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4474 DTrace Userland CTF Support
4475 DTrace userland Keyword
4476 DTrace tests should be better citizens
4479 pid provider types
4480 dof emulation missing checks
Reviewed by: Bryan Cantrill <bryan@joyent.com>
@@ -20,10 +20,13 @@
*/
/*
* Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
*/
+/*
+ * Copyright (c) 2013, Joyent, Inc. All rights reserved.
+ */
#include <sys/types.h>
#include <sys/modctl.h>
#include <sys/kobj.h>
#include <sys/kobj_impl.h>
@@ -416,10 +419,13 @@
};
dt_module_t *
dt_module_create(dtrace_hdl_t *dtp, const char *name)
{
+ long pid;
+ char *eptr;
+ dt_ident_t *idp;
uint_t h = dt_strtab_hash(name, NULL) % dtp->dt_modbuckets;
dt_module_t *dmp;
for (dmp = dtp->dt_mods[h]; dmp != NULL; dmp = dmp->dm_next) {
if (strcmp(dmp->dm_name, name) == 0)
@@ -439,10 +445,36 @@
if (dtp->dt_conf.dtc_ctfmodel == CTF_MODEL_LP64)
dmp->dm_ops = &dt_modops_64;
else
dmp->dm_ops = &dt_modops_32;
+ /*
+ * Modules for userland processes are special. They always refer to a
+ * specific process and have a copy of their CTF data from a specific
+ * instant in time. Any dt_module_t that begins with 'pid' is a module
+ * for a specific process, much like how any probe description that
+ * begins with 'pid' is special. pid123 refers to process 123. A module
+ * that is just 'pid' refers specifically to pid$target. This is
+ * generally done as D does not currently allow for macros to be
+ * evaluated when working with types.
+ */
+ if (strncmp(dmp->dm_name, "pid", 3) == 0) {
+ errno = 0;
+ if (dmp->dm_name[3] == '\0') {
+ idp = dt_idhash_lookup(dtp->dt_macros, "target");
+ if (idp != NULL && idp->di_id != 0)
+ dmp->dm_pid = idp->di_id;
+ } else {
+ pid = strtol(dmp->dm_name + 3, &eptr, 10);
+ if (errno == 0 && *eptr == '\0')
+ dmp->dm_pid = (pid_t)pid;
+ else
+ dt_dprintf("encountered malformed pid "
+ "module: %s\n", dmp->dm_name);
+ }
+ }
+
return (dmp);
}
dt_module_t *
dt_module_lookup_by_name(dtrace_hdl_t *dtp, const char *name)
@@ -502,16 +534,173 @@
dmp->dm_name, ctsp->cts_name, (ulong_t)ctsp->cts_size);
return (0);
}
+typedef struct dt_module_cb_arg {
+ struct ps_prochandle *dpa_proc;
+ dtrace_hdl_t *dpa_dtp;
+ dt_module_t *dpa_dmp;
+ uint_t dpa_count;
+} dt_module_cb_arg_t;
+
+/* ARGSUSED */
+static int
+dt_module_load_proc_count(void *arg, const prmap_t *prmap, const char *obj)
+{
+ ctf_file_t *fp;
+ dt_module_cb_arg_t *dcp = arg;
+
+ /* Try to grab a ctf container if it exists */
+ fp = Pname_to_ctf(dcp->dpa_proc, obj);
+ if (fp != NULL)
+ dcp->dpa_count++;
+ return (0);
+}
+
+/* ARGSUSED */
+static int
+dt_module_load_proc_build(void *arg, const prmap_t *prmap, const char *obj)
+{
+ ctf_file_t *fp;
+ char buf[MAXPATHLEN], *p;
+ dt_module_cb_arg_t *dcp = arg;
+ int count = dcp->dpa_count;
+ Lmid_t lmid;
+
+ fp = Pname_to_ctf(dcp->dpa_proc, obj);
+ if (fp == NULL)
+ return (0);
+ fp = ctf_dup(fp);
+ if (fp == NULL)
+ return (0);
+ dcp->dpa_dmp->dm_libctfp[count] = fp;
+ /*
+ * While it'd be nice to simply use objname here, because of our prior
+ * actions we'll always get a resolved object name to its on disk file.
