Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932436AbWIZWGV (ORCPT ); Tue, 26 Sep 2006 18:06:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932438AbWIZWGU (ORCPT ); Tue, 26 Sep 2006 18:06:20 -0400 Received: from tomts22-srv.bellnexxia.net ([209.226.175.184]:35464 "EHLO tomts22-srv.bellnexxia.net") by vger.kernel.org with ESMTP id S932436AbWIZWGS (ORCPT ); Tue, 26 Sep 2006 18:06:18 -0400 Date: Tue, 26 Sep 2006 18:06:04 -0400 From: Mathieu Desnoyers To: Martin Bligh , "Frank Ch. Eigler" , Masami Hiramatsu , prasanna@in.ibm.com, Andrew Morton , Ingo Molnar , Mathieu Desnoyers , Paul Mundt , linux-kernel , Jes Sorensen , Tom Zanussi , Richard J Moore , Michel Dagenais , Christoph Hellwig , Greg Kroah-Hartman , Thomas Gleixner , William Cohen , ltt-dev@shafik.org, systemtap@sources.redhat.com, Alan Cox , Jeremy Fitzhardinge , Karim Yaghmour , Pavel Machek , Joe Perches , "Randy.Dunlap" , "Jose R. Santos" Subject: [PATCH] Linux Kernel Markers 0.14 for 2.6.17 Message-ID: <20060926220604.GA30396@Krystal> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.4.32-grsec (i686) X-Uptime: 17:53:11 up 34 days, 19:01, 3 users, load average: 0.11, 0.30, 0.31 User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 38205 Lines: 1543 Hi, Constructing on Jeremy Fitzhardinge's comments about gcc optimizations, I rewrote (once more) the markers mechanism so that the optimized mode does not jump between two different inline asm. Instead, the optimized version uses a load immediate (in assembly) that will be used by a test to decide of a branch (in C). The generic, non optimized version, now does almost the same as the optimized version, but instead of using an immediate value, it uses a value in memory which must therefore be loaded before each test. On x86, the result of the fast path is now (the call is put far from the "hot" instructions at the end of the function) : ... 70: b0 00 mov $0x0,%al (load 0 in al) 72: 84 c0 test %al,%al 74: 75 57 jne cd (not taken) .... Compared to the generic version (the call is also put at the end of the function) : ... 64: 0f b6 05 07 00 00 00 movzbl 0x7,%eax (load eax from memory) 6b: 84 c0 test %al,%al 6d: 75 4a jne b9 (not taken) ... I also added the powerpc optimization (not tested yet though). Comments are welcome, Mathieu ---BEGIN--- diff --git a/Makefile b/Makefile index 1700d3f..78ed30f 100644 --- a/Makefile +++ b/Makefile @@ -301,7 +301,8 @@ # Use LINUXINCLUDE when you must referen # Needed to be compatible with the O= option LINUXINCLUDE := -Iinclude \ $(if $(KBUILD_SRC),-Iinclude2 -I$(srctree)/include) \ - -include include/linux/autoconf.h + -include include/linux/autoconf.h \ + -include include/linux/marker.h CPPFLAGS := -D__KERNEL__ $(LINUXINCLUDE) diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig index 213c785..95c1d1b 100644 --- a/arch/alpha/Kconfig +++ b/arch/alpha/Kconfig @@ -630,6 +630,12 @@ source "fs/Kconfig" source "arch/alpha/oprofile/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/alpha/Kconfig.debug" source "security/Kconfig" diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 08b7cc9..4c03f09 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -871,6 +871,12 @@ source "fs/Kconfig" source "arch/arm/oprofile/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/arm/Kconfig.debug" source "security/Kconfig" diff --git a/arch/arm26/Kconfig b/arch/arm26/Kconfig index cf4ebf4..f34e157 100644 --- a/arch/arm26/Kconfig +++ b/arch/arm26/Kconfig @@ -232,6 +232,12 @@ source "drivers/misc/Kconfig" source "drivers/usb/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/arm26/Kconfig.debug" source "security/Kconfig" diff --git a/arch/cris/Kconfig b/arch/cris/Kconfig index 856b665..84f8efd 100644 --- a/arch/cris/Kconfig +++ b/arch/cris/Kconfig @@ -179,6 +179,12 @@ source "sound/Kconfig" source "drivers/usb/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/cris/Kconfig.debug" source "security/Kconfig" diff --git a/arch/frv/Kconfig b/arch/frv/Kconfig index 95a3892..8708a75 100644 --- a/arch/frv/Kconfig +++ b/arch/frv/Kconfig @@ -345,6 +345,12 @@ source "drivers/Kconfig" source "fs/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/frv/Kconfig.debug" source "security/Kconfig" diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig index cabf0bf..bdb67ed 100644 --- a/arch/h8300/Kconfig +++ b/arch/h8300/Kconfig @@ -197,6 +197,12 @@ endmenu source "fs/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/h8300/Kconfig.debug" source "security/Kconfig" diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig index 8dfa305..e6cc7da 100644 --- a/arch/i386/Kconfig +++ b/arch/i386/Kconfig @@ -1081,6 +1081,9 @@ config KPROBES a probepoint and specifies the callback. Kprobes is useful for kernel debugging, non-intrusive instrumentation and testing. If in doubt, say "N". + +source "kernel/Kconfig.marker" + endmenu source "arch/i386/Kconfig.debug" diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index 0f3076a..2342975 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -499,6 +499,9 @@ config KPROBES a probepoint and specifies the callback. Kprobes is useful for kernel debugging, non-intrusive instrumentation and testing. If in doubt, say "N". + +source "kernel/Kconfig.marker" + endmenu source "arch/ia64/Kconfig.debug" diff --git a/arch/m32r/Kconfig b/arch/m32r/Kconfig index 41fd490..50f0a8e 100644 --- a/arch/m32r/Kconfig +++ b/arch/m32r/Kconfig @@ -386,6 +386,12 @@ source "fs/Kconfig" source "arch/m32r/oprofile/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/m32r/Kconfig.debug" source "security/Kconfig" diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index 805b81f..5af9e00 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -652,6 +652,12 @@ endmenu source "fs/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/m68k/Kconfig.debug" source "security/Kconfig" diff --git a/arch/m68knommu/Kconfig b/arch/m68knommu/Kconfig index 3cde682..bd01cc0 100644 --- a/arch/m68knommu/Kconfig +++ b/arch/m68knommu/Kconfig @@ -652,6 +652,12 @@ source "drivers/Kconfig" source "fs/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/m68knommu/Kconfig.debug" source "security/Kconfig" diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index e8ff09f..4d5dbf9 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1850,6 +1850,12 @@ source "fs/Kconfig" source "arch/mips/oprofile/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/mips/Kconfig.debug" source "security/Kconfig" diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index 910fb3a..a0a7dd7 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -251,6 +251,12 @@ source "fs/Kconfig" source "arch/parisc/oprofile/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/parisc/Kconfig.debug" source "security/Kconfig" diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 6729c98..44f25b5 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -1011,6 +1011,9 @@ config KPROBES a probepoint and specifies the callback. Kprobes is useful for kernel debugging, non-intrusive instrumentation and testing. If in doubt, say "N". + +source "kernel/Kconfig.marker" + endmenu source "arch/powerpc/Kconfig.debug" diff --git a/arch/ppc/Kconfig b/arch/ppc/Kconfig index e9a8f5d..ca871ab 100644 --- a/arch/ppc/Kconfig +++ b/arch/ppc/Kconfig @@ -1412,6 +1412,12 @@ source "lib/Kconfig" source "arch/powerpc/oprofile/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/ppc/Kconfig.debug" source "security/Kconfig" diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 01c5c08..57600b5 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -476,6 +476,12 @@ source "fs/Kconfig" source "arch/s390/oprofile/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/s390/Kconfig.debug" source "security/Kconfig" diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index 2bcecf4..0fd24d3 100644 --- a/arch/sh/Kconfig +++ b/arch/sh/Kconfig @@ -644,6 +644,12 @@ source "fs/Kconfig" source "arch/sh/oprofile/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/sh/Kconfig.debug" source "security/Kconfig" diff --git a/arch/sh64/Kconfig b/arch/sh64/Kconfig index 58c678e..f4ecb4d 100644 --- a/arch/sh64/Kconfig +++ b/arch/sh64/Kconfig @@ -276,6 +276,12 @@ source "fs/Kconfig" source "arch/sh64/oprofile/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/sh64/Kconfig.debug" source "security/Kconfig" diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 9431e96..de02311 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -289,6 +289,12 @@ endmenu source "fs/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/sparc/Kconfig.debug" source "security/Kconfig" diff --git a/arch/sparc64/Kconfig b/arch/sparc64/Kconfig index 43a66f5..971f5e2 100644 --- a/arch/sparc64/Kconfig +++ b/arch/sparc64/Kconfig @@ -419,6 +419,9 @@ config KPROBES a probepoint and specifies the callback. Kprobes is useful for kernel debugging, non-intrusive instrumentation and testing. If in doubt, say "N". + +source "kernel/Kconfig.marker" + endmenu source "arch/sparc64/Kconfig.debug" diff --git a/arch/um/Kconfig b/arch/um/Kconfig index 76e85bb..9481883 100644 --- a/arch/um/Kconfig +++ b/arch/um/Kconfig @@ -312,4 +312,10 @@ config INPUT bool default n +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/um/Kconfig.debug" diff --git a/arch/v850/Kconfig b/arch/v850/Kconfig index 37ec644..6ce651f 100644 --- a/arch/v850/Kconfig +++ b/arch/v850/Kconfig @@ -324,6 +324,12 @@ source "sound/Kconfig" source "drivers/usb/Kconfig" +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/v850/Kconfig.debug" source "security/Kconfig" diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig index 408d44a..6feb011 100644 --- a/arch/x86_64/Kconfig +++ b/arch/x86_64/Kconfig @@ -611,6 +611,9 @@ config KPROBES a probepoint and specifies the callback. Kprobes is useful for kernel debugging, non-intrusive instrumentation and testing. If in doubt, say "N". + +source "kernel/Kconfig.marker" + endmenu source "arch/x86_64/Kconfig.debug" diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index dbeb350..413abb8 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -255,6 +255,12 @@ config EMBEDDED_RAMDISK_IMAGE provide one yourself. endmenu +menu "Instrumentation Support" + +source "kernel/Kconfig.marker" + +endmenu + source "arch/xtensa/Kconfig.debug" source "security/Kconfig" diff --git a/include/asm-alpha/marker.h b/include/asm-alpha/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-alpha/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-arm/marker.h b/include/asm-arm/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-arm/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-arm26/marker.h b/include/asm-arm26/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-arm26/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-cris/marker.h b/include/asm-cris/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-cris/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-frv/marker.h b/include/asm-frv/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-frv/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-generic/marker.h b/include/asm-generic/marker.h new file mode 100644 index 0000000..4dd08fa --- /dev/null +++ b/include/asm-generic/marker.h @@ -0,0 +1,42 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Generic header. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#ifdef CONFIG_MARKERS + +#define MARK(name, format, args...) \ + do { \ + static marker_probe_func *__mark_call_##name = \ + __mark_empty_function; \ + volatile static char __marker_enable_##name = 0; \ + asm volatile( ".section .markers, \"a\";\n\t" \ + ".long %0, %1, %2, %3;\n\t" \ + ".previous;\n\t" \ + : : \ + "m" (*(#name)), \ + "m" (__marker_enable_##name), \ + "m" (__mark_call_##name), \ + "m" (*format)); \ + if(unlikely(__marker_enable_##name)) { \ + preempt_disable(); \ + (*__mark_call_##name)(format, ## args); \ + preempt_enable_no_resched(); \ + } \ + } while(0) + + +#define MARK_ENABLE_IMMEDIATE_OFFSET 0 + +struct __mark_marker { + const char *name; + char *enable; + marker_probe_func **call; + const char *format; +} __attribute__((packed)); + +#endif diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 9d11550..d029043 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -90,6 +90,12 @@ #define RODATA \ __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \ *(__ksymtab_strings) \ } \ + /* Kernel markers : pointers */ \ + .markers : AT(ADDR(.markers) - LOAD_OFFSET) { \ + VMLINUX_SYMBOL(__start___markers) = .; \ + *(.markers) \ + VMLINUX_SYMBOL(__stop___markers) = .; \ + } \ __end_rodata = .; \ . = ALIGN(4096); \ \ diff --git a/include/asm-h8300/marker.h b/include/asm-h8300/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-h8300/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-i386/marker.h b/include/asm-i386/marker.h