* Version Perfmon-2.x is a rewrite of perfmon-1.x
* by Stephane Eranian, Hewlett Packard Co.
*
- * Copyright (C) 1999-2003, 2005 Hewlett Packard Co
+ * Copyright (C) 1999-2005 Hewlett Packard Co
* Stephane Eranian <eranian@hpl.hp.com>
* David Mosberger-Tang <davidm@hpl.hp.com>
*
#define PFM_CMD_ARG_MANY -1 /* cannot be zero */
-typedef struct {
- int debug; /* turn on/off debugging via syslog */
- int debug_ovfl; /* turn on/off debug printk in overflow handler */
- int fastctxsw; /* turn on/off fast (unsecure) ctxsw */
- int expert_mode; /* turn on/off value checking */
- int debug_pfm_read;
-} pfm_sysctl_t;
-
typedef struct {
unsigned long pfm_spurious_ovfl_intr_count; /* keep track of spurious ovfl interrupts */
unsigned long pfm_replay_ovfl_intr_count; /* keep track of replayed ovfl interrupts */
static pfm_stats_t pfm_stats[NR_CPUS];
static pfm_session_t pfm_sessions; /* global sessions information */
+static spinlock_t pfm_alt_install_check = SPIN_LOCK_UNLOCKED;
+static pfm_intr_handler_desc_t *pfm_alt_intr_handler;
+
static struct proc_dir_entry *perfmon_dir;
static pfm_uuid_t pfm_null_uuid = {0,};
static pmu_config_t *pmu_conf;
/* sysctl() controls */
-static pfm_sysctl_t pfm_sysctl;
-int pfm_debug_var;
+pfm_sysctl_t pfm_sysctl;
+EXPORT_SYMBOL(pfm_sysctl);
static ctl_table pfm_ctl_table[]={
{1, "debug", &pfm_sysctl.debug, sizeof(int), 0666, NULL, &proc_dointvec, NULL,},
DEFINE_PER_CPU(struct task_struct *, pmu_owner);
DEFINE_PER_CPU(pfm_context_t *, pmu_ctx);
DEFINE_PER_CPU(unsigned long, pmu_activation_number);
+EXPORT_PER_CPU_SYMBOL_GPL(pfm_syst_info);
/* forward declaration */
}
EXPORT_SYMBOL(pfm_unregister_buffer_fmt);
+extern void update_pal_halt_status(int);
+
static int
pfm_reserve_session(struct task_struct *task, int is_syswide, unsigned int cpu)
{
is_syswide,
cpu));
+ /*
+ * disable default_idle() to go to PAL_HALT
+ */
+ update_pal_halt_status(0);
+
UNLOCK_PFS(flags);
return 0;
error_conflict:
DPRINT(("system wide not possible, conflicting session [%d] on CPU%d\n",
pfm_sessions.pfs_sys_session[cpu]->pid,
- smp_processor_id()));
+ cpu));
abort:
UNLOCK_PFS(flags);
is_syswide,
cpu));
+ /*
+ * if possible, enable default_idle() to go into PAL_HALT
+ */
+ if (pfm_sessions.pfs_task_sessions == 0 && pfm_sessions.pfs_sys_sessions == 0)
+ update_pal_halt_status(1);
+
UNLOCK_PFS(flags);
return 0;
goto abort_locked;
}
- DPRINT(("[%d] fd=%d type=%d\n", current->pid, msg->pfm_gen_msg.msg_ctx_fd, msg->pfm_gen_msg.msg_type));
+ DPRINT(("fd=%d type=%d\n", msg->pfm_gen_msg.msg_ctx_fd, msg->pfm_gen_msg.msg_type));
ret = -EFAULT;
if(copy_to_user(buf, msg, sizeof(pfm_msg_t)) == 0) ret = sizeof(pfm_msg_t);
pfm_sysctl.debug = m == 0 ? 0 : 1;
- pfm_debug_var = pfm_sysctl.debug;
-
printk(KERN_INFO "perfmon debugging %s (timing reset)\n", pfm_sysctl.debug ? "on" : "off");
if (m == 0) {
DPRINT(("cannot load to [%d], invalid ctx_state=%d\n",
req->load_pid,
ctx->ctx_state));
- return -EINVAL;
+ return -EBUSY;
}
DPRINT(("load_pid [%d] using_dbreg=%d\n", req->load_pid, ctx->ctx_fl_using_dbreg));
if (task == current || ctx->ctx_fl_system) return 0;
/*
- * if context is UNLOADED we are safe to go
- */
- if (state == PFM_CTX_UNLOADED) return 0;
-
- /*
- * no command can operate on a zombie context
+ * we are monitoring another thread
*/
- if (state == PFM_CTX_ZOMBIE) {
- DPRINT(("cmd %d state zombie cannot operate on context\n", cmd));
- return -EINVAL;
+ switch(state) {
+ case PFM_CTX_UNLOADED:
+ /*
+ * if context is UNLOADED we are safe to go
+ */
+ return 0;
+ case PFM_CTX_ZOMBIE:
+ /*
+ * no command can operate on a zombie context
+ */
+ DPRINT(("cmd %d state zombie cannot operate on context\n", cmd));
+ return -EINVAL;
+ case PFM_CTX_MASKED:
+ /*
+ * PMU state has been saved to software even though
+ * the thread may still be running.
