libdtrace/common/dt_handle.c

	dt_handle.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <stddef.h>
#include <stdlib.h>
#include <strings.h>
#include <errno.h>
#include <unistd.h>
#include <dt_impl.h>
#include <assert.h>
#include <alloca.h>

static const char _dt_errprog[] =
"dtrace:::ERROR"
"{"
"   trace(arg1);"
"   trace(arg2);"
"   trace(arg3);"
"   trace(arg4);"
"   trace(arg5);"
"}";

int
dtrace_handle_err(dtrace_hdl_t *dtp, dtrace_handle_err_f *hdlr, void *arg)
{
    dtrace_prog_t *pgp = NULL;
    dt_stmt_t *stp;
    dtrace_ecbdesc_t *edp;

    /*
     * We don't currently support multiple error handlers.
     */
    if (dtp->dt_errhdlr != NULL)
        return (dt_set_errno(dtp, EALREADY));

    /*
     * If the DTRACEOPT_GRABANON is enabled, the anonymous enabling will
     * already have a dtrace:::ERROR probe enabled; save 'hdlr' and 'arg'
     * but do not bother compiling and enabling _dt_errprog.
     */
    if (dtp->dt_options[DTRACEOPT_GRABANON] != DTRACEOPT_UNSET)
        goto out;

    if ((pgp = dtrace_program_strcompile(dtp, _dt_errprog,
        DTRACE_PROBESPEC_NAME, DTRACE_C_ZDEFS, 0, NULL)) == NULL)
        return (dt_set_errno(dtp, dtrace_errno(dtp)));

    stp = dt_list_next(&pgp->dp_stmts);
    assert(stp != NULL);

    edp = stp->ds_desc->dtsd_ecbdesc;
    assert(edp != NULL);
    edp->dted_uarg = DT_ECB_ERROR;

out:
    dtp->dt_errhdlr = hdlr;
    dtp->dt_errarg = arg;
    dtp->dt_errprog = pgp;

    return (0);
}

int
dtrace_handle_drop(dtrace_hdl_t *dtp, dtrace_handle_drop_f *hdlr, void *arg)
{
    if (dtp->dt_drophdlr != NULL)
        return (dt_set_errno(dtp, EALREADY));

    dtp->dt_drophdlr = hdlr;
    dtp->dt_droparg = arg;

    return (0);
}

int
dtrace_handle_proc(dtrace_hdl_t *dtp, dtrace_handle_proc_f *hdlr, void *arg)
{
    if (dtp->dt_prochdlr != NULL)
        return (dt_set_errno(dtp, EALREADY));

    dtp->dt_prochdlr = hdlr;
    dtp->dt_procarg = arg;

    return (0);
}

int
dtrace_handle_buffered(dtrace_hdl_t *dtp, dtrace_handle_buffered_f *hdlr,
    void *arg)
{
    if (dtp->dt_bufhdlr != NULL)
        return (dt_set_errno(dtp, EALREADY));

    if (hdlr == NULL)
        return (dt_set_errno(dtp, EINVAL));

    dtp->dt_bufhdlr = hdlr;
    dtp->dt_bufarg = arg;

    return (0);
}

#define DT_REC(type, ndx) *((type *)((uintptr_t)data->dtpda_data + \
    epd->dtepd_rec[(ndx)].dtrd_offset))

static int
dt_handle_err(dtrace_hdl_t *dtp, dtrace_probedata_t *data)
{
    dtrace_eprobedesc_t *epd = data->dtpda_edesc, *errepd;
    dtrace_probedesc_t *pd = data->dtpda_pdesc, *errpd;
    dtrace_errdata_t err;
    dtrace_epid_t epid;

    char where[30];
    char details[30];
    char offinfo[30];
    const int slop = 80;
    const char *faultstr;
    char *str;
    int len;

    assert(epd->dtepd_uarg == DT_ECB_ERROR);

    if (epd->dtepd_nrecs != 5 || strcmp(pd->dtpd_provider, "dtrace") != 0 ||
        strcmp(pd->dtpd_name, "ERROR") != 0)
        return (dt_set_errno(dtp, EDT_BADERROR));

