From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 15556 invoked by alias); 19 Jul 2011 17:44:46 -0000 Received: (qmail 15547 invoked by uid 22791); 19 Jul 2011 17:44:44 -0000 X-SWARE-Spam-Status: No, hits=-1.8 required=5.0 tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,KAM_STOCKGEN,RP_MATCHES_RCVD,SPF_HELO_PASS X-Spam-Check-By: sourceware.org Received: from smtp-out.google.com (HELO smtp-out.google.com) (216.239.44.51) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 19 Jul 2011 17:44:29 +0000 Received: from kpbe11.cbf.corp.google.com (kpbe11.cbf.corp.google.com [172.25.105.75]) by smtp-out.google.com with ESMTP id p6JHiT0u018243 for ; Tue, 19 Jul 2011 10:44:29 -0700 Received: from elbrus2.mtv.corp.google.com (elbrus2.mtv.corp.google.com [172.18.111.111]) by kpbe11.cbf.corp.google.com with ESMTP id p6JHiSSb006153; Tue, 19 Jul 2011 10:44:28 -0700 Received: by elbrus2.mtv.corp.google.com (Postfix, from userid 74925) id D9BC3190BC8; Tue, 19 Jul 2011 10:44:27 -0700 (PDT) To: gdb-patches@sourceware.org CC: ppluzhnikov@google.com Subject: [RFC][patch] Allow user to disable tracepoint support in gdbserver via command line Message-Id: <20110719174427.D9BC3190BC8@elbrus2.mtv.corp.google.com> Date: Tue, 19 Jul 2011 18:13:00 -0000 From: ppluzhnikov@google.com (Paul Pluzhnikov) X-IsSubscribed: yes 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 X-SW-Source: 2011-07/txt/msg00484.txt.bz2 Greetings, Following up on my earlier "slow on high-latency links" message: http://sourceware.org/ml/gdb-patches/2011-07/msg00391.html ... Another source of major slowness for me is the gdbserver querying for tracepoint symbols. I see repeated (for each SOLIB) sequences of: 00:00:44 Sending packet: $qSymbol::#5b...Packet received: qSymbol:6764625f6167656e745f6764625f74705f686561705f627566666572 00:00:44 Packet qSymbol (symbol-lookup) is supported 00:00:44 Sending packet: $qSymbol::6764625f6167656e745f6764625f74705f686561705f627566666572#1e...Packet received: qSymbol:6764625f6167656e745f6764625f6a756d705f7061645f627566666572 00:00:44 Sending packet: $qSymbol::6764625f6167656e745f6764625f6a756d705f7061645f627566666572#e1...Packet received: qSymbol:6764625f6167656e745f6764625f6a756d705f7061645f6275666665725f656e64 00:00:44 Sending packet: $qSymbol::6764625f6167656e745f6764625f6a756d705f7061645f6275666665725f656e64#ec...Packet received: qSymbol:6764625f6167656e745f636f6c6c656374696e67 00:00:44 Sending packet: $qSymbol::6764625f6167656e745f636f6c6c656374696e67#02...Packet received: qSymbol:6764625f6167656e745f6764625f636f6c6c656374 00:00:45 Sending packet: $qSymbol::6764625f6167656e745f6764625f636f6c6c656374#65...Packet received: qSymbol:6764625f6167656e745f73746f705f74726163696e67 00:00:45 Sending packet: $qSymbol::6764625f6167656e745f73746f705f74726163696e67#a3...Packet received: qSymbol:6764625f6167656e745f666c7573685f74726163655f627566666572 00:00:45 Sending packet: $qSymbol::6764625f6167656e745f666c7573685f74726163655f627566666572#23...Packet received: qSymbol:6764625f6167656e745f61626f75745f746f5f726571756573745f6275666665725f7370616365 00:00:45 Sending packet: $qSymbol::6764625f6167656e745f61626f75745f746f5f726571756573745f6275666665725f7370616365#3e...Packet received: qSymbol:6764625f6167656e745f74726163655f6275666665725f69735f66756c6c 00:00:45 Sending packet: $qSymbol::6764625f6167656e745f74726163655f6275666665725f69735f66756c6c#58...Packet received: