From 8f0d098bc0b14f00c4d6ea3f48809626fa1c416f Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Thu, 28 Jul 2011 18:45:37 -0400 Subject: [PATCH] Add kretprobe support (new --function implementation) Add kretprobe support (new --function implementation) Also support probe "symbol" (without +offset) by checking first character with isalpha(). Signed-off-by: Mathieu Desnoyers --- include/lttng-kernel.h | 9 ++++++ include/lttng/lttng.h | 1 + ltt-sessiond/ltt-sessiond.h | 1 + ltt-sessiond/trace.c | 8 +++++ lttng/commands/enable_events.c | 58 +++++++++++++++++++++++++++------- 5 files changed, 66 insertions(+), 11 deletions(-) diff --git a/include/lttng-kernel.h b/include/lttng-kernel.h index 2d88012b0..9eb207bb2 100644 --- a/include/lttng-kernel.h +++ b/include/lttng-kernel.h @@ -35,6 +35,7 @@ enum lttng_kernel_instrumentation { LTTNG_KERNEL_TRACEPOINT = 0, LTTNG_KERNEL_KPROBE = 1, LTTNG_KERNEL_FUNCTION = 2, + LTTNG_KERNEL_KRETPROBE = 3, }; enum lttng_kernel_context_type { @@ -65,6 +66,13 @@ struct lttng_kernel_context { } u; }; +struct lttng_kernel_kretprobe { + uint64_t addr; + + uint64_t offset; + char symbol_name[LTTNG_SYM_NAME_LEN]; +}; + /* * Either addr is used, or symbol_name and offset. */ @@ -85,6 +93,7 @@ struct lttng_kernel_event { enum lttng_kernel_instrumentation instrumentation; /* Per instrumentation type configuration */ union { + struct lttng_kernel_kretprobe kretprobe; struct lttng_kernel_kprobe kprobe; struct lttng_kernel_function ftrace; } u; diff --git a/include/lttng/lttng.h b/include/lttng/lttng.h index b5f754082..2cbb7f7ed 100644 --- a/include/lttng/lttng.h +++ b/include/lttng/lttng.h @@ -73,6 +73,7 @@ enum lttng_event_type { LTTNG_EVENT_TRACEPOINT, LTTNG_EVENT_PROBE, LTTNG_EVENT_FUNCTION, + LTTNG_EVENT_FUNCTION_ENTRY, }; /* diff --git a/ltt-sessiond/ltt-sessiond.h b/ltt-sessiond/ltt-sessiond.h index c2ff58ab6..17c9c32f8 100644 --- a/ltt-sessiond/ltt-sessiond.h +++ b/ltt-sessiond/ltt-sessiond.h @@ -36,6 +36,7 @@ const char *kernel_modules_list[] = { "ltt-ring-buffer-metadata-mmap-client", "lttng-ftrace", "lttng-kprobes", + "lttng-kretprobes", "lttng-probe-block", "lttng-probe-irq", "lttng-probe-kvm", diff --git a/ltt-sessiond/trace.c b/ltt-sessiond/trace.c index 41c4355e9..c090f2106 100644 --- a/ltt-sessiond/trace.c +++ b/ltt-sessiond/trace.c @@ -185,6 +185,14 @@ struct ltt_kernel_event *trace_create_kernel_event(struct lttng_event *ev) ev->attr.probe.symbol_name, LTTNG_SYM_NAME_LEN); break; case LTTNG_EVENT_FUNCTION: + attr->instrumentation = LTTNG_KERNEL_KRETPROBE; + attr->u.kretprobe.addr = ev->attr.probe.addr; + attr->u.kretprobe.offset = ev->attr.probe.offset; + attr->u.kretprobe.offset = ev->attr.probe.offset; + strncpy(attr->u.kretprobe.symbol_name, + ev->attr.probe.symbol_name, LTTNG_SYM_NAME_LEN); + break; + case LTTNG_EVENT_FUNCTION_ENTRY: attr->instrumentation = LTTNG_KERNEL_FUNCTION; strncpy(attr->u.ftrace.symbol_name, ev->attr.ftrace.symbol_name, LTTNG_SYM_NAME_LEN); diff --git a/lttng/commands/enable_events.c b/lttng/commands/enable_events.c index 5d025e708..b99b7f4c9 100644 --- a/lttng/commands/enable_events.c +++ b/lttng/commands/enable_events.c @@ -25,6 +25,7 @@ #include #include #include +#include #include "../cmd.h" #include "../conf.h" @@ -40,7 +41,8 @@ static int opt_userspace; static int opt_enable_all; static pid_t opt_pid; static char *opt_probe; -static char *opt_function_symbol; +static char *opt_function; +static char *opt_function_entry_symbol; static char *opt_channel_name; enum { @@ -50,6 +52,7 @@ enum { OPT_MARKER, OPT_PROBE, OPT_FUNCTION, + OPT_FUNCTION_ENTRY, }; static struct poptOption long_options[] = { @@ -66,6 +69,7 @@ static struct poptOption long_options[] = { {"marker", 0, POPT_ARG_NONE, 0, OPT_MARKER, 0, 0}, {"probe", 0, POPT_ARG_STRING, 0, OPT_PROBE, 0, 0}, {"function", 0, POPT_ARG_STRING, 0, OPT_FUNCTION, 0, 0}, + {"function:entry", 0, POPT_ARG_STRING, 0, OPT_FUNCTION_ENTRY, 0, 0}, {0, 0, 0, 0, 0, 0, 0} }; @@ -87,11 +91,16 @@ static void usage(FILE *ofp) fprintf(ofp, "\n"); fprintf(ofp, "Event options:\n"); fprintf(ofp, " --tracepoint Tracepoint event (default)\n"); - fprintf(ofp, " --probe [addr | symbol+offset]\n"); + fprintf(ofp, " --probe [addr | symbol | symbol+offset]\n"); fprintf(ofp, " Dynamic probe.\n"); fprintf(ofp, " Addr and offset can be octal (0NNN...),\n"); fprintf(ofp, " decimal (NNN...) or hexadecimal (0xNNN...)\n"); - fprintf(ofp, " --function SYMBOL Function tracer event\n"); + fprintf(ofp, " --function [addr | symbol | symbol+offset]\n"); + fprintf(ofp, " Dynamic function entry/return probe.\n"); + fprintf(ofp, " Addr and offset can be octal (0NNN...),\n"); + fprintf(ofp, " decimal (NNN...) or hexadecimal (0xNNN...)\n"); + fprintf(ofp, " --function:entry symbol\n"); + fprintf(ofp, " Function tracer event\n"); fprintf(ofp, " --marker User-space marker (deprecated)\n"); fprintf(ofp, "\n"); } @@ -109,7 +118,7 @@ static int parse_probe_opts(struct lttng_event *ev, char *opt) if (opt == NULL) { ret = -1; - goto error; + goto end; } /* Check for symbol+offset */ @@ -120,12 +129,25 @@ static int parse_probe_opts(struct lttng_event *ev, char *opt) if (strlen(s_hex) == 0) { ERR("Invalid probe offset %s", s_hex); ret = -1; - goto error; + goto end; } ev->attr.probe.offset = strtoul(s_hex, NULL, 0); DBG("probe offset %" PRIu64, ev->attr.probe.offset); ev->attr.probe.addr = 0; - goto error; + goto end; + } + + /* Check for symbol */ + if (isalpha(name[0])) { + ret = sscanf(opt, "%s", name); + if (ret == 1) { + strncpy(ev->attr.probe.symbol_name, name, LTTNG_SYMBOL_NAME_LEN); + DBG("probe symbol %s", ev->attr.probe.symbol_name); + ev->attr.probe.offset = 0; + DBG("probe offset %" PRIu64, ev->attr.probe.offset); + ev->attr.probe.addr = 0; + goto end; + } } /* Check for address */ @@ -134,19 +156,19 @@ static int parse_probe_opts(struct lttng_event *ev, char *opt) if (strlen(s_hex) == 0) { ERR("Invalid probe address %s", s_hex); ret = -1; - goto error; + goto end; } ev->attr.probe.addr = strtoul(s_hex, NULL, 0); DBG("probe addr %" PRIu64, ev->attr.probe.addr); ev->attr.probe.offset = 0; memset(ev->attr.probe.symbol_name, 0, LTTNG_SYMBOL_NAME_LEN); - goto error; + goto end; } /* No match */ ret = -1; -error: +end: return ret; } @@ -222,7 +244,17 @@ static int enable_events(void) } break; case LTTNG_EVENT_FUNCTION: - strncpy(ev.attr.ftrace.symbol_name, opt_function_symbol, LTTNG_SYMBOL_NAME_LEN); + ret = parse_probe_opts(&ev, opt_function); + if (ret < 0) { + ERR("Unable to parse function probe options"); + ret = 0; + goto error; + } + break; + case LTTNG_EVENT_FUNCTION_ENTRY: + strncpy(ev.attr.ftrace.symbol_name, + opt_function_entry_symbol, + LTTNG_SYMBOL_NAME_LEN); break; default: ret = CMD_NOT_IMPLEMENTED; @@ -296,7 +328,11 @@ int cmd_enable_events(int argc, const char **argv) break; case OPT_FUNCTION: opt_event_type = LTTNG_EVENT_FUNCTION; - opt_function_symbol = poptGetOptArg(pc); + opt_function = poptGetOptArg(pc); + break; + case OPT_FUNCTION_ENTRY: + opt_event_type = LTTNG_EVENT_FUNCTION_ENTRY; + opt_function_entry_symbol = poptGetOptArg(pc); break; default: usage(stderr); -- 2.34.1