    /*
     * This is an error.  We have the following items here:  EPID,
     * faulting action, DIF offset, fault code and faulting address.
     */
    epid = (uint32_t)DT_REC(uint64_t, 0);

    if (dt_epid_lookup(dtp, epid, &errepd, &errpd) != 0)
        return (dt_set_errno(dtp, EDT_BADERROR));

    err.dteda_edesc = errepd;
    err.dteda_pdesc = errpd;
    err.dteda_cpu = data->dtpda_cpu;
    err.dteda_action = (int)DT_REC(uint64_t, 1);
    err.dteda_offset = (int)DT_REC(uint64_t, 2);
    err.dteda_fault = (int)DT_REC(uint64_t, 3);
    err.dteda_addr = DT_REC(uint64_t, 4);

    faultstr = dtrace_faultstr(dtp, err.dteda_fault);
    len = sizeof (where) + sizeof (offinfo) + strlen(faultstr) +
        strlen(errpd->dtpd_provider) + strlen(errpd->dtpd_mod) +
        strlen(errpd->dtpd_name) + strlen(errpd->dtpd_func) +
        slop;

    str = (char *)alloca(len);

    if (err.dteda_action == 0) {
        (void) sprintf(where, "predicate");
    } else {
        (void) sprintf(where, "action #%d", err.dteda_action);
    }

    if (err.dteda_offset != -1) {
        (void) sprintf(offinfo, " at DIF offset %d", err.dteda_offset);
    } else {
        offinfo[0] = 0;
    }

    switch (err.dteda_fault) {
    case DTRACEFLT_BADADDR:
    case DTRACEFLT_BADALIGN:
        (void) sprintf(details, " (0x%llx)",
            (u_longlong_t)err.dteda_addr);
        break;

    default:
        details[0] = 0;
    }

    (void) snprintf(str, len, "error on enabled probe ID %u "
        "(ID %u: %s:%s:%s:%s): %s%s in %s%s\n",
        epid, errpd->dtpd_id, errpd->dtpd_provider,
        errpd->dtpd_mod, errpd->dtpd_func,
        errpd->dtpd_name, dtrace_faultstr(dtp, err.dteda_fault),
        details, where, offinfo);

    err.dteda_msg = str;

    if (dtp->dt_errhdlr == NULL)
        return (dt_set_errno(dtp, EDT_ERRABORT));

    if ((*dtp->dt_errhdlr)(&err, dtp->dt_errarg) == DTRACE_HANDLE_ABORT)
        return (dt_set_errno(dtp, EDT_ERRABORT));

    return (0);
}

int
dt_handle_liberr(dtrace_hdl_t *dtp, const dtrace_probedata_t *data,
    const char *faultstr)
{
    dtrace_probedesc_t *errpd = data->dtpda_pdesc;
    dtrace_errdata_t err;
    const int slop = 80;
    char *str;
    int len;

    err.dteda_edesc = data->dtpda_edesc;
    err.dteda_pdesc = errpd;
    err.dteda_cpu = data->dtpda_cpu;
    err.dteda_action = -1;
    err.dteda_offset = -1;
    err.dteda_fault = DTRACEFLT_LIBRARY;
    err.dteda_addr = NULL;

    len = strlen(faultstr) +
        strlen(errpd->dtpd_provider) + strlen(errpd->dtpd_mod) +
        strlen(errpd->dtpd_name) + strlen(errpd->dtpd_func) +
        slop;

    str = alloca(len);

    (void) snprintf(str, len, "error on enabled probe ID %u "
        "(ID %u: %s:%s:%s:%s): %s\n",
        data->dtpda_edesc->dtepd_epid,
        errpd->dtpd_id, errpd->dtpd_provider,
        errpd->dtpd_mod, errpd->dtpd_func,
        errpd->dtpd_name, faultstr);

    err.dteda_msg = str;

    if (dtp->dt_errhdlr == NULL)
        return (dt_set_errno(dtp, EDT_ERRABORT));

    if ((*dtp->dt_errhdlr)(&err, dtp->dt_errarg) == DTRACE_HANDLE_ABORT)
        return (dt_set_errno(dtp, EDT_ERRABORT));

    return (0);
}

int
dt_handle_cpudrop(dtrace_hdl_t *dtp, processorid_t cpu,
    dtrace_dropkind_t what, uint64_t howmany)
{
    dtrace_dropdata_t drop;
    char str[80];

    assert(what == DTRACEDROP_PRINCIPAL || what == DTRACEDROP_AGGREGATION);

    bzero(&drop, sizeof (drop));
    drop.dtdda_handle = dtp;
    drop.dtdda_cpu = cpu;
    drop.dtdda_kind = what;
    drop.dtdda_drops = howmany;
    drop.dtdda_msg = str;

