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-rw-r--r--kernel/events/core.c85
-rw-r--r--kernel/events/internal.h6
-rw-r--r--kernel/events/ring_buffer.c31
3 files changed, 92 insertions, 30 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 03ac9c8b02fb..ce64f3fed5c6 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1249,26 +1249,31 @@ unclone_ctx(struct perf_event_context *ctx)
 	return parent_ctx;
 }
 
-static u32 perf_event_pid(struct perf_event *event, struct task_struct *p)
+static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p,
+				enum pid_type type)
 {
+	u32 nr;
 	/*
 	 * only top level events have the pid namespace they were created in
 	 */
 	if (event->parent)
 		event = event->parent;
 
-	return task_tgid_nr_ns(p, event->ns);
+	nr = __task_pid_nr_ns(p, type, event->ns);
+	/* avoid -1 if it is idle thread or runs in another ns */
+	if (!nr && !pid_alive(p))
+		nr = -1;
+	return nr;
 }
 
-static u32 perf_event_tid(struct perf_event *event, struct task_struct *p)
+static u32 perf_event_pid(struct perf_event *event, struct task_struct *p)
 {
-	/*
-	 * only top level events have the pid namespace they were created in
-	 */
-	if (event->parent)
-		event = event->parent;
+	return perf_event_pid_type(event, p, __PIDTYPE_TGID);
+}
 
-	return task_pid_nr_ns(p, event->ns);
+static u32 perf_event_tid(struct perf_event *event, struct task_struct *p)
+{
+	return perf_event_pid_type(event, p, PIDTYPE_PID);
 }
 
 /*
@@ -1570,6 +1575,9 @@ static void __perf_event_header_size(struct perf_event *event, u64 sample_type)
 	if (sample_type & PERF_SAMPLE_TRANSACTION)
 		size += sizeof(data->txn);
 
+	if (sample_type & PERF_SAMPLE_PHYS_ADDR)
+		size += sizeof(data->phys_addr);
+
 	event->header_size = size;
 }
 
@@ -3211,6 +3219,13 @@ static void perf_event_context_sched_in(struct perf_event_context *ctx,
 		return;
 
 	perf_ctx_lock(cpuctx, ctx);
+	/*
+	 * We must check ctx->nr_events while holding ctx->lock, such
+	 * that we serialize against perf_install_in_context().
+	 */
+	if (!ctx->nr_events)
+		goto unlock;
+
 	perf_pmu_disable(ctx->pmu);
 	/*
 	 * We want to keep the following priority order:
@@ -3224,6 +3239,8 @@ static void perf_event_context_sched_in(struct perf_event_context *ctx,
 		cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
 	perf_event_sched_in(cpuctx, ctx, task);
 	perf_pmu_enable(ctx->pmu);
+
+unlock:
 	perf_ctx_unlock(cpuctx, ctx);
 }
 
@@ -6003,6 +6020,9 @@ void perf_output_sample(struct perf_output_handle *handle,
 		}
 	}
 
+	if (sample_type & PERF_SAMPLE_PHYS_ADDR)
+		perf_output_put(handle, data->phys_addr);
+
 	if (!event->attr.watermark) {
 		int wakeup_events = event->attr.wakeup_events;
 
@@ -6018,6 +6038,38 @@ void perf_output_sample(struct perf_output_handle *handle,
 	}
 }
 
+static u64 perf_virt_to_phys(u64 virt)
+{
+	u64 phys_addr = 0;
+	struct page *p = NULL;
+
+	if (!virt)
+		return 0;
+
+	if (virt >= TASK_SIZE) {
+		/* If it's vmalloc()d memory, leave phys_addr as 0 */
+		if (virt_addr_valid((void *)(uintptr_t)virt) &&
+		    !(virt >= VMALLOC_START && virt < VMALLOC_END))
+			phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt);
+	} else {
+		/*
+		 * Walking the pages tables for user address.
+		 * Interrupts are disabled, so it prevents any tear down
+		 * of the page tables.
+		 * Try IRQ-safe __get_user_pages_fast first.
+		 * If failed, leave phys_addr as 0.
+		 */
+		if ((current->mm != NULL) &&
+		    (__get_user_pages_fast(virt, 1, 0, &p) == 1))
+			phys_addr = page_to_phys(p) + virt % PAGE_SIZE;
+
+		if (p)
+			put_page(p);
+	}
+
+	return phys_addr;
+}
+
 void perf_prepare_sample(struct perf_event_header *header,
 			 struct perf_sample_data *data,
 			 struct perf_event *event,
@@ -6136,6 +6188,9 @@ void perf_prepare_sample(struct perf_event_header *header,
 
 		header->size += size;
 	}
+
+	if (sample_type & PERF_SAMPLE_PHYS_ADDR)
+		data->phys_addr = perf_virt_to_phys(data->addr);
 }
 
 static void __always_inline
@@ -7287,6 +7342,11 @@ static void perf_log_throttle(struct perf_event *event, int enable)
 	perf_output_end(&handle);
 }
 
