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-rw-r--r--arch/ia64/kernel/perfmon.c218
1 files changed, 193 insertions, 25 deletions
diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c
index 376fcbc3f8da..6407bff6bfd7 100644
--- a/arch/ia64/kernel/perfmon.c
+++ b/arch/ia64/kernel/perfmon.c
@@ -11,7 +11,7 @@
* 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>
*
@@ -497,6 +497,9 @@ typedef struct {
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,};
@@ -606,6 +609,7 @@ DEFINE_PER_CPU(unsigned long, pfm_syst_info);
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 */
@@ -1265,6 +1269,8 @@ out:
}
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)
{
@@ -1311,6 +1317,11 @@ 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;
@@ -1318,7 +1329,7 @@ pfm_reserve_session(struct task_struct *task, int is_syswide, unsigned int cpu)
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);
@@ -1366,6 +1377,12 @@ pfm_unreserve_session(pfm_context_t *ctx, int is_syswide, unsigned int cpu)
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;
@@ -4202,7 +4219,7 @@ pfm_context_load(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs)
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));
@@ -4704,16 +4721,26 @@ recheck:
if (task == current || ctx->ctx_fl_system) return 0;
/*
- * if context is UNLOADED we are safe to go
+ * we are monitoring another thread
*/
- if (state == PFM_CTX_UNLOADED) return 0;
-
- /*
- * no command can operate on a zombie context
- */
- 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;
}
/*
@@ -5532,26 +5559,32 @@ pfm_interrupt_handler(int irq, void *arg, struct pt_regs *regs)
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;
}
@@ -6402,6 +6435,141 @@ static struct irqaction perfmon_irqaction = {
.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
*/
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.