#define TEST_MODE 0 #ifndef MAXNESTING #define MAXNESTING 10 #endif #ifndef MAXSTRINGLEN #define MAXSTRINGLEN 128 #endif #ifndef MAXACTION #define MAXACTION 1000 #endif #ifndef MAXACTION_INTERRUPTIBLE #define MAXACTION_INTERRUPTIBLE (MAXACTION * 10) #endif #ifndef MAXTRYLOCK #define MAXTRYLOCK MAXACTION #endif #ifndef TRYLOCKDELAY #define TRYLOCKDELAY 100 #endif #ifndef MAXMAPENTRIES #define MAXMAPENTRIES 2048 #endif #ifndef MAXERRORS #define MAXERRORS 0 #endif #ifndef MAXSKIPPED #define MAXSKIPPED 100 #endif #ifndef MINSTACKSPACE #define MINSTACKSPACE 1024 #endif #ifndef STP_OVERLOAD_INTERVAL #define STP_OVERLOAD_INTERVAL 1000000000LL #endif #ifndef STP_OVERLOAD_THRESHOLD #define STP_OVERLOAD_THRESHOLD 500000000LL #endif #ifndef STP_NO_OVERLOAD #define STP_OVERLOAD #endif #include "runtime.h" #include "regs.c" #include "stack.c" #include "regs-ia64.c" #include "stat.c" #include #include #include #include #include #include #include "loc2c-runtime.h" #ifndef read_trylock #define read_trylock(x) ({ read_lock(x); 1; }) #endif #if defined(CONFIG_MARKERS) #include #endif typedef char string_t[MAXSTRINGLEN]; #define STAP_SESSION_STARTING 0 #define STAP_SESSION_RUNNING 1 #define STAP_SESSION_ERROR 2 #define STAP_SESSION_STOPPING 3 #define STAP_SESSION_STOPPED 4 atomic_t session_state = ATOMIC_INIT (STAP_SESSION_STARTING); atomic_t error_count = ATOMIC_INIT (0); atomic_t skipped_count = ATOMIC_INIT (0); struct context { atomic_t busy; const char *probe_point; int actionremaining; unsigned nesting; const char *last_error; const char *last_stmt; struct pt_regs *regs; struct kretprobe_instance *pi; va_list mark_va_list; #ifdef STP_TIMING Stat *statp; #endif #ifdef STP_OVERLOAD cycles_t cycles_base; cycles_t cycles_sum; #endif union { struct probe_1493_locals { string_t argstr; union { struct { string_t __tmp0; int64_t __tmp1; int64_t __tmp2; string_t __tmp3; }; }; } probe_1493; struct function_execname_locals { string_t __retvalue; } function_execname; struct function_pid_locals { int64_t __retvalue; } function_pid; struct function_tid_locals { int64_t __retvalue; } function_tid; } locals [MAXNESTING]; }; void *contexts = NULL; /* alloc_percpu */ static void function_execname (struct context * __restrict__ c); static void function_pid (struct context * __restrict__ c); static void function_tid (struct context * __restrict__ c); void function_execname (struct context* __restrict__ c) { struct function_execname_locals * __restrict__ l = & c->locals[c->nesting].function_execname; (void) l; #define CONTEXT c #define THIS l if (0) goto out; l->__retvalue[0] = '\0'; { /* pure */ strlcpy (THIS->__retvalue, current->comm, MAXSTRINGLEN); } out: ; #undef CONTEXT #undef THIS } void function_pid (struct context* __restrict__ c) { struct function_pid_locals * __restrict__ l = & c->locals[c->nesting].function_pid; (void) l; #define CONTEXT c #define THIS l if (0) goto out; l->__retvalue = 0; { /* pure */ THIS->__retvalue = current->tgid; } out: ; #undef CONTEXT #undef THIS } void function_tid (struct context* __restrict__ c) { struct function_tid_locals * __restrict__ l = & c->locals[c->nesting].function_tid; (void) l; #define CONTEXT c #define THIS l if (0) goto out; l->__retvalue = 0; { /* pure */ THIS->__retvalue = current->pid; } out: ; #undef CONTEXT #undef THIS } #ifdef STP_TIMING static __cacheline_aligned Stat time_probe_0; #endif static void probe_1493 (struct context * __restrict__ c) { struct probe_1493_locals * __restrict__ l = & c->locals[0].probe_1493; (void) l; #ifdef STP_TIMING c->statp = & time_probe_0; #endif { unsigned numtrylock = 0; (void) numtrylock; if (0) goto unlock_; } l->argstr[0] = '\0'; { if (unlikely (c->last_error)) goto out; c->last_stmt = "identifier 'printf' at trace.stp:3:2"; c->actionremaining -= 1; if (unlikely (c->actionremaining <= 0)) { c->last_error = "MAXACTION exceeded"; goto out; } (void) ({ c->last_stmt = "identifier 'execname' at trace.stp:3:49"; strlcpy (l->__tmp0, ({ if (unlikely (c->nesting+2 >= MAXNESTING)) { c->last_error = "MAXNESTING exceeded"; c->last_stmt = "identifier 'execname' at trace.stp:3:49"; } else if (likely (! c->last_error)) { c->nesting ++; function_execname (c); c->nesting --; if (c->last_error && ! c->last_error[0]) c->last_error = 0; } c->locals[c->nesting+1].function_execname.__retvalue; }), MAXSTRINGLEN); c->last_stmt = "identifier 'pid' at trace.stp:3:61"; l->__tmp1 = ({ if (unlikely (c->nesting+2 >= MAXNESTING)) { c->last_error = "MAXNESTING exceeded"; c->last_stmt = "identifier 'pid' at trace.stp:3:61"; } else if (likely (! c->last_error)) { c->nesting ++; function_pid (c); c->nesting --; if (c->last_error && ! c->last_error[0]) c->last_error = 0; } c->locals[c->nesting+1].function_pid.__retvalue; }); c->last_stmt = "identifier 'tid' at trace.stp:3:68"; l->__tmp2 = ({ if (unlikely (c->nesting+2 >= MAXNESTING)) { c->last_error = "MAXNESTING exceeded"; c->last_stmt = "identifier 'tid' at trace.stp:3:68"; } else if (likely (! c->last_error)) { c->nesting ++; function_tid (c); c->nesting --; if (c->last_error && ! c->last_error[0]) c->last_error = 0; } c->locals[c->nesting+1].function_tid.__retvalue; }); c->last_stmt = "identifier 'argstr' at trace.stp:3:75"; strlcpy (l->__tmp3, l->argstr, MAXSTRINGLEN); if (likely (! c->last_error)) { _stp_printf ("%s (pid: %lld, tid: %lld argstr: %s ) \n", l->__tmp0, l->__tmp1, l->__tmp2, l->__tmp3); } ((int64_t)0LL); }); /* null */; } out: _stp_print_flush(); unlock_: ; } /* ---- dwarf probes ---- */ #if ! defined(CONFIG_KPROBES) #error "Need CONFIG_KPROBES!" #endif static int enter_kprobe_probe (struct kprobe *inst, struct pt_regs *regs); static int enter_kretprobe_probe (struct kretprobe_instance *inst, struct pt_regs *regs); struct stap_dwarf_probe { union { struct kprobe kp; struct kretprobe krp; } u; unsigned return_p:1; unsigned maxactive_p:1; unsigned registered_p:1; const char *module; const char *section; unsigned long address; unsigned long maxactive_val; const char *pp; void (*ph) (struct context*); } stap_dwarf_probes[] = { { .address=0x2850deUL, .module="kernel", .section="_stext", .pp="kernel.function(\"schedule@kernel/sched.c:3792\")", .ph=&probe_1493 }, }; static int