PERFORCE change 135757 for review
John Birrell
jb at FreeBSD.org
Tue Feb 19 23:19:57 UTC 2008
http://perforce.freebsd.org/chv.cgi?CH=135757
Change 135757 by jb at jb_freebsd1 on 2008/02/19 23:19:51
Add code to implement probe argument descriptions by interpreting
the CTF data.
Affected files ...
.. //depot/projects/dtrace/src/sys/cddl/dev/fbt/fbt.c#8 edit
Differences ...
==== //depot/projects/dtrace/src/sys/cddl/dev/fbt/fbt.c#8 (text+ko) ====
@@ -60,7 +60,6 @@
#include <sys/dtrace.h>
-MALLOC_DECLARE(M_FBT);
MALLOC_DEFINE(M_FBT, "fbt", "Function Boundary Tracing");
#define FBT_PUSHL_EBP 0x55
@@ -83,6 +82,7 @@
static d_open_t fbt_open;
static int fbt_unload(void);
+static void fbt_getargdesc(void *, dtrace_id_t, void *, dtrace_argdesc_t *);
static void fbt_provide_module(void *, modctl_t *);
static void fbt_destroy(void *, dtrace_id_t, void *);
static void fbt_enable(void *, dtrace_id_t, void *);
@@ -117,7 +117,7 @@
fbt_disable,
fbt_suspend,
fbt_resume,
- NULL,
+ fbt_getargdesc,
NULL,
NULL,
fbt_destroy
@@ -136,6 +136,7 @@
int fbtp_loadcnt;
int fbtp_primary;
int fbtp_invop_cnt;
+ int fbtp_symindx;
struct fbt_probe *fbtp_next;
} fbt_probe_t;
@@ -206,7 +207,8 @@
}
static int
-fbt_provide_module_function(linker_file_t lf, linker_symval_t *symval, void *opaque)
+fbt_provide_module_function(linker_file_t lf, int symindx,
+ linker_symval_t *symval, void *opaque)
{
char *modname = opaque;
const char *name = symval->name;
@@ -271,6 +273,7 @@
fbt->fbtp_rval = DTRACE_INVOP_PUSHL_EBP;
fbt->fbtp_savedval = *instr;
fbt->fbtp_patchval = FBT_PATCHVAL;
+ fbt->fbtp_symindx = symindx;
fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)];
fbt_probetab[FBT_ADDR2NDX(instr)] = fbt;
@@ -357,6 +360,7 @@
fbt->fbtp_patchpoint = instr;
fbt->fbtp_ctl = lf;
fbt->fbtp_loadcnt = lf->loadcnt;
+ fbt->fbtp_symindx = symindx;
#ifndef __amd64__
if (*instr == FBT_POPL_EBP) {
@@ -386,7 +390,6 @@
goto again;
}
-/*ARGSUSED*/
static void
fbt_provide_module(void *arg, modctl_t *lf)
{
@@ -437,7 +440,6 @@
(void) linker_file_function_listall(lf, fbt_provide_module_function, modname);
}
-/* ARGSUSED */
static void
fbt_destroy(void *arg, dtrace_id_t id, void *parg)
{
@@ -476,7 +478,6 @@
} while (fbt != NULL);
}
-/* ARGSUSED */
static void
fbt_enable(void *arg, dtrace_id_t id, void *parg)
{
@@ -505,7 +506,6 @@
}
}
-/* ARGSUSED */
static void
fbt_disable(void *arg, dtrace_id_t id, void *parg)
{
@@ -522,7 +522,6 @@
*fbt->fbtp_patchpoint = fbt->fbtp_savedval;
}
-/*ARGSUSED*/
static void
fbt_suspend(void *arg, dtrace_id_t id, void *parg)
{
@@ -538,7 +537,6 @@
*fbt->fbtp_patchpoint = fbt->fbtp_savedval;
}
-/*ARGSUSED*/
static void
fbt_resume(void *arg, dtrace_id_t id, void *parg)
{
@@ -554,7 +552,758 @@
*fbt->fbtp_patchpoint = fbt->fbtp_patchval;
}
+static int
+fbt_ctfoff_init(modctl_t *lf, linker_ctf_t *lc)
+{
+ const Elf_Sym *symp = lc->symtab;;
+ const char *name;
