All of lore.kernel.org
 help / color / mirror / Atom feed
From: Prakash Gupta <guptap@codeaurora.org>
To: akpm@linux-foundation.org, mhocko@suse.com, vbabka@suse.cz,
	will.deacon@arm.com, catalin.marinas@arm.com,
	iamjoonsoo.kim@lge.com, rmk+kernel@arm.linux.org.uk,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org
Cc: Prakash Gupta <guptap@codeaurora.org>
Subject: [PATCH 2/2] mm, page_owner: Skip unnecessary stack_trace entries
Date: Wed, 30 Aug 2017 13:02:23 +0530	[thread overview]
Message-ID: <1504078343-28754-2-git-send-email-guptap@codeaurora.org> (raw)
In-Reply-To: <1504078343-28754-1-git-send-email-guptap@codeaurora.org>

The page_owner stacktrace always begin as follows:

[<ffffff987bfd48f4>] save_stack+0x40/0xc8
[<ffffff987bfd4da8>] __set_page_owner+0x3c/0x6c

These two entries do not provide any useful information and limits the
available stacktrace depth.  The page_owner stacktrace was skipping caller
function from stack entries but this was missed with commit f2ca0b557107
("mm/page_owner: use stackdepot to store stacktrace")

Example page_owner entry after the patch:

Page allocated via order 0, mask 0x8(ffffff80085fb714)
PFN 654411 type Movable Block 639 type CMA Flags 0x0(ffffffbe5c7f12c0)
[<ffffff9b64989c14>] post_alloc_hook+0x70/0x80
...
[<ffffff9b651216e8>] msm_comm_try_state+0x5f8/0x14f4
[<ffffff9b6512486c>] msm_vidc_open+0x5e4/0x7d0
[<ffffff9b65113674>] msm_v4l2_open+0xa8/0x224

Fixes: f2ca0b557107 ("mm/page_owner: use stackdepot to store stacktrace")
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>
---
 mm/page_owner.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/page_owner.c b/mm/page_owner.c
index 10d16fc45bd9..75b7c39bf1df 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -139,7 +139,7 @@ static noinline depot_stack_handle_t save_stack(gfp_t flags)
 		.nr_entries = 0,
 		.entries = entries,
 		.max_entries = PAGE_OWNER_STACK_DEPTH,
-		.skip = 0
+		.skip = 2
 	};
 	depot_stack_handle_t handle;
 
-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
member of the Code Aurora Forum, hosted by The Linux Foundation

WARNING: multiple messages have this Message-ID
From: Prakash Gupta <guptap@codeaurora.org>
To: akpm@linux-foundation.org, mhocko@suse.com, vbabka@suse.cz,
	will.deacon@arm.com, catalin.marinas@arm.com,
	iamjoonsoo.kim@lge.com, rmk+kernel@arm.linux.org.uk,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org
Cc: Prakash Gupta <guptap@codeaurora.org>
Subject: [PATCH 2/2] mm, page_owner: Skip unnecessary stack_trace entries
Date: Wed, 30 Aug 2017 13:02:23 +0530	[thread overview]
Message-ID: <1504078343-28754-2-git-send-email-guptap@codeaurora.org> (raw)
In-Reply-To: <1504078343-28754-1-git-send-email-guptap@codeaurora.org>

The page_owner stacktrace always begin as follows:

[<ffffff987bfd48f4>] save_stack+0x40/0xc8
[<ffffff987bfd4da8>] __set_page_owner+0x3c/0x6c

These two entries do not provide any useful information and limits the
available stacktrace depth.  The page_owner stacktrace was skipping caller
function from stack entries but this was missed with commit f2ca0b557107
("mm/page_owner: use stackdepot to store stacktrace")

Example page_owner entry after the patch:

Page allocated via order 0, mask 0x8(ffffff80085fb714)
PFN 654411 type Movable Block 639 type CMA Flags 0x0(ffffffbe5c7f12c0)
[<ffffff9b64989c14>] post_alloc_hook+0x70/0x80
...
[<ffffff9b651216e8>] msm_comm_try_state+0x5f8/0x14f4
[<ffffff9b6512486c>] msm_vidc_open+0x5e4/0x7d0
[<ffffff9b65113674>] msm_v4l2_open+0xa8/0x224

Fixes: f2ca0b557107 ("mm/page_owner: use stackdepot to store stacktrace")
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>
---
 mm/page_owner.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/page_owner.c b/mm/page_owner.c
index 10d16fc45bd9..75b7c39bf1df 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -139,7 +139,7 @@ static noinline depot_stack_handle_t save_stack(gfp_t flags)
 		.nr_entries = 0,
 		.entries = entries,
 		.max_entries = PAGE_OWNER_STACK_DEPTH,
-		.skip = 0
+		.skip = 2
 	};
 	depot_stack_handle_t handle;
 
-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
member of the Code Aurora Forum, hosted by The Linux Foundation

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2017-08-30  7:33 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-30  7:32 [PATCH 1/2] arm64: stacktrace: avoid listing stacktrace functions in stacktrace Prakash Gupta
2017-08-30  7:32 ` Prakash Gupta
2017-08-30  7:32 ` Prakash Gupta [this message]
2017-08-30  7:32   ` [PATCH 2/2] mm, page_owner: Skip unnecessary stack_trace entries Prakash Gupta
2017-08-31  7:34   ` Vlastimil Babka
2017-08-31  7:34     ` Vlastimil Babka
2017-09-01  5:00     ` Prakash Gupta
2017-09-01  5:00       ` Prakash Gupta
2017-08-30 20:28 ` [PATCH 1/2] arm64: stacktrace: avoid listing stacktrace functions in stacktrace Andrew Morton
2017-08-30 20:28   ` Andrew Morton
2017-08-31  6:28   ` Prakash Gupta
2017-08-31  6:28     ` Prakash Gupta
2017-09-04 10:29   ` Catalin Marinas
2017-09-04 10:29     ` Catalin Marinas

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1504078343-28754-2-git-send-email-guptap@codeaurora.org \
    --to=guptap@codeaurora.org \
    --cc=akpm@linux-foundation.org \
    --cc=catalin.marinas@arm.com \
    --cc=iamjoonsoo.kim@lge.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@suse.com \
    --cc=rmk+kernel@arm.linux.org.uk \
    --cc=vbabka@suse.cz \
    --cc=will.deacon@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.