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amd64: Reduce the amount of cpuset copying done for TLB shootdowns

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We use pmap_invalidate_cpu_mask() to get the set of active CPUs.  This
(32-byte) set is copied by value through multiple frames until we get to
smp_targeted_tlb_shootdown(), where it is copied yet again.

Avoid this copying by having smp_targeted_tlb_shootdown() make a local
copy of the active CPUs for the pmap, and drop the cpuset parameter,
simplifying callers.  Also leverage the use of the non-destructive
CPU_FOREACH_ISSET to avoid unneeded copying within
smp_targeted_tlb_shootdown().

Reviewed by:	alc, kib
Tested by:	pho
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D32792
This commit is contained in:
Mark Johnston 2021-11-15 12:52:03 -05:00
parent 71e6e9da22
commit ab12e8db29
4 changed files with 40 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

39
sys/amd64/amd64/mp_machdep.c
View File

@ -613,10 +613,10 @@ invl_scoreboard_slot(u_int cpu)
* completion.
*/
static void
smp_targeted_tlb_shootdown(cpuset_t mask, pmap_t pmap, vm_offset_t addr1,
vm_offset_t addr2, smp_invl_cb_t curcpu_cb, enum invl_op_codes op)
smp_targeted_tlb_shootdown(pmap_t pmap, vm_offset_t addr1, vm_offset_t addr2,
smp_invl_cb_t curcpu_cb, enum invl_op_codes op)
{
cpuset_t other_cpus;
cpuset_t mask;
uint32_t generation, *p_cpudone;
int cpu;
bool is_all;
@ -631,10 +631,12 @@ smp_targeted_tlb_shootdown(cpuset_t mask, pmap_t pmap, vm_offset_t addr1,
KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
/*
* Check for other cpus. Return if none.
* Make a stable copy of the set of CPUs on which the pmap is active.
* See if we have to interrupt other CPUs.
*/
is_all = !CPU_CMP(&mask, &all_cpus);
CPU_CLR(PCPU_GET(cpuid), &mask);
CPU_COPY(pmap_invalidate_cpu_mask(pmap), &mask);
is_all = CPU_CMP(&mask, &all_cpus) == 0;
CPU_CLR(curcpu, &mask);
if (CPU_EMPTY(&mask))
goto local_cb;
@ -663,7 +665,7 @@ smp_targeted_tlb_shootdown(cpuset_t mask, pmap_t pmap, vm_offset_t addr1,
CPU_FOREACH_ISSET(cpu, &mask) {
KASSERT(*invl_scoreboard_slot(cpu) != 0,
("IPI scoreboard is zero, initiator %d target %d",
PCPU_GET(cpuid), cpu));
curcpu, cpu));
*invl_scoreboard_slot(cpu) = 0;
}
@ -674,14 +676,11 @@ smp_targeted_tlb_shootdown(cpuset_t mask, pmap_t pmap, vm_offset_t addr1,
*/
if (is_all) {
ipi_all_but_self(IPI_INVLOP);
other_cpus = all_cpus;
CPU_CLR(PCPU_GET(cpuid), &other_cpus);
} else {
other_cpus = mask;
ipi_selected(mask, IPI_INVLOP);
}
curcpu_cb(pmap, addr1, addr2);
CPU_FOREACH_ISSET(cpu, &other_cpus) {
CPU_FOREACH_ISSET(cpu, &mask) {
p_cpudone = invl_scoreboard_slot(cpu);
while (atomic_load_int(p_cpudone) != generation)
ia32_pause();
@ -705,29 +704,28 @@ smp_targeted_tlb_shootdown(cpuset_t mask, pmap_t pmap, vm_offset_t addr1,
}
void
smp_masked_invltlb(cpuset_t mask, pmap_t pmap, smp_invl_cb_t curcpu_cb)
smp_masked_invltlb(pmap_t pmap, smp_invl_cb_t curcpu_cb)
{
smp_targeted_tlb_shootdown(mask, pmap, 0, 0, curcpu_cb, invl_op_tlb);
smp_targeted_tlb_shootdown(pmap, 0, 0, curcpu_cb, invl_op_tlb);
#ifdef COUNT_XINVLTLB_HITS
ipi_global++;
#endif
}
void
smp_masked_invlpg(cpuset_t mask, vm_offset_t addr, pmap_t pmap,
smp_invl_cb_t curcpu_cb)
smp_masked_invlpg(vm_offset_t addr, pmap_t pmap, smp_invl_cb_t curcpu_cb)
{
smp_targeted_tlb_shootdown(mask, pmap, addr, 0, curcpu_cb, invl_op_pg);
smp_targeted_tlb_shootdown(pmap, addr, 0, curcpu_cb, invl_op_pg);
#ifdef COUNT_XINVLTLB_HITS
ipi_page++;
#endif
}
void
smp_masked_invlpg_range(cpuset_t mask, vm_offset_t addr1, vm_offset_t addr2,
pmap_t pmap, smp_invl_cb_t curcpu_cb)
smp_masked_invlpg_range(vm_offset_t addr1, vm_offset_t addr2, pmap_t pmap,
smp_invl_cb_t curcpu_cb)
{
smp_targeted_tlb_shootdown(mask, pmap, addr1, addr2, curcpu_cb,
smp_targeted_tlb_shootdown(pmap, addr1, addr2, curcpu_cb,
invl_op_pgrng);
#ifdef COUNT_XINVLTLB_HITS
ipi_range++;
@ -738,8 +736,7 @@ smp_masked_invlpg_range(cpuset_t mask, vm_offset_t addr1, vm_offset_t addr2,
void
smp_cache_flush(smp_invl_cb_t curcpu_cb)
{
smp_targeted_tlb_shootdown(all_cpus, NULL, 0, 0, curcpu_cb,
INVL_OP_CACHE);
smp_targeted_tlb_shootdown(kernel_pmap, 0, 0, curcpu_cb, INVL_OP_CACHE);
}
/*