+ const ctf_header_t *hp = (const ctf_header_t *) lc->ctftab;
+ const uint8_t *ctfdata = lc->ctftab + sizeof(ctf_header_t);
+ int i;
+ uint32_t *ctfoff;
+ uint32_t objtoff = hp->cth_objtoff;
+ uint32_t funcoff = hp->cth_funcoff;
+ ushort_t info;
+ ushort_t vlen;
+
+ /* Sanity check. */
+ if (hp->cth_magic != CTF_MAGIC) {
+ printf("Bad magic value in CTF data of '%s'\n",lf->pathname);
+ return (EINVAL);
+ }
+
+ if (lc->symtab == NULL) {
+ printf("No symbol table in '%s'\n",lf->pathname);
+ return (EINVAL);
+ }
+
+ if ((ctfoff = malloc(sizeof(uint32_t) * lc->nsym, M_LINKER, M_WAITOK)) == NULL)
+ return (ENOMEM);
+
+ *lc->ctfoffp = ctfoff;
+
+ for (i = 0; i < lc->nsym; i++, ctfoff++, symp++) {
+ if (symp->st_name == 0 || symp->st_shndx == SHN_UNDEF) {
+ *ctfoff = 0xffffffff;
+ continue;
+ }
+
+ if (symp->st_name < lc->strcnt)
+ name = lc->strtab + symp->st_name;
+ else
+ name = "(?)";
+
+ switch (ELF_ST_TYPE(symp->st_info)) {
+ case STT_OBJECT:
+ if (objtoff >= hp->cth_funcoff ||
+ (symp->st_shndx == SHN_ABS && symp->st_value == 0)) {
+ *ctfoff = 0xffffffff;
+ break;
+ }
+
+ *ctfoff = objtoff;
+ objtoff += sizeof (ushort_t);
+ break;
+
+ case STT_FUNC:
+ if (funcoff >= hp->cth_typeoff) {
+ *ctfoff = 0xffffffff;
+ break;
+ }
+
+ *ctfoff = funcoff;
+
+ info = *((const ushort_t *)(ctfdata + funcoff));
+ vlen = CTF_INFO_VLEN(info);
+
+ /*
+ * If we encounter a zero pad at the end, just skip it.
+ * Otherwise skip over the function and its return type
+ * (+2) and the argument list (vlen).
+ */
+ if (CTF_INFO_KIND(info) == CTF_K_UNKNOWN && vlen == 0)
+ funcoff += sizeof (ushort_t); /* skip pad */
+ else
+ funcoff += sizeof (ushort_t) * (vlen + 2);
+ break;
+
+ default:
+ *ctfoff = 0xffffffff;
+ break;
+ }
+ }
+
+ return (0);
+}
+
+static ssize_t
+fbt_get_ctt_size(uint8_t version, const ctf_type_t *tp, ssize_t *sizep,
+ ssize_t *incrementp)
+{
+ ssize_t size, increment;
+
+ if (version > CTF_VERSION_1 &&
+ tp->ctt_size == CTF_LSIZE_SENT) {
+ size = CTF_TYPE_LSIZE(tp);
+ increment = sizeof (ctf_type_t);
+ } else {
+ size = tp->ctt_size;
+ increment = sizeof (ctf_stype_t);
+ }
+
+ if (sizep)
+ *sizep = size;
+ if (incrementp)
+ *incrementp = increment;
+
+ return (size);
+}
+
+static int
+fbt_typoff_init(linker_ctf_t *lc)
+{
+ const ctf_header_t *hp = (const ctf_header_t *) lc->ctftab;
+ const ctf_type_t *tbuf;
+ const ctf_type_t *tend;
+ const ctf_type_t *tp;
+ const uint8_t *ctfdata = lc->ctftab + sizeof(ctf_header_t);
+ int ctf_typemax = 0;
+ uint32_t *xp;
+ ulong_t pop[CTF_K_MAX + 1] = { 0 };
+
+
+ /* Sanity check. */
+ if (hp->cth_magic != CTF_MAGIC)
+ return (EINVAL);
+
+ tbuf = (const ctf_type_t *) (ctfdata + hp->cth_typeoff);
+ tend = (const ctf_type_t *) (ctfdata + hp->cth_stroff);
+
+ int child = hp->cth_parname != 0;
+
+ /*
+ * We make two passes through the entire type section. In this first
+ * pass, we count the number of each type and the total number of types.
