diff options
Diffstat (limited to 'sys/kern/kern_pmc.c')
| -rw-r--r-- | sys/kern/kern_pmc.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/sys/kern/kern_pmc.c b/sys/kern/kern_pmc.c index 8d9c7c0..2b50be0 100644 --- a/sys/kern/kern_pmc.c +++ b/sys/kern/kern_pmc.c @@ -34,10 +34,17 @@ __FBSDID("$FreeBSD$"); #include "opt_hwpmc_hooks.h" #include <sys/types.h> +#include <sys/ctype.h> +#include <sys/param.h> +#include <sys/malloc.h> +#include <sys/kernel.h> +#include <sys/lock.h> +#include <sys/mutex.h> #include <sys/pmc.h> #include <sys/pmckern.h> #include <sys/smp.h> #include <sys/sysctl.h> +#include <sys/systm.h> #ifdef HWPMC_HOOKS FEATURE(hwpmc_hooks, "Kernel support for HW PMC"); @@ -46,6 +53,9 @@ FEATURE(hwpmc_hooks, "Kernel support for HW PMC"); #define PMC_KERNEL_VERSION 0 #endif +MALLOC_DECLARE(M_PMCHOOKS); +MALLOC_DEFINE(M_PMCHOOKS, "pmchooks", "Memory space for PMC hooks"); + const int pmc_kernel_version = PMC_KERNEL_VERSION; /* Hook variable. */ @@ -74,6 +84,28 @@ volatile int pmc_ss_count; */ struct sx pmc_sx; +/* + * PMC Soft per cpu trapframe. + */ +struct trapframe pmc_tf[MAXCPU]; + +/* + * PMC Soft use a global table to store registered events. + */ + +SYSCTL_NODE(_kern, OID_AUTO, hwpmc, CTLFLAG_RW, 0, "HWPMC parameters"); + +static int pmc_softevents = 16; +TUNABLE_INT(PMC_SYSCTL_NAME_PREFIX "softevents", &pmc_softevents); +SYSCTL_INT(_kern_hwpmc, OID_AUTO, softevents, CTLFLAG_TUN|CTLFLAG_RD, + &pmc_softevents, 0, "maximum number of soft events"); + +struct mtx pmc_softs_mtx; +int pmc_softs_count; +struct pmc_soft **pmc_softs; + +MTX_SYSINIT(pmc_soft_mtx, &pmc_softs_mtx, "pmc-softs", MTX_SPIN); + static void pmc_init_sx(void) { @@ -182,3 +214,132 @@ pmc_cpu_max_active(void) } #endif + +/* + * Cleanup event name: + * - remove duplicate '_' + * - all uppercase + */ +static void +pmc_soft_namecleanup(char *name) +{ + char *p, *q; + + p = q = name; + + for ( ; *p == '_' ; p++) + ; + for ( ; *p ; p++) { + if (*p == '_' && (*(p + 1) == '_' || *(p + 1) == '\0')) + continue; + else + *q++ = toupper(*p); + } + *q = '\0'; +} + +void +pmc_soft_ev_register(struct pmc_soft *ps) +{ + static int warned = 0; + int n; + + ps->ps_running = 0; + ps->ps_ev.pm_ev_code = 0; /* invalid */ + pmc_soft_namecleanup(ps->ps_ev.pm_ev_name); + + mtx_lock_spin(&pmc_softs_mtx); + + if (pmc_softs_count >= pmc_softevents) { + /* + * XXX Reusing events can enter a race condition where + * new allocated event will be used as an old one. + */ + for (n = 0; n < pmc_softevents; n++) + if (pmc_softs[n] == NULL) + break; + if (n == pmc_softevents) { + mtx_unlock_spin(&pmc_softs_mtx); + if (!warned) { + printf("hwpmc: too many soft events, " + "increase kern.hwpmc.softevents tunable\n"); + warned = 1; + } + return; + } + + ps->ps_ev.pm_ev_code = PMC_EV_SOFT_FIRST + n; + pmc_softs[n] = ps; + } else { + ps->ps_ev.pm_ev_code = PMC_EV_SOFT_FIRST + pmc_softs_count; + pmc_softs[pmc_softs_count++] = ps; + } + + mtx_unlock_spin(&pmc_softs_mtx); +} + +void +pmc_soft_ev_deregister(struct pmc_soft *ps) +{ + + KASSERT(ps != NULL, ("pmc_soft_deregister: called with NULL")); + + mtx_lock_spin(&pmc_softs_mtx); + + if (ps->ps_ev.pm_ev_code != 0 && + (ps->ps_ev.pm_ev_code - PMC_EV_SOFT_FIRST) < pmc_softevents) { + KASSERT(ps->ps_ev.pm_ev_code >= PMC_EV_SOFT_FIRST && + ps->ps_ev.pm_ev_code <= PMC_EV_SOFT_LAST, + ("pmc_soft_deregister: invalid event value")); + pmc_softs[ps->ps_ev.pm_ev_code - PMC_EV_SOFT_FIRST] = NULL; + } + + mtx_unlock_spin(&pmc_softs_mtx); +} + +struct pmc_soft * +pmc_soft_ev_acquire(enum pmc_event ev) +{ + struct pmc_soft *ps; + + if (ev == 0 || (ev - PMC_EV_SOFT_FIRST) >= pmc_softevents) + return NULL; + + KASSERT(ev >= PMC_EV_SOFT_FIRST && + ev <= PMC_EV_SOFT_LAST, + ("event out of range")); + + mtx_lock_spin(&pmc_softs_mtx); + + ps = pmc_softs[ev - PMC_EV_SOFT_FIRST]; + if (ps == NULL) + mtx_unlock_spin(&pmc_softs_mtx); + + return ps; +} + +void +pmc_soft_ev_release(struct pmc_soft *ps) +{ + + mtx_unlock_spin(&pmc_softs_mtx); +} + +/* + * Initialise hwpmc. + */ +static void +init_hwpmc(void *dummy __unused) +{ + if (pmc_softevents <= 0 || + pmc_softevents > PMC_EV_DYN_COUNT) { + (void) printf("hwpmc: tunable \"softevents\"=%d out of " + "range.\n", pmc_softevents); + pmc_softevents = PMC_EV_DYN_COUNT; + } + pmc_softs = malloc(pmc_softevents * sizeof(struct pmc_soft *), M_PMCHOOKS, M_NOWAIT|M_ZERO); + KASSERT(pmc_softs != NULL, ("cannot allocate soft events table")); +} + +SYSINIT(hwpmc, SI_SUB_KDTRACE, SI_ORDER_FIRST, init_hwpmc, NULL); + |
