From 0043ecea2399ffc8bfd99ed9dbbe766e7c79293c Mon Sep 17 00:00:00 2001 From: Rong Xu Date: Sat, 2 Nov 2024 10:51:10 -0700 Subject: vmlinux.lds.h: Adjust symbol ordering in text output section MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When the -ffunction-sections compiler option is enabled, each function is placed in a separate section named .text.function_name rather than putting all functions in a single .text section. However, using -function-sections can cause problems with the linker script. The comments included in include/asm-generic/vmlinux.lds.h note these issues.: “TEXT_MAIN here will match .text.fixup and .text.unlikely if dead code elimination is enabled, so these sections should be converted to use ".." first.” It is unclear whether there is a straightforward method for converting a suffix to "..". This patch modifies the order of subsections within the text output section. Specifically, it changes current order: .text.hot, .text, .text_unlikely, .text.unknown, .text.asan to the new order: .text.asan, .text.unknown, .text_unlikely, .text.hot, .text Here is the rationale behind the new layout: The majority of the code resides in three sections: .text.hot, .text, and .text.unlikely, with .text.unknown containing a negligible amount. .text.asan is only generated in ASAN builds. The primary goal is to group code segments based on their execution frequency (hotness). First, we want to place .text.hot adjacent to .text. Since we cannot put .text.hot after .text (Due to constraints with -ffunction-sections, placing .text.hot after .text is problematic), we need to put .text.hot before .text. Then it comes to .text.unlikely, we cannot put it after .text (same -ffunction-sections issue) . Therefore, we position .text.unlikely before .text.hot. .text.unknown and .tex.asan follow the same logic. This revised ordering effectively reverses the original arrangement (for .text.unlikely, .text.unknown, and .tex.asan), maintaining a similar level of affinity between sections. It also places .text.hot section at the beginning of a page to better utilize the TLB entry. Note that the limitation arises because the linker script employs glob patterns instead of regular expressions for string matching. While there is a method to maintain the current order using complex patterns, this significantly complicates the pattern and increases the likelihood of errors. This patch also changes vmlinux.lds.S for the sparc64 architecture to accommodate specific symbol placement requirements. Co-developed-by: Han Shen Signed-off-by: Han Shen Signed-off-by: Rong Xu Suggested-by: Sriraman Tallam Suggested-by: Krzysztof Pszeniczny Tested-by: Yonghong Song Tested-by: Yabin Cui Tested-by: Nathan Chancellor Reviewed-by: Kees Cook Signed-off-by: Masahiro Yamada --- include/asm-generic/vmlinux.lds.h | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index eeadbaeccf88..fd901951549c 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -553,19 +553,24 @@ * .text section. Map to function alignment to avoid address changes * during second ld run in second ld pass when generating System.map * - * TEXT_MAIN here will match .text.fixup and .text.unlikely if dead - * code elimination is enabled, so these sections should be converted - * to use ".." first. + * TEXT_MAIN here will match symbols with a fixed pattern (for example, + * .text.hot or .text.unlikely) if dead code elimination or + * function-section is enabled. Match these symbols first before + * TEXT_MAIN to ensure they are grouped together. + * + * Also placing .text.hot section at the beginning of a page, this + * would help the TLB performance. */ #define TEXT_TEXT \ ALIGN_FUNCTION(); \ + *(.text.asan.* .text.tsan.