+ * Like the pid provider, we need to tell a bit of a lie here. The type
+ * that the user thinks of is in terms of the libraries they requested,
+ * eg. libc.so.1, they don't care about the fact that it's
+ * libc_hwcap.so.1.
+ */
+ (void) Pobjname(dcp->dpa_proc, prmap->pr_vaddr, buf, sizeof (buf));
+ if ((p = strrchr(buf, '/')) == NULL)
+ p = buf;
+ else
+ p++;
+
+ /*
+ * If for some reason we can't find a link map id for this module, which
+ * would be really quite weird. We instead just say the link map id is
+ * zero.
+ */
+ if (Plmid(dcp->dpa_proc, prmap->pr_vaddr, &lmid) != 0)
+ lmid = 0;
+
+ if (lmid == 0)
+ dcp->dpa_dmp->dm_libctfn[count] = strdup(p);
+ else
+ (void) asprintf(&dcp->dpa_dmp->dm_libctfn[count],
+ "LM%lx`%s", lmid, p);
+ if (dcp->dpa_dmp->dm_libctfn[count] == NULL)
+ return (1);
+ ctf_setspecific(fp, dcp->dpa_dmp);
+ dcp->dpa_count++;
+ return (0);
+}
+
+/*
+ * We've been asked to load data that belongs to another process. As such we're
+ * going to pgrab it at this instant, load everything that we might ever care
+ * about, and then drive on. The reason for this is that the process that we're
+ * interested in might be changing. As long as we have grabbed it, then this
+ * can't be a problem for us.
+ *
+ * For now, we're actually going to punt on most things and just try to get CTF
+ * data, nothing else. Basically this is only useful as a source of type
+ * information, we can't go and do the stacktrace lookups, etc.
+ */
+static int
+dt_module_load_proc(dtrace_hdl_t *dtp, dt_module_t *dmp)
+{
+ struct ps_prochandle *p;
+ dt_module_cb_arg_t arg;
+
+ /*
+ * Note that on success we do not release this hold. We must hold this
+ * for our life time.
+ */
+ p = dt_proc_grab(dtp, dmp->dm_pid, 0, PGRAB_RDONLY | PGRAB_FORCE);
+ if (p == NULL) {
+ dt_dprintf("failed to grab pid: %d\n", (int)dmp->dm_pid);
+ return (dt_set_errno(dtp, EDT_CANTLOAD));
+ }
+ dt_proc_lock(dtp, p);
+
+ arg.dpa_proc = p;
+ arg.dpa_dtp = dtp;
+ arg.dpa_dmp = dmp;
+ arg.dpa_count = 0;
+ if (Pobject_iter_resolved(p, dt_module_load_proc_count, &arg) != 0) {
+ dt_dprintf("failed to iterate objects\n");
+ dt_proc_release(dtp, p);
+ return (dt_set_errno(dtp, EDT_CANTLOAD));
+ }
+
+ if (arg.dpa_count == 0) {
+ dt_dprintf("no ctf data present\n");
+ dt_proc_unlock(dtp, p);
+ dt_proc_release(dtp, p);
+ return (dt_set_errno(dtp, EDT_CANTLOAD));
+ }
+
+ dmp->dm_libctfp = malloc(sizeof (ctf_file_t *) * arg.dpa_count);
+ if (dmp->dm_libctfp == NULL) {
+ dt_proc_unlock(dtp, p);
+ dt_proc_release(dtp, p);
+ return (dt_set_errno(dtp, EDT_NOMEM));
+ }
+ bzero(dmp->dm_libctfp, sizeof (ctf_file_t *) * arg.dpa_count);
+
+ dmp->dm_libctfn = malloc(sizeof (char *) * arg.dpa_count);
+ if (dmp->dm_libctfn == NULL) {
+ free(dmp->dm_libctfp);
+ dt_proc_unlock(dtp, p);
