diff options
Diffstat (limited to 'uts/common/dtrace/profile.c')
-rw-r--r-- | uts/common/dtrace/profile.c | 576 |
1 files changed, 576 insertions, 0 deletions
diff --git a/uts/common/dtrace/profile.c b/uts/common/dtrace/profile.c new file mode 100644 index 000000000000..8de919a851a2 --- /dev/null +++ b/uts/common/dtrace/profile.c @@ -0,0 +1,576 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2007 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#pragma ident "%Z%%M% %I% %E% SMI" + +#include <sys/errno.h> +#include <sys/stat.h> +#include <sys/modctl.h> +#include <sys/conf.h> +#include <sys/systm.h> +#include <sys/ddi.h> +#include <sys/sunddi.h> +#include <sys/cpuvar.h> +#include <sys/kmem.h> +#include <sys/strsubr.h> +#include <sys/dtrace.h> +#include <sys/cyclic.h> +#include <sys/atomic.h> + +static dev_info_t *profile_devi; +static dtrace_provider_id_t profile_id; + +/* + * Regardless of platform, the stack frames look like this in the case of the + * profile provider: + * + * profile_fire + * cyclic_expire + * cyclic_fire + * [ cbe ] + * [ interrupt code ] + * + * On x86, there are five frames from the generic interrupt code; further, the + * interrupted instruction appears as its own stack frame, giving us a total of + * 10. + * + * On SPARC, the picture is further complicated because the compiler + * optimizes away tail-calls -- so the following frames are optimized away: + * + * profile_fire + * cyclic_expire + * + * This gives three frames. However, on DEBUG kernels, the cyclic_expire + * frame cannot be tail-call eliminated, yielding four frames in this case. + * + * All of the above constraints lead to the mess below. Yes, the profile + * provider should ideally figure this out on-the-fly by hitting one of its own + * probes and then walking its own stack trace. This is complicated, however, + * and the static definition doesn't seem to be overly brittle. Still, we + * allow for a manual override in case we get it completely wrong. + */ +#ifdef __x86 +#define PROF_ARTIFICIAL_FRAMES 10 +#else +#ifdef __sparc +#ifdef DEBUG +#define PROF_ARTIFICIAL_FRAMES 4 +#else +#define PROF_ARTIFICIAL_FRAMES 3 +#endif +#endif +#endif + +#define PROF_NAMELEN 15 + +#define PROF_PROFILE 0 +#define PROF_TICK 1 +#define PROF_PREFIX_PROFILE "profile-" +#define PROF_PREFIX_TICK "tick-" + +typedef struct profile_probe { + char prof_name[PROF_NAMELEN]; + dtrace_id_t prof_id; + int prof_kind; + hrtime_t prof_interval; + cyclic_id_t prof_cyclic; +} profile_probe_t; + +typedef struct profile_probe_percpu { + hrtime_t profc_expected; + hrtime_t profc_interval; + profile_probe_t *profc_probe; +} profile_probe_percpu_t; + +hrtime_t profile_interval_min = NANOSEC / 5000; /* 5000 hz */ +int profile_aframes = 0; /* override */ + +static int profile_rates[] = { + 97, 199, 499, 997, 1999, + 4001, 4999, 0, 0, 0, + 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0 +}; + +static int profile_ticks[] = { + 1, 10, 100, 500, 1000, + 5000, 0, 0, 0, 0, + 0, 0, 0, 0, 0 +}; + +/* + * profile_max defines the upper bound on the number of profile probes that + * can exist (this is to prevent malicious or clumsy users from exhausing + * system resources by creating a slew of profile probes). At mod load time, + * this gets its value from PROFILE_MAX_DEFAULT or profile-max-probes