*) \ + *(.text.unknown .text.unknown.*) \ + *(.text.unlikely .text.unlikely.*) \ + . = ALIGN(PAGE_SIZE); \ *(.text.hot .text.hot.*) \ *(TEXT_MAIN .text.fixup) \ - *(.text.unlikely .text.unlikely.*) \ - *(.text.unknown .text.unknown.*) \ NOINSTR_TEXT \ - *(.ref.text) \ - *(.text.asan.* .text.tsan.*) + *(.ref.text) /* sched.text is aling to function alignment to secure we have same -- cgit v1.2.3 From db0b2991ae1aac5ca985ec6fd8ff9bd9b2126c9b Mon Sep 17 00:00:00 2001 From: Rong Xu Date: Sat, 2 Nov 2024 10:51:11 -0700 Subject: vmlinux.lds.h: Add markers for text_unlikely and text_hot sections Add markers like __hot_text_start, __hot_text_end, __unlikely_text_start, and __unlikely_text_end which will be included in System.map. These markers indicate how the compiler groups functions, providing valuable information to developers about the layout and optimization of the code. Co-developed-by: Han Shen Signed-off-by: Han Shen Signed-off-by: Rong Xu Suggested-by: Sriraman Tallam Tested-by: Yonghong Song Tested-by: Yabin Cui Tested-by: Nathan Chancellor Reviewed-by: Kees Cook Signed-off-by: Masahiro Yamada --- include/asm-generic/vmlinux.lds.h | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index fd901951549c..e02973f3b418 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -549,6 +549,16 @@ __cpuidle_text_end = .; \ __noinstr_text_end = .; +#define TEXT_UNLIKELY \ + __unlikely_text_start = .; \ + *(.text.unlikely .text.unlikely.*) \ + __unlikely_text_end = .; + +#define TEXT_HOT \ + __hot_text_start = .; \ + *(.text.hot .text.hot.*) \ + __hot_text_end = .; + /* * .text section. Map to function alignment to avoid address changes * during second ld run in second ld pass when generating System.map @@ -565,9 +575,9 @@ ALIGN_FUNCTION(); \ *(.text.asan.* .text.tsan.*) \ *(.text.unknown .text.unknown.*) \ - *(.text.unlikely .text.unlikely.*) \ + TEXT_UNLIKELY \ . = ALIGN(PAGE_SIZE); \ - *(.text.hot .text.hot.*) \ + TEXT_HOT \ *(TEXT_MAIN .text.fixup) \ NOINSTR_TEXT \ *(.ref.text) -- cgit v1.2.3 From 0847420f5e499a7ab518942fff71482179290163 Mon Sep 17 00:00:00 2001 From: Rong Xu Date: Sat, 2 Nov 2024 10:51:12 -0700 Subject: AutoFDO: Enable -ffunction-sections for the AutoFDO build Enable -ffunction-sections by default for the AutoFDO build. With -ffunction-sections, the compiler places each function in its own section named .text.function_name instead of placing all functions in the .text section. In the AutoFDO build, this allows the linker to utilize profile information to reorganize functions for improved utilization of iCache and iTLB. Co-developed-by: Han Shen Signed-off-by: Han Shen Signed-off-by: Rong Xu Suggested-by: Sriraman Tallam Tested-by: Yonghong Song Tested-by: Yabin Cui Tested-by: Nathan Chancellor Reviewed-by: Kees Cook Signed-off-by: Masahiro Yamada --- include/asm-generic/vmlinux.lds.h | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index e02973f3b418..bd64fdedabd2 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -95,18 +95,25 @@ * With LTO_CLANG, the linker also splits sections by default, so we need * these macros to combine the sections during the final link. * + * With AUTOFDO_CLANG, by default, the linker splits text sections and + * regroups functions into subsections. + * * RODATA_MAIN is not used because existing code already defines .rodata.x * sections to be brought in with rodata. */ -#if defined(CONFIG_LD_DEAD_CODE_DATA_ELIMINATION) || defined(CONFIG_LTO_CLANG) +#if defined(CONFIG_LD_DEAD_CODE_DATA_ELIMINATION) || defined(CONFIG_LTO_CLANG) || \ +defined(CONFIG_AUTOFDO_CLANG) #define TEXT_MAIN .text .text.[0-9a-zA-Z_]* +#else +#define TEXT_MAIN .text +#endif +#if defined(CONFIG_LD_DEAD_CODE_DATA_ELIMINATION) || defined(CONFIG_LTO_CLANG) #define DATA_MAIN .data .data.