Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755908AbZGGFwl (ORCPT ); Tue, 7 Jul 2009 01:52:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753246AbZGGFwd (ORCPT ); Tue, 7 Jul 2009 01:52:33 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:61129 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753940AbZGGFwc (ORCPT ); Tue, 7 Jul 2009 01:52:32 -0400 Message-ID: <4A52E2A4.4050007@cn.fujitsu.com> Date: Tue, 07 Jul 2009 13:52:36 +0800 From: Li Zefan User-Agent: Thunderbird 2.0.0.9 (X11/20071115) MIME-Version: 1.0 To: Ingo Molnar CC: "K.Prasad" , Alan Stern , Frederic Weisbecker , Steven Rostedt , LKML Subject: [PATCH 1/8] ksym_tracer: Extract trace entry from struct trace_ksym References: <4A52E291.1020408@cn.fujitsu.com> In-Reply-To: <4A52E291.1020408@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4034 Lines: 126 struct trace_ksym is used as an entry in hbp list, and is also used as trace_entry stored in ring buffer. This is not necessary and is a waste of memory in ring buffer. There is also a bug that dereferencing field->ksym_hbp in ksym_trace_output() can be invalid. Signed-off-by: Li Zefan --- kernel/trace/trace.h | 13 ++++--------- kernel/trace/trace_ksym.c | 26 ++++++++++++++++++-------- 2 files changed, 22 insertions(+), 17 deletions(-) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 61b4e94..6868902 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -215,17 +215,12 @@ struct syscall_trace_exit { #define KSYM_SELFTEST_ENTRY "ksym_selftest_dummy" extern int process_new_ksym_entry(char *ksymname, int op, unsigned long addr); -struct trace_ksym { +struct ksym_trace_entry { struct trace_entry ent; - struct hw_breakpoint *ksym_hbp; - unsigned long ksym_addr; unsigned long ip; -#ifdef CONFIG_PROFILE_KSYM_TRACER - unsigned long counter; -#endif - struct hlist_node ksym_hlist; + unsigned char type; char ksym_name[KSYM_NAME_LEN]; - char p_name[TASK_COMM_LEN]; + char cmd[TASK_COMM_LEN]; }; /* @@ -343,7 +338,7 @@ extern void __ftrace_bad_type(void); TRACE_SYSCALL_ENTER); \ IF_ASSIGN(var, ent, struct syscall_trace_exit, \ TRACE_SYSCALL_EXIT); \ - IF_ASSIGN(var, ent, struct trace_ksym, TRACE_KSYM); \ + IF_ASSIGN(var, ent, struct ksym_trace_entry, TRACE_KSYM);\ __ftrace_bad_type(); \ } while (0) diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c index eef97e7..085ff05 100644 --- a/kernel/trace/trace_ksym.c +++ b/kernel/trace/trace_ksym.c @@ -37,6 +37,15 @@ #define KSYM_TRACER_OP_LEN 3 /* rw- */ #define KSYM_FILTER_ENTRY_LEN (KSYM_NAME_LEN + KSYM_TRACER_OP_LEN + 1) +struct trace_ksym { + struct hw_breakpoint *ksym_hbp; + unsigned long ksym_addr; +#ifdef CONFIG_PROFILE_KSYM_TRACER + unsigned long counter; +#endif + struct hlist_node ksym_hlist; +}; + static struct trace_array *ksym_trace_array; static unsigned int ksym_filter_entry_count; @@ -71,7 +80,7 @@ void ksym_hbp_handler(struct hw_breakpoint *hbp, struct pt_regs *regs) { struct ring_buffer_event *event; struct trace_array *tr; - struct trace_ksym *entry; + struct ksym_trace_entry *entry; int pc; if (!ksym_tracing_enabled) @@ -85,11 +94,12 @@ void ksym_hbp_handler(struct hw_breakpoint *hbp, struct pt_regs *regs) if (!event) return; - entry = ring_buffer_event_data(event); + entry = ring_buffer_event_data(event); + entry->ip = instruction_pointer(regs); + entry->type = hbp->info.type; strlcpy(entry->ksym_name, hbp->info.name, KSYM_SYMBOL_LEN); - entry->ksym_hbp = hbp; - entry->ip = instruction_pointer(regs); - strlcpy(entry->p_name, current->comm, TASK_COMM_LEN); + strlcpy(entry->cmd, current->comm, TASK_COMM_LEN); + #ifdef CONFIG_PROFILE_KSYM_TRACER ksym_collect_stats(hbp->info.address); #endif /* CONFIG_PROFILE_KSYM_TRACER */ @@ -380,7 +390,7 @@ static enum print_line_t ksym_trace_output(struct trace_iterator *iter) { struct trace_entry *entry = iter->ent; struct trace_seq *s = &iter->seq; - struct trace_ksym *field; + struct ksym_trace_entry *field; char str[KSYM_SYMBOL_LEN]; int ret; @@ -389,12 +399,12 @@ static enum print_line_t ksym_trace_output(struct trace_iterator *iter) trace_assign_type(field, entry); - ret = trace_seq_printf(s, "%-15s %-5d %-3d %-20s ", field->p_name, + ret = trace_seq_printf(s, "%-15s %-5d %-3d %-20s ", field->cmd, entry->pid, iter->cpu, field->ksym_name); if (!ret) return TRACE_TYPE_PARTIAL_LINE; - switch (field->ksym_hbp->info.type) { + switch (field->type) { case HW_BREAKPOINT_WRITE: ret = trace_seq_printf(s, " W "); break; -- 1.5.4.rc3 -- 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/