(); \
373 VMLINUX_SYMBOL(__entry_text_start) = .; \
374 - *(.entry.text) \
375 + KEEP(*(.entry.text)) \
376 VMLINUX_SYMBOL(__entry_text_end) = .;
377
378 #if defined(CONFIG_FUNCTION_GRAPH_TRACER) || defined(CONFIG_KASAN)
379 @@ -520,7 +521,7 @@
380 . = ALIGN(align); \
381 __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { \
382 VMLINUX_SYMBOL(__start___ex_table) = .; \
383 - *(__ex_table) \
384 + KEEP(*(__ex_table)) \
385 VMLINUX_SYMBOL(__stop___ex_table) = .; \
386 }
387
388 @@ -536,9 +537,9 @@
389 #ifdef CONFIG_CONSTRUCTORS
390 #define KERNEL_CTORS() . = ALIGN(8); \
391 VMLINUX_SYMBOL(__ctors_start) = .; \
392 - *(.ctors) \
393 + KEEP(*(.ctors)) \
394 *(SORT(.init_array.*)) \
395 - *(.init_array) \
396 + KEEP(*(.init_array)) \
397 VMLINUX_SYMBOL(__ctors_end) = .;
398 #else
399 #define KERNEL_CTORS()
400 @@ -595,7 +596,7 @@
401 #define SBSS(sbss_align) \
402 . = ALIGN(sbss_align); \
403 .sbss : AT(ADDR(.sbss) - LOAD_OFFSET) { \
404 - *(.sbss) \
405 + *(.sbss .sbss.*) \
406 *(.scommon) \
407 }
408
409 @@ -662,7 +663,7 @@
410 . = ALIGN(8); \
411 __bug_table : AT(ADDR(__bug_table) - LOAD_OFFSET) { \
412 VMLINUX_SYMBOL(__start___bug_table) = .; \
413 - *(__bug_table) \
414 + KEEP(*(__bug_table)) \
415 VMLINUX_SYMBOL(__stop___bug_table) = .; \
416 }
417 #else
418 @@ -674,7 +675,7 @@
419 . = ALIGN(4); \
420 .tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) { \
421 VMLINUX_SYMBOL(__tracedata_start) = .; \
422 - *(.tracedata) \
423 + KEEP(*(.tracedata)) \
424 VMLINUX_SYMBOL(__tracedata_end) = .; \
425 }
426 #else
427 @@ -691,7 +692,7 @@
428 #define INIT_SETUP(initsetup_align) \
429 . = ALIGN(initsetup_align); \
430 VMLINUX_SYMBOL(__setup_start) = .; \
431 - *(.init.setup) \
432 + KEEP(*(.init.setup)) \
433 VMLINUX_SYMBOL(__setup_end) = .;
434
435 #define INIT_CALLS_LEVEL(level) \
436 --
437 2.11.0
438
OpenWrt Source Repository