summaryrefslogtreecommitdiffstats
path: root/tools/perf/util/probe-file.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--tools/perf/util/probe-file.c1200
1 files changed, 1200 insertions, 0 deletions
diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
new file mode 100644
index 000000000..3d50de321
--- /dev/null
+++ b/tools/perf/util/probe-file.c
@@ -0,0 +1,1200 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * probe-file.c : operate ftrace k/uprobe events files
+ *
+ * Written by Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
+ */
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/uio.h>
+#include <unistd.h>
+#include <linux/zalloc.h>
+#include "namespaces.h"
+#include "event.h"
+#include "strlist.h"
+#include "strfilter.h"
+#include "debug.h"
+#include "build-id.h"
+#include "dso.h"
+#include "color.h"
+#include "symbol.h"
+#include "strbuf.h"
+#include <api/fs/tracing_path.h>
+#include <api/fs/fs.h>
+#include "probe-event.h"
+#include "probe-file.h"
+#include "session.h"
+#include "perf_regs.h"
+#include "string2.h"
+
+/* 4096 - 2 ('\n' + '\0') */
+#define MAX_CMDLEN 4094
+
+static bool print_common_warning(int err, bool readwrite)
+{
+ if (err == -EACCES)
+ pr_warning("No permission to %s tracefs.\nPlease %s\n",
+ readwrite ? "write" : "read",
+ readwrite ? "run this command again with sudo." :
+ "try 'sudo mount -o remount,mode=755 /sys/kernel/tracing/'");
+ else
+ return false;
+
+ return true;
+}
+
+static bool print_configure_probe_event(int kerr, int uerr)
+{
+ const char *config, *file;
+
+ if (kerr == -ENOENT && uerr == -ENOENT) {
+ file = "{k,u}probe_events";
+ config = "CONFIG_KPROBE_EVENTS=y and CONFIG_UPROBE_EVENTS=y";
+ } else if (kerr == -ENOENT) {
+ file = "kprobe_events";
+ config = "CONFIG_KPROBE_EVENTS=y";
+ } else if (uerr == -ENOENT) {
+ file = "uprobe_events";
+ config = "CONFIG_UPROBE_EVENTS=y";
+ } else
+ return false;
+
+ if (!debugfs__configured() && !tracefs__configured())
+ pr_warning("Debugfs or tracefs is not mounted\n"
+ "Please try 'sudo mount -t tracefs nodev /sys/kernel/tracing/'\n");
+ else
+ pr_warning("%s/%s does not exist.\nPlease rebuild kernel with %s.\n",
+ tracing_path_mount(), file, config);
+
+ return true;
+}
+
+static void print_open_warning(int err, bool uprobe, bool readwrite)
+{
+ char sbuf[STRERR_BUFSIZE];
+
+ if (print_common_warning(err, readwrite))
+ return;
+
+ if (print_configure_probe_event(uprobe ? 0 : err, uprobe ? err : 0))
+ return;
+
+ pr_warning("Failed to open %s/%cprobe_events: %s\n",
+ tracing_path_mount(), uprobe ? 'u' : 'k',
+ str_error_r(-err, sbuf, sizeof(sbuf)));
+}
+
+static void print_both_open_warning(int kerr, int uerr, bool readwrite)
+{
+ char sbuf[STRERR_BUFSIZE];
+
+ if (kerr == uerr && print_common_warning(kerr, readwrite))
+ return;
+
+ if (print_configure_probe_event(kerr, uerr))
+ return;
+
+ if (kerr < 0)
+ pr_warning("Failed to open %s/kprobe_events: %s.\n",
+ tracing_path_mount(),
+ str_error_r(-kerr, sbuf, sizeof(sbuf)));
+ if (uerr < 0)
+ pr_warning("Failed to open %s/uprobe_events: %s.\n",
+ tracing_path_mount(),
+ str_error_r(-uerr, sbuf, sizeof(sbuf)));
+}
+
+int open_trace_file(const char *trace_file, bool readwrite)
+{
+ char buf[PATH_MAX];
+ int ret;
+
+ ret = e_snprintf(buf, PATH_MAX, "%s/%s", tracing_path_mount(), trace_file);
+ if (ret >= 0) {
