include/sys/fasttrap_impl.h

   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 (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #ifndef _FASTTRAP_IMPL_H
  28 #define _FASTTRAP_IMPL_H
  29
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31
  32 #include <sys/types.h>
  33 #include <sys/dtrace.h>
  34 #include <sys/proc.h>
  35 #include <sys/fasttrap.h>
  36 #include <sys/fasttrap_isa.h>
  37
  38 #ifdef  __cplusplus
  39 extern "C" {
  40 #endif
  41
  42 /*
  43  * Fasttrap Providers, Probes and Tracepoints
  44  *
  45  * Each Solaris process can have multiple providers -- the pid provider as
  46  * well as any number of user-level statically defined tracing (USDT)
  47  * providers. Those providers are each represented by a fasttrap_provider_t.
  48  * All providers for a given process have a pointer to a shared
  49  * fasttrap_proc_t. The fasttrap_proc_t has two states: active or defunct.
  50  * When the count of active providers goes to zero it becomes defunct; a
  51  * provider drops its active count when it is removed individually or as part
  52  * of a mass removal when a process exits or performs an exec.
  53  *
  54  * Each probe is represented by a fasttrap_probe_t which has a pointer to
  55  * its associated provider as well as a list of fasttrap_id_tp_t structures
  56  * which are tuples combining a fasttrap_id_t and a fasttrap_tracepoint_t.
  57  * A fasttrap_tracepoint_t represents the actual point of instrumentation
  58  * and it contains two lists of fasttrap_id_t structures (to be fired pre-
  59  * and post-instruction emulation) that identify the probes attached to the
  60  * tracepoint. Tracepoints also have a pointer to the fasttrap_proc_t for the
  61  * process they trace which is used when looking up a tracepoint both when a
  62  * probe fires and when enabling and disabling probes.
  63  *
  64  * It's important to note that probes are preallocated with the necessary
  65  * number of tracepoints, but that tracepoints can be shared by probes and
  66  * swapped between probes. If a probe's preallocated tracepoint is enabled
  67  * (and, therefore, the associated probe is enabled), and that probe is
  68  * then disabled, ownership of that tracepoint may be exchanged for an
  69  * unused tracepoint belonging to another probe that was attached to the
  70  * enabled tracepoint.
  71  */
  72
  73 typedef struct fasttrap_proc {
  74         pid_t ftpc_pid;                         /* process ID for this proc */
  75         uint64_t ftpc_acount;                   /* count of active providers */
  76         uint64_t ftpc_rcount;                   /* count of extant providers */
  77         kmutex_t ftpc_mtx;                      /* lock on all but acount */
  78         struct fasttrap_proc *ftpc_next;        /* next proc in hash chain */
  79 } fasttrap_proc_t;
  80
  81 typedef struct fasttrap_provider {
  82         pid_t ftp_pid;                          /* process ID for this prov */
  83         char ftp_name[DTRACE_PROVNAMELEN];      /* prov name (w/o the pid) */
  84         dtrace_provider_id_t ftp_provid;        /* DTrace provider handle */
  85         uint_t ftp_marked;                      /* mark for possible removal */
  86         uint_t ftp_retired;                     /* mark when retired */
  87         kmutex_t ftp_mtx;                       /* provider lock */
  88         kmutex_t ftp_cmtx;                      /* lock on creating probes */
  89         uint64_t ftp_rcount;                    /* enabled probes ref count */
  90         uint64_t ftp_ccount;                    /* consumers creating probes */
  91         uint64_t ftp_mcount;                    /* meta provider count */
  92         fasttrap_proc_t *ftp_proc;              /* shared proc for all provs */
  93         struct fasttrap_provider *ftp_next;     /* next prov in hash chain */
  94 } fasttrap_provider_t;
  95
  96 typedef struct fasttrap_id fasttrap_id_t;
  97 typedef struct fasttrap_probe fasttrap_probe_t;
  98 typedef struct fasttrap_tracepoint fasttrap_tracepoint_t;
  99
 100 struct fasttrap_id {
 101         fasttrap_probe_t *fti_probe;            /* referrring probe */
 102         fasttrap_id_t *fti_next;                /* enabled probe list on tp */