+ dt_proc_release(dtp, p);
+ return (dt_set_errno(dtp, EDT_NOMEM));
+ }
+ bzero(dmp->dm_libctfn, sizeof (char *) * arg.dpa_count);
+
+ dmp->dm_nctflibs = arg.dpa_count;
+
+ arg.dpa_count = 0;
+ if (Pobject_iter_resolved(p, dt_module_load_proc_build, &arg) != 0) {
+ dt_proc_unlock(dtp, p);
+ dt_module_unload(dtp, dmp);
+ dt_proc_release(dtp, p);
+ return (dt_set_errno(dtp, EDT_CANTLOAD));
+ }
+ assert(arg.dpa_count == dmp->dm_nctflibs);
+ dt_dprintf("loaded %d ctf modules for pid %d\n", arg.dpa_count,
+ (int)dmp->dm_pid);
+
+ dt_proc_unlock(dtp, p);
+ dt_proc_release(dtp, p);
+ dmp->dm_flags |= DT_DM_LOADED;
+
+ return (0);
+}
+
int
dt_module_load(dtrace_hdl_t *dtp, dt_module_t *dmp)
{
if (dmp->dm_flags & DT_DM_LOADED)
return (0); /* module is already loaded */
+ if (dmp->dm_pid != 0)
+ return (dt_module_load_proc(dtp, dmp));
+
dmp->dm_ctdata.cts_name = ".SUNW_ctf";
dmp->dm_ctdata.cts_type = SHT_PROGBITS;
dmp->dm_ctdata.cts_flags = 0;
dmp->dm_ctdata.cts_data = NULL;
dmp->dm_ctdata.cts_size = 0;
@@ -593,10 +782,18 @@
dmp->dm_flags |= DT_DM_LOADED;
return (0);
}
+int
+dt_module_hasctf(dtrace_hdl_t *dtp, dt_module_t *dmp)
+{
+ if (dmp->dm_pid != 0 && dmp->dm_nctflibs > 0)
+ return (1);
+ return (dt_module_getctf(dtp, dmp) != NULL);
+}
+
ctf_file_t *
dt_module_getctf(dtrace_hdl_t *dtp, dt_module_t *dmp)
{
const char *parent;
dt_module_t *pmp;
@@ -666,13 +863,26 @@
/*ARGSUSED*/
void
dt_module_unload(dtrace_hdl_t *dtp, dt_module_t *dmp)
{
+ int i;
+
ctf_close(dmp->dm_ctfp);
dmp->dm_ctfp = NULL;
+ if (dmp->dm_libctfp != NULL) {
+ for (i = 0; i < dmp->dm_nctflibs; i++) {
+ ctf_close(dmp->dm_libctfp[i]);
+ free(dmp->dm_libctfn[i]);
+ }
+ free(dmp->dm_libctfp);
+ free(dmp->dm_libctfn);
+ dmp->dm_libctfp = NULL;
+ dmp->dm_nctflibs = 0;
+ }
+
bzero(&dmp->dm_ctdata, sizeof (ctf_sect_t));
bzero(&dmp->dm_symtab, sizeof (ctf_sect_t));
bzero(&dmp->dm_strtab, sizeof (ctf_sect_t));
if (dmp->dm_symbuckets != NULL) {
@@ -709,10 +919,12 @@
}
(void) elf_end(dmp->dm_elf);
dmp->dm_elf = NULL;
+ dmp->dm_pid = 0;
+
dmp->dm_flags &= ~DT_DM_LOADED;
}
void
dt_module_destroy(dtrace_hdl_t *dtp, dt_module_t *dmp)
@@ -797,10 +1009,38 @@
return ("64-bit");
else
return ("32-bit");
}
+/* ARGSUSED */
+int
+dt_module_getlibid(dtrace_hdl_t *dtp, dt_module_t *dmp, const ctf_file_t *fp)
+{
+ int i;
+
+ for (i = 0; i < dmp->dm_nctflibs; i++) {
+ if (dmp->dm_libctfp[i] == fp)
+ return (i);
+ }
+
+ return (-1);
+}
+
+/* ARGSUSED */
+ctf_file_t *
+dt_module_getctflib(dtrace_hdl_t *dtp, dt_module_t *dmp, const char *name)
+{
+ int i;
+
+ for (i = 0; i < dmp->dm_nctflibs; i++) {
+ if (strcmp(dmp->dm_libctfn[i], name) == 0)
+ return (dmp->dm_libctfp[i]);
+ }
+
+ return (NULL);
+}
+
/*
* Update our module cache by adding an entry for the specified module 'name'.