[0-9a-zA-Z_]* .data..L* .data..compoundliteral* .data.$__unnamed_* .data.$L* #define SDATA_MAIN .sdata .sdata.[0-9a-zA-Z_]* #define RODATA_MAIN .rodata .rodata.[0-9a-zA-Z_]* .rodata..L* #define BSS_MAIN .bss .bss.[0-9a-zA-Z_]* .bss..L* .bss..compoundliteral* #define SBSS_MAIN .sbss .sbss.[0-9a-zA-Z_]* #else -#define TEXT_MAIN .text #define DATA_MAIN .data #define SDATA_MAIN .sdata #define RODATA_MAIN .rodata -- cgit v1.2.3 From 2fd65f7afd5a73b685a1651cb651ade120b53e15 Mon Sep 17 00:00:00 2001 From: Rong Xu Date: Sat, 2 Nov 2024 10:51:13 -0700 Subject: AutoFDO: Enable machine function split optimization for AutoFDO Enable the machine function split optimization for AutoFDO in Clang. Machine function split (MFS) is a pass in the Clang compiler that splits a function into hot and cold parts. The linker groups all cold blocks across functions together. This decreases hot code fragmentation and improves iCache and iTLB utilization. MFS requires a profile so this is enabled only for the AutoFDO builds. Co-developed-by: Han Shen Signed-off-by: Han Shen Signed-off-by: Rong Xu Suggested-by: Sriraman Tallam Suggested-by: Krzysztof Pszeniczny Tested-by: Yonghong Song Tested-by: Yabin Cui Tested-by: Nathan Chancellor Reviewed-by: Kees Cook Signed-off-by: Masahiro Yamada --- include/asm-generic/vmlinux.lds.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index bd64fdedabd2..8a0bb3946cf0 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -556,6 +556,11 @@ defined(CONFIG_AUTOFDO_CLANG) __cpuidle_text_end = .; \ __noinstr_text_end = .; +#define TEXT_SPLIT \ + __split_text_start = .; \ + *(.text.split .text.split.[0-9a-zA-Z_]*) \ + __split_text_end = .; + #define TEXT_UNLIKELY \ __unlikely_text_start = .; \ *(.text.unlikely .text.unlikely.*) \ @@ -582,6 +587,7 @@ defined(CONFIG_AUTOFDO_CLANG) ALIGN_FUNCTION(); \ *(.text.asan.* .text.tsan.*) \ *(.text.unknown .text.unknown.*) \ + TEXT_SPLIT \ TEXT_UNLIKELY \ . = ALIGN(PAGE_SIZE); \ TEXT_HOT \ @@ -589,7 +595,6 @@ defined(CONFIG_AUTOFDO_CLANG) NOINSTR_TEXT \ *(.ref.text) - /* sched.text is aling to function alignment to secure we have same * address even at second ld pass when generating System.map */ #define SCHED_TEXT \ -- cgit v1.2.3 From d5dc95836147f2e25b134c0ca3a0bc1a5867ea29 Mon Sep 17 00:00:00 2001 From: Rong Xu Date: Sat, 2 Nov 2024 10:51:14 -0700 Subject: kbuild: Add Propeller configuration for kernel build MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add the build support for using Clang's Propeller optimizer. Like AutoFDO, Propeller uses hardware sampling to gather information about the frequency of execution of different code paths within a binary. This information is then used to guide the compiler's optimization decisions, resulting in a more efficient binary. The support requires a Clang compiler LLVM 19 or later, and the create_llvm_prof tool (https://github.com/google/autofdo/releases/tag/v0.30.1). This commit is limited to x86 platforms that support PMU features like LBR on Intel machines and AMD Zen3 BRS. Here is an example workflow for building an AutoFDO+Propeller optimized kernel: 1) Build the kernel on the host machine, with AutoFDO and Propeller build config CONFIG_AUTOFDO_CLANG=y CONFIG_PROPELLER_CLANG=y then $ make LLVM=1 CLANG_AUTOFDO_PROFILE= “” is the profile collected when doing a non-Propeller AutoFDO build. This step builds a kernel that has the same optimization level as AutoFDO, plus a metadata section that records basic block information. This kernel image runs as fast as an AutoFDO optimized kernel. 2) Install the kernel on test/production machines. 