+ pr_debug("Opening %s write=%d\n", buf, readwrite);
+ if (readwrite && !probe_event_dry_run)
+ ret = open(buf, O_RDWR | O_APPEND, 0);
+ else
+ ret = open(buf, O_RDONLY, 0);
+
+ if (ret < 0)
+ ret = -errno;
+ }
+ return ret;
+}
+
+static int open_kprobe_events(bool readwrite)
+{
+ return open_trace_file("kprobe_events", readwrite);
+}
+
+static int open_uprobe_events(bool readwrite)
+{
+ return open_trace_file("uprobe_events", readwrite);
+}
+
+int probe_file__open(int flag)
+{
+ int fd;
+
+ if (flag & PF_FL_UPROBE)
+ fd = open_uprobe_events(flag & PF_FL_RW);
+ else
+ fd = open_kprobe_events(flag & PF_FL_RW);
+ if (fd < 0)
+ print_open_warning(fd, flag & PF_FL_UPROBE, flag & PF_FL_RW);
+
+ return fd;
+}
+
+int probe_file__open_both(int *kfd, int *ufd, int flag)
+{
+ if (!kfd || !ufd)
+ return -EINVAL;
+
+ *kfd = open_kprobe_events(flag & PF_FL_RW);
+ *ufd = open_uprobe_events(flag & PF_FL_RW);
+ if (*kfd < 0 && *ufd < 0) {
+ print_both_open_warning(*kfd, *ufd, flag & PF_FL_RW);
+ return *kfd;
+ }
+
+ return 0;
+}
+
+/* Get raw string list of current kprobe_events or uprobe_events */
+struct strlist *probe_file__get_rawlist(int fd)
+{
+ int ret, idx, fddup;
+ FILE *fp;
+ char buf[MAX_CMDLEN];
+ char *p;
+ struct strlist *sl;
+
+ if (fd < 0)
+ return NULL;
+
+ sl = strlist__new(NULL, NULL);
+ if (sl == NULL)
+ return NULL;
+
+ fddup = dup(fd);
+ if (fddup < 0)
+ goto out_free_sl;
+
+ fp = fdopen(fddup, "r");
+ if (!fp)
+ goto out_close_fddup;
+
+ while (!feof(fp)) {
+ p = fgets(buf, MAX_CMDLEN, fp);
+ if (!p)
+ break;
+
+ idx = strlen(p) - 1;
+ if (p[idx] == '\n')
+ p[idx] = '\0';
+ ret = strlist__add(sl, buf);
+ if (ret < 0) {
+ pr_debug("strlist__add failed (%d)\n", ret);
+ goto out_close_fp;
+ }
+ }
+ fclose(fp);
+
+ return sl;
+
+out_close_fp:
+ fclose(fp);
+ goto out_free_sl;
+out_close_fddup:
+ close(fddup);
+out_free_sl:
+ strlist__delete(sl);
+ return NULL;
+}
+
+static struct strlist *__probe_file__get_namelist(int fd, bool include_group)
+{
+ char buf[128];
+ struct strlist *sl, *rawlist;
+ struct str_node *ent;
+ struct probe_trace_event tev;
+ int ret = 0;
+
+ memset(&tev, 0, sizeof(tev));
+ rawlist = probe_file__get_rawlist(fd);
+ if (!rawlist)
+ return NULL;
+ sl = strlist__new(NULL, NULL);
+ strlist__for_each_entry(ent, rawlist) {
+ ret = parse_probe_trace_command(ent->s, &tev);
+ if (ret < 0)
+ break;
+ if (include_group) {
+ ret = e_snprintf(buf, 128, "%s:%s", tev.group,
+ tev.event);
+ if (ret >= 0)
+ ret = strlist__add(sl, buf);
+ } else
+ ret = strlist__add(sl, tev.event);
+ clear_probe_trace_event(&tev);
+ /* Skip if there is same name multi-probe event in the list */
+ if (ret == -EEXIST)
+ ret = 0;
+ if (ret < 0)
+ break;
+ }
+ strlist__delete(rawlist);
+
+ if (ret < 0) {
+ strlist__delete(sl);
+ return NULL;
+ }
+ return sl;
+}
+
+/* Get current perf-probe event names */
+struct strlist *probe_file__get_namelist(int fd)
+{
+ return __probe_file__get_namelist(fd, false);
+}
+
+int probe_file__add_event(int fd, struct probe_trace_event *tev)
+{
+ int ret = 0;
+ char *buf = synthesize_probe_trace_command(tev);
+ char sbuf[STRERR_BUFSIZE];
+
+ if (!buf) {
+ pr_debug("Failed to synthesize probe trace event.\n");
+ return -EINVAL;
+ }
+
+ pr_debug("Writing event: %s\n", buf);
+ if (!probe_event_dry_run) {
+ if (write(fd, buf, strlen(buf)) < (int)strlen(buf)) {
+ ret = -errno;
