On 03/22/2017 09:07 AM, Aneesh Kumar K.V wrote: > As we start supporting larger address space (>128TB), we want to give > architecture a control on max task size of an application which is different > from the TASK_SIZE. For ex: ppc64 needs to track the base page size of a segment > and it is copied from mm_context_t to PACA on each context switch. If we know that > application has not used an address range above 128TB we only need to copy > details about 128TB range to PACA. This will help in improving context switch > performance by avoiding larger copy operation. > > Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Cc: linux-mm@xxxxxxxxx > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxxxxxxx> > --- > fs/exec.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/fs/exec.c b/fs/exec.c > index 65145a3df065..5550a56d03c3 100644 > --- a/fs/exec.c > +++ b/fs/exec.c > @@ -1308,6 +1308,14 @@ void would_dump(struct linux_binprm *bprm, struct file *file) > } > EXPORT_SYMBOL(would_dump); > > +#ifndef arch_init_task_size > +static inline void arch_init_task_size(void) > +{ > + current->mm->task_size = TASK_SIZE; > +} > +#define arch_init_task_size arch_init_task_size > +#endif Why not a proper CONFIG_ARCH_DEFINED_TASK_SIZE kind of option for this ? Also are there no assumptions about task current->mm->size being TASK_SIZE in other places which might get broken ? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>