freebsd-nq/sys/sparc64/include/tlb.h
Jake Burkholder f1bb97a884 Fix a deadlock condition with tlb shootdown ipi delivery. Since ipis are
not blocked by raising the pil, a reciever may be interrupted while holding
a spinlock.  If the sender does not defer interrupts throughout the entire
operation it may be interrupted and try to acquire a spinlock held by a
reciever, leading to a deadlock due to the synchronization used by the
ipi handlers themselves.

Submitted by:	tmm
2002-03-23 04:20:00 +00:00

197 lines
6.0 KiB
C

/*-
* Copyright (c) 2001 Jake Burkholder.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _MACHINE_TLB_H_
#define _MACHINE_TLB_H_
#define TLB_SLOT_COUNT 64 /* XXX */
#define TLB_SLOT_TSB_KERNEL_MIN 62 /* XXX */
#define TLB_SLOT_KERNEL 63 /* XXX */
#define TLB_DAR_SLOT_SHIFT (3)
#define TLB_DAR_SLOT(slot) ((slot) << TLB_DAR_SLOT_SHIFT)
#define TAR_VPN_SHIFT (13)
#define TAR_CTX_MASK ((1 << TAR_VPN_SHIFT) - 1)
#define TLB_TAR_VA(va) ((va) & ~TAR_CTX_MASK)
#define TLB_TAR_CTX(ctx) ((ctx) & TAR_CTX_MASK)
#define TLB_DEMAP_ID_SHIFT (4)
#define TLB_DEMAP_ID_PRIMARY (0)
#define TLB_DEMAP_ID_SECONDARY (1)
#define TLB_DEMAP_ID_NUCLEUS (2)
#define TLB_DEMAP_TYPE_SHIFT (6)
#define TLB_DEMAP_TYPE_PAGE (0)
#define TLB_DEMAP_TYPE_CONTEXT (1)
#define TLB_DEMAP_VA(va) ((va) & ~PAGE_MASK)
#define TLB_DEMAP_ID(id) ((id) << TLB_DEMAP_ID_SHIFT)
#define TLB_DEMAP_TYPE(type) ((type) << TLB_DEMAP_TYPE_SHIFT)
#define TLB_DEMAP_PAGE (TLB_DEMAP_TYPE(TLB_DEMAP_TYPE_PAGE))
#define TLB_DEMAP_CONTEXT (TLB_DEMAP_TYPE(TLB_DEMAP_TYPE_CONTEXT))
#define TLB_DEMAP_PRIMARY (TLB_DEMAP_ID(TLB_DEMAP_ID_PRIMARY))
#define TLB_DEMAP_SECONDARY (TLB_DEMAP_ID(TLB_DEMAP_ID_SECONDARY))
#define TLB_DEMAP_NUCLEUS (TLB_DEMAP_ID(TLB_DEMAP_ID_NUCLEUS))
#define TLB_CTX_KERNEL (0)
#define TLB_CTX_USER_MIN (1)
#define TLB_CTX_USER_MAX (8192)
#define TLB_DTLB (1 << 0)
#define TLB_ITLB (1 << 1)
#define MMU_SFSR_ASI_SHIFT (16)
#define MMU_SFSR_FT_SHIFT (7)
#define MMU_SFSR_E_SHIFT (6)
#define MMU_SFSR_CT_SHIFT (4)
#define MMU_SFSR_PR_SHIFT (3)
#define MMU_SFSR_W_SHIFT (2)
#define MMU_SFSR_OW_SHIFT (1)
#define MMU_SFSR_FV_SHIFT (0)
#define MMU_SFSR_ASI_SIZE (8)
#define MMU_SFSR_FT_SIZE (6)
#define MMU_SFSR_CT_SIZE (2)
#define MMU_SFSR_W (1L << MMU_SFSR_W_SHIFT)
extern int kernel_tlb_slots;
extern struct tte *kernel_ttes;
/*
* Some tlb operations must be atomic, so no interrupt or trap can be allowed
* while they are in progress. Traps should not happen, but interrupts need to
* be explicitely disabled. critical_enter() cannot be used here, since it only