enter_kprobe_probe (struct kprobe *inst, struct pt_regs *regs) { struct stap_dwarf_probe *sdp = container_of(inst, struct stap_dwarf_probe, u.kp); struct context* __restrict__ c; unsigned long flags; #if defined(STP_TIMING) || defined(STP_OVERLOAD) cycles_t cycles_atstart = get_cycles (); #endif local_irq_save (flags); if (unlikely ((((unsigned long) (& c)) & (THREAD_SIZE-1)) < (MINSTACKSPACE + sizeof (struct thread_info)))) { if (unlikely (atomic_inc_return (& skipped_count) > MAXSKIPPED)) { atomic_set (& session_state, STAP_SESSION_ERROR); _stp_exit (); } goto probe_epilogue; } if (atomic_read (&session_state) != STAP_SESSION_RUNNING) goto probe_epilogue; c = per_cpu_ptr (contexts, smp_processor_id()); if (unlikely (atomic_inc_return (&c->busy) != 1)) { if (atomic_inc_return (& skipped_count) > MAXSKIPPED) { atomic_set (& session_state, STAP_SESSION_ERROR); _stp_exit (); } atomic_dec (& c->busy); goto probe_epilogue; } c->last_error = 0; c->nesting = 0; c->regs = 0; c->pi = 0; c->probe_point = 0; c->actionremaining = MAXACTION; #ifdef STP_TIMING c->statp = 0; #endif c->probe_point = sdp->pp; c->regs = regs; (*sdp->ph) (c); #if defined(STP_TIMING) || defined(STP_OVERLOAD) { cycles_t cycles_atend = get_cycles (); int32_t cycles_elapsed = ((int32_t)cycles_atend > (int32_t)cycles_atstart) ? ((int32_t)cycles_atend - (int32_t)cycles_atstart) : (~(int32_t)0) - (int32_t)cycles_atstart + (int32_t)cycles_atend + 1; #ifdef STP_TIMING if (likely (c->statp)) _stp_stat_add(*c->statp, cycles_elapsed); #endif #ifdef STP_OVERLOAD { cycles_t interval = (cycles_atend > c->cycles_base) ? (cycles_atend - c->cycles_base) : (STP_OVERLOAD_INTERVAL + 1); c->cycles_sum += cycles_elapsed; if (interval > STP_OVERLOAD_INTERVAL) { if (c->cycles_sum > STP_OVERLOAD_THRESHOLD) { _stp_error ("probe overhead exceeded threshold"); atomic_set (&session_state, STAP_SESSION_ERROR); atomic_inc (&error_count); } c->cycles_base = cycles_atend; c->cycles_sum = 0; } } #endif } #endif if (unlikely (c->last_error && c->last_error[0])) { if (c->last_stmt != NULL) _stp_softerror ("%s near %s", c->last_error, c->last_stmt); else _stp_softerror ("%s", c->last_error); atomic_inc (& error_count); if (atomic_read (& error_count) > MAXERRORS) { atomic_set (& session_state, STAP_SESSION_ERROR); _stp_exit (); } } atomic_dec (&c->busy); probe_epilogue: local_irq_restore (flags); return 0; } static int enter_kretprobe_probe (struct kretprobe_instance *inst, struct pt_regs *regs) { struct kretprobe *krp = inst->rp; struct stap_dwarf_probe *sdp = container_of(krp, struct stap_dwarf_probe, u.krp); struct context* __restrict__ c; unsigned long flags; #if defined(STP_TIMING) || defined(STP_OVERLOAD) cycles_t cycles_atstart = get_cycles (); #endif local_irq_save (flags); if (unlikely ((((unsigned long) (& c)) & (THREAD_SIZE-1)) < (MINSTACKSPACE + sizeof (struct thread_info)))) { if (unlikely (atomic_inc_return (& skipped_count) > MAXSKIPPED)) { atomic_set (& session_state, STAP_SESSION_ERROR); _stp_exit (); } goto probe_epilogue; } if (atomic_read (&session_state) != STAP_SESSION_RUNNING) goto probe_epilogue; c = per_cpu_ptr (contexts, smp_processor_id()); if (unlikely (atomic_inc_return (&c->busy) != 1)) { if (atomic_inc_return (& skipped_count) > MAXSKIPPED) { atomic_set (& session_state, STAP_SESSION_ERROR); _stp_exit (); } atomic_dec (& c->busy); goto probe_epilogue; } c->last_error = 0; c->nesting = 0; c->regs = 0; c->pi = 0; c->probe_point = 0; c->actionremaining = MAXACTION; #ifdef STP_TIMING c->statp = 0; #endif c->probe_point = sdp->pp; c->regs = regs; c->pi = inst; (*sdp->ph) (c); #if defined(STP_TIMING) || defined(STP_OVERLOAD) { cycles_t cycles_atend = get_cycles (); int32_t cycles_elapsed = ((int32_t)cycles_atend > (int32_t)cycles_atstart) ? ((int32_t)cycles_atend - (int32_t)cycles_atstart) : (~(int32_t)0) - (int32_t)cycles_atstart + (int32_t)cycles_atend + 1; #ifdef STP_TIMING if (likely (c->statp)) _stp_stat_add(*c->statp, cycles_elapsed); #endif #ifdef STP_OVERLOAD { cycles_t interval = (cycles_atend > c->cycles_base) ? (cycles_atend - c->cycles_base) : (STP_OVERLOAD_INTERVAL + 1); c->cycles_sum += cycles_elapsed; if (interval > STP_OVERLOAD_INTERVAL) { if (c->cycles_sum > STP_OVERLOAD_THRESHOLD) { _stp_error ("probe overhead exceeded threshold"); atomic_set (&session_state, STAP_SESSION_ERROR); atomic_inc (&error_count); } c->cycles_base = cycles_atend; c->cycles_sum = 0; } } #endif } #endif if (unlikely (c->last_error && c->last_error[0])) { if (c->last_stmt != NULL) _stp_softerror ("%s near %s", c->last_error, c->last_stmt); else _stp_softerror ("%s", c->last_error); atomic_inc (& error_count); if (atomic_read (& error_count) > MAXERRORS) { atomic_set (& session_state, STAP_SESSION_ERROR); _stp_exit (); } } atomic_dec (&c->busy); probe_epilogue: local_irq_restore (flags); return 0; } int systemtap_module_init (void) { int rc = 0; int i=0, j=0; const char *probe_point = ""; down_read (& uts_sem); { #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,19) const char* machine = utsname()->machine; const char* release = utsname()->release; #else const char* machine = system_utsname.machine; const char* release = system_utsname.release; #endif if (strcmp (machine, "x86_64")) { _stp_error ("module machine mismatch (%s vs %s)", machine, "x86_64"); rc = -EINVAL; } if (strcmp (release, "2.6.22.1-rt3")) { _stp_error ("module release mismatch (%s vs %s)", release, "2.6.22.1-rt3"); rc = -EINVAL; } } up_read (& uts_sem); if (rc) goto out; (void) probe_point; (void) i; (void) j; atomic_set (&session_state, STAP_SESSION_STARTING); if (sizeof (struct context) <= 131072) contexts = alloc_percpu (struct context); if (contexts == NULL) { _stp_error ("percpu context (size %lu) allocation failed", sizeof (struct context)); rc = -ENOMEM; goto out; } #ifdef STP_TIMING time_probe_0 = _stp_stat_init (HIST_NONE); #endif for (i=0; i<1; i++) { struct stap_dwarf_probe *sdp = & stap_dwarf_probes[i]; unsigned long relocated_addr = _stp_module_relocate (sdp->module, sdp->section, sdp->address); if (relocated_addr == 0) continue; probe_point = sdp->pp; if (sdp->return_p) { sdp->u.krp.kp.addr = (void *) relocated_addr; if (sdp->maxactive_p) { sdp->u.krp.maxactive = sdp->maxactive_val; } else { sdp->u.krp.maxactive = max(10, 4*NR_CPUS); } sdp->u.krp.handler = &enter_kretprobe_probe; rc = register_kretprobe (& sdp->u.krp); } else { sdp->u.kp.addr = (void *) relocated_addr; sdp->u.kp.pre_handler = &enter_kprobe_probe; rc = register_kprobe (& sdp->u.kp); } if (rc) { for (j=i-1; j>=0; j--) { struct stap_dwarf_probe *sdp2 = & stap_dwarf_probes[j]; if (sdp2->return_p) unregister_kretprobe (&sdp2->u.krp); else unregister_kprobe (&sdp2->u.kp); } break; } else sdp->registered_p = 1; } if (rc) { _stp_error ("probe %s registration error (rc %d)", probe_point, rc); atomic_set (&session_state, STAP_SESSION_ERROR); goto out; } printk (KERN_DEBUG "%s: systemtap: 0.5.15/Red Hat elfutils 0.125, base: %p, memory: %lu+%lu+%lu+%lu+%lu data+text+ctx+io+glob, probes: 1\n", THIS_MODULE->name, THIS_MODULE->module_core, (unsigned long) (THIS_MODULE->core_size - THIS_MODULE->core_text_size), (unsigned long) THIS_MODULE->core_text_size, (unsigned long) (num_online_cpus() * sizeof(struct context)), (unsigned long) _stp_allocated_net_memory, (unsigned long) _stp_allocated_memory); atomic_set (&session_state, STAP_SESSION_RUNNING); return 0; out: return rc; } void systemtap_module_exit (void) { int holdon; int i=0, j=0; (void) i; (void) j; if (atomic_read (&session_state) == STAP_SESSION_STARTING) return; if (atomic_read (&session_state) == STAP_SESSION_RUNNING) atomic_set (&session_state, STAP_SESSION_STOPPING); do { int i; holdon = 0; for (i=0; i < NR_CPUS; i++) if (cpu_possible (i) && atomic_read (& ((struct context *)per_cpu_ptr(contexts, i))->busy)) holdon = 1; cpu_relax (); } while (holdon); for (i=0; i<1; i++) { struct stap_dwarf_probe *sdp = & stap_dwarf_probes[i]; if (! sdp->registered_p) continue; if (sdp->return_p) { unregister_kretprobe (&sdp->u.krp); atomic_add (sdp->u.krp.nmissed, & skipped_count); atomic_add (sdp->u.krp.kp.nmissed, & skipped_count); } else { unregister_kprobe (&sdp->u.kp); atomic_add (sdp->u.kp.nmissed, & skipped_count); } sdp->registered_p = 0; } free_percpu (contexts); #ifdef STP_TIMING { if (likely (time_probe_0)) { const char *probe_point = "kernel.function(\"schedule\")"; const char *decl_location = "trace.stp:1:1"; struct stat_data *stats = _stp_stat_get (time_probe_0, 0); const char *error; if (stats->count) { int64_t avg = _stp_div64 (&error, stats->sum, stats->count); _stp_printf ("probe %s (%s), hits: %lld, cycles: %lldmin/%lldavg/%lldmax\n", probe_point, decl_location, (long long) stats->count, (long long) stats->min, (long long) avg, (long long) stats->max); } } _stp_print_flush(); } #endif if (atomic_read (& skipped_count) || atomic_read (& error_count)) { _stp_printf ("WARNING: Number of errors: %d, skipped probes: %d\n", (int) atomic_read (& error_count), (int) atomic_read (& skipped_count)); _stp_print_flush(); } } int probe_start () { return systemtap_module_init () ? -1 : 0; } void probe_exit () { systemtap_module_exit (); } MODULE_DESCRIPTION("systemtap probe"); MODULE_LICENSE("GPL"); /* filled in by runtime */ struct stap_symbol *stap_symbols; unsigned stap_num_symbols;