new file mode 100644 index 0000000..bb88767 --- /dev/null +++ b/include/asm-i386/marker.h @@ -0,0 +1,48 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. i386 architecture optimisations. + * + * (C) Copyright 2006 Mathieu Desnoyers + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#ifdef CONFIG_MARKERS + +#define MARK(name, format, args...) \ + do { \ + static marker_probe_func *__mark_call_##name = \ + __mark_empty_function; \ + char condition; \ + asm volatile( ".section .markers, \"a\";\n\t" \ + ".long %1, 0f, %2, %3;\n\t" \ + ".previous;\n\t" \ + ".align 16;\n\t" \ + "0:\n\t" \ + "movb $0,%0;\n\t" \ + : "=r" (condition) : \ + "m" (*(#name)), \ + "m" (__mark_call_##name), \ + "m" (*format)); \ + __mark_check_format(format, ## args); \ + if(unlikely(condition)) { \ + preempt_disable(); \ + (*__mark_call_##name)(format, ## args); \ + preempt_enable_no_resched(); \ + } \ + } while(0) + +/* Offset of the immediate value from the start of the movb instruction, in + * bytes. */ +#define MARK_ENABLE_IMMEDIATE_OFFSET 1 + +struct __mark_marker { + const char *name; + char *enable; + marker_probe_func **call; + const char *format; +} __attribute__((packed)); + +#endif diff --git a/include/asm-ia64/marker.h b/include/asm-ia64/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-ia64/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-m32r/marker.h b/include/asm-m32r/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-m32r/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-m68k/marker.h b/include/asm-m68k/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-m68k/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-m68knommu/marker.h b/include/asm-m68knommu/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-m68knommu/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-mips/marker.h b/include/asm-mips/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-mips/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-parisc/marker.h b/include/asm-parisc/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-parisc/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-powerpc/marker.h b/include/asm-powerpc/marker.h new file mode 100644 index 0000000..2c76cbe --- /dev/null +++ b/include/asm-powerpc/marker.h @@ -0,0 +1,50 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. PowerPC architecture + * optimisations. + * + * (C) Copyright 2006 Mathieu Desnoyers + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#ifdef CONFIG_MARKERS + +#define MARK(name, format, args...) \ + do { \ + static marker_probe_func *__mark_call_##name = \ + __mark_empty_function; \ + char condition; \ + asm volatile( ".section .markers, \"a\";\n\t" \ + ".long %1, 0f, %2, %3;\n\t" \ + ".previous;\n\t" \ + ".align 32;\n\t" \ + "0:\n\t" \ + "li $0,%0;\n\t" \ + : "=r" (condition) : \ + "m" (*(#name)), \ + "m" (__mark_call_##name), \ + "m" (*format)); \ + __mark_check_format(format, ## args); \ + if(unlikely(condition)) { \ + preempt_disable(); \ + (*__mark_call_##name)(format, ## args); \ + preempt_enable_no_resched(); \ + } \ + } while(0) + + +/* Offset of the immediate value from the start of the addi instruction (result + * of the li mnemonic), in bytes. */ +#define MARK_ENABLE_IMMEDIATE_OFFSET 2 + +struct __mark_marker { + const char *name; + short *enable; + marker_probe_func **call; + const char *format; +} __attribute__((packed)); + +#endif diff --git a/include/asm-ppc/marker.h b/include/asm-ppc/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-ppc/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-ppc64/marker.h b/include/asm-ppc64/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-ppc64/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-s390/marker.h b/include/asm-s390/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-s390/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-sh/marker.h b/include/asm-sh/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-sh/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-sh64/marker.h b/include/asm-sh64/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-sh64/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-sparc/marker.h b/include/asm-sparc/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-sparc/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-sparc64/marker.h