+ pr_warning("Failed to write event: %s\n",
+ str_error_r(errno, sbuf, sizeof(sbuf)));
+ }
+ }
+ free(buf);
+
+ return ret;
+}
+
+static int __del_trace_probe_event(int fd, struct str_node *ent)
+{
+ char *p;
+ char buf[128];
+ int ret;
+
+ /* Convert from perf-probe event to trace-probe event */
+ ret = e_snprintf(buf, 128, "-:%s", ent->s);
+ if (ret < 0)
+ goto error;
+
+ p = strchr(buf + 2, ':');
+ if (!p) {
+ pr_debug("Internal error: %s should have ':' but not.\n",
+ ent->s);
+ ret = -ENOTSUP;
+ goto error;
+ }
+ *p = '/';
+
+ pr_debug("Writing event: %s\n", buf);
+ ret = write(fd, buf, strlen(buf));
+ if (ret < 0) {
+ ret = -errno;
+ goto error;
+ }
+
+ return 0;
+error:
+ pr_warning("Failed to delete event: %s\n",
+ str_error_r(-ret, buf, sizeof(buf)));
+ return ret;
+}
+
+int probe_file__get_events(int fd, struct strfilter *filter,
+ struct strlist *plist)
+{
+ struct strlist *namelist;
+ struct str_node *ent;
+ const char *p;
+ int ret = -ENOENT;
+
+ if (!plist)
+ return -EINVAL;
+
+ namelist = __probe_file__get_namelist(fd, true);
+ if (!namelist)
+ return -ENOENT;
+
+ strlist__for_each_entry(ent, namelist) {
+ p = strchr(ent->s, ':');
+ if ((p && strfilter__compare(filter, p + 1)) ||
+ strfilter__compare(filter, ent->s)) {
+ ret = strlist__add(plist, ent->s);
+ if (ret == -ENOMEM) {
+ pr_err("strlist__add failed with -ENOMEM\n");
+ goto out;
+ }
+ ret = 0;
+ }
+ }
+out:
+ strlist__delete(namelist);
+
+ return ret;
+}
+
+int probe_file__del_strlist(int fd, struct strlist *namelist)
+{
+ int ret = 0;
+ struct str_node *ent;
+
+ strlist__for_each_entry(ent, namelist) {
+ ret = __del_trace_probe_event(fd, ent);
+ if (ret < 0)
+ break;
+ }
+ return ret;
+}
+
+int probe_file__del_events(int fd, struct strfilter *filter)
+{
+ struct strlist *namelist;
+ int ret;
+
+ namelist = strlist__new(NULL, NULL);
+ if (!namelist)
+ return -ENOMEM;
+
+ ret = probe_file__get_events(fd, filter, namelist);
+ if (ret < 0)
+ goto out;
+
+ ret = probe_file__del_strlist(fd, namelist);
+out:
+ strlist__delete(namelist);
+ return ret;
+}
+
+/* Caller must ensure to remove this entry from list */
+static void probe_cache_entry__delete(struct probe_cache_entry *entry)
+{
+ if (entry) {
+ BUG_ON(!list_empty(&entry->node));
+
+ strlist__delete(entry->tevlist);
+ clear_perf_probe_event(&entry->pev);
+ zfree(&entry->spev);
+ free(entry);
+ }
+}
+
+static struct probe_cache_entry *
+probe_cache_entry__new(struct perf_probe_event *pev)
+{
+ struct probe_cache_entry *entry = zalloc(sizeof(*entry));
+
+ if (entry) {
+ INIT_LIST_HEAD(&entry->node);
+ entry->tevlist = strlist__new(NULL, NULL);
+ if (!entry->tevlist)
+ zfree(&entry);
+ else if (pev) {
+ entry->spev = synthesize_perf_probe_command(pev);
+ if (!entry->spev ||
+ perf_probe_event__copy(&entry->pev, pev) < 0) {
+ probe_cache_entry__delete(entry);
+ return NULL;
+ }
+ }
+ }
+
+ return entry;
+}
+
+int probe_cache_entry__get_event(struct probe_cache_entry *entry,
+ struct probe_trace_event **tevs)
+{
+ struct probe_trace_event *tev;
+ struct str_node *node;
+ int ret, i;
+
+ ret = strlist__nr_entries(entry->tevlist);
+ if (ret > probe_conf.max_probes)
+ return -E2BIG;
+
+ *tevs = zalloc(ret * sizeof(*tev));
+ if (!*tevs)
+ return -ENOMEM;
+
+ i = 0;
+ strlist__for_each_entry(node, entry->tevlist) {
+ tev = &(*tevs)[i++];
+ ret = parse_probe_trace_command(node->s, tev);
