From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28053 invoked by alias); 14 Aug 2013 04:27:07 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 28036 invoked by uid 89); 14 Aug 2013 04:27:06 -0000 X-Spam-SWARE-Status: No, score=-0.9 required=5.0 tests=BAYES_00,MSGID_MULTIPLE_AT,SPF_PASS autolearn=no version=3.3.2 Received: from out524-80.mail.aliyun.com (HELO out524-80.mail.aliyun.com) (42.121.24.80) by sourceware.org (qpsmtpd/0.84/v0.84-167-ge50287c) with ESMTP; Wed, 14 Aug 2013 04:27:04 +0000 Received: from ALIYUN032621(182.92.247.1) by smtp.aliyun-inc.com(127.0.0.1); Wed, 14 Aug 2013 12:27:00 +0800 From: "Will Huang" To: Cc: "'Will Huang'" Subject: [PATCH][PR threads/15824] when get threads name failed from info threads with linux kernel version earlier than 2.6.33 Date: Wed, 14 Aug 2013 04:27:00 -0000 Message-ID: <00b201ce98a6$7cf69150$76e3b3f0$@huang@aliyun-inc.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-SW-Source: 2013-08/txt/msg00369.txt.bz2 Test OS:Linux 2.6.32-220.23.2.ali1089.el5.x86_64 GNU gdb (GDB) 7.6 Under linux kernel 2.6.32( or earlier version) there is no proc file named /proc/$pid/task/$tid/comm. GDB init their threads' name from this proc file. So info threads can't print correct thread names when This proc file not exist. This can be solve by using procfs /proc/$pid/task/$tid/status instead if comm file not exists. Status file has a Name line which starts by "Name:". diff -ruN ./gdb.org/ChangeLog ./gdb/ChangeLog --- ./gdb.org/ChangeLog 2013-04-26 19:43:30.000000000 +0800 +++ ./gdb/ChangeLog 2013-08-14 11:09:08.000000000 +0800 @@ -1,3 +1,11 @@ +2013-08-14 Will Huang + + PR threads/15824 + * linux-nat.c (linux_nat_thread_name): Add get thread name from + procfs "/proc/$pid/task/$tid/status". + * commo/linux-procfs.c (linux_proc_get_thread_name): New. + * commo/linux-procfs.c (linux_proc_get_string): New. + 2013-04-26 Joel Brobecker * NEWS: Change "since GDB 7.5" into "in GDB 7.6". diff -ruN ./gdb.org/common/linux-procfs.c ./gdb/common/linux-procfs.c --- ./gdb.org/common/linux-procfs.c 2013-01-01 14:32:54.000000000 +0800 +++ ./gdb/common/linux-procfs.c 2013-08-12 16:51:33.000000000 +0800 @@ -55,6 +55,51 @@ return retval; } +/* Return the string length of Name from /proc/$pid/task/$tid/status. + Returns -1 if not found. */ + +static int +linux_proc_get_string (pid_t lwpid, pid_t tid, + char *target, size_t t_size, const char *field) +{ + size_t field_len = strlen (field); + FILE *status_file; + char buf[100]; + int retval = -1; + + if (tid > 0) + snprintf (buf, sizeof (buf), + "/proc/%d/task/%d/status", (int) lwpid, (int) tid); + else + snprintf (buf, sizeof (buf), "/proc/%d/status", (int) lwpid); + + status_file = fopen (buf, "r"); + if (status_file == NULL) + { + warning (_("unable to open /proc file '%s'"), buf); + return -1; + } + + while (fgets (buf, sizeof (buf), status_file)) + if (strncmp (buf, field, field_len) == 0 && buf[field_len] == ':') + { + size_t pos = field_len + 1; + while((buf[pos] == ' ' || buf[pos] == '\t') && (pos < sizeof (buf) - 1)) + pos++; + + strncpy (target, &buf[pos], t_size); + target[t_size - 1] = '\0'; + retval = strlen (target); + if(retval > 0 && target[retval - 1] == '\n') + target[retval - 1] = '\0'; + + break; + } + + fclose (status_file); + return retval; +} + /* Return the TGID of LWPID from /proc/pid/status. Returns -1 if not found. */ @@ -118,3 +163,11 @@ { return linux_proc_pid_has_state (pid, "Z (zombie)"); } + +/*Get thread name identified by PID & TID*/ + +int +linux_proc_get_thread_name (pid_t pid, pid_t tid, char *name, size_t size) +{ + return linux_proc_get_string (pid, tid, name, size, "Name"); +} diff -ruN ./gdb.org/common/linux-procfs.h ./gdb/common/linux-procfs.h --- ./gdb.org/common/linux-procfs.h 2013-01-01 14:32:54.000000000 +0800 +++ ./gdb/common/linux-procfs.h 2013-08-12 16:50:39.000000000 +0800 @@ -40,4 +40,10 @@ extern int linux_proc_pid_is_zombie (pid_t pid); +/* Return -1 if thread Name of tid didn't found; + "char *name" for thread name (need be allocated by caller). */ + +extern int linux_proc_get_thread_name (pid_t pid, pid_t tid, + char *name, size_t size); + #endif /* COMMON_LINUX_PROCFS_H */ diff -ruN ./gdb.org/linux-nat.c ./gdb/linux-nat.c --- ./gdb.org/linux-nat.c 2013-02-13 22:59:49.000000000 +0800 +++ ./gdb/linux-nat.c 2013-08-12 16:47:26.000000000 +0800 @@ -4294,6 +4294,14 @@ fclose (comm_file); } + else + { + static char comm[COMM_LEN + 1]; + int size = linux_proc_get_thread_name (pid, lwp, comm, COMM_LEN+1); + if (size > 0) + result = comm; + + } #undef COMM_LEN #undef FORMAT diff -ruN ./gdb.org/testsuite/ChangeLog ./gdb/testsuite/ChangeLog --- ./gdb.org/testsuite/ChangeLog 2013-04-25 20:22:26.000000000 +0800 +++ ./gdb/testsuite/ChangeLog 2013-08-14 12:18:23.000000000 +0800 @@ -1,3 +1,9 @@ +2013-08-14 Will Huang + + PR threads/15824 + * gdb.threads/manythreads.exp: Add test for get thread + original name + 2013-04-25 Sergio Durigan Junior * gdb.arch/arm-bl-branch-dest.c: New file. diff -ruN ./gdb.org/testsuite/gdb.threads/manythreads.exp ./gdb/testsuite/gdb.threads/manythreads.exp --- ./gdb.org/testsuite/gdb.threads/manythreads.exp 2013-01-01 14:41:27.000000000 +0800 +++ ./gdb/testsuite/gdb.threads/manythreads.exp 2013-08-14 12:15:07.000000000 +0800 @@ -93,6 +93,7 @@ } } +gdb_test "info threads" ".*manythreads.*" "check thread original name" gdb_test_no_output "thread name zardoz" "give a name to the thread" gdb_test "info threads" ".*zardoz.*" "check thread name" Thanks, Will Huang