diff options
Diffstat (limited to 'arch/ia64/kernel/perfmon.c')
| -rw-r--r-- | arch/ia64/kernel/perfmon.c | 59 |
1 files changed, 28 insertions, 31 deletions
diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c index 71147be3279c..376fcbc3f8da 100644 --- a/arch/ia64/kernel/perfmon.c +++ b/arch/ia64/kernel/perfmon.c @@ -480,14 +480,6 @@ typedef struct { #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 */ unsigned long pfm_ovfl_intr_count; /* keep track of ovfl interrupts */ @@ -514,8 +506,8 @@ static LIST_HEAD(pfm_buffer_fmt_list); 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,}, @@ -1576,7 +1568,7 @@ pfm_read(struct file *filp, char __user *buf, size_t size, loff_t *ppos) 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); @@ -3695,8 +3687,6 @@ pfm_debug(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) 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) { @@ -4996,13 +4986,21 @@ pfm_context_force_terminate(pfm_context_t *ctx, struct pt_regs *regs) } 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; @@ -5039,18 +5037,15 @@ pfm_handle_work(void) //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")); @@ -5064,12 +5059,12 @@ pfm_handle_work(void) 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 @@ -5095,7 +5090,9 @@ skip_blocking: ctx->ctx_ovfl_regs[0] = 0UL; nothing_to_do: - + /* + * restore flags as they were upon entry + */ UNPROTECT_CTX(ctx, flags); } |