+ if (ret < 0)
+ break;
+ }
+ return i;
+}
+
+/* For the kernel probe caches, pass target = NULL or DSO__NAME_KALLSYMS */
+static int probe_cache__open(struct probe_cache *pcache, const char *target,
+ struct nsinfo *nsi)
+{
+ char cpath[PATH_MAX];
+ char sbuildid[SBUILD_ID_SIZE];
+ char *dir_name = NULL;
+ bool is_kallsyms = false;
+ int ret, fd;
+ struct nscookie nsc;
+
+ if (target && build_id_cache__cached(target)) {
+ /* This is a cached buildid */
+ strlcpy(sbuildid, target, SBUILD_ID_SIZE);
+ dir_name = build_id_cache__linkname(sbuildid, NULL, 0);
+ goto found;
+ }
+
+ if (!target || !strcmp(target, DSO__NAME_KALLSYMS)) {
+ target = DSO__NAME_KALLSYMS;
+ is_kallsyms = true;
+ ret = sysfs__sprintf_build_id("/", sbuildid);
+ } else {
+ nsinfo__mountns_enter(nsi, &nsc);
+ ret = filename__sprintf_build_id(target, sbuildid);
+ nsinfo__mountns_exit(&nsc);
+ }
+
+ if (ret < 0) {
+ pr_debug("Failed to get build-id from %s.\n", target);
+ return ret;
+ }
+
+ /* If we have no buildid cache, make it */
+ if (!build_id_cache__cached(sbuildid)) {
+ ret = build_id_cache__add_s(sbuildid, target, nsi,
+ is_kallsyms, NULL);
+ if (ret < 0) {
+ pr_debug("Failed to add build-id cache: %s\n", target);
+ return ret;
+ }
+ }
+
+ dir_name = build_id_cache__cachedir(sbuildid, target, nsi, is_kallsyms,
+ false);
+found:
+ if (!dir_name) {
+ pr_debug("Failed to get cache from %s\n", target);
+ return -ENOMEM;
+ }
+
+ snprintf(cpath, PATH_MAX, "%s/probes", dir_name);
+ fd = open(cpath, O_CREAT | O_RDWR, 0644);
+ if (fd < 0)
+ pr_debug("Failed to open cache(%d): %s\n", fd, cpath);
+ free(dir_name);
+ pcache->fd = fd;
+
+ return fd;
+}
+
+static int probe_cache__load(struct probe_cache *pcache)
+{
+ struct probe_cache_entry *entry = NULL;
+ char buf[MAX_CMDLEN], *p;
+ int ret = 0, fddup;
+ FILE *fp;
+
+ fddup = dup(pcache->fd);
+ if (fddup < 0)
+ return -errno;
+ fp = fdopen(fddup, "r");
+ if (!fp) {
+ close(fddup);
+ return -EINVAL;
+ }
+
+ while (!feof(fp)) {
+ if (!fgets(buf, MAX_CMDLEN, fp))
+ break;
+ p = strchr(buf, '\n');
+ if (p)
+ *p = '\0';
+ /* #perf_probe_event or %sdt_event */
+ if (buf[0] == '#' || buf[0] == '%') {
+ entry = probe_cache_entry__new(NULL);
+ if (!entry) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ if (buf[0] == '%')
+ entry->sdt = true;
+ entry->spev = strdup(buf + 1);
+ if (entry->spev)
+ ret = parse_perf_probe_command(buf + 1,
+ &entry->pev);
+ else
+ ret = -ENOMEM;
+ if (ret < 0) {
+ probe_cache_entry__delete(entry);
+ goto out;
+ }
+ list_add_tail(&entry->node, &pcache->entries);
+ } else { /* trace_probe_event */
+ if (!entry) {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = strlist__add(entry->tevlist, buf);
+ if (ret == -ENOMEM) {
+ pr_err("strlist__add failed with -ENOMEM\n");
+ goto out;
+ }
+ }
+ }
+out:
+ fclose(fp);
+ return ret;
+}
+
+static struct probe_cache *probe_cache__alloc(void)
+{
+ struct probe_cache *pcache = zalloc(sizeof(*pcache));
+
+ if (pcache) {
+ INIT_LIST_HEAD(&pcache->entries);
+ pcache->fd = -EINVAL;
+ }
+ return pcache;
+}
+
+void probe_cache__purge(struct probe_cache *pcache)
+{
+ struct probe_cache_entry *entry, *n;
+
+ list_for_each_entry_safe(entry, n, &pcache->entries, node) {
+ list_del_init(&entry->node);
+ probe_cache_entry__delete(entry);
+ }
+}
+
+void probe_cache__delete(struct probe_cache *pcache)
+{
+ if (!pcache)