    (void) snprintf(str, sizeof (str), "%llu %sdrop%s on CPU %d\n",
        howmany, what == DTRACEDROP_PRINCIPAL ? "" : "aggregation ",
        howmany > 1 ? "s" : "", cpu);

    if (dtp->dt_drophdlr == NULL)
        return (dt_set_errno(dtp, EDT_DROPABORT));

    if ((*dtp->dt_drophdlr)(&drop, dtp->dt_droparg) == DTRACE_HANDLE_ABORT)
        return (dt_set_errno(dtp, EDT_DROPABORT));

    return (0);
}

static const struct {
    dtrace_dropkind_t dtdrt_kind;
    uintptr_t dtdrt_offset;
    const char *dtdrt_str;
    const char *dtdrt_msg;
} _dt_droptab[] = {
    { DTRACEDROP_DYNAMIC,
        offsetof(dtrace_status_t, dtst_dyndrops),
        "dynamic variable drop" },

    { DTRACEDROP_DYNRINSE,
        offsetof(dtrace_status_t, dtst_dyndrops_rinsing),
        "dynamic variable drop", " with non-empty rinsing list" },

    { DTRACEDROP_DYNDIRTY,
        offsetof(dtrace_status_t, dtst_dyndrops_dirty),
        "dynamic variable drop", " with non-empty dirty list" },

    { DTRACEDROP_SPEC,
        offsetof(dtrace_status_t, dtst_specdrops),
        "speculative drop" },

    { DTRACEDROP_SPECBUSY,
        offsetof(dtrace_status_t, dtst_specdrops_busy),
        "failed speculation", " (available buffer(s) still busy)" },

    { DTRACEDROP_SPECUNAVAIL,
        offsetof(dtrace_status_t, dtst_specdrops_unavail),
        "failed speculation", " (no speculative buffer available)" },

    { 0, 0, NULL }
};

int
dt_handle_status(dtrace_hdl_t *dtp, dtrace_status_t *old, dtrace_status_t *new)
{
    dtrace_dropdata_t drop;
    char str[80];
    uintptr_t base = (uintptr_t)new, obase = (uintptr_t)old;
    int i;

    bzero(&drop, sizeof (drop));
    drop.dtdda_handle = dtp;
    drop.dtdda_cpu = DTRACE_CPUALL;
    drop.dtdda_msg = str;

    /*
     * First, check to see if we've been killed -- in which case we abort.
     */
    if (new->dtst_killed && !old->dtst_killed)
        return (dt_set_errno(dtp, EDT_BRICKED));

    for (i = 0; _dt_droptab[i].dtdrt_str != NULL; i++) {
        uintptr_t naddr = base + _dt_droptab[i].dtdrt_offset;
        uintptr_t oaddr = obase + _dt_droptab[i].dtdrt_offset;

        uint64_t nval = *((uint64_t *)naddr);
        uint64_t oval = *((uint64_t *)oaddr);

        if (nval == oval)
            continue;

        (void) snprintf(str, sizeof (str), "%llu %s%s%s\n", nval - oval,
            _dt_droptab[i].dtdrt_str, (nval - oval > 1) ? "s" : "",
            _dt_droptab[i].dtdrt_msg != NULL ?
            _dt_droptab[i].dtdrt_msg : "");

        drop.dtdda_kind = _dt_droptab[i].dtdrt_kind;
        drop.dtdda_total = nval;
        drop.dtdda_drops = nval - oval;

        if (dtp->dt_drophdlr == NULL)
            return (dt_set_errno(dtp, EDT_DROPABORT));

        if ((*dtp->dt_drophdlr)(&drop,
            dtp->dt_droparg) == DTRACE_HANDLE_ABORT)
            return (dt_set_errno(dtp, EDT_DROPABORT));
    }

    return (0);
}

int
dt_handle(dtrace_hdl_t *dtp, dtrace_probedata_t *data)
{
    dtrace_eprobedesc_t *epd = data->dtpda_edesc;
    int rval;

    switch (epd->dtepd_uarg) {
    case DT_ECB_ERROR:
        rval = dt_handle_err(dtp, data);
        break;

    default:
        return (DTRACE_CONSUME_THIS);
    }

    if (rval == 0)
        return (DTRACE_CONSUME_NEXT);

    return (DTRACE_CONSUME_ERROR);
}