perf probe: Introduce kprobe_trace_event and perf_probe_event
Introduce kprobe_trace_event and perf_probe_event and replace
old probe_point structure with it. probe_point structure is
not enough flexible nor extensible. New data structures
will help implementing further features.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100316220612.32050.33806.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 3942e14..251b4c4 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -319,19 +319,20 @@
*/
/* Show a location */
-static void show_location(Dwarf_Op *op, struct probe_finder *pf)
+static void convert_location(Dwarf_Op *op, struct probe_finder *pf)
{
unsigned int regn;
Dwarf_Word offs = 0;
- int deref = 0, ret;
+ bool ref = false;
const char *regs;
+ struct kprobe_trace_arg *tvar = pf->tvar;
/* TODO: support CFA */
/* If this is based on frame buffer, set the offset */
if (op->atom == DW_OP_fbreg) {
if (pf->fb_ops == NULL)
die("The attribute of frame base is not supported.\n");
- deref = 1;
+ ref = true;
offs = op->number;
op = &pf->fb_ops[0];
}
@@ -339,13 +340,13 @@
if (op->atom >= DW_OP_breg0 && op->atom <= DW_OP_breg31) {
regn = op->atom - DW_OP_breg0;
offs += op->number;
- deref = 1;
+ ref = true;
} else if (op->atom >= DW_OP_reg0 && op->atom <= DW_OP_reg31) {
regn = op->atom - DW_OP_reg0;
} else if (op->atom == DW_OP_bregx) {
regn = op->number;
offs += op->number2;
- deref = 1;
+ ref = true;
} else if (op->atom == DW_OP_regx) {
regn = op->number;
} else
@@ -355,17 +356,15 @@
if (!regs)
die("%u exceeds max register number.", regn);
- if (deref)
- ret = snprintf(pf->buf, pf->len, " %s=%+jd(%s)",
- pf->var, (intmax_t)offs, regs);
- else
- ret = snprintf(pf->buf, pf->len, " %s=%s", pf->var, regs);
- DIE_IF(ret < 0);
- DIE_IF(ret >= pf->len);
+ tvar->value = xstrdup(regs);
+ if (ref) {
+ tvar->ref = xzalloc(sizeof(struct kprobe_trace_arg_ref));
+ tvar->ref->offset = (long)offs;
+ }
}
/* Show a variables in kprobe event format */
-static void show_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
+static void convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
{
Dwarf_Attribute attr;
Dwarf_Op *expr;
@@ -379,50 +378,51 @@
if (ret <= 0 || nexpr == 0)
goto error;
- show_location(expr, pf);
+ convert_location(expr, pf);
/* *expr will be cached in libdw. Don't free it. */
return ;
error:
/* TODO: Support const_value */
die("Failed to find the location of %s at this address.\n"
- " Perhaps, it has been optimized out.", pf->var);
+ " Perhaps, it has been optimized out.", pf->pvar->name);
}
/* Find a variable in a subprogram die */
static void find_variable(Dwarf_Die *sp_die, struct probe_finder *pf)
{
- int ret;
Dwarf_Die vr_die;
/* TODO: Support struct members and arrays */
- if (!is_c_varname(pf->var)) {
- /* Output raw parameters */
- ret = snprintf(pf->buf, pf->len, " %s", pf->var);
- DIE_IF(ret < 0);
- DIE_IF(ret >= pf->len);
- return ;
+ if (!is_c_varname(pf->pvar->name)) {
+ /* Copy raw parameters */
+ pf->tvar->value = xstrdup(pf->pvar->name);
+ } else {
+ pf->tvar->name = xstrdup(pf->pvar->name);
+ pr_debug("Searching '%s' variable in context.\n",
+ pf->pvar->name);
+ /* Search child die for local variables and parameters. */
+ if (!die_find_variable(sp_die, pf->pvar->name, &vr_die))
+ die("Failed to find '%s' in this function.",
+ pf->pvar->name);
+ convert_variable(&vr_die, pf);
}
-
- pr_debug("Searching '%s' variable in context.\n", pf->var);
- /* Search child die for local variables and parameters. */
- if (!die_find_variable(sp_die, pf->var, &vr_die))
- die("Failed to find '%s' in this function.", pf->var);
-
- show_variable(&vr_die, pf);
}
/* Show a probe point to output buffer */
-static void show_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)
+static void convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)
{
- struct probe_point *pp = pf->pp;
+ struct kprobe_trace_event *tev;
Dwarf_Addr eaddr;
Dwarf_Die die_mem;
const char *name;
- char tmp[MAX_PROBE_BUFFER];
- int ret, i, len;
+ int ret, i;
Dwarf_Attribute fb_attr;
size_t nops;
+ if (pf->ntevs == MAX_PROBES)
+ die("Too many( > %d) probe point found.\n", MAX_PROBES);
+ tev = &pf->tevs[pf->ntevs++];
+
/* If no real subprogram, find a real one */
if (!sp_die || dwarf_tag(sp_die) != DW_TAG_subprogram) {
sp_die = die_find_real_subprogram(&pf->cu_die,
@@ -431,31 +431,18 @@
die("Probe point is not found in subprograms.");
}
