| Message ID | 1386371325-1653-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 127361e..b89c2ee 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -213,8 +213,6 @@ static u64 scan_dispatch_log(u64 stop_tb) if (i == vpa->dtl_idx) return 0; while (i < vpa->dtl_idx) { - if (dtl_consumer) - dtl_consumer(dtl, i); dtb = dtl->timebase; tb_delta = dtl->enqueue_to_dispatch_time + dtl->ready_to_enqueue_time; @@ -227,6 +225,8 @@ static u64 scan_dispatch_log(u64 stop_tb) } if (dtb > stop_tb) break; + if (dtl_consumer) + dtl_consumer(dtl, i); stolen += tb_delta; ++i; ++dtl;
This is a note to let you know that I have just added a patch titled powerpc/pseries: Duplicate dtl entries sometimes sent to userspace to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.14. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From ff3e34f6f0b9ece307166655793f90cfe4ec264b Mon Sep 17 00:00:00 2001 From: Anton Blanchard <anton@samba.org> Date: Sun, 17 Nov 2013 11:39:05 +1100 Subject: powerpc/pseries: Duplicate dtl entries sometimes sent to userspace commit 84b073868b9d9e754ae48b828337633d1b386482 upstream. When reading from the dispatch trace log (dtl) userspace interface, I sometimes see duplicate entries. One example: 00000000 07 04 00 0c 00 00 48 44 00 00 00 00 00 00 00 00 00000010 00 0c a0 b4 16 83 6d 68 00 00 00 00 00 00 00 00 00000020 00 00 00 00 10 00 13 50 80 00 00 00 00 00 d0 32 00000030 07 04 00 0c 00 00 48 44 00 00 00 00 00 00 00 00 00000040 00 0c a0 b4 16 83 6d 68 00 00 00 00 00 00 00 00 00000050 00 00 00 00 10 00 13 50 80 00 00 00 00 00 d0 32 The problem is in scan_dispatch_log() where we call dtl_consumer() but bail out before incrementing the index. To fix this I moved dtl_consumer() after the timebase comparison. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [ kamal: backport to 3.8 (context) ] Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- arch/powerpc/kernel/time.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 1.8.3.2