if it's + * present in the profile.conf file. + */ +#define PROFILE_MAX_DEFAULT 1000 /* default max. number of probes */ +static uint32_t profile_max; /* maximum number of profile probes */ +static uint32_t profile_total; /* current number of profile probes */ + +static void +profile_fire(void *arg) +{ + profile_probe_percpu_t *pcpu = arg; + profile_probe_t *prof = pcpu->profc_probe; + hrtime_t late; + + late = dtrace_gethrtime() - pcpu->profc_expected; + pcpu->profc_expected += pcpu->profc_interval; + + dtrace_probe(prof->prof_id, CPU->cpu_profile_pc, + CPU->cpu_profile_upc, late, 0, 0); +} + +static void +profile_tick(void *arg) +{ + profile_probe_t *prof = arg; + + dtrace_probe(prof->prof_id, CPU->cpu_profile_pc, + CPU->cpu_profile_upc, 0, 0, 0); +} + +static void +profile_create(hrtime_t interval, const char *name, int kind) +{ + profile_probe_t *prof; + int nr_frames = PROF_ARTIFICIAL_FRAMES + dtrace_mach_aframes(); + + if (profile_aframes) + nr_frames = profile_aframes; + + if (interval < profile_interval_min) + return; + + if (dtrace_probe_lookup(profile_id, NULL, NULL, name) != 0) + return; + + atomic_add_32(&profile_total, 1); + if (profile_total > profile_max) { + atomic_add_32(&profile_total, -1); + return; + } + + prof = kmem_zalloc(sizeof (profile_probe_t), KM_SLEEP); + (void) strcpy(prof->prof_name, name); + prof->prof_interval = interval; + prof->prof_cyclic = CYCLIC_NONE; + prof->prof_kind = kind; + prof->prof_id = dtrace_probe_create(profile_id, + NULL, NULL, name, nr_frames, prof); +} + +/*ARGSUSED*/ +static void +profile_provide(void *arg, const dtrace_probedesc_t *desc) +{ + int i, j, rate, kind; + hrtime_t val = 0, mult = 1, len; + const char *name, *suffix = NULL; + + const struct { + char *prefix; + int kind; + } types[] = { + { PROF_PREFIX_PROFILE, PROF_PROFILE }, + { PROF_PREFIX_TICK, PROF_TICK }, + { NULL, NULL } + }; + + const struct { + char *name; + hrtime_t mult; + } suffixes[] = { + { "ns", NANOSEC / NANOSEC }, + { "nsec", NANOSEC / NANOSEC }, + { "us", NANOSEC / MICROSEC }, + { "usec", NANOSEC / MICROSEC }, + { "ms", NANOSEC / MILLISEC }, + { "msec", NANOSEC / MILLISEC }, + { "s", NANOSEC / SEC }, + { "sec", NANOSEC / SEC }, + { "m", NANOSEC * (hrtime_t)60 }, + { "min", NANOSEC * (hrtime_t)60 }, + { "h", NANOSEC * (hrtime_t)(60 * 60) }, + { "hour", NANOSEC * (hrtime_t)(60 * 60) }, + { "d", NANOSEC * (hrtime_t)(24 * 60 * 60) }, + { "day", NANOSEC * (hrtime_t)(24 * 60 * 60) }, + { "hz", 0 }, + { NULL } + }; + + if (desc == NULL) { + char n[PROF_NAMELEN]; + + /* + * If no description was provided, provide all of our probes. + */ + for (i = 0; i < sizeof (profile_rates) / sizeof (int); i++) { + if ((rate = profile_rates[i]) == 0) + continue; + + (void) snprintf(n, PROF_NAMELEN, "%s%d", + PROF_PREFIX_PROFILE, rate); + profile_create(NANOSEC / rate, n, PROF_PROFILE); + } + + for (i = 0; i < sizeof (profile_ticks) / sizeof (int); i++) { + if ((rate = profile_ticks[i]) == 0) + continue; + + (void) snprintf(n, PROF_NAMELEN, "%s%d", + PROF_PREFIX_TICK, rate); + profile_create(NANOSEC / rate, n, PROF_TICK); + } + + return; + } + + name = desc->dtpd_name; + + for (i = 0; types[i].prefix != NULL; i++) { + len = strlen(types[i].prefix); + + if (strncmp(name, types[i].prefix, len) != 0) + continue; + break; + } + + if (types[i].prefix == NULL) + return; + + kind = types[i].kind; + j = strlen(name) - len; + + /* + * We need to start before any time suffix. + */ + for (j = strlen(name); j >= len; j--) { + if (name[j] >= '0' && name[j] <= '9') + break; + suffix = &name[j]; + } + + ASSERT(suffix != NULL); + + /* + * Now determine the numerical value present in the probe name. + */ + for (; j >= len; j--) { + if (name[j] < '0' || name[j] > '9') + return; + + val += (name[j] - '0') * mult; + mult *= (hrtime_t)10; + } + + if (val == 0) + return; + + /* + * Look-up the suffix to determine the multiplier. + */ + for (i = 0, mult = 0; suffixes[i].name != NULL; i++) { + if (strcasecmp(suffixes[i].name, suffix) == 0) { + mult = suffixes[i].mult; + break; + } + } + + if (suffixes[i].name == NULL && *suffix != '\0') + return; + + if (mult == 0) { + /* + * The default is frequency-per-second. + */ + val = NANOSEC / val; + } else { + val *= mult; + } + + profile_create(val, name, kind); +} + +/*ARGSUSED*/ +static void +profile_destroy(void *arg, dtrace_id_t id, void *parg) +{ + profile_probe_t *prof = parg; + + ASSERT(prof->prof_cyclic == CYCLIC_NONE); + kmem_free(prof, sizeof (profile_probe_t)); + + ASSERT(profile_total >= 1); + atomic_add_32(&profile_total, -1); +} + +/*ARGSUSED*/ +static void +profile_online(void *arg, cpu_t *cpu, cyc_handler_t *hdlr, cyc_time_t *when) +{ + profile_probe_t *prof = arg; + profile_probe_percpu_t *pcpu; + + pcpu = kmem_zalloc(sizeof (profile_probe_percpu_t), KM_SLEEP); + pcpu->profc_probe = prof; + + hdlr->cyh_func = profile_fire; + hdlr->cyh_arg = pcpu; + hdlr->cyh_level = CY_HIGH_LEVEL; + + when->cyt_interval = prof->prof_interval; + when->cyt_when = dtrace_gethrtime() + when->cyt_interval; + + pcpu->profc_expected = when->cyt_when; + pcpu->profc_interval = when->cyt_interval; +} + +/*ARGSUSED*/ +static void +profile_offline(void *arg, cpu_t *cpu, void *oarg) +{ + profile_probe_percpu_t *pcpu = oarg; + + ASSERT(pcpu->profc_probe == arg); + kmem_free(pcpu, sizeof (profile_probe_percpu_t)); +} + +/*ARGSUSED*/ +static void +profile_enable(void *arg, dtrace_id_t id, void *parg) +{ + profile_probe_t *prof = parg; + cyc_omni_handler_t omni; + cyc_handler_t hdlr; + cyc_time_t when; + + ASSERT(prof->prof_interval != 0); + ASSERT(MUTEX_HELD(&cpu_lock)); + + if (prof->prof_kind == PROF_TICK) { + hdlr.cyh_func = profile_tick; + hdlr.cyh_arg = prof; + hdlr.cyh_level = CY_HIGH_LEVEL; + + when.cyt_interval = prof->prof_interval; + when.cyt_when = dtrace_gethrtime() + when.cyt_interval; + } else { + ASSERT(prof->prof_kind == PROF_PROFILE); + omni.cyo_online = profile_online; + omni.cyo_offline = profile_offline; + omni.cyo_arg = prof; + } + + if (prof->prof_kind == PROF_TICK) { + prof->prof_cyclic = cyclic_add(&hdlr, &when); + } else { + prof->prof_cyclic = cyclic_add_omni(&omni); + } +} + +/*ARGSUSED*/ +static void +profile_disable(void *arg, dtrace_id_t id, void *parg) +{ + profile_probe_t *prof = parg; + + ASSERT(prof->prof_cyclic != CYCLIC_NONE); + ASSERT(MUTEX_HELD(&cpu_lock)); + + cyclic_remove(prof->prof_cyclic); + prof->prof_cyclic = CYCLIC_NONE; +} + +/*ARGSUSED*/ +static int +profile_usermode(void *arg, dtrace_id_t id, void *parg) +{ + return (CPU->cpu_profile_pc == 0); +} + +static dtrace_pattr_t profile_attr = { +{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, +{ DTRACE_STABILITY_UNSTABLE, DTRACE_STABILITY_UNSTABLE, DTRACE_CLASS_UNKNOWN }, +{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, +{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, +{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, +}; + +static dtrace_pops_t profile_pops = { + profile_provide, + NULL, + profile_enable, + profile_disable, + NULL, + NULL, + NULL, + NULL, + profile_usermode, + profile_destroy +}; + +static int +profile_attach(dev_info_t *devi, ddi_attach_cmd_t cmd) +{ + switch (cmd) { + case DDI_ATTACH: + break; + case DDI_RESUME: + return (DDI_SUCCESS); + default: + return (DDI_FAILURE); + } + + if (ddi_create_minor_node(devi, "profile", S_IFCHR, 0, + DDI_PSEUDO, NULL) == DDI_FAILURE || + dtrace_register("profile", &profile_attr, + DTRACE_PRIV_KERNEL | DTRACE_PRIV_USER, NULL, + &profile_pops, NULL, &profile_id) != 0) { + ddi_remove_minor_node(devi, NULL); + return (DDI_FAILURE); + } + + profile_max = ddi_getprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS, + "profile-max-probes", PROFILE_MAX_DEFAULT); + + ddi_report_dev(devi); + profile_devi = devi; + return (DDI_SUCCESS); +} + +static int +profile_detach(dev_info_t *devi, ddi_detach_cmd_t cmd) +{ + switch (cmd) { + case DDI_DETACH: + break; + case DDI_SUSPEND: + return (DDI_SUCCESS); + default: + return (DDI_FAILURE); + } + + if (dtrace_unregister(profile_id) != 0) + return (DDI_FAILURE); + + ddi_remove_minor_node(devi, NULL); + return (DDI_SUCCESS); +} + +/*ARGSUSED*/ +static int +profile_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result) +{ + int error; + + switch (infocmd) { + case DDI_INFO_DEVT2DEVINFO: + *result = (void *)profile_devi; + error = DDI_SUCCESS; + break; + case DDI_INFO_DEVT2INSTANCE: + *result = (void *)0; + error = DDI_SUCCESS; + break; + default: + error = DDI_FAILURE; + } + return (error); +} + +/*ARGSUSED*/ +static int +profile_open(dev_t *devp, int flag, int otyp, cred_t *cred_p) +{ + return (0); +} + +static struct cb_ops profile_cb_ops = { + profile_open, /* open */ + nodev, /* close */ + nulldev, /* strategy */ + nulldev, /* print */ + nodev, /* dump */ + nodev, /* read */ + nodev, /* write */ + nodev, /* ioctl */ + nodev, /* devmap */ + nodev, /* mmap */ + nodev, /* segmap */ + nochpoll, /* poll */ + ddi_prop_op, /* cb_prop_op */ + 0, /* streamtab */ + D_NEW | D_MP /* Driver compatibility flag */ +}; + +static struct dev_ops profile_ops = { + DEVO_REV, /* devo_rev, */ + 0, /* refcnt */ + profile_info, /* get_dev_info */ + nulldev, /* identify */ + nulldev, /* probe */ + profile_attach, /* attach */ + profile_detach, /* detach */ + nodev, /* reset */ + &profile_cb_ops, /* driver operations */ + NULL, /* bus operations */ + nodev /* dev power */ +}; + +/* + * Module linkage information for the kernel. + */ +static struct modldrv modldrv = { + &mod_driverops, /* module type (this is a pseudo driver) */ + "Profile Interrupt Tracing", /* name of module */ + &profile_ops, /* driver ops */ +}; + +static struct modlinkage modlinkage = { + MODREV_1, + (void *)&modldrv, + NULL +}; + +int +_init(void) +{ + return (mod_install(&modlinkage)); +} + +int +_info(struct modinfo *modinfop) +{ + return (mod_info(&modlinkage, modinfop)); +} + +int +_fini(void) +{ + return (mod_remove(&modlinkage)); +} |