+ return;
+
+ probe_cache__purge(pcache);
+ if (pcache->fd > 0)
+ close(pcache->fd);
+ free(pcache);
+}
+
+struct probe_cache *probe_cache__new(const char *target, struct nsinfo *nsi)
+{
+ struct probe_cache *pcache = probe_cache__alloc();
+ int ret;
+
+ if (!pcache)
+ return NULL;
+
+ ret = probe_cache__open(pcache, target, nsi);
+ if (ret < 0) {
+ pr_debug("Cache open error: %d\n", ret);
+ goto out_err;
+ }
+
+ ret = probe_cache__load(pcache);
+ if (ret < 0) {
+ pr_debug("Cache read error: %d\n", ret);
+ goto out_err;
+ }
+
+ return pcache;
+
+out_err:
+ probe_cache__delete(pcache);
+ return NULL;
+}
+
+static bool streql(const char *a, const char *b)
+{
+ if (a == b)
+ return true;
+
+ if (!a || !b)
+ return false;
+
+ return !strcmp(a, b);
+}
+
+struct probe_cache_entry *
+probe_cache__find(struct probe_cache *pcache, struct perf_probe_event *pev)
+{
+ struct probe_cache_entry *entry = NULL;
+ char *cmd = synthesize_perf_probe_command(pev);
+
+ if (!cmd)
+ return NULL;
+
+ for_each_probe_cache_entry(entry, pcache) {
+ if (pev->sdt) {
+ if (entry->pev.event &&
+ streql(entry->pev.event, pev->event) &&
+ (!pev->group ||
+ streql(entry->pev.group, pev->group)))
+ goto found;
+
+ continue;
+ }
+ /* Hit if same event name or same command-string */
+ if ((pev->event &&
+ (streql(entry->pev.group, pev->group) &&
+ streql(entry->pev.event, pev->event))) ||
+ (!strcmp(entry->spev, cmd)))
+ goto found;
+ }
+ entry = NULL;
+
+found:
+ free(cmd);
+ return entry;
+}
+
+struct probe_cache_entry *
+probe_cache__find_by_name(struct probe_cache *pcache,
+ const char *group, const char *event)
+{
+ struct probe_cache_entry *entry = NULL;
+
+ for_each_probe_cache_entry(entry, pcache) {
+ /* Hit if same event name or same command-string */
+ if (streql(entry->pev.group, group) &&
+ streql(entry->pev.event, event))
+ goto found;
+ }
+ entry = NULL;
+
+found:
+ return entry;
+}
+
+int probe_cache__add_entry(struct probe_cache *pcache,
+ struct perf_probe_event *pev,
+ struct probe_trace_event *tevs, int ntevs)
+{
+ struct probe_cache_entry *entry = NULL;
+ char *command;
+ int i, ret = 0;
+
+ if (!pcache || !pev || !tevs || ntevs <= 0) {
+ ret = -EINVAL;
+ goto out_err;
+ }
+
+ /* Remove old cache entry */
+ entry = probe_cache__find(pcache, pev);
+ if (entry) {
+ list_del_init(&entry->node);
+ probe_cache_entry__delete(entry);
+ }
+
+ ret = -ENOMEM;
+ entry = probe_cache_entry__new(pev);
+ if (!entry)
+ goto out_err;
+
+ for (i = 0; i < ntevs; i++) {
+ if (!tevs[i].point.symbol)
+ continue;
+
+ command = synthesize_probe_trace_command(&tevs[i]);
+ if (!command)
+ goto out_err;
+ ret = strlist__add(entry->tevlist, command);
+ if (ret == -ENOMEM) {
+ pr_err("strlist__add failed with -ENOMEM\n");
+ goto out_err;
+ }
+
+ free(command);
+ }
+ list_add_tail(&entry->node, &pcache->entries);
+ pr_debug("Added probe cache: %d\n", ntevs);
+ return 0;
+
+out_err:
+ pr_debug("Failed to add probe caches\n");
+ probe_cache_entry__delete(entry);
+ return ret;
+}
+
+#ifdef HAVE_GELF_GETNOTE_SUPPORT
+static unsigned long long sdt_note__get_addr(struct sdt_note *note)
+{
+ return note->bit32 ?
+ (unsigned long long)note->addr.a32[SDT_NOTE_IDX_LOC] :
+ (unsigned long long)note->addr.a64[SDT_NOTE_IDX_LOC];
+}
+
+static unsigned long long sdt_note__get_ref_ctr_offset(struct sdt_note *note)
+{
+ return note->bit32 ?