+ */
+ if (cmd != PFM_UNLOAD_CONTEXT) return 0;
}
/*
}
static int pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds);
-
+ /*
+ * pfm_handle_work() can be called with interrupts enabled
+ * (TIF_NEED_RESCHED) or disabled. The down_interruptible
+ * call may sleep, therefore we must re-enable interrupts
+ * to avoid deadlocks. It is safe to do so because this function
+ * is called ONLY when returning to user level (PUStk=1), in which case
+ * there is no risk of kernel stack overflow due to deep
+ * interrupt nesting.
+ */
void
pfm_handle_work(void)
{
pfm_context_t *ctx;
struct pt_regs *regs;
- unsigned long flags;
+ unsigned long flags, dummy_flags;
unsigned long ovfl_regs;
unsigned int reason;
int ret;
//if (CTX_OVFL_NOBLOCK(ctx)) goto skip_blocking;
if (reason == PFM_TRAP_REASON_RESET) goto skip_blocking;
+ /*
+ * restore interrupt mask to what it was on entry.
+ * Could be enabled/diasbled.
+ */
UNPROTECT_CTX(ctx, flags);
- /*
- * pfm_handle_work() is currently called with interrupts disabled.
- * The down_interruptible call may sleep, therefore we
- * must re-enable interrupts to avoid deadlocks. It is
- * safe to do so because this function is called ONLY
- * when returning to user level (PUStk=1), in which case
- * there is no risk of kernel stack overflow due to deep
- * interrupt nesting.
- */
- BUG_ON(flags & IA64_PSR_I);
+ /*
+ * force interrupt enable because of down_interruptible()
+ */
local_irq_enable();
DPRINT(("before block sleeping\n"));
DPRINT(("after block sleeping ret=%d\n", ret));
/*
- * disable interrupts to restore state we had upon entering
- * this function
+ * lock context and mask interrupts again
+ * We save flags into a dummy because we may have
+ * altered interrupts mask compared to entry in this
+ * function.
*/
- local_irq_disable();
-
- PROTECT_CTX(ctx, flags);
+ PROTECT_CTX(ctx, dummy_flags);
/*
* we need to read the ovfl_regs only after wake-up
ctx->ctx_ovfl_regs[0] = 0UL;
nothing_to_do:
-
+ /*
+ * restore flags as they were upon entry
+ */
UNPROTECT_CTX(ctx, flags);
}
int ret;
this_cpu = get_cpu();
- min = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min;
- max = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max;
+ if (likely(!pfm_alt_intr_handler)) {
+ min = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min;
+ max = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max;
- start_cycles = ia64_get_itc();
+ start_cycles = ia64_get_itc();
- ret = pfm_do_interrupt_handler(irq, arg, regs);
+ ret = pfm_do_interrupt_handler(irq, arg, regs);
- total_cycles = ia64_get_itc();
+ total_cycles = ia64_get_itc();
- /*
- * don't measure spurious interrupts
- */
- if (likely(ret == 0)) {
- total_cycles -= start_cycles;
+ /*
+ * don't measure spurious interrupts
+ */
+ if (likely(ret == 0)) {
+ total_cycles -= start_cycles;
- if (total_cycles < min) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min = total_cycles;
- if (total_cycles > max) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max = total_cycles;
+ if (total_cycles < min) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min = total_cycles;
