Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965298Ab3HIIpj (ORCPT ); Fri, 9 Aug 2013 04:45:39 -0400 Received: from lgeamrelo01.lge.com ([156.147.1.125]:48724 "EHLO LGEAMRELO01.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965100Ab3HIIpb (ORCPT ); Fri, 9 Aug 2013 04:45:31 -0400 X-AuditID: 9c93017d-b7cdfae0000026c0-bc-5204ac18a54b From: Namhyung Kim To: Steven Rostedt Cc: Namhyung Kim , Hyeoncheol Lee , Masami Hiramatsu , LKML , Srikar Dronamraju , Oleg Nesterov , "zhangwei(Jovi)" , Arnaldo Carvalho de Melo Subject: [PATCH 13/13] tracing/uprobes: Add support for full argument access methods Date: Fri, 9 Aug 2013 17:45:09 +0900 Message-Id: <1376037909-17797-14-git-send-email-namhyung@kernel.org> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1376037909-17797-1-git-send-email-namhyung@kernel.org> References: <1376037909-17797-1-git-send-email-namhyung@kernel.org> X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3764 Lines: 111 From: Namhyung Kim Enable to fetch other types of argument for the uprobes. IOW, we can access stack, memory, deref, bitfield and retval from uprobes now. Original-patch-by: Hyeoncheol Lee Cc: Masami Hiramatsu Cc: Srikar Dronamraju Cc: Oleg Nesterov Cc: zhangwei(Jovi) Cc: Arnaldo Carvalho de Melo Signed-off-by: Namhyung Kim --- kernel/trace/trace_probe.c | 34 ++++++++++++++++++++-------------- 1 file changed, 20 insertions(+), 14 deletions(-) diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 70cd3bfde5a6..b68ceb7cad6e 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -253,7 +253,7 @@ fail: } /* Special function : only accept unsigned long */ -static __kprobes void fetch_stack_address(struct pt_regs *regs, +static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs, void *dummy, void *dest, void *priv) { *(unsigned long *)dest = kernel_stack_pointer(regs); @@ -303,7 +303,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset) #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) static int parse_probe_vars(char *arg, const struct fetch_type *t, - struct fetch_param *f, bool is_return) + struct fetch_param *f, bool is_return, + bool is_kprobe) { int ret = 0; unsigned long param; @@ -315,13 +316,18 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, ret = -EINVAL; } else if (strncmp(arg, "stack", 5) == 0) { if (arg[5] == '\0') { - if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0) - f->fn = fetch_stack_address; - else - ret = -EINVAL; + if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR)) + return -EINVAL; + + if (is_kprobe) + f->fn = fetch_kernel_stack_address; + else { + f->fn = t->fetch[FETCH_MTD_stack]; + f->data = (void *)0; + } } else if (isdigit(arg[5])) { ret = kstrtoul(arg + 5, 10, ¶m); - if (ret || param > PARAM_MAX_STACK) + if (ret || (is_kprobe && param > PARAM_MAX_STACK)) ret = -EINVAL; else { f->fn = t->fetch[FETCH_MTD_stack]; @@ -345,17 +351,13 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, int ret; const struct fetch_type *ttbl; - ttbl = kprobes_fetch_type_table; + ttbl = is_kprobe ? kprobes_fetch_type_table : uprobes_fetch_type_table; ret = 0; - /* Until uprobe_events supports only reg arguments */ - if (!is_kprobe && arg[0] != '%') - return -EINVAL; - switch (arg[0]) { case '$': - ret = parse_probe_vars(arg + 1, t, f, is_return); + ret = parse_probe_vars(arg + 1, t, f, is_return, is_kprobe); break; case '%': /* named register */ @@ -376,6 +378,10 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, f->fn = t->fetch[FETCH_MTD_memory]; f->data = (void *)param; } else { + /* uprobes don't support symbols */ + if (!is_kprobe) + return -EINVAL; + ret = traceprobe_split_symbol_offset(arg + 1, &offset); if (ret) break; @@ -482,7 +488,7 @@ int traceprobe_parse_probe_arg(char *arg, ssize_t *size, int ret; const struct fetch_type *ttbl; - ttbl = kprobes_fetch_type_table; + ttbl = is_kprobe ? kprobes_fetch_type_table : uprobes_fetch_type_table; if (strlen(arg) > MAX_ARGSTR_LEN) { pr_info("Argument is too long.: %s\n", arg); -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/