Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Message-Id: <20190418084254.361284697@linutronix.de>
User-Agent: quilt/0.65
Date:   Thu, 18 Apr 2019 10:41:33 +0200
From:   Thomas Gleixner <tglx@linutronix.de>
To:     LKML <linux-kernel@vger.kernel.org>
Cc:     Josh Poimboeuf <jpoimboe@redhat.com>, x86@kernel.org,
        Andy Lutomirski <luto@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Alexander Potapenko <glider@google.com>, dm-devel@redhat.com,
        Mike Snitzer <snitzer@redhat.com>,
        Alasdair Kergon <agk@redhat.com>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Pekka Enberg <penberg@kernel.org>, linux-mm@kvack.org,
        David Rientjes <rientjes@google.com>,
        Christoph Lameter <cl@linux.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Andrey Ryabinin <aryabinin@virtuozzo.com>,
        kasan-dev@googlegroups.com,
        Mike Rapoport <rppt@linux.vnet.ibm.com>,
        Akinobu Mita <akinobu.mita@gmail.com>,
        iommu@lists.linux-foundation.org,
        Robin Murphy <robin.murphy@arm.com>,
        Christoph Hellwig <hch@lst.de>,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        Johannes Thumshirn <jthumshirn@suse.de>,
        David Sterba <dsterba@suse.com>, Chris Mason <clm@fb.com>,
        Josef Bacik <josef@toxicpanda.com>,
        linux-btrfs@vger.kernel.org, intel-gfx@lists.freedesktop.org,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        dri-devel@lists.freedesktop.org, David Airlie <airlied@linux.ie>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        linux-arch@vger.kernel.org
Subject: [patch V2 14/29] dm bufio: Simplify stack trace retrieval
References: <20190418084119.056416939@linutronix.de>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Replace the indirection through struct stack_trace with an invocation of
the storage array based interface.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: dm-devel@redhat.com
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Alasdair Kergon <agk@redhat.com>
---
 drivers/md/dm-bufio.c |   15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -150,7 +150,7 @@ struct dm_buffer {
 	void (*end_io)(struct dm_buffer *, blk_status_t);
 #ifdef CONFIG_DM_DEBUG_BLOCK_STACK_TRACING
 #define MAX_STACK 10
-	struct stack_trace stack_trace;
+	unsigned int stack_len;
 	unsigned long stack_entries[MAX_STACK];
 #endif
 };
@@ -232,11 +232,7 @@ static DEFINE_MUTEX(dm_bufio_clients_loc
 #ifdef CONFIG_DM_DEBUG_BLOCK_STACK_TRACING
 static void buffer_record_stack(struct dm_buffer *b)
 {
-	b->stack_trace.nr_entries = 0;
-	b->stack_trace.max_entries = MAX_STACK;
-	b->stack_trace.entries = b->stack_entries;
-	b->stack_trace.skip = 2;
-	save_stack_trace(&b->stack_trace);
+	b->stack_len = stack_trace_save(b->stack_entries, MAX_STACK, 2);
 }
 #endif
 
@@ -438,7 +434,7 @@ static struct dm_buffer *alloc_buffer(st
 	adjust_total_allocated(b->data_mode, (long)c->block_size);
 
 #ifdef CONFIG_DM_DEBUG_BLOCK_STACK_TRACING
-	memset(&b->stack_trace, 0, sizeof(b->stack_trace));
+	b->stack_len = 0;
 #endif
 	return b;
 }
@@ -1520,8 +1516,9 @@ static void drop_buffers(struct dm_bufio
 			DMERR("leaked buffer %llx, hold count %u, list %d",
 			      (unsigned long long)b->block, b->hold_count, i);
 #ifdef CONFIG_DM_DEBUG_BLOCK_STACK_TRACING
-			print_stack_trace(&b->stack_trace, 1);
-			b->hold_count = 0; /* mark unclaimed to avoid BUG_ON below */
+			stack_trace_print(b->stack_entries, b->stack_len, 1);
+			/* mark unclaimed to avoid BUG_ON below */
+			b->hold_count = 0;
 #endif
 		}