dtrace_subr.c revision 1.1
1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 * 22 * $FreeBSD$ 23 * 24 */ 25/* 26 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 27 * Use is subject to license terms. 28 */ 29 30#include <sys/cdefs.h> 31__FBSDID("$FreeBSD$"); 32 33#include <sys/param.h> 34#include <sys/systm.h> 35#include <sys/types.h> 36#include <sys/kernel.h> 37#include <sys/malloc.h> 38#include <sys/kmem.h> 39#include <sys/xcall.h> 40#include <sys/cpu.h> 41#include <sys/dtrace_impl.h> 42#include <sys/dtrace_bsd.h> 43#include <machine/regnum.h> 44#include <machine/locore.h> 45#include <machine/trap.h> 46 47#define DELAYBRANCH(x) ((int)(x) < 0) 48 49#ifdef __FreeBSD__ 50#define CURRENT_CPU curcpu 51#endif 52#ifdef __NetBSD__ 53#define CURRENT_CPU cpu_index(curcpu()) 54#endif 55 56extern dtrace_id_t dtrace_probeid_error; 57extern int (*dtrace_invop_jump_addr)(struct trapframe *); 58extern void dtrace_getnanotime(struct timespec *tsp); 59 60int dtrace_invop(uintptr_t, struct trapframe *, uintptr_t); 61void dtrace_invop_init(void); 62void dtrace_invop_uninit(void); 63 64void dtrace_gethrtime_init(void); 65 66typedef struct dtrace_invop_hdlr { 67 int (*dtih_func)(uintptr_t, struct trapframe *, uintptr_t); 68 struct dtrace_invop_hdlr *dtih_next; 69} dtrace_invop_hdlr_t; 70 71dtrace_invop_hdlr_t *dtrace_invop_hdlr; 72 73int 74dtrace_invop(uintptr_t addr, struct trapframe *stack, uintptr_t eax) 75{ 76 dtrace_invop_hdlr_t *hdlr; 77 int rval; 78 79 for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next) 80 if ((rval = hdlr->dtih_func(addr, stack, eax)) != 0) 81 return (rval); 82 83 return (0); 84} 85 86void 87dtrace_invop_add(int (*func)(uintptr_t, struct trapframe *, uintptr_t)) 88{ 89 dtrace_invop_hdlr_t *hdlr; 90 91 hdlr = kmem_alloc(sizeof (dtrace_invop_hdlr_t), KM_SLEEP); 92 hdlr->dtih_func = func; 93 hdlr->dtih_next = dtrace_invop_hdlr; 94 dtrace_invop_hdlr = hdlr; 95} 96 97void 98dtrace_invop_remove(int (*func)(uintptr_t, struct trapframe *, uintptr_t)) 99{ 100 dtrace_invop_hdlr_t *hdlr, *prev; 101 102 hdlr = dtrace_invop_hdlr; 103 prev = NULL; 104 105 for (;;) { 106 if (hdlr == NULL) 107 panic("attempt to remove non-existent invop handler"); 108 109 if (hdlr->dtih_func == func) 110 break; 111 112 prev = hdlr; 113 hdlr = hdlr->dtih_next; 114 } 115 116 if (prev == NULL) { 117 ASSERT(dtrace_invop_hdlr == hdlr); 118 dtrace_invop_hdlr = hdlr->dtih_next; 119 } else { 120 ASSERT(dtrace_invop_hdlr != hdlr); 121 prev->dtih_next = hdlr->dtih_next; 122 } 123 124 kmem_free(hdlr, 0); 125} 126 127/*ARGSUSED*/ 128void 129dtrace_toxic_ranges(void (*func)(uintptr_t base, uintptr_t limit)) 130{ 131 /* XXXXXXsimonb what is a "toxic range"? */ 132} 133 134static void 135xcall_func(void *arg0, void *arg1) 136{ 137 dtrace_xcall_t func = arg0; 138 139 (*func)(arg1); 140} 141 142void 143dtrace_xcall(processorid_t cpu, dtrace_xcall_t func, void *arg) 144{ 145 uint64_t where; 146 147 if (cpu == DTRACE_CPUALL) { 148 where = xc_broadcast(0, xcall_func, func, arg); 149 } else { 150 struct cpu_info *ci = cpu_lookup(cpu); 151 152 KASSERT(ci != NULL); 153 where = xc_unicast(0, xcall_func, func, arg, ci); 154 } 155 xc_wait(where); 156} 157 158static void 159dtrace_sync_func(void) 160{ 161 162} 163 164void 165dtrace_sync(void) 166{ 167 168 dtrace_xcall(DTRACE_CPUALL, (dtrace_xcall_t)dtrace_sync_func, NULL); 169} 170 171/* 172 * DTrace needs a high resolution time function which can 173 * be called from a probe context and guaranteed not to have 174 * instrumented with probes itself. 