+ */
+ for (tp = tbuf; tp < tend; ctf_typemax++) {
+ ushort_t kind = CTF_INFO_KIND(tp->ctt_info);
+ ulong_t vlen = CTF_INFO_VLEN(tp->ctt_info);
+ ssize_t size, increment;
+
+ size_t vbytes;
+ uint_t n;
+
+ (void) fbt_get_ctt_size(hp->cth_version, tp, &size, &increment);
+
+ switch (kind) {
+ case CTF_K_INTEGER:
+ case CTF_K_FLOAT:
+ vbytes = sizeof (uint_t);
+ break;
+ case CTF_K_ARRAY:
+ vbytes = sizeof (ctf_array_t);
+ break;
+ case CTF_K_FUNCTION:
+ vbytes = sizeof (ushort_t) * (vlen + (vlen & 1));
+ break;
+ case CTF_K_STRUCT:
+ case CTF_K_UNION:
+ if (size < CTF_LSTRUCT_THRESH) {
+ ctf_member_t *mp = (ctf_member_t *)
+ ((uintptr_t)tp + increment);
+
+ vbytes = sizeof (ctf_member_t) * vlen;
+ for (n = vlen; n != 0; n--, mp++)
+ child |= CTF_TYPE_ISCHILD(mp->ctm_type);
+ } else {
+ ctf_lmember_t *lmp = (ctf_lmember_t *)
+ ((uintptr_t)tp + increment);
+
+ vbytes = sizeof (ctf_lmember_t) * vlen;
+ for (n = vlen; n != 0; n--, lmp++)
+ child |=
+ CTF_TYPE_ISCHILD(lmp->ctlm_type);
+ }
+ break;
+ case CTF_K_ENUM:
+ vbytes = sizeof (ctf_enum_t) * vlen;
+ break;
+ case CTF_K_FORWARD:
+ /*
+ * For forward declarations, ctt_type is the CTF_K_*
+ * kind for the tag, so bump that population count too.
+ * If ctt_type is unknown, treat the tag as a struct.
+ */
+ if (tp->ctt_type == CTF_K_UNKNOWN ||
+ tp->ctt_type >= CTF_K_MAX)
+ pop[CTF_K_STRUCT]++;
+ else
+ pop[tp->ctt_type]++;
+ /*FALLTHRU*/
+ case CTF_K_UNKNOWN:
+ vbytes = 0;
+ break;
+ case CTF_K_POINTER:
+ case CTF_K_TYPEDEF:
+ case CTF_K_VOLATILE:
+ case CTF_K_CONST:
+ case CTF_K_RESTRICT:
+ child |= CTF_TYPE_ISCHILD(tp->ctt_type);
+ vbytes = 0;
+ break;
+ default:
+ printf("%s(%d): detected invalid CTF kind -- %u\n", __func__, __LINE__, kind);
+ return (EIO);
+ }
+ tp = (ctf_type_t *)((uintptr_t)tp + increment + vbytes);
+ pop[kind]++;
+ }
+
+ *lc->typlenp = ctf_typemax;
+
+ if ((xp = malloc(sizeof(uint32_t) * ctf_typemax, M_LINKER, M_ZERO | M_WAITOK)) == NULL)
+ return (ENOMEM);
+
+ *lc->typoffp = xp;
+
+ /* type id 0 is used as a sentinel value */
+ *xp++ = 0;
+
+ /*
+ * In the second pass, fill in the type offset.
