Messages in this thread Patch in this message | | | Date | Thu, 7 May 2009 09:21:28 GMT | From | tip-bot for Markus Metzger <> | Subject | [tip:tracing/core] x86, bts: use atomic memory allocation |
| |
Commit-ID: c78a3956b982418186e40978a51636a2b43221bc Gitweb: http://git.kernel.org/tip/c78a3956b982418186e40978a51636a2b43221bc Author: Markus Metzger <markus.t.metzger@intel.com> AuthorDate: Wed, 18 Mar 2009 19:27:00 +0100 Committer: Ingo Molnar <mingo@elte.hu> CommitDate: Thu, 19 Mar 2009 14:02:47 +0100
x86, bts: use atomic memory allocation
Ds_request_bts() needs to allocate memory. It uses GFP_KERNEL.
Hw-branch-tracer calls ds_request_bts() within on_each_cpu().
Use atomic memory allocation to allow it to be used in that context.
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com> LKML-Reference: <20090318192700.A6038@sedona.ch.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
--- arch/x86/kernel/ds.c | 21 +++++++++++++++++---- 1 files changed, 17 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kernel/ds.c b/arch/x86/kernel/ds.c index 5fd5333..b1d6e1f 100644 --- a/arch/x86/kernel/ds.c +++ b/arch/x86/kernel/ds.c @@ -255,8 +255,13 @@ static inline struct ds_context *ds_get_context(struct task_struct *task) struct ds_context *new_context = NULL; unsigned long irq; - /* Chances are small that we already have a context. */ - new_context = kzalloc(sizeof(*new_context), GFP_KERNEL); + /* + * Chances are small that we already have a context. + * + * Contexts for per-cpu tracing are allocated using + * smp_call_function(). We must not sleep. + */ + new_context = kzalloc(sizeof(*new_context), GFP_ATOMIC); if (!new_context) return NULL; @@ -662,8 +667,12 @@ struct bts_tracer *ds_request_bts(struct task_struct *task, if (ovfl) goto out; + /* + * Per-cpu tracing is typically requested using smp_call_function(). + * We must not sleep. + */ error = -ENOMEM; - tracer = kzalloc(sizeof(*tracer), GFP_KERNEL); + tracer = kzalloc(sizeof(*tracer), GFP_ATOMIC); if (!tracer) goto out; tracer->ovfl = ovfl; @@ -722,8 +731,12 @@ struct pebs_tracer *ds_request_pebs(struct task_struct *task, if (ovfl) goto out; + /* + * Per-cpu tracing is typically requested using smp_call_function(). + * We must not sleep. + */ error = -ENOMEM; - tracer = kzalloc(sizeof(*tracer), GFP_KERNEL); + tracer = kzalloc(sizeof(*tracer), GFP_ATOMIC); if (!tracer) goto out; tracer->ovfl = ovfl;
| |