// SPDX-License-Identifier: BSD-2-Clause /* * This single-header library defines a collection of variadic macros for * defining and triggering USDTs (User Statically-Defined Tracepoints): * * - For USDTs without associated semaphore: * USDT(group, name, args...) * * - For USDTs with implicit (transparent to the user) semaphore: * USDT_WITH_SEMA(group, name, args...) * USDT_IS_ACTIVE(group, name) * * - For USDTs with explicit (user-defined and provided) semaphore: * USDT_WITH_EXPLICIT_SEMA(sema, group, name, args...) * USDT_SEMA_IS_ACTIVE(sema) * * all of which emit a NOP instruction into the instruction stream, and so * have *zero* overhead for the surrounding code. USDTs are identified by * a combination of `group` and `name` identifiers, which is used by external * tracing tooling (tracers) for identifying exact USDTs of interest. * * USDTs can have an associated (2-byte) activity counter (USDT semaphore), * automatically maintained by Linux kernel whenever any correctly written * BPF-based tracer is attached to the USDT. This USDT semaphore can be used * to check whether there is a need to do any extra data collection and * processing for a given USDT (if necessary), and otherwise avoid extra work * for a common case of USDT not being traced ("active"). * * See documentation for USDT_WITH_SEMA()/USDT_IS_ACTIVE() or * USDT_WITH_EXPLICIT_SEMA()/USDT_SEMA_IS_ACTIVE() APIs below for details on * working with USDTs with implicitly or explicitly associated * USDT semaphores, respectively. * * There is also some additional data recorded into an auxiliary note * section. The data in the note section describes the operands, in terms of * size and location, used by tracing tooling to know where to find USDT * arguments. Each location is encoded as an assembler operand string. * Tracing tools (bpftrace and BPF-based tracers, systemtap, etc) insert * breakpoints on top of the nop, and decode the location operand-strings, * like an assembler, to find the values being passed. * * The operand strings are selected by the compiler for each operand. * They are constrained by inline-assembler codes.The default is: * * #define USDT_ARG_CONSTRAINT nor * * This is a good default if the operands tend to be integral and * moderate in number (smaller than number of registers). In other * cases, the compiler may report "'asm' requires impossible reload" or * similar. In this case, consider simplifying the macro call (fewer * and simpler operands), reduce optimization, or override the default * constraints string via: * * #define USDT_ARG_CONSTRAINT g * #include * * For some historical description of USDT v3 format (the one used by this * library and generally recognized and assumed by BPF-based tracing tools) * see [0]. The more formal specification can be found at [1]. Additional * argument constraints information can be found at [2]. * * Original SystemTap's sys/sdt.h implementation ([3]) was used as a base for * this USDT library implementation. Current implementation differs *a lot* in * terms of exposed user API and general usability, which was the main goal * and focus of the reimplementation work. Nevertheless, underlying recorded * USDT definitions are fully binary compatible and any USDT-based tooling * should work equally well with USDTs defined by either SystemTap's or this * library's USDT implementation. * * [0] https://ecos.sourceware.org/ml/systemtap/2010-q3/msg00145.html * [1] https://sourceware.org/systemtap/wiki/UserSpaceProbeImplementation * [2] https://gcc.gnu.org/onlinedocs/gcc/Constraints.html * [3] https://sourceware.org/git/?p=systemtap.git;a=blob;f=includes/sys/sdt.h */ #ifndef __USDT_H #define __USDT_H /* * Changelog: * * 0.1.0 * ----- * - Initial release */ #define USDT_MAJOR_VERSION 0 #define USDT_MINOR_VERSION 1 #define USDT_PATCH_VERSION 0 /* C++20 and C23 added __VA_OPT__ as a standard replacement for non-standard `##__VA_ARGS__` extension */ #if (defined(__STDC_VERSION__) && __STDC_VERSION__ > 201710L) || (defined(__cplusplus) && __cplusplus > 201703L) #define __usdt_va_opt 1 #define __usdt_va_args(...) __VA_OPT__(,) __VA_ARGS__ #else #define __usdt_va_args(...) , ##__VA_ARGS__ #endif /* * Trigger USDT with `group`:`name` identifier and pass through `args` as its * arguments. Zero arguments are acceptable as well. No USDT semaphore is * associated with this USDT. * * Such "semaphoreless" USDTs are commonly used when there is no extra data * collection or processing needed to collect and prepare USDT arguments and * they are just available in the surrounding code. USDT() macro will just * record their locations in CPU registers or in memory for tracing tooling to * be able to access them, if necessary. */ #ifdef __usdt_va_opt #define USDT(group, name, ...) \ __usdt_probe(group, name, __usdt_sema_none, 0 __VA_OPT__(,) __VA_ARGS__) #else #define USDT(group, name, ...) \ __usdt_probe(group, name, __usdt_sema_none, 0, ##__VA_ARGS__) #endif /* * Trigger USDT with `group`:`name` identifier and pass through `args` as its * arguments. Zero arguments are acceptable as well. USDT also get an * implicitly-defined associated USDT semaphore, which will be "activated" by * tracing tooling and can be used to check whether USDT is being actively * observed. * * USDTs with semaphore are commonly used when there is a need to perform * additional data collection and processing to prepare USDT arguments, which * otherwise might not be necessary for the rest of application logic. In such * case, USDT semaphore can be used to avoid unnecessary extra work. If USDT * is not traced (which is presumed to be a common situation), the associated * USDT semaphore is "inactive", and so there is no need to waste resources to * prepare USDT arguments. Use USDT_IS_ACTIVE(group, name) to check whether * USDT is "active". * * N.B. There is an inherent (albeit short) gap between checking whether USDT * is active and triggering corresponding USDT, in which external tracer can * be attached to an USDT and activate USDT semaphore after the activity check. * If such a race occurs, tracers might miss one USDT execution. Tracers are * expected to accommodate such possibility and this is expected to not be * a problem for applications and tracers. * * N.B. Implicit USDT semaphore defined by USDT_WITH_SEMA() is contained * within a single executable or shared library and is not shared outside * them. I.e., if you use USDT_WITH_SEMA() with the same USDT group and name * identifier across executable and shared library, it will work and won't * conflict, per se, but will define independent USDT semaphores, one for each * shared library/executable in which USDT_WITH_SEMA(group, name) is used. * That is, if you attach to this USDT in one shared library (or executable), * then only USDT semaphore within that shared library (or executable) will be * updated by the kernel, while other libraries (or executable) will not see * activated USDT semaphore. In short, it's best to use unique USDT group:name * identifiers across different shared libraries (and, equivalently, between * executable and shared library). This is advanced consideration and is * rarely (if ever) seen in practice, but just to avoid surprises this is * called out here. (Static libraries become a part of final executable, once * linked by linker, so the above considerations don't apply to them.) */ #ifdef __usdt_va_opt #define USDT_WITH_SEMA(group, name, ...) \ __usdt_probe(group, name, \ __usdt_sema_implicit, __usdt_sema_name(group, name) \ __VA_OPT__(,) __VA_ARGS__) #else #define USDT_WITH_SEMA(group, name, ...) \ __usdt_probe(group, name, \ __usdt_sema_implicit, __usdt_sema_name(group, name), \ ##__VA_ARGS__) #endif struct usdt_sema { volatile unsigned short active; }; /* * Check if USDT with `group`:`name` identifier is "active" (i.e., whether it * is attached to by external tracing tooling and is actively observed). * * This macro can be used to decide whether any additional and potentially * expensive data collection or processing should be done to pass extra * information into the given USDT. It is assumed that USDT is triggered with * USDT_WITH_SEMA() macro which will implicitly define associated USDT * semaphore. (If one needs more control over USDT semaphore, see * USDT_DEFINE_SEMA() and USDT_WITH_EXPLICIT_SEMA() macros below.) * * N.B. Such checks are necessarily racy and speculative. Between checking * whether USDT is active and triggering the USDT itself, tracer can be * detached with no notification. This race should be extremely rare and worst * case should result in one-time wasted extra data collection and processing. */ #define USDT_IS_ACTIVE(group, name) ({ \ extern struct usdt_sema __usdt_sema_name(group, name) \ __usdt_asm_name(__usdt_sema_name(group, name)); \ __usdt_sema_implicit(__usdt_sema_name(group, name)); \ __usdt_sema_name(group, name).active > 0; \ }) /* * APIs for working with user-defined explicit USDT semaphores. * * This is a less commonly used advanced API for use cases in which user needs * an explicit control over (potentially shared across multiple USDTs) USDT * semaphore instance. This can be used when there is a group of logically * related USDTs that all need extra data collection and processing whenever * any of a family of related USDTs are "activated" (i.e., traced). In such * a case, all such related USDTs will be associated with the same shared USDT * semaphore defined with USDT_DEFINE_SEMA() and the USDTs themselves will be * triggered with USDT_WITH_EXPLICIT_SEMA() macros, taking an explicit extra * USDT semaphore identifier as an extra parameter. */ /** * Underlying C global variable name for user-defined USDT semaphore with * `sema` identifier. Could be useful for debugging, but normally shouldn't be * used explicitly. */ #define USDT_SEMA(sema) __usdt_sema_##sema /* * Define storage for user-defined USDT semaphore `sema`. * * Should be used only once in non-header source file to let compiler allocate * space for the semaphore variable. Just like with any other global variable. * * This macro can be used anywhere where global variable declaration is * allowed. Just like with global variable definitions, there should be only * one definition of user-defined USDT semaphore with given `sema` identifier, * otherwise compiler or linker will complain about duplicate variable * definition. * * For C++, it is allowed to use USDT_DEFINE_SEMA() both in global namespace * and inside namespaces (including nested namespaces). Just make sure that * USDT_DECLARE_SEMA() is placed within the namespace where this semaphore is * referenced, or any of its parent namespaces, so the C++ language-level * identifier is visible to the code that needs to reference the semaphore. * At the lowest layer, USDT semaphores have global naming and visibility * (they have a corresponding `__usdt_sema_` symbol, which can be linked * against from C or C++ code, if necessary). To keep it simple, putting * USDT_DECLARE_SEMA() declarations into global namespaces is the simplest * no-brainer solution. All these aspects are irrelevant for plain C, because * C doesn't have namespaces and everything is always in the global namespace. * * N.B. Due to USDT metadata being recorded in non-allocatable ELF note * section, it has limitations when it comes to relocations, which, in * practice, means that it's not possible to correctly share USDT semaphores * between main executable and shared libraries, or even between multiple * shared libraries. USDT semaphore has to be contained to individual shared * library or executable to avoid unpleasant surprises with half-working USDT * semaphores. We enforce this by marking semaphore ELF symbols as having * a hidden visibility. This is quite an advanced use case and consideration * and for most users this should have no consequences whatsoever. */ #define USDT_DEFINE_SEMA(sema) \ struct usdt_sema __usdt_sema_sec USDT_SEMA(sema) \ __usdt_asm_name(USDT_SEMA(sema)) \ __attribute__((visibility("hidden"))) = { 0 } /* * Declare extern reference to user-defined USDT semaphore `sema`. * * Refers to a variable defined in another compilation unit by * USDT_DEFINE_SEMA() and allows to use the same USDT semaphore across * multiple compilation units (i.e., .c and .cpp files). * * See USDT_DEFINE_SEMA() notes above for C++ language usage peculiarities. */ #define USDT_DECLARE_SEMA(sema) \ extern struct usdt_sema USDT_SEMA(sema) __usdt_asm_name(USDT_SEMA(sema)) /* * Check if user-defined USDT semaphore `sema` is "active" (i.e., whether it * is attached to by external tracing tooling and is actively observed). * * This macro can be used to decide whether any additional and potentially * expensive data collection or processing should be done to pass extra * information into USDT(s) associated with USDT semaphore `sema`. * * N.B. Such checks are necessarily racy. Between checking the state of USDT * semaphore and triggering associated USDT(s), the active tracer might attach * or detach. This race should be extremely rare and worst case should result * in one-time missed USDT event or wasted extra data collection and * processing. USDT-using tracers should be written with this in mind and is * not a concern of the application defining USDTs with associated semaphore. */ #define USDT_SEMA_IS_ACTIVE(sema) (USDT_SEMA(sema).active > 0) /* * Invoke USDT specified by `group` and `name` identifiers and associate * explicitly user-defined semaphore `sema` with it. Pass through `args` as * USDT arguments. `args` are optional and zero arguments are acceptable. * * Semaphore is defined with the help of USDT_DEFINE_SEMA() macro and can be * checked whether active with