* disables soft interrupts.
*/
static __inline void
tlb_context_demap(struct pmap *pm)
{
void *cookie;
u_long s;
/*
* It is important that we are not interrupted or preempted while
* doing the IPIs. The interrupted CPU may hold locks, and since
* it will wait for the CPU that sent the IPI, this can lead
* to a deadlock when an interrupt comes in on that CPU and it's
* handler tries to grab one of that locks. This will only happen for
* spin locks, but these IPI types are delivered even if normal
* interrupts are disabled, so the lock critical section will not
* protect the target processor from entering the IPI handler with
* the lock held.
*/
critical_enter();
cookie = ipi_tlb_context_demap(pm);
if (pm->pm_active & PCPU_GET(cpumask)) {
KASSERT(pm->pm_context[PCPU_GET(cpuid)] != -1,
("tlb_context_demap: inactive pmap?"));
s = intr_disable();
stxa(TLB_DEMAP_PRIMARY | TLB_DEMAP_CONTEXT, ASI_DMMU_DEMAP, 0);
stxa(TLB_DEMAP_PRIMARY | TLB_DEMAP_CONTEXT, ASI_IMMU_DEMAP, 0);
membar(Sync);
intr_restore(s);
}
ipi_wait(cookie);
critical_exit();
}
static __inline void
tlb_page_demap(u_int tlb, struct pmap *pm, vm_offset_t va)
{
u_long flags;
void *cookie;
u_long s;
critical_enter();
cookie = ipi_tlb_page_demap(tlb, pm, va);
if (pm->pm_active & PCPU_GET(cpumask)) {
KASSERT(pm->pm_context[PCPU_GET(cpuid)] != -1,
("tlb_page_demap: inactive pmap?"));
if (pm == kernel_pmap)
flags = TLB_DEMAP_NUCLEUS | TLB_DEMAP_PAGE;
else
flags = TLB_DEMAP_PRIMARY | TLB_DEMAP_PAGE;
s = intr_disable();
if (tlb & TLB_DTLB) {
stxa(TLB_DEMAP_VA(va) | flags, ASI_DMMU_DEMAP, 0);
membar(Sync);
}
if (tlb & TLB_ITLB) {
stxa(TLB_DEMAP_VA(va) | flags, ASI_IMMU_DEMAP, 0);
membar(Sync);
}
intr_restore(s);
}
ipi_wait(cookie);
critical_exit();
}
static __inline void
tlb_range_demap(struct pmap *pm, vm_offset_t start, vm_offset_t end)
{
vm_offset_t va;
void *cookie;
u_long flags;
u_long s;
critical_enter();
cookie = ipi_tlb_range_demap(pm, start, end);
if (pm->pm_active & PCPU_GET(cpumask)) {
KASSERT(pm->pm_context[PCPU_GET(cpuid)] != -1,
("tlb_range_demap: inactive pmap?"));
if (pm == kernel_pmap)
flags = TLB_DEMAP_NUCLEUS | TLB_DEMAP_PAGE;
else
flags = TLB_DEMAP_PRIMARY | TLB_DEMAP_PAGE;
s = intr_disable();
for (va = start; va < end; va += PAGE_SIZE) {
stxa(TLB_DEMAP_VA(va) | flags, ASI_DMMU_DEMAP, 0);
stxa(TLB_DEMAP_VA(va) | flags, ASI_IMMU_DEMAP, 0);
membar(Sync);
}
intr_restore(s);
}
ipi_wait(cookie);
critical_exit();
}
#define tlb_tte_demap(tte, pm) \
tlb_page_demap(TD_GET_TLB((tte).tte_data), pm, \
TV_GET_VA((tte).tte_vpn));
#endif /* !_MACHINE_TLB_H_ */