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32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/sysproto.h>
35 #include <sys/kernel.h>
37 #include <sys/mutex.h>
39 #include <sys/resourcevar.h>
40 #include <sys/sysctl.h>
42 #include <machine/cpu.h>
45 * Profiling system call.
47 * The scale factor is a fixed point number with 16 bits of fraction, so that
48 * 1.0 is represented as 0x10000. A scale factor of 0 turns off profiling.
50 #ifndef _SYS_SYSPROTO_H_
60 sys_profil(struct thread *td, struct profil_args *uap)
65 if (uap->scale > (1 << 16))
69 if (uap->scale == 0) {
76 upp = &td->td_proc->p_stats->p_prof;
78 upp->pr_off = uap->offset;
79 upp->pr_scale = uap->scale;
80 upp->pr_base = uap->samples;
81 upp->pr_size = uap->size;
90 * Scale is a fixed-point number with the binary point 16 bits
91 * into the value, and is <= 1.0. pc is at most 32 bits, so the
92 * intermediate result is at most 48 bits.
94 #define PC_TO_INDEX(pc, prof) \
95 ((int)(((u_quad_t)((pc) - (prof)->pr_off) * \
96 (u_quad_t)((prof)->pr_scale)) >> 16) & ~1)
99 * Collect user-level profiling statistics; called on a profiling tick,
100 * when a process is running in user-mode. This routine may be called
101 * from an interrupt context. We perform the update with an AST
102 * that will vector us to trap() with a context in which copyin and
103 * copyout will work. Trap will then call addupc_task().
105 * Note that we may (rarely) not get around to the AST soon enough, and
106 * lose profile ticks when the next tick overwrites this one, but in this
107 * case the system is overloaded and the profile is probably already
111 addupc_intr(struct thread *td, uintfptr_t pc, u_int ticks)
117 prof = &td->td_proc->p_stats->p_prof;
118 PROC_PROFLOCK(td->td_proc);
119 if (pc < prof->pr_off || PC_TO_INDEX(pc, prof) >= prof->pr_size) {
120 PROC_PROFUNLOCK(td->td_proc);
121 return; /* out of range; ignore */
124 PROC_PROFUNLOCK(td->td_proc);
125 td->td_profil_addr = pc;
126 td->td_profil_ticks = ticks;
127 td->td_pflags |= TDP_OWEUPC;
128 ast_sched(td, TDA_OWEUPC);
132 * Actually update the profiling statistics. If the update fails, we
133 * simply turn off profiling.
136 addupc_task(struct thread *td, uintfptr_t pc, u_int ticks)
138 struct proc *p = td->td_proc;
149 if (!(p->p_flag & P_PROFIL)) {
154 prof = &p->p_stats->p_prof;
156 if (pc < prof->pr_off ||
157 (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size) {
162 addr = prof->pr_base + i;
165 if (copyin(addr, &v, sizeof(v)) == 0) {
167 if (copyout(&v, addr, sizeof(v)) == 0) {
176 if (--p->p_profthreads == 0) {
177 if (p->p_flag & P_STOPPROF) {
178 wakeup(&p->p_profthreads);
179 p->p_flag &= ~P_STOPPROF;