* We create the dt_module_t and populate it using /system/object/<name>/.
*/
static void
@@ -1138,12 +1378,14 @@
{
dtrace_typeinfo_t ti;
dt_module_t *dmp;
int found = 0;
ctf_id_t id;
- uint_t n;
+ uint_t n, i;
int justone;
+ ctf_file_t *fp;
+ char *buf, *p, *q;
uint_t mask = 0; /* mask of dt_module flags to match */
uint_t bits = 0; /* flag bits that must be present */
if (object != DTRACE_OBJ_EVERY &&
@@ -1154,11 +1396,10 @@
if (dt_module_load(dtp, dmp) == -1)
return (-1); /* dt_errno is set for us */
n = 1;
justone = 1;
-
} else {
if (object == DTRACE_OBJ_KMODS)
mask = bits = DT_DM_KERNEL;
else if (object == DTRACE_OBJ_UMODS)
mask = DT_DM_KERNEL;
@@ -1178,11 +1419,11 @@
/*
* If we can't load the CTF container, continue on to the next
* module. If our search was scoped to only one module then
* return immediately leaving dt_errno unmodified.
*/
- if (dt_module_getctf(dtp, dmp) == NULL) {
+ if (dt_module_hasctf(dtp, dmp) == 0) {
if (justone)
return (-1);
continue;
}
@@ -1190,17 +1431,42 @@
* Look up the type in the module's CTF container. If our
* match is a forward declaration tag, save this choice in
* 'tip' and keep going in the hope that we will locate the
* underlying structure definition. Otherwise just return.
*/
- if ((id = ctf_lookup_by_name(dmp->dm_ctfp, name)) != CTF_ERR) {
+ if (dmp->dm_pid == 0) {
+ id = ctf_lookup_by_name(dmp->dm_ctfp, name);
+ fp = dmp->dm_ctfp;
+ } else {
+ if ((p = strchr(name, '`')) != NULL) {
+ buf = strdup(name);
+ if (buf == NULL)
+ return (dt_set_errno(dtp, EDT_NOMEM));
+ p = strchr(buf, '`');
+ if ((q = strchr(p + 1, '`')) != NULL)
+ p = q;
+ *p = '\0';
+ fp = dt_module_getctflib(dtp, dmp, buf);
+ if (fp == NULL || (id = ctf_lookup_by_name(fp,
+ p + 1)) == CTF_ERR)
+ id = CTF_ERR;
+ free(buf);
+ } else {
+ for (i = 0; i < dmp->dm_nctflibs; i++) {
+ fp = dmp->dm_libctfp[i];
+ id = ctf_lookup_by_name(fp, name);
+ if (id != CTF_ERR)
+ break;
+ }
+ }
+ }
+ if (id != CTF_ERR) {
tip->dtt_object = dmp->dm_name;
- tip->dtt_ctfp = dmp->dm_ctfp;
+ tip->dtt_ctfp = fp;
tip->dtt_type = id;
-
- if (ctf_type_kind(dmp->dm_ctfp, ctf_type_resolve(
- dmp->dm_ctfp, id)) != CTF_K_FORWARD)
+ if (ctf_type_kind(fp, ctf_type_resolve(fp, id)) !=
+ CTF_K_FORWARD)
return (0);
found++;
}
}
@@ -1218,10 +1484,11 @@
dt_module_t *dmp;
tip->dtt_object = NULL;
tip->dtt_ctfp = NULL;
tip->dtt_type = CTF_ERR;
+ tip->dtt_flags = 0;
if ((dmp = dt_module_lookup_by_name(dtp, sip->dts_object)) == NULL)
return (dt_set_errno(dtp, EDT_NOMOD));
if (symp->st_shndx == SHN_UNDEF && dmp->dm_extern != NULL) {