+ if (total_cycles > max) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max = total_cycles;
- pfm_stats[this_cpu].pfm_ovfl_intr_cycles += total_cycles;
+ pfm_stats[this_cpu].pfm_ovfl_intr_cycles += total_cycles;
+ }
+ }
+ else {
+ (*pfm_alt_intr_handler->handler)(irq, arg, regs);
}
+
put_cpu_no_resched();
return IRQ_HANDLED;
}
.name = "perfmon"
};
+static void
+pfm_alt_save_pmu_state(void *data)
+{
+ struct pt_regs *regs;
+
+ regs = ia64_task_regs(current);
+
+ DPRINT(("called\n"));
+
+ /*
+ * should not be necessary but
+ * let's take not risk
+ */
+ pfm_clear_psr_up();
+ pfm_clear_psr_pp();
+ ia64_psr(regs)->pp = 0;
+
+ /*
+ * This call is required
+ * May cause a spurious interrupt on some processors
+ */
+ pfm_freeze_pmu();
+
+ ia64_srlz_d();
+}
+
+void
+pfm_alt_restore_pmu_state(void *data)
+{
+ struct pt_regs *regs;
+
+ regs = ia64_task_regs(current);
+
+ DPRINT(("called\n"));
+
+ /*
+ * put PMU back in state expected
+ * by perfmon
+ */
+ pfm_clear_psr_up();
+ pfm_clear_psr_pp();
+ ia64_psr(regs)->pp = 0;
+
+ /*
+ * perfmon runs with PMU unfrozen at all times
+ */
+ pfm_unfreeze_pmu();
+
+ ia64_srlz_d();
+}
+
+int
+pfm_install_alt_pmu_interrupt(pfm_intr_handler_desc_t *hdl)
+{
+ int ret, i;
+ int reserve_cpu;
+
+ /* some sanity checks */
+ if (hdl == NULL || hdl->handler == NULL) return -EINVAL;
+
+ /* do the easy test first */
+ if (pfm_alt_intr_handler) return -EBUSY;
+
+ /* one at a time in the install or remove, just fail the others */
+ if (!spin_trylock(&pfm_alt_install_check)) {
+ return -EBUSY;
+ }
+
+ /* reserve our session */
+ for_each_online_cpu(reserve_cpu) {
+ ret = pfm_reserve_session(NULL, 1, reserve_cpu);
+ if (ret) goto cleanup_reserve;
+ }
+
+ /* save the current system wide pmu states */
+ ret = on_each_cpu(pfm_alt_save_pmu_state, NULL, 0, 1);
+ if (ret) {
+ DPRINT(("on_each_cpu() failed: %d\n", ret));
+ goto cleanup_reserve;
+ }
+
+ /* officially change to the alternate interrupt handler */
+ pfm_alt_intr_handler = hdl;
+
+ spin_unlock(&pfm_alt_install_check);
+
+ return 0;
+
+cleanup_reserve:
+ for_each_online_cpu(i) {
+ /* don't unreserve more than we reserved */
+ if (i >= reserve_cpu) break;
+
+ pfm_unreserve_session(NULL, 1, i);
+ }
+
+ spin_unlock(&pfm_alt_install_check);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pfm_install_alt_pmu_interrupt);
+
+int
+pfm_remove_alt_pmu_interrupt(pfm_intr_handler_desc_t *hdl)
+{
+ int i;
+ int ret;
+
+ if (hdl == NULL) return -EINVAL;
+
+ /* cannot remove someone else's handler! */
+ if (pfm_alt_intr_handler != hdl) return -EINVAL;
+
+ /* one at a time in the install or remove, just fail the others */
+ if (!spin_trylock(&pfm_alt_install_check)) {
+ return -EBUSY;
+ }
+
+ pfm_alt_intr_handler = NULL;
+
+ ret = on_each_cpu(pfm_alt_restore_pmu_state, NULL, 0, 1);
+ if (ret) {
+ DPRINT(("on_each_cpu() failed: %d\n", ret));
+ }
+
+ for_each_online_cpu(i) {
+ pfm_unreserve_session(NULL, 1, i);
+ }
+
+ spin_unlock(&pfm_alt_install_check);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pfm_remove_alt_pmu_interrupt);
+
/*
* perfmon initialization routine, called from the initcall() table
*/
git://git.onelab.eu / linux-2.6.git / blobdiff