+ (unsigned long long)note->addr.a32[SDT_NOTE_IDX_REFCTR] :
+ (unsigned long long)note->addr.a64[SDT_NOTE_IDX_REFCTR];
+}
+
+static const char * const type_to_suffix[] = {
+ ":s64", "", "", "", ":s32", "", ":s16", ":s8",
+ "", ":u8", ":u16", "", ":u32", "", "", "", ":u64"
+};
+
+/*
+ * Isolate the string number and convert it into a decimal value;
+ * this will be an index to get suffix of the uprobe name (defining
+ * the type)
+ */
+static int sdt_arg_parse_size(char *n_ptr, const char **suffix)
+{
+ long type_idx;
+
+ type_idx = strtol(n_ptr, NULL, 10);
+ if (type_idx < -8 || type_idx > 8) {
+ pr_debug4("Failed to get a valid sdt type\n");
+ return -1;
+ }
+
+ *suffix = type_to_suffix[type_idx + 8];
+ return 0;
+}
+
+static int synthesize_sdt_probe_arg(struct strbuf *buf, int i, const char *arg)
+{
+ char *op, *desc = strdup(arg), *new_op = NULL;
+ const char *suffix = "";
+ int ret = -1;
+
+ if (desc == NULL) {
+ pr_debug4("Allocation error\n");
+ return ret;
+ }
+
+ /*
+ * Argument is in N@OP format. N is size of the argument and OP is
+ * the actual assembly operand. N can be omitted; in that case
+ * argument is just OP(without @).
+ */
+ op = strchr(desc, '@');
+ if (op) {
+ op[0] = '\0';
+ op++;
+
+ if (sdt_arg_parse_size(desc, &suffix))
+ goto error;
+ } else {
+ op = desc;
+ }
+
+ ret = arch_sdt_arg_parse_op(op, &new_op);
+
+ if (ret < 0)
+ goto error;
+
+ if (ret == SDT_ARG_VALID) {
+ ret = strbuf_addf(buf, " arg%d=%s%s", i + 1, new_op, suffix);
+ if (ret < 0)
+ goto error;
+ }
+
+ ret = 0;
+error:
+ free(desc);
+ free(new_op);
+ return ret;
+}
+
+static char *synthesize_sdt_probe_command(struct sdt_note *note,
+ const char *pathname,
+ const char *sdtgrp)
+{
+ struct strbuf buf;
+ char *ret = NULL;
+ int i, args_count, err;
+ unsigned long long ref_ctr_offset;
+ char *arg;
+ int arg_idx = 0;
+
+ if (strbuf_init(&buf, 32) < 0)
+ return NULL;
+
+ err = strbuf_addf(&buf, "p:%s/%s %s:0x%llx",
+ sdtgrp, note->name, pathname,
+ sdt_note__get_addr(note));
+
+ ref_ctr_offset = sdt_note__get_ref_ctr_offset(note);
+ if (ref_ctr_offset && err >= 0)
+ err = strbuf_addf(&buf, "(0x%llx)", ref_ctr_offset);
+
+ if (err < 0)
+ goto error;
+
+ if (!note->args)
+ goto out;
+
+ if (note->args) {
+ char **args = argv_split(note->args, &args_count);
+
+ if (args == NULL)
+ goto error;
+
+ for (i = 0; i < args_count; ) {
+ /*
+ * FIXUP: Arm64 ELF section '.note.stapsdt' uses string
+ * format "-4@[sp, NUM]" if a probe is to access data in
+ * the stack, e.g. below is an example for the SDT
+ * Arguments:
+ *
+ * Arguments: -4@[sp, 12] -4@[sp, 8] -4@[sp, 4]
+ *
+ * Since the string introduces an extra space character
+ * in the middle of square brackets, the argument is
+ * divided into two items. Fixup for this case, if an
+ * item contains sub string "[sp,", need to concatenate
+ * the two items.