+ */
+ for (tp = tbuf; tp < tend; xp++) {
+ ushort_t kind = CTF_INFO_KIND(tp->ctt_info);
+ ulong_t vlen = CTF_INFO_VLEN(tp->ctt_info);
+ ssize_t size, increment;
+
+ size_t vbytes;
+ uint_t n;
+
+ (void) fbt_get_ctt_size(hp->cth_version, tp, &size, &increment);
+
+ switch (kind) {
+ case CTF_K_INTEGER:
+ case CTF_K_FLOAT:
+ vbytes = sizeof (uint_t);
+ break;
+ case CTF_K_ARRAY:
+ vbytes = sizeof (ctf_array_t);
+ break;
+ case CTF_K_FUNCTION:
+ vbytes = sizeof (ushort_t) * (vlen + (vlen & 1));
+ break;
+ case CTF_K_STRUCT:
+ case CTF_K_UNION:
+ if (size < CTF_LSTRUCT_THRESH) {
+ ctf_member_t *mp = (ctf_member_t *)
+ ((uintptr_t)tp + increment);
+
+ vbytes = sizeof (ctf_member_t) * vlen;
+ for (n = vlen; n != 0; n--, mp++)
+ child |= CTF_TYPE_ISCHILD(mp->ctm_type);
+ } else {
+ ctf_lmember_t *lmp = (ctf_lmember_t *)
+ ((uintptr_t)tp + increment);
+
+ vbytes = sizeof (ctf_lmember_t) * vlen;
+ for (n = vlen; n != 0; n--, lmp++)
+ child |=
+ CTF_TYPE_ISCHILD(lmp->ctlm_type);
+ }
+ break;
+ case CTF_K_ENUM:
+ vbytes = sizeof (ctf_enum_t) * vlen;
+ break;
+ case CTF_K_FORWARD:
+ case CTF_K_UNKNOWN:
+ vbytes = 0;
+ break;
+ case CTF_K_POINTER:
+ case CTF_K_TYPEDEF:
+ case CTF_K_VOLATILE:
+ case CTF_K_CONST:
+ case CTF_K_RESTRICT:
+ vbytes = 0;
+ break;
+ default:
+ printf("%s(%d): detected invalid CTF kind -- %u\n", __func__, __LINE__, kind);
+ return (EIO);
+ }
+ *xp = (uint32_t)((uintptr_t) tp - (uintptr_t) ctfdata);
+ tp = (ctf_type_t *)((uintptr_t)tp + increment + vbytes);
+ }
+
+ return (0);
+}
+
+/*
+ * CTF Declaration Stack
+ *
+ * In order to implement ctf_type_name(), we must convert a type graph back
+ * into a C type declaration. Unfortunately, a type graph represents a storage
+ * class ordering of the type whereas a type declaration must obey the C rules
+ * for operator precedence, and the two orderings are frequently in conflict.
+ * For example, consider these CTF type graphs and their C declarations:
+ *
+ * CTF_K_POINTER -> CTF_K_FUNCTION -> CTF_K_INTEGER : int (*)()
+ * CTF_K_POINTER -> CTF_K_ARRAY -> CTF_K_INTEGER : int (*)[]
+ *
+ * In each case, parentheses are used to raise operator * to higher lexical
+ * precedence, so the string form of the C declaration cannot be constructed by
+ * walking the type graph links and forming the string from left to right.
+ *
+ * The functions in this file build a set of stacks from the type graph nodes
+ * corresponding to the C operator precedence levels in the appropriate order.
+ * The code in ctf_type_name() can then iterate over the levels and nodes in
+ * lexical precedence order and construct the final C declaration string.
