xref: /netbsd-src/external/gpl3/binutils/dist/gprofng/libcollector/profile.c (revision 0a3071956a3a9fdebdbf7f338cf2d439b45fc728)
1 /* Copyright (C) 2021 Free Software Foundation, Inc.
2    Contributed by Oracle.
3 
4    This file is part of GNU Binutils.
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 3, or (at your option)
9    any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program; if not, write to the Free Software
18    Foundation, 51 Franklin Street - Fifth Floor, Boston,
19    MA 02110-1301, USA.  */
20 
21 /*
22  *	Profile handling
23  *
24  *      Note: SIGPROF signal-handling and interval timer (once exclusive to
25  *      profile handling) are now common services provided by the dispatcher.
26  */
27 
28 #include "config.h"
29 #include <dlfcn.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <ucontext.h>
33 #include <unistd.h>
34 
35 #include "gp-defs.h"
36 #include "collector_module.h"
37 #include "gp-experiment.h"
38 #include "data_pckts.h"
39 #include "libcol_util.h"
40 #include "hwprofile.h"
41 #include "tsd.h"
42 
43 /* TprintfT(<level>,...) definitions.  Adjust per module as needed */
44 #define DBG_LT0 0 // for high-level configuration, unexpected errors/warnings
45 #define DBG_LT1 1 // for configuration details, warnings
46 #define DBG_LT2 2
47 #define DBG_LT3 3
48 
49 static int init_interface (CollectorInterface*);
50 static int open_experiment (const char *);
51 static int start_data_collection (void);
52 static int stop_data_collection (void);
53 static int close_experiment (void);
54 static int detach_experiment (void);
55 
56 static ModuleInterface module_interface ={
57   SP_PROFILE_FILE,          /* description */
58   init_interface,           /* initInterface */
59   open_experiment,          /* openExperiment */
60   start_data_collection,    /* startDataCollection */
61   stop_data_collection,     /* stopDataCollection */
62   close_experiment,         /* closeExperiment */
63   detach_experiment         /* detachExperiment (fork child) */
64 };
65 
66 static CollectorInterface *collector_interface = NULL;
67 static int prof_mode = 0;
68 static CollectorModule prof_hndl = COLLECTOR_MODULE_ERR;
69 static unsigned prof_key = COLLECTOR_TSD_INVALID_KEY;
70 
71 typedef struct ClockPacket
72 { /* clock profiling packet */
73   CM_Packet comm;
74   pthread_t lwp_id;
75   pthread_t thr_id;
76   uint32_t  cpu_id;
77   hrtime_t  tstamp __attribute__ ((packed));
78   uint64_t  frinfo __attribute__ ((packed));
79   int       mstate;     /* kernel microstate */
80   int       nticks;     /* number of ticks in that state */
81 } ClockPacket;
82 
83 /* XXX should be able to use local types */
84 #define CLOCK_TYPE OPROF_PCKT
85 
86 #define CHCK_REENTRANCE(x)  ( !prof_mode || ((x) = collector_interface->getKey( prof_key )) == NULL || (*(x) != 0) )
87 #define PUSH_REENTRANCE(x)  ((*(x))++)
88 #define POP_REENTRANCE(x)   ((*(x))--)
89 
90 #ifdef DEBUG
91 #define Tprintf(...)    if (collector_interface) collector_interface->writeDebugInfo( 0, __VA_ARGS__ )
92 #define TprintfT(...)   if (collector_interface) collector_interface->writeDebugInfo( 1, __VA_ARGS__ )
93 #else
94 #define Tprintf(...)
95 #define TprintfT(...)