+ */
+ if (strstr(args[i], "[sp,") && (i+1) < args_count) {
+ err = asprintf(&arg, "%s %s", args[i], args[i+1]);
+ i += 2;
+ } else {
+ err = asprintf(&arg, "%s", args[i]);
+ i += 1;
+ }
+
+ /* Failed to allocate memory */
+ if (err < 0) {
+ argv_free(args);
+ goto error;
+ }
+
+ if (synthesize_sdt_probe_arg(&buf, arg_idx, arg) < 0) {
+ free(arg);
+ argv_free(args);
+ goto error;
+ }
+
+ free(arg);
+ arg_idx++;
+ }
+
+ argv_free(args);
+ }
+
+out:
+ ret = strbuf_detach(&buf, NULL);
+error:
+ strbuf_release(&buf);
+ return ret;
+}
+
+int probe_cache__scan_sdt(struct probe_cache *pcache, const char *pathname)
+{
+ struct probe_cache_entry *entry = NULL;
+ struct list_head sdtlist;
+ struct sdt_note *note;
+ char *buf;
+ char sdtgrp[64];
+ int ret;
+
+ INIT_LIST_HEAD(&sdtlist);
+ ret = get_sdt_note_list(&sdtlist, pathname);
+ if (ret < 0) {
+ pr_debug4("Failed to get sdt note: %d\n", ret);
+ return ret;
+ }
+ list_for_each_entry(note, &sdtlist, note_list) {
+ ret = snprintf(sdtgrp, 64, "sdt_%s", note->provider);
+ if (ret < 0)
+ break;
+ /* Try to find same-name entry */
+ entry = probe_cache__find_by_name(pcache, sdtgrp, note->name);
+ if (!entry) {
+ entry = probe_cache_entry__new(NULL);
+ if (!entry) {
+ ret = -ENOMEM;
+ break;
+ }
+ entry->sdt = true;
+ ret = asprintf(&entry->spev, "%s:%s=%s", sdtgrp,
+ note->name, note->name);
+ if (ret < 0)
+ break;
+ entry->pev.event = strdup(note->name);
+ entry->pev.group = strdup(sdtgrp);
+ list_add_tail(&entry->node, &pcache->entries);
+ }
+ buf = synthesize_sdt_probe_command(note, pathname, sdtgrp);
+ if (!buf) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ ret = strlist__add(entry->tevlist, buf);
+
+ free(buf);
+ entry = NULL;
+
+ if (ret == -ENOMEM) {
+ pr_err("strlist__add failed with -ENOMEM\n");
+ break;
+ }
+ }
+ if (entry) {
+ list_del_init(&entry->node);
+ probe_cache_entry__delete(entry);
+ }
+ cleanup_sdt_note_list(&sdtlist);
+ return ret;
+}
+#endif
+
+static int probe_cache_entry__write(struct probe_cache_entry *entry, int fd)
+{
+ struct str_node *snode;
+ struct stat st;
+ struct iovec iov[3];
+ const char *prefix = entry->sdt ? "%" : "#";
+ int ret;
+ /* Save stat for rollback */
+ ret = fstat(fd, &st);
+ if (ret < 0)
+ return ret;
+
+ pr_debug("Writing cache: %s%s\n", prefix, entry->spev);
+ iov[0].iov_base = (void *)prefix; iov[0].iov_len = 1;
+ iov[1].iov_base = entry->spev; iov[1].iov_len = strlen(entry->spev);
+ iov[2].iov_base = (void *)"\n"; iov[2].iov_len = 1;
+ ret = writev(fd, iov, 3);
+ if (ret < (int)iov[1].iov_len + 2)
+ goto rollback;
+
+ strlist__for_each_entry(snode, entry->tevlist) {
+ iov[0].iov_base = (void *)snode->s;
+ iov[0].iov_len = strlen(snode->s);
+ iov[1].iov_base = (void *)"\n"; iov[1].iov_len = 1;
+ ret = writev(fd, iov, 2);
+ if (ret < (int)iov[0].iov_len + 1)
+ goto rollback;
+ }
+ return 0;
+
+rollback:
+ /* Rollback to avoid cache file corruption */
+ if (ret > 0)
+ ret = -1;
+ if (ftruncate(fd, st.st_size) < 0)
+ ret = -2;
+
+ return ret;
+}
+
+int probe_cache__commit(struct probe_cache *pcache)
+{
+ struct probe_cache_entry *entry;
+ int ret = 0;
+
+ /* TBD: if we do not update existing entries, skip it */
+ ret = lseek(pcache->fd, 0, SEEK_SET);
+ if (ret < 0)
+ goto out;
+
+ ret = ftruncate(pcache->fd, 0);
+ if (ret < 0)
+ goto out;
+
+ for_each_probe_cache_entry(entry, pcache) {
+ ret = probe_cache_entry__write(entry, pcache->fd);
+ pr_debug("Cache committed: %d\n", ret);
+ if (ret < 0)
+ break;
+ }
+out:
+ return ret;
+}
+
+static bool probe_cache_entry__compare(struct probe_cache_entry *entry,
+ struct strfilter *filter)
+{
+ char buf[128], *ptr = entry->spev;
+
+ if (entry->pev.event) {
+ snprintf(buf, 128, "%s:%s", entry->pev.group, entry->pev.event);
+ ptr = buf;
+ }
+ return strfilter__compare(filter, ptr);
