From: Stefan Priebe - Profihost AG <s.priebe@profihost.ag>
To: dsterba@suse.cz
Cc: "linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>
Subject: Re: Regression in btrfs: properly set the termination value of ctx->pos in readdir
Date: Wed, 11 Nov 2015 12:57:30 +0100 [thread overview]
Message-ID: <56432D2A.5040506@profihost.ag> (raw)
Hi,
the patch btrfs: properly set the termination value of ctx->pos in
readdir introduces a regression to me.
A lot of stuff runs in "endless" or long running loops.
An example strace looks like this:
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0g8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0g8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0h8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0h8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0i8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0i8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0j8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0j8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0k8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0k8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0l8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0l8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0m8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0m8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0n8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0n8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0o8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0o8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0p8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0p8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0q8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0q8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0r8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0r8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
newfstatat(AT_FDCWD, "changelog", {st_mode=S_IFREG|0644, st_size=148,
...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0s8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0s8\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...}, 56,
0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
{st_mode=S_IFREG|0644, st_size=148, ...}, AT_SYMLINK_NOFOLLOW) = 0
semop(98307, {{0, -1, SEM_UNDO}}, 1) = 0
msgsnd(0, {1,
"\3\0\0\0\247\r\0\0\2358\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...},
56, 0) = 0
msgrcv(32769, {1,
"\3\0\0\0\247\r\0\0\2358\0\0\0\0\0\0\0\0\0\0\345<\1\0\0\0\0\0\35\0\0\0"...},
56, 0, 0) = 56
semop(98307, {{0, 1, SEM_UNDO}}, 1) = 0
^C <unfinished ...>
Process 3495 detached
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
36.28 0.076892 10 7717 semop
24.25 0.051399 13 3858 newfstatat
21.48 0.045530 12 3858 msgsnd
17.46 0.036994 10 3859 msgrcv
0.52 0.001110 24 46 write
------ ----------- ----------- --------- --------- ----------------
100.00 0.211925 19338 total
Stefan
next reply other threads:[~2015-11-11 11:57 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-11-11 11:57 Stefan Priebe - Profihost AG [this message]
2015-11-11 12:22 ` Regression in btrfs: properly set the termination value of ctx->pos in readdir Holger Hoffstätte
2015-11-12 10:35 ` David Sterba
2015-11-12 13:09 ` David Sterba
2015-11-12 13:17 ` Holger Hoffstätte
2015-11-12 10:21 ` David Sterba
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