96 #endif
97 
98 static void init_module () __attribute__ ((constructor));
99 
100 static void
101 init_module ()
102 {
103   __collector_dlsym_guard = 1;
104   RegModuleFunc reg_module = (RegModuleFunc) dlsym (RTLD_DEFAULT, "__collector_register_module");
105   __collector_dlsym_guard = 0;
106   if (reg_module == NULL)
107     {
108       TprintfT (0, "clockprof: init_module FAILED -- reg_module = NULL\n");
109       return;
110     }
111   prof_hndl = reg_module (&module_interface);
112   if (prof_hndl == COLLECTOR_MODULE_ERR && collector_interface != NULL)
113     {
114       Tprintf (0, "clockprof: ERROR: handle not created.\n");
115       collector_interface->writeLog ("<event kind=\"%s\" id=\"%d\">data handle not created</event>\n", SP_JCMD_CERROR, COL_ERROR_PROFINIT);
116     }
117   TprintfT (0, "clockprof: init_module, prof_hndl = %d\n", prof_hndl);
118   return;
119 }
120 
121 static int
122 init_interface (CollectorInterface *_collector_interface)
123 {
124   collector_interface = _collector_interface;
125   return COL_ERROR_NONE;
126 }
127 
128 static int
129 open_experiment (const char *exp)
130 {
131   if (collector_interface == NULL)
132     {
133       Tprintf (0, "clockprof: ERROR: collector_interface is null.\n");
134       return COL_ERROR_PROFINIT;
135     }
136   const char *params = collector_interface->getParams ();
137   while (params)
138     {
139       if (__collector_strStartWith (params, "p:") == 0)
140 	{
141 	  params += 2;
142 	  break;
143 	}
144       while (*params != 0 && *params != ';')
145 	params++;
146       if (*params == 0)
147 	params = NULL;
148       else
149 	params++;
150     }
151   if (params == NULL)   /* Clock profiling not specified */
152     return COL_ERROR_PROFINIT;
153   TprintfT (0, "clockprof: open_experiment %s -- %s\n", exp, params);
154   int prof_interval = CALL_UTIL (strtol)(params, NULL, 0);
155   prof_key = collector_interface->createKey (sizeof ( int), NULL, NULL);
156   if (prof_key == (unsigned) - 1)
157     {
158       Tprintf (0, "clockprof: ERROR: TSD key create failed.\n");
159       collector_interface->writeLog ("<event kind=\"%s\" id=\"%d\">TSD key not created</event>\n", SP_JCMD_CERROR, COL_ERROR_PROFINIT);
160       return COL_ERROR_PROFINIT;
161     }
162 
163   /* set dispatcher interval timer period used for all timed activities */
164   int prof_interval_actual = __collector_ext_itimer_set (prof_interval);
165   TprintfT (0, "clockprof: open_experiment(): __collector_ext_itimer_set (actual period=%d, req_period=%d)\n",
166 	    prof_interval_actual, prof_interval);
167   if (prof_interval_actual <= 0)
168     {
169       collector_interface->writeLog ("<event kind=\"%s\" id=\"%d\">itimer could not be set</event>\n", SP_JCMD_CERROR, COL_ERROR_PROFINIT);
170       return COL_ERROR_PROFINIT;
171     }
172   if ((prof_interval_actual >= (prof_interval + prof_interval / 10)) ||
173       (prof_interval_actual <= (prof_interval - prof_interval / 10)))
174     collector_interface->writeLog ("<event kind=\"%s\" id=\"%d\">%d -> %d</event>\n", SP_JCMD_CWARN, COL_WARN_PROFRND, prof_interval, prof_interval_actual);
175   else if (prof_interval_actual != prof_interval)
176     collector_interface->writeLog ("<event kind=\"%s\" id=\"%d\">%d -> %d</event>\n", SP_JCMD_COMMENT, COL_WARN_PROFRND, prof_interval, prof_interval_actual);
177   prof_interval = prof_interval_actual;
178   collector_interface->writeLog ("<profile name=\"%s\" ptimer=\"%d\" numstates=\"%d\">\n",
179 				 SP_JCMD_PROFILE, prof_interval, LMS_MAGIC_ID_LINUX);
180   collector_interface->writeLog ("  <profdata fname=\"%s\"/>\n",
181 				 module_interface.description);
182 
183   /* Record Profile packet description */
184   ClockPacket *cp = NULL;
185   collector_interface->writeLog ("  <profpckt kind=\"%d\" uname=\"" STXT ("Clock profiling data") "\">\n", CLOCK_TYPE);
186   collector_interface->writeLog ("    <field name=\"LWPID\" uname=\"" STXT ("Lightweight process id") "\" offset=\"%d\" type=\"%s\"/>\n",
