From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Luis R. Rodriguez" Subject: [RFC v2 5/7] jump_label: port __jump_table to linker tables Date: Fri, 19 Feb 2016 05:45:57 -0800 Message-ID: <1455889559-9428-6-git-send-email-mcgrof@kernel.org> References: <1455889559-9428-1-git-send-email-mcgrof@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1455889559-9428-1-git-send-email-mcgrof@kernel.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de Cc: benh@kernel.crashing.org, ming.lei@canonical.com, masami.hiramatsu.pt@hitachi.com, linux-arch@vger.kernel.org, xen-devel@lists.xensource.com, linux@arm.linux.org.uk, x86@kernel.org, anil.s.keshavamurthy@intel.com, arnd@arndb.de, rusty@rustcorp.com.au, jbaron@akamai.com, boris.ostrovsky@oracle.com, andriy.shevchenko@linux.intel.com, mcb30@ipxe.org, jgross@suse.com, ananth@in.ibm.com, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, luto@amacapital.net, "Luis R. Rodriguez" , david.vrabel@citrix.com, dwmw2@infradead.org, davem@davemloft.net List-Id: xen-devel@lists.xenproject.org Move the __jump_table from the a custom section solution to a generic solution, this avoiding extra vmlinux.lds.h customizations. This also demos the use of the .data (SECTION_DATA) linker tables and of push_section_tbl(). Signed-off-by: Luis R. Rodriguez --- arch/arm/include/asm/jump_label.h | 4 ++-- arch/arm64/include/asm/jump_label.h | 4 ++-- arch/mips/include/asm/jump_label.h | 4 ++-- arch/powerpc/include/asm/jump_label.h | 6 +++--- arch/s390/include/asm/jump_label.h | 4 ++-- arch/sparc/include/asm/jump_label.h | 4 ++-- arch/x86/include/asm/jump_label.h | 9 +++++---- include/asm-generic/vmlinux.lds.h | 4 ---- include/linux/jump_label.h | 5 +++-- kernel/jump_label.c | 16 +++++++++------- kernel/module.c | 4 +++- 11 files changed, 33 insertions(+), 31 deletions(-) diff --git a/arch/arm/include/asm/jump_label.h b/arch/arm/include/asm/jump_label.h index 34f7b6980d21..c1df4f105df3 100644 --- a/arch/arm/include/asm/jump_label.h +++ b/arch/arm/include/asm/jump_label.h @@ -12,7 +12,7 @@ static __always_inline bool arch_static_branch(struct static_key *key, bool bran { asm_volatile_goto("1:\n\t" WASM(nop) "\n\t" - ".pushsection __jump_table, \"aw\"\n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) ".word 1b, %l[l_yes], %c0\n\t" ".popsection\n\t" : : "i" (&((char *)key)[branch]) : : l_yes); @@ -26,7 +26,7 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool { asm_volatile_goto("1:\n\t" WASM(b) " %l[l_yes]\n\t" - ".pushsection __jump_table, \"aw\"\n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) ".word 1b, %l[l_yes], %c0\n\t" ".popsection\n\t" : : "i" (&((char *)key)[branch]) : : l_yes); diff --git a/arch/arm64/include/asm/jump_label.h b/arch/arm64/include/asm/jump_label.h index 1b5e0e843c3a..18f5ca294eaa 100644 --- a/arch/arm64/include/asm/jump_label.h +++ b/arch/arm64/include/asm/jump_label.h @@ -29,7 +29,7 @@ static __always_inline bool arch_static_branch(struct static_key *key, bool branch) { asm goto("1: nop\n\t" - ".pushsection __jump_table, \"aw\"\n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) ".align 3\n\t" ".quad 1b, %l[l_yes], %c0\n\t" ".popsection\n\t" @@ -43,7 +43,7 @@ l_yes: static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch) { asm goto("1: b %l[l_yes]\n\t" - ".pushsection __jump_table, \"aw\"\n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) ".align 3\n\t" ".quad 1b, %l[l_yes], %c0\n\t" ".popsection\n\t" diff --git a/arch/mips/include/asm/jump_label.h b/arch/mips/include/asm/jump_label.h index e77672539e8e..13e70e290830 100644 --- a/arch/mips/include/asm/jump_label.h +++ b/arch/mips/include/asm/jump_label.h @@ -30,7 +30,7 @@ static __always_inline bool arch_static_branch(struct static_key *key, bool bran { asm_volatile_goto("1:\t" NOP_INSN "\n\t" "nop\n\t" - ".pushsection __jump_table, \"aw\"\n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) WORD_INSN " 1b, %l[l_yes], %0\n\t" ".popsection\n\t" : : "i" (&((char *)key)[branch]) : : l_yes); @@ -44,7 +44,7 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool { asm_volatile_goto("1:\tj %l[l_yes]\n\t" "nop\n\t" - ".pushsection __jump_table, \"aw\"\n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) WORD_INSN " 1b, %l[l_yes], %0\n\t" ".popsection\n\t" : : "i" (&((char *)key)[branch]) : : l_yes); diff --git a/arch/powerpc/include/asm/jump_label.h b/arch/powerpc/include/asm/jump_label.h index 47e155f15433..5fffc7b12361 100644 --- a/arch/powerpc/include/asm/jump_label.h +++ b/arch/powerpc/include/asm/jump_label.h @@ -22,7 +22,7 @@ static __always_inline bool arch_static_branch(struct static_key *key, bool bran { asm_volatile_goto("1:\n\t" "nop\n\t" - ".pushsection __jump_table, \"aw\"\n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) JUMP_ENTRY_TYPE "1b, %l[l_yes], %c0\n\t" ".popsection \n\t" : : "i" (&((char *)key)[branch]) : : l_yes); @@ -36,7 +36,7 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool { asm_volatile_goto("1:\n\t" "b %l[l_yes]\n\t" - ".pushsection __jump_table, \"aw\"\n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) JUMP_ENTRY_TYPE "1b, %l[l_yes], %c0\n\t" ".popsection \n\t" : : "i" (&((char *)key)[branch]) : : l_yes); @@ -61,7 +61,7 @@ struct jump_entry { #else #define ARCH_STATIC_BRANCH(LABEL, KEY) \ 1098: nop; \ - .pushsection __jump_table, "aw"; \ + .pushsection .data.tbl.__jump_table.all, "aw"; \ FTR_ENTRY_LONG 1098b, LABEL, KEY; \ .popsection #endif diff --git a/arch/s390/include/asm/jump_label.h b/arch/s390/include/asm/jump_label.h index 7f9fd5e3f1bf..1ebfb7ddcb11 100644 --- a/arch/s390/include/asm/jump_label.h +++ b/arch/s390/include/asm/jump_label.h @@ -15,7 +15,7 @@ static __always_inline bool arch_static_branch(struct static_key *key, bool branch) { asm_volatile_goto("0: brcl 0,"__stringify(JUMP_LABEL_NOP_OFFSET)"\n" - ".pushsection __jump_table, \"aw\"\n" + ".pushsection .data.tbl.__jump_table.all, \"aw\"\n" ".balign 8\n" ".quad 0b, %l[label], %0\n" ".popsection\n" @@ -29,7 +29,7 @@ label: static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch) { asm_volatile_goto("0: brcl 15, %l[label]\n" - ".pushsection __jump_table, \"aw\"\n" + ".pushsection .data.tbl.__jump_table.all, \"aw\"\n" ".balign 8\n" ".quad 0b, %l[label], %0\n" ".popsection\n" diff --git a/arch/sparc/include/asm/jump_label.h b/arch/sparc/include/asm/jump_label.h index 62d0354d1727..848bece455bb 100644 --- a/arch/sparc/include/asm/jump_label.h +++ b/arch/sparc/include/asm/jump_label.h @@ -12,7 +12,7 @@ static __always_inline bool arch_static_branch(struct static_key *key, bool bran asm_volatile_goto("1:\n\t" "nop\n\t" "nop\n\t" - ".pushsection __jump_table, \"aw\"\n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) ".align 4\n\t" ".word 1b, %l[l_yes], %c0\n\t" ".popsection \n\t" @@ -28,7 +28,7 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool asm_volatile_goto("1:\n\t" "b %l[l_yes]\n\t" "nop\n\t" - ".pushsection __jump_table, \"aw\"\n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) ".align 4\n\t" ".word 1b, %l[l_yes], %c0\n\t" ".popsection \n\t" diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h index adc54c12cbd1..5b80a0e755df 100644 --- a/arch/x86/include/asm/jump_label.h +++ b/arch/x86/include/asm/jump_label.h @@ -29,12 +29,13 @@ #include #include +#include static __always_inline bool arch_static_branch(struct static_key *key, bool branch) { asm_volatile_goto("1:" ".byte " __stringify(STATIC_KEY_INIT_NOP) "\n\t" - ".pushsection __jump_table, \"aw\" \n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) _ASM_ALIGN "\n\t" _ASM_PTR "1b, %l[l_yes], %c0 + %c1 \n\t" ".popsection \n\t" @@ -50,7 +51,7 @@ static __always_inline bool arch_static_branch_jump(struct static_key *key, bool asm_volatile_goto("1:" ".byte 0xe9\n\t .long %l[l_yes] - 2f\n\t" "2:\n\t" - ".pushsection __jump_table, \"aw\" \n\t" + push_section_tbl(SECTION_DATA, __jump_table, all, aw) _ASM_ALIGN "\n\t" _ASM_PTR "1b, %l[l_yes], %c0 + %c1 \n\t" ".popsection \n\t" @@ -85,7 +86,7 @@ struct jump_entry { .else .byte STATIC_KEY_INIT_NOP .endif - .pushsection __jump_table, "aw" + .pushsection .data.tbl.