- /* Output name of probe point */
+ /* Copy the name of probe point */
name = dwarf_diename(sp_die);
if (name) {
dwarf_entrypc(sp_die, &eaddr);
- ret = snprintf(tmp, MAX_PROBE_BUFFER, "%s+%lu", name,
- (unsigned long)(pf->addr - eaddr));
- /* Copy the function name if possible */
- if (!pp->function) {
- pp->function = xstrdup(name);
- pp->offset = (size_t)(pf->addr - eaddr);
- }
- } else {
+ tev->point.symbol = xstrdup(name);
+ tev->point.offset = (unsigned long)(pf->addr - eaddr);
+ } else
/* This function has no name. */
- ret = snprintf(tmp, MAX_PROBE_BUFFER, "0x%jx",
- (uintmax_t)pf->addr);
- if (!pp->function) {
- /* TODO: Use _stext */
- pp->function = xstrdup("");
- pp->offset = (size_t)pf->addr;
- }
- }
- DIE_IF(ret < 0);
- DIE_IF(ret >= MAX_PROBE_BUFFER);
- len = ret;
- pr_debug("Probe point found: %s\n", tmp);
+ tev->point.offset = (unsigned long)pf->addr;
+
+ pr_debug("Probe point found: %s+%lu\n", tev->point.symbol,
+ tev->point.offset);
/* Get the frame base attribute/ops */
dwarf_attr(sp_die, DW_AT_frame_base, &fb_attr);
@@ -465,22 +452,16 @@
/* Find each argument */
/* TODO: use dwarf_cfi_addrframe */
- for (i = 0; i < pp->nr_args; i++) {
- pf->var = pp->args[i];
- pf->buf = &tmp[len];
- pf->len = MAX_PROBE_BUFFER - len;
+ tev->nargs = pf->pev->nargs;
+ tev->args = xzalloc(sizeof(struct kprobe_trace_arg) * tev->nargs);
+ for (i = 0; i < pf->pev->nargs; i++) {
+ pf->pvar = &pf->pev->args[i];
+ pf->tvar = &tev->args[i];
find_variable(sp_die, pf);
- len += strlen(pf->buf);
}
/* *pf->fb_ops will be cached in libdw. Don't free it. */
pf->fb_ops = NULL;
-
- if (pp->found == MAX_PROBES)
- die("Too many( > %d) probe point found.\n", MAX_PROBES);
-
- pp->probes[pp->found] = xstrdup(tmp);
- pp->found++;
}
/* Find probe point from its line number */
@@ -512,7 +493,7 @@
(int)i, lineno, (uintmax_t)addr);
pf->addr = addr;
- show_probe_point(NULL, pf);
+ convert_probe_point(NULL, pf);
/* Continuing, because target line might be inlined. */
}
}
@@ -563,7 +544,7 @@
if (list_empty(&pf->lcache)) {
/* Matching lazy line pattern */
ret = find_lazy_match_lines(&pf->lcache, pf->fname,
- pf->pp->lazy_line);
+ pf->pev->point.lazy_line);
if (ret <= 0)
die("No matched lines found in %s.", pf->fname);
}
@@ -596,7 +577,7 @@
(int)i, lineno, (unsigned long long)addr);
pf->addr = addr;
- show_probe_point(sp_die, pf);
+ convert_probe_point(sp_die, pf);
/* Continuing, because target line might be inlined. */
}
/* TODO: deallocate lines, but how? */
@@ -605,7 +586,7 @@
static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
{
struct probe_finder *pf = (struct probe_finder *)data;
- struct probe_point *pp = pf->pp;
+ struct perf_probe_point *pp = &pf->pev->point;
if (pp->lazy_line)
find_probe_point_lazy(in_die, pf);
@@ -616,7 +597,7 @@
pr_debug("found inline addr: 0x%jx\n",
(uintmax_t)pf->addr);
- show_probe_point(in_die, pf);
+ convert_probe_point(in_die, pf);
}
return DWARF_CB_OK;
@@ -626,7 +607,7 @@
static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
{
struct probe_finder *pf = (struct probe_finder *)data;
- struct probe_point *pp = pf->pp;
+ struct perf_probe_point *pp = &pf->pev->point;
/* Check tag and diename */
if (dwarf_tag(sp_die) != DW_TAG_subprogram ||
@@ -646,7 +627,7 @@
pf->addr = die_get_entrypc(sp_die);
pf->addr += pp->offset;
/* TODO: Check the address in this function */
- show_probe_point(sp_die, pf);
+ convert_probe_point(sp_die, pf);
}
} else
/* Inlined function: search instances */
@@ -660,20 +641,25 @@
dwarf_getfuncs(&pf->cu_die, probe_point_search_cb, pf, 0);
}
-/* Find a probe point */
-int find_probe_point(int fd, struct probe_point *pp)
+/* Find kprobe_trace_events specified by perf_probe_event from debuginfo */
+int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,
+ struct kprobe_trace_event **tevs)
{
- struct probe_finder pf = {.pp = pp};
+ struct probe_finder pf = {.pev = pev};
+ struct perf_probe_point *pp = &pev->point;
Dwarf_Off off, noff;
size_t cuhl;
Dwarf_Die *diep;
Dwarf *dbg;
+ pf.tevs = xzalloc(sizeof(struct kprobe_trace_event) * MAX_PROBES);
+ *tevs = pf.tevs;
+ pf.ntevs = 0;
+
dbg = dwarf_begin(fd, DWARF_C_READ);
if (!dbg)
return -ENOENT;
- pp->found = 0;
off = 0;
line_list__init(&pf.lcache);
/* Loop on CUs (Compilation Unit) */
@@ -704,7 +690,7 @@
line_list__free(&pf.lcache);
dwarf_end(dbg);
- return pp->found;
+ return pf.ntevs;
}
/* Find line range from its line number */