qSymbol:6764625f6167656e745f73746f7070696e675f7472616365706f696e74 00:00:45 Sending packet: $qSymbol::6764625f6167656e745f73746f7070696e675f7472616365706f696e74#ed...Packet received: qSymbol:6764625f6167656e745f657870725f6576616c5f726573756c74 00:00:46 Sending packet: $qSymbol::6764625f6167656e745f657870725f6576616c5f726573756c74#7b...Packet received: qSymbol:6764625f6167656e745f6572726f725f7472616365706f696e74 00:00:46 Sending packet: $qSymbol::6764625f6167656e745f6572726f725f7472616365706f696e74#79...Packet received: qSymbol:6764625f6167656e745f7472616365706f696e7473 00:00:46 Sending packet: $qSymbol::6764625f6167656e745f7472616365706f696e7473#06...Packet received: qSymbol:6764625f6167656e745f74726163696e67 00:00:46 Sending packet: $qSymbol::6764625f6167656e745f74726163696e67#30...Packet received: qSymbol:6764625f6167656e745f74726163655f6275666665725f6374726c 00:00:46 Sending packet: $qSymbol::6764625f6167656e745f74726163655f6275666665725f6374726c#b0...Packet received: qSymbol:6764625f6167656e745f74726163655f6275666665725f6374726c5f63757272 00:00:46 Sending packet: $qSymbol::6764625f6167656e745f74726163655f6275666665725f6374726c5f63757272#f2...Packet received: qSymbol:6764625f6167656e745f74726163655f6275666665725f6c6f 00:00:47 Sending packet: $qSymbol::6764625f6167656e745f74726163655f6275666665725f6c6f#0f...Packet received: qSymbol:6764625f6167656e745f74726163655f6275666665725f6869 00:00:47 Sending packet: $qSymbol::6764625f6167656e745f74726163655f6275666665725f6869#b7...Packet received: qSymbol:6764625f6167656e745f74726163656672616d655f726561645f636f756e74 00:00:47 Sending packet: $qSymbol::6764625f6167656e745f74726163656672616d655f726561645f636f756e74#b7...Packet received: qSymbol:6764625f6167656e745f74726163656672616d655f77726974655f636f756e74 00:00:47 Sending packet: $qSymbol::6764625f6167656e745f74726163656672616d655f77726974655f636f756e74#2e...Packet received: qSymbol:6764625f6167656e745f74726163656672616d65735f63726561746564 00:00:47 Sending packet: $qSymbol::6764625f6167656e745f74726163656672616d65735f63726561746564#4e...Packet received: qSymbol:6764625f6167656e745f74726163655f73746174655f7661726961626c6573 00:00:47 Sending packet: $qSymbol::6764625f6167656e745f74726163655f73746174655f7661726961626c6573#55...Packet received: qSymbol:6764625f6167656e745f6765745f7261775f726567 00:00:48 Sending packet: $qSymbol::6764625f6167656e745f6765745f7261775f726567#0d...Packet received: qSymbol:6764625f6167656e745f6765745f74726163655f73746174655f7661726961626c655f76616c7565 00:00:48 Sending packet: $qSymbol::6764625f6167656e745f6765745f74726163655f73746174655f7661726961626c655f76616c7565#a8...Packet received: qSymbol:6764625f6167656e745f7365745f74726163655f73746174655f7661726961626c655f76616c7565 00:00:48 Sending packet: $qSymbol::6764625f6167656e745f7365745f74726163655f73746174655f7661726961626c655f76616c7565#a5...Packet received: qSymbol:6764625f6167656e745f7573745f6c6f61646564 00:00:48 Sending packet: $qSymbol::6764625f6167656e745f7573745f6c6f61646564#cc...Packet received: qSymbol:6764625f6167656e745f68656c7065725f7468726561645f6964 00:00:48 Sending packet: $qSymbol::6764625f6167656e745f68656c7065725f7468726561645f6964#4f...Packet received: qSymbol:6764625f6167656e745f636d645f627566 00:00:48 Sending packet: $qSymbol::6764625f6167656e745f636d645f627566#5d...Packet received: qSymbol:6e70746c5f76657273696f6e 00:00:49 Sending packet: $qSymbol::6e70746c5f76657273696f6e#4d...Packet received: qSymbol:6e70746c5f76657273696f6e 