+ */
+typedef struct ctf_list {
+ struct ctf_list *l_prev; /* previous pointer or tail pointer */
+ struct ctf_list *l_next; /* next pointer or head pointer */
+} ctf_list_t;
+
+#define ctf_list_prev(elem) ((void *)(((ctf_list_t *)(elem))->l_prev))
+#define ctf_list_next(elem) ((void *)(((ctf_list_t *)(elem))->l_next))
+
+typedef enum {
+ CTF_PREC_BASE,
+ CTF_PREC_POINTER,
+ CTF_PREC_ARRAY,
+ CTF_PREC_FUNCTION,
+ CTF_PREC_MAX
+} ctf_decl_prec_t;
+
+typedef struct ctf_decl_node {
+ ctf_list_t cd_list; /* linked list pointers */
+ ctf_id_t cd_type; /* type identifier */
+ uint_t cd_kind; /* type kind */
+ uint_t cd_n; /* type dimension if array */
+} ctf_decl_node_t;
+
+typedef struct ctf_decl {
+ ctf_list_t cd_nodes[CTF_PREC_MAX]; /* declaration node stacks */
+ int cd_order[CTF_PREC_MAX]; /* storage order of decls */
+ ctf_decl_prec_t cd_qualp; /* qualifier precision */
+ ctf_decl_prec_t cd_ordp; /* ordered precision */
+ char *cd_buf; /* buffer for output */
+ char *cd_ptr; /* buffer location */
+ char *cd_end; /* buffer limit */
+ size_t cd_len; /* buffer space required */
+ int cd_err; /* saved error value */
+} ctf_decl_t;
+
+/*
+ * Simple doubly-linked list append routine. This implementation assumes that
+ * each list element contains an embedded ctf_list_t as the first member.
+ * An additional ctf_list_t is used to store the head (l_next) and tail
+ * (l_prev) pointers. The current head and tail list elements have their
+ * previous and next pointers set to NULL, respectively.
+ */
+static void
+ctf_list_append(ctf_list_t *lp, void *new)
+{
+ ctf_list_t *p = lp->l_prev; /* p = tail list element */
+ ctf_list_t *q = new; /* q = new list element */
+
+ lp->l_prev = q;
+ q->l_prev = p;
+ q->l_next = NULL;
+
+ if (p != NULL)
+ p->l_next = q;
+ else
+ lp->l_next = q;
+}
+
+/*
+ * Prepend the specified existing element to the given ctf_list_t. The
+ * existing pointer should be pointing at a struct with embedded ctf_list_t.
+ */
static void
+ctf_list_prepend(ctf_list_t *lp, void *new)
+{
+ ctf_list_t *p = new; /* p = new list element */
+ ctf_list_t *q = lp->l_next; /* q = head list element */
+
+ lp->l_next = p;
+ p->l_prev = NULL;
+ p->l_next = q;
+
+ if (q != NULL)
+ q->l_prev = p;
+ else
+ lp->l_prev = p;
+}
+
+static void
+ctf_decl_init(ctf_decl_t *cd, char *buf, size_t len)
+{
+ int i;
+
+ bzero(cd, sizeof (ctf_decl_t));
+
+ for (i = CTF_PREC_BASE; i < CTF_PREC_MAX; i++)
+ cd->cd_order[i] = CTF_PREC_BASE - 1;
+
+ cd->cd_qualp = CTF_PREC_BASE;
+ cd->cd_ordp = CTF_PREC_BASE;
+
+ cd->cd_buf = buf;
+ cd->cd_ptr = buf;
+ cd->cd_end = buf + len;
+}
+
+static void
+ctf_decl_fini(ctf_decl_t *cd)
+{
+ ctf_decl_node_t *cdp, *ndp;
+ int i;
+
+ for (i = CTF_PREC_BASE; i < CTF_PREC_MAX; i++) {
+ for (cdp = ctf_list_next(&cd->cd_nodes[i]);
+ cdp != NULL; cdp = ndp) {
+ ndp = ctf_list_next(cdp);
+ free(cdp, M_FBT);
+ }
+ }
+}
+
+static const ctf_type_t *
+ctf_lookup_by_id(linker_ctf_t *lc, ctf_id_t type)