175 * 176 * Returns nanoseconds since boot. 177 */ 178uint64_t 179dtrace_gethrtime() 180{ 181 struct timespec curtime; 182 183 nanouptime(&curtime); 184 185 return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec); 186 187} 188 189void 190dtrace_gethrtime_init(void) 191{ 192} 193 194uint64_t 195dtrace_gethrestime(void) 196{ 197 struct timespec current_time; 198 199 dtrace_getnanotime(¤t_time); 200 201 return (current_time.tv_sec * 1000000000UL + current_time.tv_nsec); 202} 203 204/* Function to handle DTrace traps during probes. See amd64/amd64/trap.c */ 205int 206dtrace_trap(struct trapframe *frame, u_int type) 207{ 208 /* 209 * A trap can occur while DTrace executes a probe. Before 210 * executing the probe, DTrace blocks re-scheduling and sets 211 * a flag in its per-cpu flags to indicate that it doesn't 212 * want to fault. On returning from the probe, the no-fault 213 * flag is cleared and finally re-scheduling is enabled. 214 * 215 * Check if DTrace has enabled 'no-fault' mode: 216 */ 217 218 if ((cpu_core[CURRENT_CPU].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) { 219 /* 220 * There are only a couple of trap types that are expected. 221 * All the rest will be handled in the usual way. 222 */ 223 switch (type) { 224 /* Page fault. */ 225 case T_TLB_ST_MISS: 226 case T_ADDR_ERR_ST: 227 case T_TLB_LD_MISS: 228 case T_ADDR_ERR_LD: 229 case T_BUS_ERR_IFETCH: 230 /* Flag a bad address. */ 231 cpu_core[CURRENT_CPU].cpuc_dtrace_flags |= CPU_DTRACE_BADADDR; 232 cpu_core[CURRENT_CPU].cpuc_dtrace_illval = frame->tf_regs[_R_BADVADDR]; 233 234 /* 235 * Offset the instruction pointer to the instruction 236 * following the one causing the fault. 237 */ 238 if (DELAYBRANCH(frame->tf_regs[_R_CAUSE])) /* Check BD bit */ 239 { 240 /* XXX: check MipsEmulateBranch on MIPS64 241 frame->tf_regs[_R_PC] = MipsEmulateBranch(frame, 242 frame->tf_regs[_R_PC], 0, 0); 243 */ 244 panic("%s: delay slot at %jx, badvaddr = %jx\n", 245 __func__, (intmax_t)frame->tf_regs[_R_PC], 246 (intmax_t)frame->tf_regs[_R_BADVADDR]); 247 } 248 else 249 frame->tf_regs[_R_PC] += sizeof(int); 250 return (1); 251 default: 252 /* Handle all other traps in the usual way. */ 253 break; 254 } 255 } 256 257 /* Handle the trap in the usual way. */ 258 return (0); 259} 260 261void 262dtrace_probe_error(dtrace_state_t *state, dtrace_epid_t epid, int which, 263 int fault, int fltoffs, uintptr_t illval) 264{ 265 266 dtrace_probe(dtrace_probeid_error, (uint64_t)(uintptr_t)state, 267 (uintptr_t)epid, 268 (uintptr_t)which, (uintptr_t)fault, (uintptr_t)fltoffs); 269} 270 271static int 272dtrace_invop_start(struct trapframe *frame) 273{ 274 register_t *sp; 275 int16_t offs; 276 int invop; 277 278 invop = dtrace_invop(frame->tf_regs[_R_PC], frame, frame->tf_regs[_R_PC]); 279 if (invop == 0) 280 return (-1); 281 282 offs = (invop & LDSD_DATA_MASK); 283 sp = (register_t *)(intptr_t)(frame->tf_regs[_R_SP] + offs); 284 285 switch (invop & LDSD_RA_SP_MASK) { 286 case LD_RA_SP: 287 frame->tf_regs[_R_RA] = *sp; 288 frame->tf_regs[_R_PC] += INSN_SIZE; 289 break; 290 case SD_RA_SP: 291 *(sp) = frame->tf_regs[_R_RA]; 292 frame->tf_regs[_R_PC] += INSN_SIZE; 293 break; 294 default: 295 printf("%s: 0x%x undefined\n", __func__, invop); 296 return (-1); 297 }; 298 299 return (0); 300} 301 302void 303dtrace_invop_init(void) 304{ 305 306 dtrace_invop_jump_addr = dtrace_invop_start; 307} 308 309void 310dtrace_invop_uninit(void) 311{ 312 313 dtrace_invop_jump_addr = 0; 314} 315