lkml.org 
[lkml]   [2018]   [Feb]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH] coresight replicator: set default y after Kconfig rename
On Thu, 8 Feb 2018 18:01:21 +0000
Suzuki K Poulose <Suzuki.Poulose@arm.com> wrote:

> On 08/02/18 17:22, Kim Phillips wrote:
> > On Thu, 8 Feb 2018 08:59:30 -0700
> > Mathieu Poirier <mathieu.poirier@linaro.org> wrote:
> >
> >> On 7 February 2018 at 14:03, Kim Phillips <kim.phillips@arm.com> wrote:
> >>> Commit 1c8859848dbb ("coresight replicator: Cleanup programmable
> >>> replicator naming") changed the Kconfig symbol name from
> >>> QCOM_REPLICATOR, which, whilst not in the single arm64 defconfig,
> >>> was being set in my juno build script, which left the new symbol unset,
> >>> causing the following unexpected grief:
> >>>
> >>> # ./perf record -vvv -C 0 -e cs_etm/@20070000.etr/ --per-thread true
> >>> ..<snip>..
> >>> sys_perf_event_open: pid -1 cpu 0 group_fd -1 flags 0x8 = 5
> >>> mmap size 528384B
> >>> AUX area mmap length 4194304
> >>> perf event ring buffer mmapped per cpu
> >>> failed to mmap AUX area
> >>> failed to mmap with 12 (Cannot allocate memory)
> >>>
> >>> Make it default y to help not surprise unsuspecting users.
> >>>
> >>> Fixes: 1c8859848dbb ("coresight replicator: Cleanup programmable replicator naming")
> >>> Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
> >>> Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
> >>> Signed-off-by: Kim Phillips <kim.phillips@arm.com>
> >>> ---
> >>> drivers/hwtracing/coresight/Kconfig | 1 +
> >>> 1 file changed, 1 insertion(+)
> >>>
> >>> diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
> >>> index ef9cb3c164e1..b94bbd95efa6 100644
> >>> --- a/drivers/hwtracing/coresight/Kconfig
> >>> +++ b/drivers/hwtracing/coresight/Kconfig
> >>> @@ -73,6 +73,7 @@ config CORESIGHT_SOURCE_ETM4X
> >>> config CORESIGHT_DYNAMIC_REPLICATOR
> >>> bool "CoreSight Programmable Replicator driver"
> >>> depends on CORESIGHT_LINKS_AND_SINKS
> >>> + default y
> >>> help
> >>> This enables support for dynamic CoreSight replicator link driver.
> >>> The programmable ATB replicator allows independent filtering of the
> >>
> >> As I said before don't see why it needs to be treated differently than other CS
> >> blocks
> >
> > I don't think it does either, but this one is special since it recently
> > underwent a rename, which breaks its users that were setting the old
> > name in their config builds. The default y keeps it set in those
> > cases, thereby discontinuing any such regression.
>
> I don't think the kernel CONFIG symbols are part of the kernel ABI. So,
> unfortunately the users have to take care of making sure they select what
> they need.

Right, sorry, I wan't referring to a kernel ABI regression :) Think of
it as just trying to make Coresight easier to configure, and in this
particular case, given Coresight Kconfig symbol name volatility.

Kim

\
 
 \ /
  Last update: 2018-02-08 20:24    [W:0.053 / U:0.728 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site