__jump_table.all, "aw" _ASM_ALIGN _ASM_PTR .Lstatic_jump_\@, \target, \key .popsection @@ -101,7 +102,7 @@ struct jump_entry { .long \target - .Lstatic_jump_after_\@ .Lstatic_jump_after_\@: .endif - .pushsection __jump_table, "aw" + .pushsection .data.tbl.__jump_table.all, "aw" _ASM_ALIGN _ASM_PTR .Lstatic_jump_\@, \target, \key + 1 .popsection diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 91815fb1f2fa..11e1adcbcb24 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -210,10 +210,6 @@ STRUCT_ALIGN(); \ *(__tracepoints) \ /* implement dynamic printk debug */ \ - . = ALIGN(8); \ - VMLINUX_SYMBOL(__start___jump_table) = .; \ - *(__jump_table) \ - VMLINUX_SYMBOL(__stop___jump_table) = .; \ . = ALIGN(8); \ VMLINUX_SYMBOL(__start___verbose) = .; \ *(__verbose) \ diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index 0536524bb9eb..42b68b1e4a39 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -1,6 +1,8 @@ #ifndef _LINUX_JUMP_LABEL_H #define _LINUX_JUMP_LABEL_H +#include + /* * Jump label support * @@ -138,8 +140,7 @@ static __always_inline bool static_key_true(struct static_key *key) return !arch_static_branch(key, true); } -extern struct jump_entry __start___jump_table[]; -extern struct jump_entry __stop___jump_table[]; +DECLARE_LINKTABLE_DATA(struct jump_entry, __jump_table); extern void jump_label_init(void); extern void jump_label_lock(void); diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 05254eeb4b4e..66d6e24148be 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -17,6 +17,8 @@ #ifdef HAVE_JUMP_LABEL +DEFINE_LINKTABLE_DATA(struct jump_entry, __jump_table); + /* mutex to protect coming/going of the the jump_label table */ static DEFINE_MUTEX(jump_label_mutex); @@ -200,15 +202,14 @@ static void __jump_label_update(struct static_key *key, void __init jump_label_init(void) { - struct jump_entry *iter_start = __start___jump_table; - struct jump_entry *iter_stop = __stop___jump_table; struct static_key *key = NULL; struct jump_entry *iter; jump_label_lock(); - jump_label_sort_entries(iter_start, iter_stop); + jump_label_sort_entries(LINKTABLE_START(__jump_table), + LINKTABLE_END(__jump_table)); - for (iter = iter_start; iter < iter_stop; iter++) { + LINKTABLE_FOR_EACH(iter, __jump_table) { struct static_key *iterk; /* rewrite NOPs */ @@ -450,8 +451,9 @@ early_initcall(jump_label_init_module); */ int jump_label_text_reserved(void *start, void *end) { - int ret = __jump_label_text_reserved(__start___jump_table, - __stop___jump_table, start, end); + int ret = __jump_label_text_reserved(LINKTABLE_START(__jump_table), + LINKTABLE_END(__jump_table), + start, end); if (ret) return ret; @@ -464,7 +466,7 @@ int jump_label_text_reserved(void *start, void *end) static void jump_label_update(struct static_key *key) { - struct jump_entry *stop = __stop___jump_table; + struct jump_entry *stop = LINKTABLE_END(__jump_table); struct jump_entry *entry = static_key_entries(key); #ifdef CONFIG_MODULES struct module *mod; diff --git a/kernel/module.c b/kernel/module.c index 9537da37ce87..42249ee8e462 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2930,7 +2930,9 @@ static int find_module_sections(struct module *mod, struct load_info *info) &mod->num_tracepoints); #endif #ifdef HAVE_JUMP_LABEL - mod->jump_entries = section_objs(info, "__jump_table", + mod->jump_entries = section_objs(info, + SECTION_TBL(SECTION_DATA, + __jump_table,), sizeof(*mod->jump_entries), &mod->num_jump_entries); #endif -- 2.7.0