| Message ID | 1508837889-16932-5-git-send-email-byungchul.park@lge.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
* Byungchul Park <byungchul.park@lge.com> wrote: > Make whether to allow recording full stack, in cross-release feature, > switchable at boot time via a kernel parameter, 'crossrelease_fullstack'. > In case of a splat with no stack trace, one could just reboot and set > the kernel parameter to get the full data without having to recompile > the kernel. > > Change CONFIG_CROSSRELEASE_STACK_TRACE default from N to Y, and > introduce the new kernel parameter. > > Signed-off-by: Byungchul Park <byungchul.park@lge.com> > --- > Documentation/admin-guide/kernel-parameters.txt | 3 +++ > kernel/locking/lockdep.c | 18 ++++++++++++++++-- > lib/Kconfig.debug | 5 +++-- > 3 files changed, 22 insertions(+), 4 deletions(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index ead7f40..4107b01 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -709,6 +709,9 @@ > It will be ignored when crashkernel=X,high is not used > or memory reserved is below 4G. > > + crossrelease_fullstack > + [KNL] Allow to record full stack trace in cross-release > + > cryptomgr.notests > [KNL] Disable crypto self-tests > > diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c > index 5c2ddf2..feba887 100644 > --- a/kernel/locking/lockdep.c > +++ b/kernel/locking/lockdep.c > @@ -76,6 +76,15 @@ > #define lock_stat 0 > #endif > > +static int crossrelease_fullstack; > +static int __init allow_crossrelease_fullstack(char *str) > +{ > + crossrelease_fullstack = 1; > + return 0; > +} > + > +early_param("crossrelease_fullstack", allow_crossrelease_fullstack); > + > /* > * lockdep_lock: protects the lockdep graph, the hashes and the > * class/list/hash allocators. > @@ -4864,8 +4873,13 @@ static void add_xhlock(struct held_lock *hlock) > xhlock->trace.max_entries = MAX_XHLOCK_TRACE_ENTRIES; > xhlock->trace.entries = xhlock->trace_entries; > #ifdef CONFIG_CROSSRELEASE_STACK_TRACE > - xhlock->trace.skip = 3; > - save_stack_trace(&xhlock->trace); > + if (crossrelease_fullstack) { > + xhlock->trace.skip = 3; > + save_stack_trace(&xhlock->trace); > + } else { > + xhlock->trace.nr_entries = 1; > + xhlock->trace.entries[0] = hlock->acquire_ip; > + } > #else > xhlock->trace.nr_entries = 1; > xhlock->trace.entries[0] = hlock->acquire_ip; > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug > index fe8fceb..132536d 100644 > --- a/lib/Kconfig.debug > +++ b/lib/Kconfig.debug > @@ -1228,7 +1228,7 @@ config LOCKDEP_COMPLETIONS > config CROSSRELEASE_STACK_TRACE > bool "Record more than one entity of stack trace in crossrelease" > depends on LOCKDEP_CROSSRELEASE > - default n > + default y > help > The lockdep "cross-release" feature needs to record stack traces > (of calling functions) for all acquisitions, for eventual later > @@ -1238,7 +1238,8 @@ config CROSSRELEASE_STACK_TRACE > full analysis. This option turns on the saving of the full stack > trace entries. > > - If unsure, say N. > + To make the feature actually on, set "crossrelease_fullstack" > + kernel parameter, too. > > config DEBUG_LOCKDEP > bool "Lock dependency engine debugging" This is really unnecessarily complex. The proper logic is to introduce the crossrelease_fullstack boot parameter, and to also have a Kconfig option that enables it: CONFIG_BOOTPARAM_LOCKDEP_CROSSRELEASE_FULLSTACK=y No #ifdefs please - just an "if ()" branch dependent on the current value of crossrelease_fullstack. Thanks, Ingo
On Tue, Oct 24, 2017 at 12:08:58PM +0200, Ingo Molnar wrote: > This is really unnecessarily complex. I mis-understood your suggestion. I will change it. > The proper logic is to introduce the crossrelease_fullstack boot parameter, and to > also have a Kconfig option that enables it: > > CONFIG_BOOTPARAM_LOCKDEP_CROSSRELEASE_FULLSTACK=y > > No #ifdefs please - just an "if ()" branch dependent on the current value of > crossrelease_fullstack. Ok. I will. Thanks, Byungchul > Thanks, > > Ingo
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index ead7f40..4107b01 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -709,6 +709,9 @@ It will be ignored when crashkernel=X,high is not used or memory reserved is below 4G. + crossrelease_fullstack + [KNL] Allow to record full stack trace in cross-release + cryptomgr.notests [KNL] Disable crypto self-tests diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 5c2ddf2..feba887 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -76,6 +76,15 @@ #define lock_stat 0 #endif +static int crossrelease_fullstack; +static int __init allow_crossrelease_fullstack(char *str) +{ + crossrelease_fullstack = 1; + return 0; +} + +early_param("crossrelease_fullstack", allow_crossrelease_fullstack); + /* * lockdep_lock: protects the lockdep graph, the hashes and the * class/list/hash allocators. @@ -4864,8 +4873,13 @@ static void add_xhlock(struct held_lock *hlock) xhlock->trace.max_entries = MAX_XHLOCK_TRACE_ENTRIES; xhlock->trace.entries = xhlock->trace_entries; #ifdef CONFIG_CROSSRELEASE_STACK_TRACE - xhlock->trace.skip = 3; - save_stack_trace(&xhlock->trace); + if (crossrelease_fullstack) { + xhlock->trace.skip = 3; + save_stack_trace(&xhlock->trace); + } else { + xhlock->trace.nr_entries = 1; + xhlock->trace.entries[0] = hlock->acquire_ip; + } #else xhlock->trace.nr_entries = 1; xhlock->trace.entries[0] = hlock->acquire_ip; diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index fe8fceb..132536d 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1228,7 +1228,7 @@ config LOCKDEP_COMPLETIONS config CROSSRELEASE_STACK_TRACE bool "Record more than one entity of stack trace in crossrelease" depends on LOCKDEP_CROSSRELEASE - default n + default y help The lockdep "cross-release" feature needs to record stack traces (of calling functions) for all acquisitions, for eventual later @@ -1238,7 +1238,8 @@ config CROSSRELEASE_STACK_TRACE full analysis. This option turns on the saving of the full stack trace entries. - If unsure, say N. + To make the feature actually on, set "crossrelease_fullstack" + kernel parameter, too. config DEBUG_LOCKDEP bool "Lock dependency engine debugging"
Make whether to allow recording full stack, in cross-release feature, switchable at boot time via a kernel parameter, 'crossrelease_fullstack'. In case of a splat with no stack trace, one could just reboot and set the kernel parameter to get the full data without having to recompile the kernel. Change CONFIG_CROSSRELEASE_STACK_TRACE default from N to Y, and introduce the new kernel parameter. Signed-off-by: Byungchul Park <byungchul.park@lge.com> --- Documentation/admin-guide/kernel-parameters.txt | 3 +++ kernel/locking/lockdep.c | 18 ++++++++++++++++-- lib/Kconfig.debug | 5 +++-- 3 files changed, 22 insertions(+), 4 deletions(-)