+{
+ const ctf_type_t *tp;
+ uint32_t offset;
+ uint32_t *typoff = *lc->typoffp;
+
+ if (type >= *lc->typlenp) {
+ printf("%s(%d): type %d exceeds max %ld\n",__func__,__LINE__,(int) type,*lc->typlenp);
+ return(NULL);
+ }
+
+ /* Check if the type isn't cross-referenced. */
+ if ((offset = typoff[type]) == 0) {
+ printf("%s(%d): type %d isn't cross referenced\n",__func__,__LINE__, (int) type);
+ return(NULL);
+ }
+
+ tp = (const ctf_type_t *)(lc->ctftab + offset + sizeof(ctf_header_t));
+
+ return (tp);
+}
+
+static void
+fbt_array_info(linker_ctf_t *lc, ctf_id_t type, ctf_arinfo_t *arp)
+{
+ const ctf_header_t *hp = (const ctf_header_t *) lc->ctftab;
+ const ctf_type_t *tp;
+ const ctf_array_t *ap;
+ ssize_t increment;
+
+ bzero(arp, sizeof(*arp));
+
+ if ((tp = ctf_lookup_by_id(lc, type)) == NULL)
+ return;
+
+ if (CTF_INFO_KIND(tp->ctt_info) != CTF_K_ARRAY)
+ return;
+
+ (void) fbt_get_ctt_size(hp->cth_version, tp, NULL, &increment);
+
+ ap = (const ctf_array_t *)((uintptr_t)tp + increment);
+ arp->ctr_contents = ap->cta_contents;
+ arp->ctr_index = ap->cta_index;
+ arp->ctr_nelems = ap->cta_nelems;
+}
+
+static const char *
+ctf_strptr(linker_ctf_t *lc, int name)
+{
+ const ctf_header_t *hp = (const ctf_header_t *) lc->ctftab;;
+ const char *strp = "";
+
+ if (name < 0 || name >= hp->cth_strlen)
+ return(strp);
+
+ strp = (const char *)(lc->ctftab + hp->cth_stroff + name + sizeof(ctf_header_t));
+
+ return (strp);
+}
+
+static void
+ctf_decl_push(ctf_decl_t *cd, linker_ctf_t *lc, ctf_id_t type)
+{
+ ctf_decl_node_t *cdp;
+ ctf_decl_prec_t prec;
+ uint_t kind, n = 1;
+ int is_qual = 0;
+
+ const ctf_type_t *tp;
+ ctf_arinfo_t ar;
+
+ if ((tp = ctf_lookup_by_id(lc, type)) == NULL) {
+ cd->cd_err = ENOENT;
+ return;
+ }
+
+ switch (kind = CTF_INFO_KIND(tp->ctt_info)) {
+ case CTF_K_ARRAY:
+ fbt_array_info(lc, type, &ar);
+ ctf_decl_push(cd, lc, ar.ctr_contents);
+ n = ar.ctr_nelems;
+ prec = CTF_PREC_ARRAY;
+ break;
+
+ case CTF_K_TYPEDEF:
+ if (ctf_strptr(lc, tp->ctt_name)[0] == '\0') {
+ ctf_decl_push(cd, lc, tp->ctt_type);
+ return;
+ }
+ prec = CTF_PREC_BASE;
+ break;
+
+ case CTF_K_FUNCTION:
+ ctf_decl_push(cd, lc, tp->ctt_type);
+ prec = CTF_PREC_FUNCTION;
+ break;
+
+ case CTF_K_POINTER:
+ ctf_decl_push(cd, lc, tp->ctt_type);
+ prec = CTF_PREC_POINTER;
+ break;
+
+ case CTF_K_VOLATILE:
+ case CTF_K_CONST:
+ case CTF_K_RESTRICT:
+ ctf_decl_push(cd, lc, tp->ctt_type);
+ prec = cd->cd_qualp;
+ is_qual++;
+ break;
+
+ default:
+ prec = CTF_PREC_BASE;
+ }
+
+ if ((cdp = malloc(sizeof (ctf_decl_node_t), M_FBT, M_WAITOK)) == NULL) {
+ cd->cd_err = EAGAIN;
+ return;
+ }
+
+ cdp->cd_type = type;
+ cdp->cd_kind = kind;
+ cdp->cd_n = n;
+
+ if (ctf_list_next(&cd->cd_nodes[prec]) == NULL)
+ cd->cd_order[prec] = cd->cd_ordp++;
+
+ /*
+ * Reset cd_qualp to the highest precedence level that we've seen so
+ * far that can be qualified (CTF_PREC_BASE or CTF_PREC_POINTER).