00:00:49 Sending packet: $qSymbol::6e70746c5f76657273696f6e#4d...Packet received: qSymbol:6e70746c5f76657273696f6e 00:00:49 Sending packet: $qSymbol::6e70746c5f76657273696f6e#4d...Packet received: OK Since I have 10 shared libraries in that executable, this costs me about 1 minute delay, and is completely wasted, because I am not going to use tracepoints. Attached patch allows me to disable tracepoint support via --disable-tracepoints command line flag. The patch would need documentation update, which I'll provide if the idea of turning off tracepoints like that is not found too repulsive. Thanks, -- Paul Pluzhnikov 2011-07-19 Paul Pluzhnikov * server.c (disable_tracepoints): New variable. (support_tracepoints_p): New function. (handle_general_set, handle_query): Use it. (main): Handle --disable-tracepoints. Index: gdbserver/server.c =================================================================== RCS file: /cvs/src/src/gdb/gdbserver/server.c,v retrieving revision 1.145 diff -u -p -r1.145 server.c --- gdbserver/server.c 12 May 2011 12:09:17 -0000 1.145 +++ gdbserver/server.c 15 Jul 2011 22:54:42 -0000 @@ -92,6 +92,9 @@ int disable_packet_Tthread; int disable_packet_qC; int disable_packet_qfThreadInfo; +/* Set if you want to disable tracepoints. */ +int disable_tracepoints; + /* Last status reported to GDB. */ static struct target_waitstatus last_status; static ptid_t last_ptid; @@ -117,6 +120,14 @@ struct vstop_notif /* The pending stop replies list head. */ static struct vstop_notif *notif_queue = NULL; +/* Do we support tracepoints. */ + +static int +support_tracepoints_p () +{ + return !disable_tracepoints && target_supports_tracepoints (); +} + /* Put a stop reply to the stop reply queue. */ static void @@ -498,8 +509,7 @@ handle_general_set (char *own_buf) return; } - if (target_supports_tracepoints () - && handle_tracepoint_general_set (own_buf)) + if (support_tracepoints_p () && handle_tracepoint_general_set (own_buf)) return; /* Otherwise we didn't know what packet it was. Say we didn't @@ -1378,7 +1388,7 @@ handle_query (char *own_buf, int packet_ we access breakpoint shadows. */ validate_breakpoints (); - if (target_supports_tracepoints ()) + if (support_tracepoints_p ()) tracepoint_look_up_symbols (); if (target_running () && the_target->look_up_symbols != NULL) @@ -1529,7 +1539,7 @@ handle_query (char *own_buf, int packet_ strcat (own_buf, ";qXfer:threads:read+"); - if (target_supports_tracepoints ()) + if (support_tracepoints_p ()) { strcat (own_buf, ";ConditionalTracepoints+"); strcat (own_buf, ";TraceStateVariables+"); @@ -1730,7 +1740,7 @@ handle_query (char *own_buf, int packet_ if (handle_qxfer (own_buf, packet_len, new_packet_len_p)) return; - if (target_supports_tracepoints () && handle_tracepoint_query (own_buf)) + if (support_tracepoints_p () && handle_tracepoint_query (own_buf)) return; /* Otherwise we didn't know what packet it was. Say we didn't @@ -2533,6 +2543,8 @@ main (int argc, char *argv[]) } else if (strcmp (*next_arg, "--once") == 0) run_once = 1; + else if (strcmp (*next_arg, "--disable-tracepoints") == 0) + disable_tracepoints = 1; else { fprintf (stderr, "Unknown argument: %s\n", *next_arg); @@ -2585,7 +2597,7 @@ main (int argc, char *argv[]) initialize_inferiors (); initialize_async_io (); initialize_low (); - if (target_supports_tracepoints ()) + if (support_tracepoints_p ()) initialize_tracepoint (); own_buf = xmalloc (PBUFSIZ + 1);