+}
+
+int probe_cache__filter_purge(struct probe_cache *pcache,
+ struct strfilter *filter)
+{
+ struct probe_cache_entry *entry, *tmp;
+
+ list_for_each_entry_safe(entry, tmp, &pcache->entries, node) {
+ if (probe_cache_entry__compare(entry, filter)) {
+ pr_info("Removed cached event: %s\n", entry->spev);
+ list_del_init(&entry->node);
+ probe_cache_entry__delete(entry);
+ }
+ }
+ return 0;
+}
+
+static int probe_cache__show_entries(struct probe_cache *pcache,
+ struct strfilter *filter)
+{
+ struct probe_cache_entry *entry;
+
+ for_each_probe_cache_entry(entry, pcache) {
+ if (probe_cache_entry__compare(entry, filter))
+ printf("%s\n", entry->spev);
+ }
+ return 0;
+}
+
+/* Show all cached probes */
+int probe_cache__show_all_caches(struct strfilter *filter)
+{
+ struct probe_cache *pcache;
+ struct strlist *bidlist;
+ struct str_node *nd;
+ char *buf = strfilter__string(filter);
+
+ pr_debug("list cache with filter: %s\n", buf);
+ free(buf);
+
+ bidlist = build_id_cache__list_all(true);
+ if (!bidlist) {
+ pr_debug("Failed to get buildids: %d\n", errno);
+ return -EINVAL;
+ }
+ strlist__for_each_entry(nd, bidlist) {
+ pcache = probe_cache__new(nd->s, NULL);
+ if (!pcache)
+ continue;
+ if (!list_empty(&pcache->entries)) {
+ buf = build_id_cache__origname(nd->s);
+ printf("%s (%s):\n", buf, nd->s);
+ free(buf);
+ probe_cache__show_entries(pcache, filter);
+ }
+ probe_cache__delete(pcache);
+ }
+ strlist__delete(bidlist);
+
+ return 0;
+}
+
+enum ftrace_readme {
+ FTRACE_README_PROBE_TYPE_X = 0,
+ FTRACE_README_KRETPROBE_OFFSET,
+ FTRACE_README_UPROBE_REF_CTR,
+ FTRACE_README_USER_ACCESS,
+ FTRACE_README_MULTIPROBE_EVENT,
+ FTRACE_README_IMMEDIATE_VALUE,
+ FTRACE_README_END,
+};
+
+static struct {
+ const char *pattern;
+ bool avail;
+} ftrace_readme_table[] = {
+#define DEFINE_TYPE(idx, pat) \
+ [idx] = {.pattern = pat, .avail = false}
+ DEFINE_TYPE(FTRACE_README_PROBE_TYPE_X, "*type: * x8/16/32/64,*"),
+ DEFINE_TYPE(FTRACE_README_KRETPROBE_OFFSET, "*place (kretprobe): *"),
+ DEFINE_TYPE(FTRACE_README_UPROBE_REF_CTR, "*ref_ctr_offset*"),
+ DEFINE_TYPE(FTRACE_README_USER_ACCESS, "*u]<offset>*"),
+ DEFINE_TYPE(FTRACE_README_MULTIPROBE_EVENT, "*Create/append/*"),
+ DEFINE_TYPE(FTRACE_README_IMMEDIATE_VALUE, "*\\imm-value,*"),
+};
+
+static bool scan_ftrace_readme(enum ftrace_readme type)
+{
+ int fd;
+ FILE *fp;
+ char *buf = NULL;
+ size_t len = 0;
+ bool ret = false;
+ static bool scanned = false;
+
+ if (scanned)
+ goto result;
+
+ fd = open_trace_file("README", false);
+ if (fd < 0)
+ return ret;
+
+ fp = fdopen(fd, "r");
+ if (!fp) {
+ close(fd);
+ return ret;
+ }
+
+ while (getline(&buf, &len, fp) > 0)
+ for (enum ftrace_readme i = 0; i < FTRACE_README_END; i++)
+ if (!ftrace_readme_table[i].avail)
+ ftrace_readme_table[i].avail =
+ strglobmatch(buf, ftrace_readme_table[i].pattern);
+ scanned = true;
+
+ fclose(fp);
+ free(buf);
+
+result:
+ if (type >= FTRACE_README_END)
+ return false;
+
+ return ftrace_readme_table[type].avail;
+}
+
+bool probe_type_is_available(enum probe_type type)
+{
+ if (type >= PROBE_TYPE_END)
+ return false;
+ else if (type == PROBE_TYPE_X)
+ return scan_ftrace_readme(FTRACE_README_PROBE_TYPE_X);
+
+ return true;
+}
+
+bool kretprobe_offset_is_supported(void)
+{
+ return scan_ftrace_readme(FTRACE_README_KRETPROBE_OFFSET);
+}
+
+bool uprobe_ref_ctr_is_supported(void)
+{
+ return scan_ftrace_readme(FTRACE_README_UPROBE_REF_CTR);
+}
+
+bool user_access_is_supported(void)
+{
+ return scan_ftrace_readme(FTRACE_README_USER_ACCESS);
+}
+
+bool multiprobe_event_is_supported(void)
+{
+ return scan_ftrace_readme(FTRACE_README_MULTIPROBE_EVENT);
+}
+
+bool immediate_value_is_supported(void)
+{
+ return scan_ftrace_readme(FTRACE_README_IMMEDIATE_VALUE);
+}