3) Run the load tests. The '-c' option in perf specifies the sample event period. We suggest using a suitable prime number, like 500009, for this purpose. For Intel platforms: $ perf record -e BR_INST_RETIRED.NEAR_TAKEN:k -a -N -b -c \ -o -- For AMD platforms: The supported system are: Zen3 with BRS, or Zen4 with amd_lbr_v2 # To see if Zen3 support LBR: $ cat proc/cpuinfo | grep " brs" # To see if Zen4 support LBR: $ cat proc/cpuinfo | grep amd_lbr_v2 # If the result is yes, then collect the profile using: $ perf record --pfm-events RETIRED_TAKEN_BRANCH_INSTRUCTIONS:k -a \ -N -b -c -o -- 4) (Optional) Download the raw perf file to the host machine. 5) Generate Propeller profile: $ create_llvm_prof --binary= --profile= \ --format=propeller --propeller_output_module_name \ --out=_cc_profile.txt \ --propeller_symorder=_ld_profile.txt “create_llvm_prof” is the profile conversion tool, and a prebuilt binary for linux can be found on https://github.com/google/autofdo/releases/tag/v0.30.1 (can also build from source). "" can be something like "/home/user/dir/any_string". This command generates a pair of Propeller profiles: "_cc_profile.txt" and "_ld_profile.txt". 6) Rebuild the kernel using the AutoFDO and Propeller profile files. CONFIG_AUTOFDO_CLANG=y CONFIG_PROPELLER_CLANG=y and $ make LLVM=1 CLANG_AUTOFDO_PROFILE= \ CLANG_PROPELLER_PROFILE_PREFIX= Co-developed-by: Han Shen Signed-off-by: Han Shen Signed-off-by: Rong Xu Suggested-by: Sriraman Tallam Suggested-by: Krzysztof Pszeniczny Suggested-by: Nick Desaulniers Suggested-by: Stephane Eranian Tested-by: Yonghong Song Tested-by: Nathan Chancellor Reviewed-by: Kees Cook Signed-off-by: Masahiro Yamada --- include/asm-generic/vmlinux.lds.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 8a0bb3946cf0..c995474e4c64 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -95,14 +95,14 @@ * With LTO_CLANG, the linker also splits sections by default, so we need * these macros to combine the sections during the final link. * - * With AUTOFDO_CLANG, by default, the linker splits text sections and - * regroups functions into subsections. + * With AUTOFDO_CLANG and PROPELLER_CLANG, by default, the linker splits + * text sections and regroups functions into subsections. * * RODATA_MAIN is not used because existing code already defines .rodata.x * sections to be brought in with rodata. */ #if defined(CONFIG_LD_DEAD_CODE_DATA_ELIMINATION) || defined(CONFIG_LTO_CLANG) || \ -defined(CONFIG_AUTOFDO_CLANG) +defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG) #define TEXT_MAIN .text .text.[0-9a-zA-Z_]* #else #define TEXT_MAIN .text -- cgit v1.2.3 From bb43a59944f45e89aa158740b8a16ba8f0b0fa2b Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 7 Nov 2024 01:14:40 +0900 Subject: Rename .data.unlikely to .data..unlikely Commit 7ccaba5314ca ("consolidate WARN_...ONCE() static variables") was intended to collect all .data.unlikely sections into one chunk. However, this has not worked when CONFIG_LD_DEAD_CODE_DATA_ELIMINATION or CONFIG_LTO_CLANG is enabled, because .data.unlikely matches the .data.[0-9a-zA-Z_]* pattern in the DATA_MAIN macro. Commit cb87481ee89d ("kbuild: linker script do not match C names unless LD_DEAD_CODE_DATA_ELIMINATION is configured") was introduced to suppress the issue for the default CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=n case, providing a minimal fix for stable backporting. We were aware this did not address the issue for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y. The plan was to apply correct fixes and then revert cb87481ee89d. [1] Seven years have passed since then, yet the #ifdef workaround remains in place. Using a ".." separator in the section name fixes the issue for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION and CONFIG_LTO_CLANG. [1]: https://lore.kernel.org/linux-kbuild/CAK7LNASck6BfdLnESxXUeECYL26yUDm0cwRZuM4gmaWUkxjL5g@mail.gmail.com/ Fixes: cb87481ee89d ("kbuild: linker script do not match C names unless LD_DEAD_CODE_DATA_ELIMINATION is configured") Signed-off-by: Masahiro Yamada --- include/asm-generic/vmlinux.lds.h | 2 +- include/linux/rcupdate.