+void perf_event_itrace_started(struct perf_event *event)
+{
+	event->attach_state |= PERF_ATTACH_ITRACE;
+}
+
 static void perf_log_itrace_start(struct perf_event *event)
 {
 	struct perf_output_handle handle;
@@ -7302,7 +7362,7 @@ static void perf_log_itrace_start(struct perf_event *event)
 		event = event->parent;
 
 	if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) ||
-	    event->hw.itrace_started)
+	    event->attach_state & PERF_ATTACH_ITRACE)
 		return;
 
 	rec.header.type	= PERF_RECORD_ITRACE_START;
@@ -9890,6 +9950,11 @@ SYSCALL_DEFINE5(perf_event_open,
 			return -EINVAL;
 	}
 
+	/* Only privileged users can get physical addresses */
+	if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR) &&
+	    perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
 	if (!attr.sample_max_stack)
 		attr.sample_max_stack = sysctl_perf_event_max_stack;
 
diff --git a/kernel/events/internal.h b/kernel/events/internal.h
index 486fd78eb8d5..843e97047335 100644
--- a/kernel/events/internal.h
+++ b/kernel/events/internal.h
@@ -38,9 +38,9 @@ struct ring_buffer {
 	struct user_struct		*mmap_user;
 
 	/* AUX area */
-	local_t				aux_head;
+	long				aux_head;
 	local_t				aux_nest;
-	local_t				aux_wakeup;
+	long				aux_wakeup;	/* last aux_watermark boundary crossed by aux_head */
 	unsigned long			aux_pgoff;
 	int				aux_nr_pages;
 	int				aux_overwrite;
@@ -208,7 +208,7 @@ static inline int get_recursion_context(int *recursion)
 {
 	int rctx;
 
-	if (in_nmi())
+	if (unlikely(in_nmi()))
 		rctx = 3;
 	else if (in_irq())
 		rctx = 2;
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index ee97196bb151..af71a84e12ee 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -367,7 +367,7 @@ void *perf_aux_output_begin(struct perf_output_handle *handle,
 	if (WARN_ON_ONCE(local_xchg(&rb->aux_nest, 1)))
 		goto err_put;
 
-	aux_head = local_read(&rb->aux_head);
+	aux_head = rb->aux_head;
 
 	handle->rb = rb;
 	handle->event = event;
@@ -382,7 +382,7 @@ void *perf_aux_output_begin(struct perf_output_handle *handle,
 	 */
 	if (!rb->aux_overwrite) {
 		aux_tail = ACCESS_ONCE(rb->user_page->aux_tail);
-		handle->wakeup = local_read(&rb->aux_wakeup) + rb->aux_watermark;
+		handle->wakeup = rb->aux_wakeup + rb->aux_watermark;
 		if (aux_head - aux_tail < perf_aux_size(rb))
 			handle->size = CIRC_SPACE(aux_head, aux_tail, perf_aux_size(rb));
 
@@ -433,12 +433,12 @@ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
 		handle->aux_flags |= PERF_AUX_FLAG_OVERWRITE;
 
 		aux_head = handle->head;
-		local_set(&rb->aux_head, aux_head);
+		rb->aux_head = aux_head;
 	} else {
 		handle->aux_flags &= ~PERF_AUX_FLAG_OVERWRITE;
 
-		aux_head = local_read(&rb->aux_head);
-		local_add(size, &rb->aux_head);
+		aux_head = rb->aux_head;
+		rb->aux_head += size;
 	}
 
 	if (size || handle->aux_flags) {
@@ -450,11 +450,10 @@ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
 		                     handle->aux_flags);
 	}
 
-	aux_head = rb->user_page->aux_head = local_read(&rb->aux_head);
-
-	if (aux_head - local_read(&rb->aux_wakeup) >= rb->aux_watermark) {
+	rb->user_page->aux_head = rb->aux_head;
+	if (rb->aux_head - rb->aux_wakeup >= rb->aux_watermark) {
 		wakeup = true;
-		local_add(rb->aux_watermark, &rb->aux_wakeup);
+		rb->aux_wakeup = rounddown(rb->aux_head, rb->aux_watermark);
 	}
 
 	if (wakeup) {
@@ -478,22 +477,20 @@ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
 int perf_aux_output_skip(struct perf_output_handle *handle, unsigned long size)
 {
 	struct ring_buffer *rb = handle->rb;
-	unsigned long aux_head;
 
 	if (size > handle->size)
 		return -ENOSPC;
 
-	local_add(size, &rb->aux_head);
+	rb->aux_head += size;
 
-	aux_head = rb->user_page->aux_head = local_read(&rb->aux_head);
-	if (aux_head - local_read(&rb->aux_wakeup) >= rb->aux_watermark) {
+	rb->user_page->aux_head = rb->aux_head;
+	if (rb->aux_head - rb->aux_wakeup >= rb->aux_watermark) {
 		perf_output_wakeup(handle);
-		local_add(rb->aux_watermark, &rb->aux_wakeup);
-		handle->wakeup = local_read(&rb->aux_wakeup) +
-				 rb->aux_watermark;
+		rb->aux_wakeup = rounddown(rb->aux_head, rb->aux_watermark);
+		handle->wakeup = rb->aux_wakeup + rb->aux_watermark;
 	}
 
-	handle->head = aux_head;
+	handle->head = rb->aux_head;
 	handle->size -= size;
 
 	return 0;