git: 9d1f3ce79d85 - main - pmap: Degrade pmap_page_set_attr*() into a no-op on same attribute
- Go to: [ bottom of page ] [ top of archives ] [ this month ]
Date: Sun, 13 Jul 2025 07:27:33 UTC
The branch main has been updated by olce:
URL: https://cgit.FreeBSD.org/src/commit/?id=9d1f3ce79d85855399663e3977766ec46f28cadd
commit 9d1f3ce79d85855399663e3977766ec46f28cadd
Author: Olivier Certner <olce@FreeBSD.org>
AuthorDate: 2025-07-08 16:17:30 +0000
Commit: Olivier Certner <olce@FreeBSD.org>
CommitDate: 2025-07-13 07:13:25 +0000
pmap: Degrade pmap_page_set_attr*() into a no-op on same attribute
For 32-bit arm, move the no-op test that was already in place at start
of the function so that it stays first even if the '#if 0' block around
the call to sf_buf_invalidate_cache() is uncommented at some point (if
ever).
Reviewed by: jeffpc_josefsipek.net, kib
MFC after: 10 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D51253
---
sys/amd64/amd64/pmap.c | 5 +++++
sys/arm/arm/pmap-v6.c | 32 +++++++++++++++-----------------
sys/arm64/arm64/pmap.c | 2 ++
sys/i386/i386/pmap.c | 2 ++
sys/powerpc/aim/mmu_oea.c | 3 +++
sys/powerpc/aim/mmu_oea64.c | 3 +++
sys/powerpc/aim/mmu_radix.c | 4 ++++
sys/riscv/riscv/pmap.c | 2 ++
8 files changed, 36 insertions(+), 17 deletions(-)
diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
index 9c985df13ddf..fd02d1ad6690 100644
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -9649,6 +9649,8 @@ pmap_demote_pdpe(pmap_t pmap, pdp_entry_t *pdpe, vm_offset_t va, vm_page_t m)
void
pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
{
+ if (m->md.pat_mode == ma)
+ return;
m->md.pat_mode = ma;
@@ -9668,6 +9670,9 @@ pmap_page_set_memattr_noflush(vm_page_t m, vm_memattr_t ma)
{
int error;
+ if (m->md.pat_mode == ma)
+ return;
+
m->md.pat_mode = ma;
if ((m->flags & PG_FICTITIOUS) != 0)
diff --git a/sys/arm/arm/pmap-v6.c b/sys/arm/arm/pmap-v6.c
index 92eb0589f80b..78883296c5b7 100644
--- a/sys/arm/arm/pmap-v6.c
+++ b/sys/arm/arm/pmap-v6.c
@@ -5767,7 +5767,7 @@ pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
CTR5(KTR_PMAP, "%s: page %p - 0x%08X oma: %d, ma: %d", __func__, m,
VM_PAGE_TO_PHYS(m), oma, ma);
- if ((m->flags & PG_FICTITIOUS) != 0)
+ if (ma == oma || (m->flags & PG_FICTITIOUS) != 0)
return;
#if 0
/*
@@ -5784,22 +5784,20 @@ pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
* If page is not mapped by sf buffer, map the page
* transient and do invalidation.