b/include/asm-sparc64/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-sparc64/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-um/marker.h b/include/asm-um/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-um/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-v850/marker.h b/include/asm-v850/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-v850/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-x86_64/marker.h b/include/asm-x86_64/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-x86_64/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/asm-xtensa/marker.h b/include/asm-xtensa/marker.h new file mode 100644 index 0000000..8d9467f --- /dev/null +++ b/include/asm-xtensa/marker.h @@ -0,0 +1,13 @@ +/* + * marker.h + * + * Code markup for dynamic and static tracing. Architecture specific + * optimisations. + * + * No optimisation implemented. + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#include diff --git a/include/linux/marker.h b/include/linux/marker.h new file mode 100644 index 0000000..71909f0 --- /dev/null +++ b/include/linux/marker.h @@ -0,0 +1,65 @@ +#ifndef _LINUX_MARKER_H +#define _LINUX_MARKER_H + +/* + * marker.h + * + * Code markup for dynamic and static tracing. + * + * Example : + * + * MARK(subsystem_event, "%d %s", someint, somestring); + * Where : + * - Subsystem is the name of your subsystem. + * - event is the name of the event to mark. + * - "%d %s" is the formatted string for printk. + * - someint is an integer. + * - somestring is a char *. + * + * - Dynamically overridable function call based on marker mechanism + * from Frank Ch. Eigler . + * - Thanks to Jeremy Fitzhardinge for his constructive + * criticism about gcc optimization related issues. + * + * The marker mechanism supports multiple instances of the same marker. + * Markers can be put in inline functions, inlined static functions and + * unrolled loops. + * + * (C) Copyright 2006 Mathieu Desnoyers + * + * This file is released under the GPLv2. + * See the file COPYING for more details. + */ + +#ifndef __ASSEMBLY__ + +typedef void marker_probe_func(const char *fmt, ...); + +#ifndef CONFIG_MARKERS_DISABLE_OPTIMIZATION +#include +#else +#include +#endif + +#define MARK_NOARGS " " +#define MARK_MAX_FORMAT_LEN 1024 + +#ifndef CONFIG_MARKERS +#define MARK(name, format, args...) \ + __mark_check_format(format, ## args) +#endif + +static inline __attribute__ ((format (printf, 1, 2))) +void __mark_check_format(const char *fmt, ...) +{ } + +extern marker_probe_func __mark_empty_function; + +extern int marker_set_probe(const char *name, const char *format, + marker_probe_func *probe); + +extern int marker_remove_probe(marker_probe_func *probe); +extern int marker_list_probe(marker_probe_func *probe); + +#endif +#endif diff --git a/include/linux/module.h b/include/linux/module.h index eaec13d..5689857 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -254,6 +254,8 @@ struct module const struct kernel_symbol *syms; unsigned int num_syms; const unsigned long *crcs; + const struct __mark_marker *markers; + unsigned int num_markers; /* GPL-only exported symbols. */ const struct kernel_symbol *gpl_syms; diff --git a/kernel/Kconfig.marker b/kernel/Kconfig.marker new file mode 100644 index 0000000..448e2db --- /dev/null +++ b/kernel/Kconfig.marker @@ -0,0 +1,17 @@ +# Code markers configuration + +config MARKERS + bool "Activate markers" + select MODULES + default n + help + Place an empty function call at each marker site. Can by + dynamically changed for a probe function. + +config MARKERS_DISABLE_OPTIMIZATION + bool "Disable architecture specific marker optimization" + depends EMBEDDED + default n + help + Disable code replacement jump optimisations. Especially useful if your + code is in a read-only rom/flash. diff --git a/kernel/module.c b/kernel/module.c index bbe0486..e451527 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -123,6 +123,8 @@ extern const struct kernel_symbol __stop extern const unsigned long __start___kcrctab[]; extern const unsigned long __start___kcrctab_gpl[]; extern const unsigned long __start___kcrctab_gpl_future[]; +extern const struct __mark_marker __start___markers[]; +extern const struct __mark_marker __stop___markers[]; #ifndef CONFIG_MODVERSIONS #define symversion(base, idx) NULL @@ -236,6 +238,164 @@ static struct module *find_module(const return NULL; } +#ifdef CONFIG_MARKERS +void __mark_empty_function(const char *fmt, ...) +{ +} +EXPORT_SYMBOL(__mark_empty_function); + +#define MARK_ENABLE_OFFSET(a) \ + (typeof(a))((char*)a+MARK_ENABLE_IMMEDIATE_OFFSET) + +static int marker_set_probe_range(const char *name, + const char *format, + marker_probe_func *probe, + const struct __mark_marker *begin, + const struct __mark_marker *end) +{ + const struct __mark_marker *iter; + int found = 0; + + for(iter = begin; iter < end; iter++) { + if (strcmp(name, iter->name) == 0) { + if (format && strcmp(format, iter->format) != 0) { + printk(KERN_NOTICE + "Format mismatch for probe %s " + "(%s), marker (%s)\n", + name, + format, + iter->format); + continue; + } + if (probe == __mark_empty_function) { + if (*iter->call != __mark_empty_function) { + found++; + *MARK_ENABLE_OFFSET(iter->enable) = 0; + *iter->call = __mark_empty_function; + } + } else { + if (*iter->call != __mark_empty_function) { + if (*iter->call != probe) { + printk(KERN_NOTICE + "Marker %s busy, " + "probe %p already " + "installed\n", + name, + *iter->call); + continue; + } + } else { + found++; + *iter->call = probe; + *MARK_ENABLE_OFFSET(iter->enable) = 1; + } + } + } + } + return found; +} + +static int marker_remove_probe_range(marker_probe_func *probe, + const struct __mark_marker *begin, + const struct __mark_marker *end) +{ + const struct __mark_marker *iter; + int found = 0; + + for(iter = begin; iter < end; iter++) { + if (*iter->call == probe) { + *MARK_ENABLE_OFFSET(iter->enable) = 0; + *iter->call = __mark_empty_function; + found++; + } + } + return found; +} + +static int marker_list_probe_range(marker_probe_func *probe, + const struct __mark_marker *begin, + const struct __mark_marker *end) +{ + const struct __mark_marker *iter; + int found = 0; + + for(iter = begin; iter < end; iter++) { + if (probe) + if (probe != *iter->call) continue; + printk("name %s \n", iter->name); + printk(" enable %u ", *MARK_ENABLE_OFFSET(iter->enable)); + printk(" func 0x%p format \"%s\"\n", + *iter->call, iter->format); + found++; + } + return found; +} +/* markers use the modlist_lock to to synchronise */ +int marker_set_probe(const char *name, const char *format, + marker_probe_func *probe) +{ + struct module *mod; + int found = 0; + unsigned long flags; + + spin_lock_irqsave(&modlist_lock, flags); + /* Core kernel markers */ + found += marker_set_probe_range(name, format, probe, + __start___markers, __stop___markers); + /* Markers in modules. */ + list_for_each_entry(mod, &modules, list) { + found += marker_set_probe_range(name, format, probe, + mod->markers, mod->markers+mod->num_markers); + } + spin_unlock_irqrestore(&modlist_lock, flags); + return found; +} +EXPORT_SYMBOL(marker_set_probe); + +int marker_remove_probe(marker_probe_func *probe) +{ + struct module *mod; + int found = 0; + unsigned long flags; + + spin_lock_irqsave(&modlist_lock, flags); + /* Core kernel markers */ + found += marker_remove_probe_range(probe, + __start___markers, __stop___markers); + /* Markers in modules. */ + list_for_each_entry(mod, &modules, list) { + found += marker_remove_probe_range(probe, + mod->markers, mod->markers+mod->num_markers); + } + spin_unlock_irqrestore(&modlist_lock, flags); + return found; +} +EXPORT_SYMBOL(marker_remove_probe); + +int marker_list_probe(marker_probe_func *probe) +{ + struct module *mod; + int found = 0; + unsigned long flags; + + spin_lock_irqsave(&modlist_lock, flags); + /* Core kernel markers */ + printk("Listing kernel markers\n"); + found += marker_list_probe_range(probe, + __start___markers, __stop___markers); + /* Markers in modules. */ + printk("Listing module markers\n"); + list_for_each_entry(mod, &modules, list) { + printk("Listing markers for module %s\n", mod->name); + found += marker_list_probe_range(probe, + mod->markers, mod->markers+mod->num_markers); + } + spin_unlock_irqrestore(&modlist_lock, flags); + return found; +} +EXPORT_SYMBOL(marker_list_probe); +#endif + #ifdef CONFIG_SMP /* Number of blocks used and allocated. */ static unsigned int pcpu_num_used, pcpu_num_allocated; @@ -1412,7 +1572,7 @@ static struct module *load_module(void _ unsigned int i, symindex = 0, strindex = 0, setupindex, exindex, exportindex, modindex, obsparmindex, infoindex, gplindex, crcindex, gplcrcindex, versindex, pcpuindex, gplfutureindex, - gplfuturecrcindex; + gplfuturecrcindex, markersindex; struct module *mod; long err = 0; void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */ @@ -1502,6 +1662,7 @@ #endif versindex = find_sec(hdr, sechdrs, secstrings, "__versions"); infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo"); pcpuindex = find_pcpusec(hdr, sechdrs, secstrings); + markersindex = find_sec(hdr, sechdrs, secstrings, ".markers"); /* Don't keep modinfo section */ sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC; @@ -1510,6 +1671,11 @@ #ifdef CONFIG_KALLSYMS sechdrs[symindex].sh_flags |= SHF_ALLOC; sechdrs[strindex].sh_flags |= SHF_ALLOC; #endif +#ifdef CONFIG_MARKERS + sechdrs[markersindex].sh_flags |= SHF_ALLOC; +#else + sechdrs[markersindex].sh_flags &= ~(unsigned long)SHF_ALLOC; +#endif /* Check module struct version now, before we try to use module. */ if (!check_modstruct_version(sechdrs, versindex, mod)) { @@ -1642,6 +1808,11 @@ #endif mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr; if (gplfuturecrcindex) mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr; + if (markersindex) { + mod->markers = (void *)sechdrs[markersindex].sh_addr; + mod->num_markers = + sechdrs[markersindex].sh_size / sizeof(*mod->markers); + } #ifdef CONFIG_MODVERSIONS if ((mod->num_syms && !crcindex) || ---END--- ---BEGIN--- /* probe.c * * Loads a function at a marker call site. * * (C) Copyright 2006 Mathieu Desnoyers * * This file is released under the GPLv2. * See the file COPYING for more details. */ #include #include #include /* function to install */ #define DO_MARK1_FORMAT "%d" void do_mark1(const char *format, ...) { va_list ap; int value; va_start(ap, format); value = va_arg(ap, int); printk("value is %d\n", value); va_end(ap); } void do_mark2(const char *format, ...) { va_list ap; va_start(ap, format); vprintk(format, ap); va_end(ap); printk("\n"); } #define DO_MARK3_FORMAT "%d %s %s" void do_mark3(const char *format, ...) { va_list ap; int value; const char *s1, *s2; va_start(ap, format); value = va_arg(ap, int); s1 = va_arg(ap, const char*); s2 = va_arg(ap, const char *); printk("value is %d %s %s\n", value, s1, s2); va_end(ap); } int init_module(void) { int result; result = marker_set_probe("subsys_mark1", DO_MARK1_FORMAT, (marker_probe_func*)do_mark1); if(!result) goto end; result = marker_set_probe("subsys_mark2", NULL, (marker_probe_func*)do_mark2); if(!result) goto cleanup1; result = marker_set_probe("subsys_mark3", DO_MARK3_FORMAT, (marker_probe_func*)do_mark3); if(!result) goto cleanup2; return 0; cleanup2: marker_remove_probe((marker_probe_func*)do_mark2); cleanup1: marker_remove_probe((marker_probe_func*)do_mark1); end: return -EPERM; } void cleanup_module(void) { marker_remove_probe((marker_probe_func*)do_mark1); marker_remove_probe((marker_probe_func*)do_mark2); marker_remove_probe((marker_probe_func*)do_mark3); } MODULE_LICENSE("GPL"); MODULE_AUTHOR("Mathieu Desnoyers"); MODULE_DESCRIPTION("Probe"); ---END--- ---BEGIN--- /* test-mark.c * */ #include #include #include #include #include volatile int x = 7; struct proc_dir_entry *pentry = NULL; static inline void test(struct pt_regs * regs) { MARK(kernel_debug_test, "%d %ld %p", 2, regs->eip, regs); } static int my_open(struct inode *inode, struct file *file) { unsigned int i; for(i=0; i<2; i++) { MARK(subsys_mark1, "%d", 1); } MARK(subsys_mark2, "%d %s %s", 2, "blah2", "blahx"); MARK(subsys_mark3, "%d %s %s", x, "blah3", "blah5"); test(NULL); test(NULL); return -EPERM; } static struct file_operations my_operations = { .open = my_open, }; int init_module(void) { pentry = create_proc_entry("testmark", 0444, NULL); if (pentry) pentry->proc_fops = &my_operations; marker_list_probe(NULL); return 0; } void cleanup_module(void) { remove_proc_entry("testmark", NULL); } MODULE_LICENSE("GPL"); MODULE_AUTHOR("Mathieu Desnoyers"); MODULE_DESCRIPTION("Marker Test"); ---END--- OpenPGP public key: http://krystal.dyndns.org:8080/key/compudj.gpg Key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/