187 				 &cp->lwp_id, sizeof (cp->lwp_id) == 4 ? "INT32" : "INT64");
188   collector_interface->writeLog ("    <field name=\"THRID\" uname=\"" STXT ("Thread number") "\" offset=\"%d\" type=\"%s\"/>\n",
189 				 &cp->thr_id, sizeof (cp->thr_id) == 4 ? "INT32" : "INT64");
190   collector_interface->writeLog ("    <field name=\"CPUID\" uname=\"" STXT ("CPU id") "\" offset=\"%d\" type=\"%s\"/>\n",
191 				 &cp->cpu_id, sizeof (cp->cpu_id) == 4 ? "INT32" : "INT64");
192   collector_interface->writeLog ("    <field name=\"TSTAMP\" uname=\"" STXT ("High resolution timestamp") "\" offset=\"%d\" type=\"%s\"/>\n",
193 				 &cp->tstamp, sizeof (cp->tstamp) == 4 ? "INT32" : "INT64");
194   collector_interface->writeLog ("    <field name=\"FRINFO\" offset=\"%d\" type=\"%s\"/>\n",
195 				 &cp->frinfo, sizeof (cp->frinfo) == 4 ? "INT32" : "INT64");
196   collector_interface->writeLog ("    <field name=\"MSTATE\" uname=\"" STXT ("Thread state") "\" offset=\"%d\" type=\"%s\"/>\n",
197 				 &cp->mstate, sizeof (cp->mstate) == 4 ? "INT32" : "INT64");
198   collector_interface->writeLog ("    <field name=\"NTICK\" uname=\"" STXT ("Duration") "\" offset=\"%d\" type=\"%s\"/>\n",
199 				 &cp->nticks, sizeof (cp->nticks) == 4 ? "INT32" : "INT64");
200   collector_interface->writeLog ("  </profpckt>\n");
201   collector_interface->writeLog ("</profile>\n");
202   return COL_ERROR_NONE;
203 }
204 
205 static int
206 start_data_collection (void)
207 {
208   TprintfT (0, "clockprof: start_data_collection\n");
209   prof_mode = 1;
210   return 0;
211 }
212 
213 static int
214 stop_data_collection (void)
215 {
216   prof_mode = 0;
217   TprintfT (0, "clockprof: stop_data_collection\n");
218   return 0;
219 }
220 
221 static int
222 close_experiment (void)
223 {
224   prof_mode = 0;
225   prof_key = COLLECTOR_TSD_INVALID_KEY;
226   TprintfT (0, "clockprof: close_experiment\n");
227   return 0;
228 }
229 
230 /* fork child.  Clean up state but don't write to experiment */
231 static int
232 detach_experiment (void)
233 {
234   prof_mode = 0;
235   prof_key = COLLECTOR_TSD_INVALID_KEY;
236   TprintfT (0, "clockprof: detach_experiment\n");
237   return 0;
238 }
239 
240 /*
241  * void collector_lost_profile_context
242  *      Placeholder/marker function used when profiling given NULL context.
243  */
244 void
245 __collector_lost_profile_context (void) { }
246 
247 /*
248  * void __collector_ext_profile_handler( siginfo_t *info, ucontext_t *context )
249  *      Handle real profile events to collect profile data.
250  */
251 void
252 __collector_ext_profile_handler (siginfo_t *info, ucontext_t *context)
253 {
254   int *guard;
255   if (!prof_mode) /* sigprof timer running only because hwprofile.c needs it */
256     return;
257   if (CHCK_REENTRANCE (guard))
258     {
259       TprintfT (0, "__collector_ext_profile_handler: ERROR: prof_mode=%d guard=%d!\n",
260 		prof_mode, guard ? *guard : -2);
261       return;
262     }
263   PUSH_REENTRANCE (guard);
264   TprintfT (DBG_LT3, "__collector_ext_profile_handler\n");
265   ucontext_t uctxmem;
266   if (context == NULL)
267     {
268       /* assume this case is rare, and accept overhead of creating dummy_uc */
269       TprintfT (0, "collector_profile_handler: ERROR: got NULL context!\n");
270       context = &uctxmem;
271       getcontext (context);     /* initialize dummy context */
272       SETFUNCTIONCONTEXT (context, &__collector_lost_profile_context);
273     }
274   ClockPacket pckt;
275   CALL_UTIL (memset)(&pckt, 0, sizeof ( pckt));
276   pckt.comm.tsize = sizeof ( pckt);
277   pckt.comm.type = CLOCK_TYPE;
278   pckt.lwp_id = __collector_lwp_self ();
279   pckt.thr_id = __collector_thr_self ();
280   pckt.cpu_id = CALL_UTIL (getcpuid)();
281   pckt.tstamp = collector_interface->getHiResTime ();
282   pckt.frinfo = collector_interface->getFrameInfo (COLLECTOR_MODULE_ERR, pckt.tstamp, FRINFO_FROM_UC, context);
283   pckt.mstate = LMS_LINUX_CPU;
284   pckt.nticks = 1;
285   collector_interface->writeDataPacket (prof_hndl, (CM_Packet*) & pckt);
286   POP_REENTRANCE (guard);
287 }
288