+ */
+ if (prec > cd->cd_qualp && prec < CTF_PREC_ARRAY)
+ cd->cd_qualp = prec;
+
+ /*
+ * C array declarators are ordered inside out so prepend them. Also by
+ * convention qualifiers of base types precede the type specifier (e.g.
+ * const int vs. int const) even though the two forms are equivalent.
+ */
+ if (kind == CTF_K_ARRAY || (is_qual && prec == CTF_PREC_BASE))
+ ctf_list_prepend(&cd->cd_nodes[prec], cdp);
+ else
+ ctf_list_append(&cd->cd_nodes[prec], cdp);
+}
+
+static void
+ctf_decl_sprintf(ctf_decl_t *cd, const char *format, ...)
+{
+ size_t len = (size_t)(cd->cd_end - cd->cd_ptr);
+ va_list ap;
+ size_t n;
+
+ va_start(ap, format);
+ n = vsnprintf(cd->cd_ptr, len, format, ap);
+ va_end(ap);
+
+ cd->cd_ptr += MIN(n, len);
+ cd->cd_len += n;
+}
+
+static ssize_t
+fbt_type_name(linker_ctf_t *lc, ctf_id_t type, char *buf, size_t len)
+{
+ ctf_decl_t cd;
+ ctf_decl_node_t *cdp;
+ ctf_decl_prec_t prec, lp, rp;
+ int ptr, arr;
+ uint_t k;
+
+ if (lc == NULL && type == CTF_ERR)
+ return (-1); /* simplify caller code by permitting CTF_ERR */
+
+ ctf_decl_init(&cd, buf, len);
+ ctf_decl_push(&cd, lc, type);
+
+ if (cd.cd_err != 0) {
+ ctf_decl_fini(&cd);
+ return (-1);
+ }
+
+ /*
+ * If the type graph's order conflicts with lexical precedence order
+ * for pointers or arrays, then we need to surround the declarations at
+ * the corresponding lexical precedence with parentheses. This can
+ * result in either a parenthesized pointer (*) as in int (*)() or
+ * int (*)[], or in a parenthesized pointer and array as in int (*[])().
+ */
+ ptr = cd.cd_order[CTF_PREC_POINTER] > CTF_PREC_POINTER;
+ arr = cd.cd_order[CTF_PREC_ARRAY] > CTF_PREC_ARRAY;
+
+ rp = arr ? CTF_PREC_ARRAY : ptr ? CTF_PREC_POINTER : -1;
+ lp = ptr ? CTF_PREC_POINTER : arr ? CTF_PREC_ARRAY : -1;
+
+ k = CTF_K_POINTER; /* avoid leading whitespace (see below) */
+
+ for (prec = CTF_PREC_BASE; prec < CTF_PREC_MAX; prec++) {
+ for (cdp = ctf_list_next(&cd.cd_nodes[prec]);
+ cdp != NULL; cdp = ctf_list_next(cdp)) {
+
+ const ctf_type_t *tp =
+ ctf_lookup_by_id(lc, cdp->cd_type);
+ const char *name = ctf_strptr(lc, tp->ctt_name);
+
+ if (k != CTF_K_POINTER && k != CTF_K_ARRAY)
+ ctf_decl_sprintf(&cd, " ");
+
+ if (lp == prec) {
+ ctf_decl_sprintf(&cd, "(");
+ lp = -1;
+ }
+
+ switch (cdp->cd_kind) {
+ case CTF_K_INTEGER:
+ case CTF_K_FLOAT:
+ case CTF_K_TYPEDEF:
+ ctf_decl_sprintf(&cd, "%s", name);
+ break;
+ case CTF_K_POINTER:
+ ctf_decl_sprintf(&cd, "*");
+ break;
+ case CTF_K_ARRAY:
+ ctf_decl_sprintf(&cd, "[%u]", cdp->cd_n);
+ break;
+ case CTF_K_FUNCTION:
+ ctf_decl_sprintf(&cd, "()");
+ break;
+ case CTF_K_STRUCT:
+ case CTF_K_FORWARD:
+ ctf_decl_sprintf(&cd, "struct %s", name);
+ break;
+ case CTF_K_UNION:
