x86, UV: Remove cpumask_t from the stack

Remove the large stack-resident cpumask_t from
reset_with_ipi()'s stack by allocating one per uvhub.

Due to the limited size of the stack the potentially huge cpumask_t may
cause stack overrun.  We haven't seen it happen yet, but we need to make it
a practice not to push such structures onto the stack.

Signed-off-by: Cliff Wickman <cpw@sgi.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Link: http://lkml.kernel.org/r/20110621122242.832589130@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
cpw@sgi.com 2011-06-21 07:21:31 -05:00 committed by Ingo Molnar
parent a456eaab87
commit 442d392492
2 changed files with 16 additions and 4 deletions

View File

@ -488,6 +488,7 @@ struct bau_control {
struct bau_control *uvhub_master;
struct bau_control *socket_master;
struct ptc_stats *statp;
cpumask_t *cpumask;
unsigned long timeout_interval;
unsigned long set_bau_on_time;
atomic_t active_descriptor_count;

View File

@ -375,13 +375,13 @@ static void reset_with_ipi(struct pnmask *distribution, struct bau_control *bcp)
int pnode;
int apnode;
int maskbits;
cpumask_t mask;
int sender = bcp->cpu;
cpumask_t *mask = bcp->uvhub_master->cpumask;
struct bau_control *smaster = bcp->socket_master;
struct reset_args reset_args;
reset_args.sender = sender;
cpus_clear(mask);
cpus_clear(*mask);
/* find a single cpu for each uvhub in this distribution mask */
maskbits = sizeof(struct pnmask) * BITSPERBYTE;
/* each bit is a pnode relative to the partition base pnode */
@ -391,11 +391,11 @@ static void reset_with_ipi(struct pnmask *distribution, struct bau_control *bcp)
continue;
apnode = pnode + bcp->partition_base_pnode;
cpu = pnode_to_first_cpu(apnode, smaster);
cpu_set(cpu, mask);
cpu_set(cpu, *mask);
}
/* IPI all cpus; preemption is already disabled */
smp_call_function_many(&mask, do_reset, (void *)&reset_args, 1);
smp_call_function_many(mask, do_reset, (void *)&reset_args, 1);
return;
}
@ -1695,6 +1695,16 @@ static void make_per_cpu_thp(struct bau_control *smaster)
}
}
/*
* Each uvhub is to get a local cpumask.
*/
static void make_per_hub_cpumask(struct bau_control *hmaster)
{
int sz = sizeof(cpumask_t);
hmaster->cpumask = kzalloc_node(sz, GFP_KERNEL, hmaster->osnode);
}
/*
* Initialize all the per_cpu information for the cpu's on a given socket,
* given what has been gathered into the socket_desc struct.
@ -1765,6 +1775,7 @@ static int __init summarize_uvhub_sockets(int nuvhubs,
socket++;
socket_mask = (socket_mask >> 1);
}
make_per_hub_cpumask(hmaster);
}
return 0;
}