rpms
/
kernel
2
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Add patch to fix high cpu usage on direct_read kernfs files (rhbz 1202362)

This commit is contained in:
Josh Boyer 2015-03-19 09:11:13 -04:00
parent cde0b0eb7a
commit 4751d6e935
2 changed files with 47 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
kernel.spec
View File

@ -647,6 +647,9 @@ Patch26167: IB-core-Prevent-integer-overflow-in-ib_umem_get-addr.patch
#rhbz 1201532
Patch26168: HID-multitouch-add-support-of-clickpads.patch
#rhbz 1202362
Patch26169: kernfs-handle-poll-correctly-on-direct_read-files.patch
# git clone ssh://git.fedorahosted.org/git/kernel-arm64.git, git diff master...devel
Patch30000: kernel-arm64.patch
@ -1402,6 +1405,9 @@ ApplyPatch IB-core-Prevent-integer-overflow-in-ib_umem_get-addr.patch
#rhbz 1201532
ApplyPatch HID-multitouch-add-support-of-clickpads.patch
#rhbz 1202362
ApplyPatch kernfs-handle-poll-correctly-on-direct_read-files.patch
%if 0%{?aarch64patches}
ApplyPatch kernel-arm64.patch
%ifnarch aarch64 # this is stupid, but i want to notice before secondary koji does.
@ -2259,6 +2265,9 @@ fi
#
#
%changelog
* Thu Mar 19 2015 Josh Boyer <jwboyer@fedoraproject.org>
- Add patch to fix high cpu usage on direct_read kernfs files (rhbz 1202362)
* Wed Mar 18 2015 Jarod Wilson <jwilson@fedoraproject.org>
- Fix kernel-uname-r Requires/Provides variant mismatches

38
kernfs-handle-poll-correctly-on-direct_read-files.patch Normal file
View File

@ -0,0 +1,38 @@
From: NeilBrown <neilb@suse.de>
Date: Mon, 16 Mar 2015 10:44:52 +1100
Subject: [PATCH] kernfs: handle poll correctly on 'direct_read' files.
Kernfs supports two styles of read: direct_read and seqfile_read.
The latter supports 'poll' correctly thanks to the update of
'->event' in kernfs_seq_show.
The former does not as '->event' is never updated on a read.
So add an appropriate update in kernfs_file_direct_read().
This was noticed because some 'md' sysfs attributes were
recently changed to use direct reads.
Reported-by: Prakash Punnoor <prakash@punnoor.de>
Reported-by: Torsten Kaiser <just.for.lkml@googlemail.com>
Fixes: 750f199ee8b578062341e6ddfe36c59ac8ff2dcb
Signed-off-by: NeilBrown <neilb@suse.de>
---
fs/kernfs/file.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index b684e8a132e6..2bacb9988566 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -207,6 +207,7 @@ static ssize_t kernfs_file_direct_read(struct kernfs_open_file *of,
goto out_free;
}
+ of->event = atomic_read(&of->kn->attr.open->event);
ops = kernfs_ops(of->kn);
if (ops->read)
len = ops->read(of, buf, len, *ppos);
--
2.1.0