+ ctf_decl_sprintf(&cd, "union %s", name);
+ break;
+ case CTF_K_ENUM:
+ ctf_decl_sprintf(&cd, "enum %s", name);
+ break;
+ case CTF_K_VOLATILE:
+ ctf_decl_sprintf(&cd, "volatile");
+ break;
+ case CTF_K_CONST:
+ ctf_decl_sprintf(&cd, "const");
+ break;
+ case CTF_K_RESTRICT:
+ ctf_decl_sprintf(&cd, "restrict");
+ break;
+ }
+
+ k = cdp->cd_kind;
+ }
+
+ if (rp == prec)
+ ctf_decl_sprintf(&cd, ")");
+ }
+
+ ctf_decl_fini(&cd);
+ return (cd.cd_len);
+}
+
+static void
+fbt_getargdesc(void *arg __unused, dtrace_id_t id __unused, void *parg, dtrace_argdesc_t *desc)
+{
+ const ushort_t *dp;
+ fbt_probe_t *fbt = parg;
+ linker_ctf_t lc;
+ modctl_t *ctl = fbt->fbtp_ctl;
+ int ndx = desc->dtargd_ndx;
+ int symindx = fbt->fbtp_symindx;
+ uint32_t *ctfoff;
+ uint32_t offset;
+ ushort_t info, kind, n;
+
+ desc->dtargd_ndx = DTRACE_ARGNONE;
+
+ /* Get a pointer to the CTF data and it's length. */
+ if (linker_ctf_get(ctl, &lc) != 0)
+ /* No CTF data? Something wrong? *shrug* */
+ return;
+
+ /* Check if this module hasn't been initialised yet. */
+ if (*lc.ctfoffp == NULL) {
+ /*
+ * Initialise the CTF object and function symindx to
+ * byte offset array.
+ */
+ if (fbt_ctfoff_init(ctl, &lc) != 0)
+ return;
+
+ /* Initialise the CTF type to byte offset array. */
+ if (fbt_typoff_init(&lc) != 0)
+ return;
+ }
+
+ ctfoff = *lc.ctfoffp;
+
+ if (ctfoff == NULL || *lc.typoffp == NULL)
+ return;
+
+ /* Check if the symbol index is out of range. */
+ if (symindx >= lc.nsym)
+ return;
+
+ /* Check if the symbol isn't cross-referenced. */
+ if ((offset = ctfoff[symindx]) == 0xffffffff)
+ return;
+
+ dp = (const ushort_t *)(lc.ctftab + offset + sizeof(ctf_header_t));
+
+ info = *dp++;
+ kind = CTF_INFO_KIND(info);
+ n = CTF_INFO_VLEN(info);
+
+ if (kind == CTF_K_UNKNOWN && n == 0) {
+ printf("%s(%d): Unknown function!\n",__func__,__LINE__);
+ return;
+ }
+
+ if (kind != CTF_K_FUNCTION) {
+ printf("%s(%d): Expected a function!\n",__func__,__LINE__);
+ return;
+ }
+
+ /* Check if the requested argument doesn't exist. */
+ if (ndx >= n)
+ return;
+
+ /* Skip the return type and arguments up to the one requested. */
+ dp += ndx + 1;
+
+ if (fbt_type_name(&lc, *dp, desc->dtargd_native, sizeof(desc->dtargd_native)) > 0)
+ desc->dtargd_ndx = ndx;
+
+ return;
+}
+
+static void
fbt_load(void *dummy)
{
/* Create the /dev/dtrace/fbt entry. */
@@ -602,7 +1351,6 @@
return (error);
}
-/* ARGSUSED */
static int
fbt_modevent(module_t mod __unused, int type, void *data __unused)
{
@@ -627,7 +1375,6 @@
return (error);
}
-/* ARGSUSED */
static int
fbt_open(struct cdev *dev __unused, int oflags __unused, int devtype __unused, struct thread *td __unused)
{
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