| Message ID | 1405111845-3588-1-git-send-email-ard.biesheuvel@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Fri, 11 Jul 2014 22:50:45 +0200 Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote: > Commit f7f7bac9cb1c ("rcu: Have the RCU tracepoints use the tracepoint_string > infrastructure") unconditionally populates the __tracepoint_str input section, > but this section is not assigned an output section if CONFIG_TRACING is not set. > This results in the __tracepoint_str turning up in unexpected places, i.e., > after _edata. > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> > Cc: rostedt@goodmis.org > Cc: paulmck@linux.vnet.ibm.com > --- > v2: > - s/DEFINE_TPS/DEFINE_RCU_TPS/ > > kernel/rcu/tree.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > index f1ba77363fbb..eec9f3d6f506 100644 > --- a/kernel/rcu/tree.c > +++ b/kernel/rcu/tree.c > @@ -79,9 +79,16 @@ static struct lock_class_key rcu_fqs_class[RCU_NUM_LVLS]; > * the tracing userspace tools to be able to decipher the string > * address to the matching string. > */ > +#ifdef CONFIG_TRACING > +#define DEFINE_RCU_TPS(sname) \ > +static const char *tp_##sname##_varname __used __tracepoint_string = sname##_varname; > +#else > +#define DEFINE_RCU_TPS(sname) > +#endif > + > #define RCU_STATE_INITIALIZER(sname, sabbr, cr) \ > static char sname##_varname[] = #sname; \ > -static const char *tp_##sname##_varname __used __tracepoint_string = sname##_varname; \ > +DEFINE_RCU_TPS(sname) \ > struct rcu_state sname##_state = { \ > .level = { &sname##_state.node[0] }, \ > .call = cr, \ Looking at this a bit deeper (actually looking at it in the context of the code), we can make this even better. #ifdef CONFIG_TRACING # define DEFINE_RCU_TPS(sname) \ static char sname##_varname[] = #sname; \ static const char *tp_##sname##_varname __used __tracepoint_string = sname##_varname; # define RCU_STATE_NAME(sname) sname##_varname; #else # define DEFINE_RCU_TPS(sname) # define RCU_STATE_NAME(sname) __stringify(sname) #endif Then add: .name = RCU_STATE_NAME(sname), \ This will get rid of the sname##_varname variable as well. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index f1ba77363fbb..eec9f3d6f506 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -79,9 +79,16 @@ static struct lock_class_key rcu_fqs_class[RCU_NUM_LVLS]; * the tracing userspace tools to be able to decipher the string * address to the matching string. */ +#ifdef CONFIG_TRACING +#define DEFINE_RCU_TPS(sname) \ +static const char *tp_##sname##_varname __used __tracepoint_string = sname##_varname; +#else +#define DEFINE_RCU_TPS(sname) +#endif + #define RCU_STATE_INITIALIZER(sname, sabbr, cr) \ static char sname##_varname[] = #sname; \ -static const char *tp_##sname##_varname __used __tracepoint_string = sname##_varname; \ +DEFINE_RCU_TPS(sname) \ struct rcu_state sname##_state = { \ .level = { &sname##_state.node[0] }, \ .call = cr, \
Commit f7f7bac9cb1c ("rcu: Have the RCU tracepoints use the tracepoint_string infrastructure") unconditionally populates the __tracepoint_str input section, but this section is not assigned an output section if CONFIG_TRACING is not set. This results in the __tracepoint_str turning up in unexpected places, i.e., after _edata. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: rostedt@goodmis.org Cc: paulmck@linux.vnet.ibm.com --- v2: - s/DEFINE_TPS/DEFINE_RCU_TPS/ kernel/rcu/tree.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)