USDT_SEMA_IS_ACTIVE(). */ #ifdef __usdt_va_opt #define USDT_WITH_EXPLICIT_SEMA(sema, group, name, ...) \ __usdt_probe(group, name, __usdt_sema_explicit, USDT_SEMA(sema), ##__VA_ARGS__) #else #define USDT_WITH_EXPLICIT_SEMA(sema, group, name, ...) \ __usdt_probe(group, name, __usdt_sema_explicit, USDT_SEMA(sema) __VA_OPT__(,) __VA_ARGS__) #endif /* * Adjustable implementation aspects */ #ifndef USDT_ARG_CONSTRAINT #if defined __powerpc__ #define USDT_ARG_CONSTRAINT nZr #elif defined __arm__ #define USDT_ARG_CONSTRAINT g #elif defined __loongarch__ #define USDT_ARG_CONSTRAINT nmr #else #define USDT_ARG_CONSTRAINT nor #endif #endif /* USDT_ARG_CONSTRAINT */ #ifndef USDT_NOP #if defined(__ia64__) || defined(__s390__) || defined(__s390x__) #define USDT_NOP nop 0 #else #define USDT_NOP nop #endif #endif /* USDT_NOP */ /* * Implementation details */ /* USDT name for implicitly-defined USDT semaphore, derived from group:name */ #define __usdt_sema_name(group, name) __usdt_sema_##group##__##name /* ELF section into which USDT semaphores are put */ #define __usdt_sema_sec __attribute__((section(".probes"))) #define __usdt_concat(a, b) a ## b #define __usdt_apply(fn, n) __usdt_concat(fn, n) #ifndef __usdt_nth #define __usdt_nth(_, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, N, ...) N #endif #ifndef __usdt_narg #ifdef __usdt_va_opt #define __usdt_narg(...) __usdt_nth(_ __VA_OPT__(,) __VA_ARGS__, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) #else #define __usdt_narg(...) __usdt_nth(_, ##__VA_ARGS__, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) #endif #endif /* __usdt_narg */ #define __usdt_hash # #define __usdt_str_(x) #x #define __usdt_str(x) __usdt_str_(x) #ifndef __usdt_asm_name #define __usdt_asm_name(name) __asm__(__usdt_str(name)) #endif #define __usdt_asm0() "\n" #define __usdt_asm1(x) __usdt_str(x) "\n" #define __usdt_asm2(x, ...) __usdt_str(x) "," __usdt_asm1(__VA_ARGS__) #define __usdt_asm3(x, ...) __usdt_str(x) "," __usdt_asm2(__VA_ARGS__) #define __usdt_asm4(x, ...) __usdt_str(x) "," __usdt_asm3(__VA_ARGS__) #define __usdt_asm5(x, ...) __usdt_str(x) "," __usdt_asm4(__VA_ARGS__) #define __usdt_asm6(x, ...) __usdt_str(x) "," __usdt_asm5(__VA_ARGS__) #define __usdt_asm7(x, ...) __usdt_str(x) "," __usdt_asm6(__VA_ARGS__) #define __usdt_asm8(x, ...) __usdt_str(x) "," __usdt_asm7(__VA_ARGS__) #define __usdt_asm9(x, ...) __usdt_str(x) "," __usdt_asm8(__VA_ARGS__) #define __usdt_asm10(x, ...) __usdt_str(x) "," __usdt_asm9(__VA_ARGS__) #define __usdt_asm11(x, ...) __usdt_str(x) "," __usdt_asm10(__VA_ARGS__) #define __usdt_asm12(x, ...) __usdt_str(x) "," __usdt_asm11(__VA_ARGS__) #define __usdt_asm(...) __usdt_apply(__usdt_asm, __usdt_narg(__VA_ARGS__))(__VA_ARGS__) #ifdef __LP64__ #define __usdt_asm_addr .8byte #else #define __usdt_asm_addr .4byte #endif #define __usdt_asm_strz_(x) __usdt_asm1(.asciz #x) #define __usdt_asm_strz(x) __usdt_asm_strz_(x) #define __usdt_asm_str_(x) __usdt_asm1(.ascii #x) #define __usdt_asm_str(x) __usdt_asm_str_(x) /* "semaphoreless" USDT case */ #ifndef __usdt_sema_none #define __usdt_sema_none(sema) #endif /* implicitly defined __usdt_sema__group__name semaphore (using weak symbols) */ #ifndef __usdt_sema_implicit #define __usdt_sema_implicit(sema) \ __asm__ __volatile__ ( \ __usdt_asm1(.ifndef sema) \ __usdt_asm3( .pushsection .probes, "aw", "progbits") \ __usdt_asm1( .weak sema) \ __usdt_asm1( .hidden sema) \ __usdt_asm1( .align 2) \ __usdt_asm1(sema:) \ __usdt_asm1( .zero 2) \ __usdt_asm2( .type sema, @object) \ __usdt_asm2( .size sema, 2) \ __usdt_asm1( .popsection) \ __usdt_asm1(.endif) \ ); #endif /* externally defined semaphore using USDT_DEFINE_SEMA() and passed explicitly by user */ #ifndef __usdt_sema_explicit #define __usdt_sema_explicit(sema) \ __asm__ __volatile__ ("" :: "m" (sema)); #endif /* main USDT definition (nop and .note.stapsdt metadata) */ #define __usdt_probe(group, name, sema_def, sema, ...) do { \ sema_def(sema) \ __asm__ __volatile__ ( \ __usdt_asm( 990: USDT_NOP) \ __usdt_asm3( .pushsection .note.stapsdt, "", "note") \ __usdt_asm1( .balign 4) \ __usdt_asm3( .4byte 992f-991f,994f-993f,3) \ __usdt_asm1(991: .asciz "stapsdt") \ __usdt_asm1(992: .balign 4) \ __usdt_asm1(993: __usdt_asm_addr 990b) \ __usdt_asm1( __usdt_asm_addr _.stapsdt.base) \ __usdt_asm1( __usdt_asm_addr sema) \ __usdt_asm_strz(group) \ __usdt_asm_strz(name) \ __usdt_asm_args(__VA_ARGS__) \ __usdt_asm1( .ascii "\0") \ __usdt_asm1(994: .balign 4) \ __usdt_asm1( .popsection) \ __usdt_asm1(.ifndef _.stapsdt.base) \ __usdt_asm5( .pushsection .stapsdt.base,"aG","progbits",.stapsdt.base,comdat)\ __usdt_asm1( .weak _.stapsdt.base) \ __usdt_asm1( .hidden _.stapsdt.base) \ __usdt_asm1(_.stapsdt.base:) \ __usdt_asm1( .space 1) \ __usdt_asm2( .size _.stapsdt.base, 1) \ __usdt_asm1( .popsection) \ __usdt_asm1(.endif) \ :: __usdt_asm_ops(__VA_ARGS__) \ ); \ } while (0) /* * NB: gdb PR24541 highlighted an unspecified corner of the sdt.h * operand note format. * * The named register may be a longer or shorter (!) alias for the * storage where the value in question is found. For example, on * i386, 64-bit value may be put in register pairs, and a register * name stored would identify just one of them. Previously, gcc was * asked to emit the %w[id] (16-bit alias of some registers holding * operands), even when a wider 32-bit value was used. * * Bottom line: the byte-width given before the @ sign governs. If * there is a mismatch between that width and that of the named * register, then a sys/sdt.h note consumer may need to employ * architecture-specific heuristics to figure out where the compiler * has actually put the complete value. */ #if defined(__powerpc__) || defined(__powerpc64__) #define __usdt_argref(id) %I[id]%[id] #elif defined(__i386__) #define __usdt_argref(id) %k[id] /* gcc.gnu.org/PR80115 sourceware.org/PR24541 */ #else #define __usdt_argref(id) %[id] #endif #define __usdt_asm_arg(n) __usdt_asm_str(%c[__usdt_asz##n]) \ __usdt_asm1(.ascii "@") \ __usdt_asm_str(__usdt_argref(__usdt_aval##n)) #define __usdt_asm_args0 /* no arguments */ #define __usdt_asm_args1 __usdt_asm_arg(1) #define __usdt_asm_args2 __usdt_asm_args1 __usdt_asm1(.ascii " ") __usdt_asm_arg(2) #define __usdt_asm_args3 __usdt_asm_args2 __usdt_asm1(.ascii " ") __usdt_asm_arg(3) #define __usdt_asm_args4 __usdt_asm_args3 __usdt_asm1(.ascii " ") __usdt_asm_arg(4) #define __usdt_asm_args5 __usdt_asm_args4 __usdt_asm1(.ascii " ") __usdt_asm_arg(5) #define __usdt_asm_args6 __usdt_asm_args5 __usdt_asm1(.ascii " ") __usdt_asm_arg(6) #define __usdt_asm_args7 __usdt_asm_args6 __usdt_asm1(.ascii " ") __usdt_asm_arg(7) #define __usdt_asm_args8 __usdt_asm_args7 __usdt_asm1(.ascii " ") __usdt_asm_arg(8) #define __usdt_asm_args9 __usdt_asm_args8 __usdt_asm1(.ascii " ") __usdt_asm_arg(9) #define __usdt_asm_args10 __usdt_asm_args9 __usdt_asm1(.ascii " ") __usdt_asm_arg(10) #define __usdt_asm_args11 __usdt_asm_args10 __usdt_asm1(.ascii " ") __usdt_asm_arg(11) #define __usdt_asm_args12 __usdt_asm_args11 __usdt_asm1(.ascii " ") __usdt_asm_arg(12) #define __usdt_asm_args(...) __usdt_apply(__usdt_asm_args, __usdt_narg(__VA_ARGS__)) #define __usdt_is_arr(x) (__builtin_classify_type(x) == 14 || __builtin_classify_type(x) == 5) #define __usdt_arg_size(x) (__usdt_is_arr(x) ? sizeof(void *) : sizeof(x)) /* * We can't use __builtin_choose_expr() in C++, so fall back to table-based * signedness determination for known types, utilizing templates magic. */ #ifdef __cplusplus #define __usdt_is_signed(x) (!__usdt_is_arr(x) && __usdt_t<__typeof(x)>::is_signed) #include template struct __usdt_t { static const bool is_signed = false; }; template struct __usdt_t : public __usdt_t {}; template struct __usdt_t : public __usdt_t {}; #define __usdt_def_signed(T) \ template<> struct __usdt_t { static const bool is_signed = true; }; \ template<> struct __usdt_t { static const bool is_signed = true; }; \ template<> struct __usdt_t { static const bool is_signed = true; }; \ template<> struct __usdt_t { static const bool is_signed = true; } #define __usdt_maybe_signed(T) \ template<> struct __usdt_t { static const bool is_signed = (T)-1 < (T)1; }; \ template<> struct __usdt_t { static const bool is_signed = (T)-1 < (T)1; }; \ template<> struct __usdt_t { static const bool is_signed = (T)-1 < (T)1; }; \ template<> struct __usdt_t { static const bool is_signed = (T)-1 < (T)1; } __usdt_def_signed(signed char); __usdt_def_signed(short); __usdt_def_signed(int); __usdt_def_signed(long); __usdt_def_signed(long long); __usdt_maybe_signed(char); __usdt_maybe_signed(wchar_t); #else /* !__cplusplus */ #define __usdt_is_inttype(x) (__builtin_classify_type(x) >= 1 && __builtin_classify_type(x) <= 4) #define __usdt_inttype(x) __typeof(__builtin_choose_expr(__usdt_is_inttype(x), (x), 0U)) #define __usdt_is_signed(x) ((__usdt_inttype(x))-1 < (__usdt_inttype(x))1) #endif /* __cplusplus */ #define __usdt_asm_op(n, x) \ [__usdt_asz##n] "n" ((__usdt_is_signed(x) ? (int)-1 : 1) * (int)__usdt_arg_size(x)), \ [__usdt_aval##n] __usdt_str(USDT_ARG_CONSTRAINT)(x) #define __usdt_asm_ops0() [__usdt_dummy] "g" (0) #define __usdt_asm_ops1(x) __usdt_asm_op(1, x) #define __usdt_asm_ops2(a,x) __usdt_asm_ops1(a), __usdt_asm_op(2, x) #define __usdt_asm_ops3(a,b,x) __usdt_asm_ops2(a,b), __usdt_asm_op(3, x) #define __usdt_asm_ops4(a,b,c,x) __usdt_asm_ops3(a,b,c), __usdt_asm_op(4, x) #define __usdt_asm_ops5(a,b,c,d,x) __usdt_asm_ops4(a,b,c,d), __usdt_asm_op(5, x) #define __usdt_asm_ops6(a,b,c,d,e,x) __usdt_asm_ops5(a,b,c,d,e), __usdt_asm_op(6, x) #define __usdt_asm_ops7(a,b,c,d,e,f,x) __usdt_asm_ops6(a,b,c,d,e,f), __usdt_asm_op(7, x) #define __usdt_asm_ops8(a,b,c,d,e,f,g,x) __usdt_asm_ops7(a,b,c,d,e,f,g), __usdt_asm_op(8, x) #define __usdt_asm_ops9(a,b,c,d,e,f,g,h,x) __usdt_asm_ops8(a,b,c,d,e,f,g,h), __usdt_asm_op(9, x) #define __usdt_asm_ops10(a,b,c,d,e,f,g,h,i,x) __usdt_asm_ops9(a,b,c,d,e,f,g,h,i), __usdt_asm_op(10, x) #define __usdt_asm_ops11(a,b,c,d,e,f,g,h,i,j,x) __usdt_asm_ops10(a,b,c,d,e,f,g,h,i,j), __usdt_asm_op(11, x) #define __usdt_asm_ops12(a,b,c,d,e,f,g,h,i,j,k,x) __usdt_asm_ops11(a,b,c,d,e,f,g,h,i,j,k), __usdt_asm_op(12, x) #define __usdt_asm_ops(...) __usdt_apply(__usdt_asm_ops, __usdt_narg(__VA_ARGS__))(__VA_ARGS__) #endif /* __USDT_H */