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index c995474e4c64..3c9dc1fd094d 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -357,7 +357,7 @@ defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG) *(.data..decrypted) \ *(.ref.data) \ *(.data..shared_aligned) /* percpu related */ \ - *(.data.unlikely) \ + *(.data..unlikely) \ __start_once = .; \ *(.data.once) \ __end_once = .; \ diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 58d84c59f3dd..48e5c03df1dd 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -401,7 +401,7 @@ static inline int debug_lockdep_rcu_enabled(void) */ #define RCU_LOCKDEP_WARN(c, s) \ do { \ - static bool __section(".data.unlikely") __warned; \ + static bool __section(".data..unlikely") __warned; \ if (debug_lockdep_rcu_enabled() && (c) && \ debug_lockdep_rcu_enabled() && !__warned) { \ __warned = true; \ -- cgit v1.2.3 From dbefa1f31a91670c9e7dac9b559625336206466f Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 7 Nov 2024 01:14:41 +0900 Subject: Rename .data.once to .data..once to fix resetting WARN*_ONCE Commit b1fca27d384e ("kernel debug: support resetting WARN*_ONCE") added support for clearing the state of once warnings. However, it is not functional when CONFIG_LD_DEAD_CODE_DATA_ELIMINATION or CONFIG_LTO_CLANG is enabled, because .data.once matches the .data.[0-9a-zA-Z_]* pattern in the DATA_MAIN macro. Commit cb87481ee89d ("kbuild: linker script do not match C names unless LD_DEAD_CODE_DATA_ELIMINATION is configured") was introduced to suppress the issue for the default CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=n case, providing a minimal fix for stable backporting. We were aware this did not address the issue for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y. The plan was to apply correct fixes and then revert cb87481ee89d. [1] Seven years have passed since then, yet the #ifdef workaround remains in place. Meanwhile, commit b1fca27d384e introduced the .data.once section, and commit dc5723b02e52 ("kbuild: add support for Clang LTO") extended the #ifdef. Using a ".." separator in the section name fixes the issue for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION and CONFIG_LTO_CLANG. [1]: https://lore.kernel.org/linux-kbuild/CAK7LNASck6BfdLnESxXUeECYL26yUDm0cwRZuM4gmaWUkxjL5g@mail.gmail.com/ Fixes: b1fca27d384e ("kernel debug: support resetting WARN*_ONCE") Fixes: dc5723b02e52 ("kbuild: add support for Clang LTO") Signed-off-by: Masahiro Yamada --- include/asm-generic/vmlinux.lds.h | 2 +- include/linux/mmdebug.h | 6 +++--- include/linux/once.h | 4 ++-- include/linux/once_lite.h | 2 +- include/net/net_debug.h | 2 +- 5 files changed, 8 insertions(+), 8 deletions(-) (limited to 'include') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 3c9dc1fd094d..54504013c749 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -359,7 +359,7 @@ defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG) *(.data..shared_aligned) /* percpu related */ \ *(.data..unlikely) \ __start_once = .; \ - *(.data.once) \ + *(.data..once) \ __end_once = .; \ STRUCT_ALIGN(); \ *(__tracepoints) \ diff --git a/include/linux/mmdebug.h b/include/linux/mmdebug.h index 39a7714605a7..d7cb1e5ecbda 100644 --- a/include/linux/mmdebug.h +++ b/include/linux/mmdebug.h @@ -46,7 +46,7 @@ void vma_iter_dump_tree(const struct vma_iterator *vmi); } \ } while (0) #define VM_WARN_ON_ONCE_PAGE(cond, page) ({ \ - static bool __section(".data.once") __warned; \ + static bool __section(".data..once") __warned; \ int __ret_warn_once = !!