 103         fasttrap_probe_type_t fti_ptype;        /* probe type */
 104 };
 105
 106 typedef struct fasttrap_id_tp {
 107         fasttrap_id_t fit_id;
 108         fasttrap_tracepoint_t *fit_tp;
 109 } fasttrap_id_tp_t;
 110
 111 struct fasttrap_probe {
 112         dtrace_id_t ftp_id;                     /* DTrace probe identifier */
 113         pid_t ftp_pid;                          /* pid for this probe */
 114         fasttrap_provider_t *ftp_prov;          /* this probe's provider */
 115         uintptr_t ftp_faddr;                    /* associated function's addr */
 116         size_t ftp_fsize;                       /* associated function's size */
 117         uint64_t ftp_gen;                       /* modification generation */
 118         uint64_t ftp_ntps;                      /* number of tracepoints */
 119         uint8_t *ftp_argmap;                    /* native to translated args */
 120         uint8_t ftp_nargs;                      /* translated argument count */
 121         uint8_t ftp_enabled;                    /* is this probe enabled */
 122         char *ftp_xtypes;                       /* translated types index */
 123         char *ftp_ntypes;                       /* native types index */
 124         fasttrap_id_tp_t ftp_tps[1];            /* flexible array */
 125 };
 126
 127 #define FASTTRAP_ID_INDEX(id)   \
 128 ((fasttrap_id_tp_t *)(((char *)(id) - offsetof(fasttrap_id_tp_t, fit_id))) - \
 129 &(id)->fti_probe->ftp_tps[0])
 130
 131 struct fasttrap_tracepoint {
 132         fasttrap_proc_t *ftt_proc;              /* associated process struct */
 133         uintptr_t ftt_pc;                       /* address of tracepoint */
 134         pid_t ftt_pid;                          /* pid of tracepoint */
 135         fasttrap_machtp_t ftt_mtp;              /* ISA-specific portion */
 136         fasttrap_id_t *ftt_ids;                 /* NULL-terminated list */
 137         fasttrap_id_t *ftt_retids;              /* NULL-terminated list */
 138         fasttrap_tracepoint_t *ftt_next;        /* link in global hash */
 139 };
 140
 141 typedef struct fasttrap_bucket {
 142         kmutex_t ftb_mtx;                       /* bucket lock */
 143         void *ftb_data;                         /* data payload */
 144
 145         uint8_t ftb_pad[64 - sizeof (kmutex_t) - sizeof (void *)];
 146 } fasttrap_bucket_t;
 147
 148 typedef struct fasttrap_hash {
 149         ulong_t fth_nent;                       /* power-of-2 num. of entries */
 150         ulong_t fth_mask;                       /* fth_nent - 1 */
 151         fasttrap_bucket_t *fth_table;           /* array of buckets */
 152 } fasttrap_hash_t;
 153
 154 /*
 155  * If at some future point these assembly functions become observable by
 156  * DTrace, then these defines should become separate functions so that the
 157  * fasttrap provider doesn't trigger probes during internal operations.
 158  */
 159 #define fasttrap_copyout        copyout
 160 #define fasttrap_fuword32       fuword32
 161 #define fasttrap_suword32       suword32
 162
 163 #define fasttrap_fulword        fulword
 164 #define fasttrap_sulword        sulword
 165
 166 extern void fasttrap_sigtrap(proc_t *, kthread_t *, uintptr_t);
 167
 168 extern dtrace_id_t              fasttrap_probe_id;
 169 extern fasttrap_hash_t          fasttrap_tpoints;
 170
 171 #define FASTTRAP_TPOINTS_INDEX(pid, pc) \
 172         (((pc) / sizeof (fasttrap_instr_t) + (pid)) & fasttrap_tpoints.fth_mask)
 173
 174 /*
 175  * Must be implemented by fasttrap_isa.c
 176  */
 177 extern int fasttrap_tracepoint_init(proc_t *, fasttrap_tracepoint_t *,
 178     uintptr_t, fasttrap_probe_type_t);
 179 extern int fasttrap_tracepoint_install(proc_t *, fasttrap_tracepoint_t *);
 180 extern int fasttrap_tracepoint_remove(proc_t *, fasttrap_tracepoint_t *);
 181
 182 extern int fasttrap_pid_probe(struct regs *);
 183 extern int fasttrap_return_probe(struct regs *);
 184
 185 extern uint64_t fasttrap_pid_getarg(void *, dtrace_id_t, void *, int, int);
 186 extern uint64_t fasttrap_usdt_getarg(void *, dtrace_id_t, void *, int, int);
 187
 188 #ifdef  __cplusplus
 189 }
 190 #endif
 191
 192 #endif  /* _FASTTRAP_IMPL_H */