8
sys/amd64/amd64/pmap.c
View File

@ -3146,8 +3146,7 @@ pmap_invalidate_page(pmap_t pmap, vm_offset_t va)
("pmap_invalidate_page: invalid type %d", pmap->pm_type));
pmap_invalidate_preipi(pmap);
smp_masked_invlpg(pmap_invalidate_cpu_mask(pmap), va, pmap,
pmap_invalidate_page_curcpu_cb);
smp_masked_invlpg(va, pmap, pmap_invalidate_page_curcpu_cb);
}
/* 4k PTEs -- Chosen to exceed the total size of Broadwell L2 TLB */
@ -3245,7 +3244,7 @@ pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
("pmap_invalidate_range: invalid type %d", pmap->pm_type));
pmap_invalidate_preipi(pmap);
smp_masked_invlpg_range(pmap_invalidate_cpu_mask(pmap), sva, eva, pmap,
smp_masked_invlpg_range(sva, eva, pmap,
pmap_invalidate_range_curcpu_cb);
}
@ -3331,8 +3330,7 @@ pmap_invalidate_all(pmap_t pmap)
("pmap_invalidate_all: invalid type %d", pmap->pm_type));
pmap_invalidate_preipi(pmap);
smp_masked_invltlb(pmap_invalidate_cpu_mask(pmap), pmap,
pmap_invalidate_all_curcpu_cb);
smp_masked_invltlb(pmap, pmap_invalidate_all_curcpu_cb);
}
static void

9
sys/amd64/include/pmap.h
View File

@ -532,10 +532,15 @@ vm_page_t pmap_page_alloc_below_4g(bool zeroed);
void pmap_san_enter(vm_offset_t);
#endif
static __inline cpuset_t
/*
* Returns a pointer to a set of CPUs on which the pmap is currently active.
* Note that the set can be modified without any mutual exclusion, so a copy
* must be made if a stable value is required.
*/
static __inline volatile cpuset_t *
pmap_invalidate_cpu_mask(pmap_t pmap)
{
return (pmap->pm_active);
return (&pmap->pm_active);
}
#endif /* _KERNEL */

15
sys/x86/include/x86_smp.h
View File

@ -107,14 +107,23 @@ void ipi_swi_handler(struct trapframe frame);
void ipi_selected(cpuset_t cpus, u_int ipi);
void ipi_self_from_nmi(u_int vector);
void set_interrupt_apic_ids(void);
void mem_range_AP_init(void);
void topo_probe(void);
/* functions in mp_machdep.c */
void smp_cache_flush(smp_invl_cb_t curcpu_cb);
#ifdef __i386__
void smp_masked_invlpg(cpuset_t mask, vm_offset_t addr, struct pmap *pmap,
smp_invl_cb_t curcpu_cb);
void smp_masked_invlpg_range(cpuset_t mask, vm_offset_t startva,
vm_offset_t endva, struct pmap *pmap, smp_invl_cb_t curcpu_cb);
void smp_masked_invltlb(cpuset_t mask, struct pmap *pmap,
smp_invl_cb_t curcpu_cb);
void mem_range_AP_init(void);
void topo_probe(void);
#else
void smp_masked_invlpg(vm_offset_t addr, struct pmap *pmap,
smp_invl_cb_t curcpu_cb);
void smp_masked_invlpg_range(vm_offset_t startva, vm_offset_t endva,
struct pmap *pmap, smp_invl_cb_t curcpu_cb);
void smp_masked_invltlb(struct pmap *pmap, smp_invl_cb_t curcpu_cb);
#endif
#endif