(cond); \ \ if (unlikely(__ret_warn_once && !__warned)) { \ @@ -66,7 +66,7 @@ void vma_iter_dump_tree(const struct vma_iterator *vmi); unlikely(__ret_warn); \ }) #define VM_WARN_ON_ONCE_FOLIO(cond, folio) ({ \ - static bool __section(".data.once") __warned; \ + static bool __section(".data..once") __warned; \ int __ret_warn_once = !!(cond); \ \ if (unlikely(__ret_warn_once && !__warned)) { \ @@ -77,7 +77,7 @@ void vma_iter_dump_tree(const struct vma_iterator *vmi); unlikely(__ret_warn_once); \ }) #define VM_WARN_ON_ONCE_MM(cond, mm) ({ \ - static bool __section(".data.once") __warned; \ + static bool __section(".data..once") __warned; \ int __ret_warn_once = !!(cond); \ \ if (unlikely(__ret_warn_once && !__warned)) { \ diff --git a/include/linux/once.h b/include/linux/once.h index bc714d414448..30346fcdc799 100644 --- a/include/linux/once.h +++ b/include/linux/once.h @@ -46,7 +46,7 @@ void __do_once_sleepable_done(bool *done, struct static_key_true *once_key, #define DO_ONCE(func, ...) \ ({ \ bool ___ret = false; \ - static bool __section(".data.once") ___done = false; \ + static bool __section(".data..once") ___done = false; \ static DEFINE_STATIC_KEY_TRUE(___once_key); \ if (static_branch_unlikely(&___once_key)) { \ unsigned long ___flags; \ @@ -64,7 +64,7 @@ void __do_once_sleepable_done(bool *done, struct static_key_true *once_key, #define DO_ONCE_SLEEPABLE(func, ...) \ ({ \ bool ___ret = false; \ - static bool __section(".data.once") ___done = false; \ + static bool __section(".data..once") ___done = false; \ static DEFINE_STATIC_KEY_TRUE(___once_key); \ if (static_branch_unlikely(&___once_key)) { \ ___ret = __do_once_sleepable_start(&___done); \ diff --git a/include/linux/once_lite.h b/include/linux/once_lite.h index b7bce4983638..27de7bc32a06 100644 --- a/include/linux/once_lite.h +++ b/include/linux/once_lite.h @@ -12,7 +12,7 @@ #define __ONCE_LITE_IF(condition) \ ({ \ - static bool __section(".data.once") __already_done; \ + static bool __section(".data..once") __already_done; \ bool __ret_cond = !!(condition); \ bool __ret_once = false; \ \ diff --git a/include/net/net_debug.h b/include/net/net_debug.h index 1e74684cbbdb..4a79204c8d30 100644 --- a/include/net/net_debug.h +++ b/include/net/net_debug.h @@ -27,7 +27,7 @@ void netdev_info(const struct net_device *dev, const char *format, ...); #define netdev_level_once(level, dev, fmt, ...) \ do { \ - static bool __section(".data.once") __print_once; \ + static bool __section(".data..once") __print_once; \ \ if (!__print_once) { \ __print_once = true; \ -- cgit v1.2.3 From 054a9cd395a79f4a5595f2cd24542e9bca8723c8 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Wed, 20 Nov 2024 08:56:52 +0900 Subject: modpost: rename alias symbol for MODULE_DEVICE_TABLE() This commit renames the alias symbol, __mod____device_table to __mod_device_table____. This change simplifies the code slightly, as there is no longer a need to check both the prefix and suffix. Signed-off-by: Masahiro Yamada --- include/linux/module.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/module.h b/include/linux/module.h index 88ecc5e9f523..3dd79a3d0cbf 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -247,7 +247,7 @@ extern void cleanup_module(void); #ifdef MODULE /* Creates an alias so file2alias.c can find device table. */ #define MODULE_DEVICE_TABLE(type, name) \ -extern typeof(name) __mod_##type##__##name##_device_table \ +extern typeof(name) __mod_device_table__##type##__##name \ __attribute__ ((unused, alias(__stringify(name)))) #else /* !MODULE */ #define MODULE_DEVICE_TABLE(type, name) -- cgit v1.2.3