*/
- if (ma != oma) {
- pa = VM_PAGE_TO_PHYS(m);
- sched_pin();
- pc = get_pcpu();
- cmap2_pte2p = pc->pc_cmap2_pte2p;
- mtx_lock(&pc->pc_cmap_lock);
- if (pte2_load(cmap2_pte2p) != 0)
- panic("%s: CMAP2 busy", __func__);
- pte2_store(cmap2_pte2p, PTE2_KERN_NG(pa, PTE2_AP_KRW,
- vm_memattr_to_pte2(ma)));
- dcache_wbinv_poc((vm_offset_t)pc->pc_cmap2_addr, pa, PAGE_SIZE);
- pte2_clear(cmap2_pte2p);
- tlb_flush((vm_offset_t)pc->pc_cmap2_addr);
- sched_unpin();
- mtx_unlock(&pc->pc_cmap_lock);
- }
+ pa = VM_PAGE_TO_PHYS(m);
+ sched_pin();
+ pc = get_pcpu();
+ cmap2_pte2p = pc->pc_cmap2_pte2p;
+ mtx_lock(&pc->pc_cmap_lock);
+ if (pte2_load(cmap2_pte2p) != 0)
+ panic("%s: CMAP2 busy", __func__);
+ pte2_store(cmap2_pte2p, PTE2_KERN_NG(pa, PTE2_AP_KRW,
+ vm_memattr_to_pte2(ma)));
+ dcache_wbinv_poc((vm_offset_t)pc->pc_cmap2_addr, pa, PAGE_SIZE);
+ pte2_clear(cmap2_pte2p);
+ tlb_flush((vm_offset_t)pc->pc_cmap2_addr);
+ sched_unpin();
+ mtx_unlock(&pc->pc_cmap_lock);
}
/*
diff --git a/sys/arm64/arm64/pmap.c b/sys/arm64/arm64/pmap.c
index d2e56a270f54..dbd1ed7b316b 100644
--- a/sys/arm64/arm64/pmap.c
+++ b/sys/arm64/arm64/pmap.c
@@ -8045,6 +8045,8 @@ pmap_unmapbios(void *p, vm_size_t size)
void
pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
{
+ if (m->md.pv_memattr == ma)
+ return;
m->md.pv_memattr = ma;
diff --git a/sys/i386/i386/pmap.c b/sys/i386/i386/pmap.c
index 465b4d0f365b..5065b7e61ee8 100644
--- a/sys/i386/i386/pmap.c
+++ b/sys/i386/i386/pmap.c
@@ -5617,6 +5617,8 @@ __CONCAT(PMTYPE, unmapdev)(void *p, vm_size_t size)
static void
__CONCAT(PMTYPE, page_set_memattr)(vm_page_t m, vm_memattr_t ma)
{
+ if (m->md.pat_mode == ma)
+ return;
m->md.pat_mode = ma;
if ((m->flags & PG_FICTITIOUS) != 0)
diff --git a/sys/powerpc/aim/mmu_oea.c b/sys/powerpc/aim/mmu_oea.c
index 7746b668265d..ae17b3289593 100644
--- a/sys/powerpc/aim/mmu_oea.c
+++ b/sys/powerpc/aim/mmu_oea.c
@@ -1469,6 +1469,9 @@ moea_page_set_memattr(vm_page_t m, vm_memattr_t ma)
pmap_t pmap;
u_int lo;
+ if (m->md.mdpg_cache_attrs == ma)
+ return;
+
if ((m->oflags & VPO_UNMANAGED) != 0) {
m->md.mdpg_cache_attrs = ma;
return;
diff --git a/sys/powerpc/aim/mmu_oea64.c b/sys/powerpc/aim/mmu_oea64.c
index 79cea408bb5f..796b1719b8ba 100644
--- a/sys/powerpc/aim/mmu_oea64.c
+++ b/sys/powerpc/aim/mmu_oea64.c
@@ -2134,6 +2134,9 @@ moea64_page_set_memattr(vm_page_t m, vm_memattr_t ma)
CTR3(KTR_PMAP, "%s: pa=%#jx, ma=%#x",
__func__, (uintmax_t)VM_PAGE_TO_PHYS(m), ma);
+ if (m->md.mdpg_cache_attrs == ma)
+ return;
+
if ((m->oflags & VPO_UNMANAGED) != 0) {
m->md.mdpg_cache_attrs = ma;
return;
diff --git a/sys/powerpc/aim/mmu_radix.c b/sys/powerpc/aim/mmu_radix.c
index 45f7bef8bcc9..a12142fc2d7b 100644
--- a/sys/powerpc/aim/mmu_radix.c
+++ b/sys/powerpc/aim/mmu_radix.c
@@ -5937,6 +5937,10 @@ mmu_radix_page_set_memattr(vm_page_t m, vm_memattr_t ma)
{
CTR3(KTR_PMAP, "%s(%p, %#x)", __func__, m, ma);
+
+ if (m->md.mdpg_cache_attrs == ma)
+ return;
+
m->md.mdpg_cache_attrs = ma;
/*
diff --git a/sys/riscv/riscv/pmap.c b/sys/riscv/riscv/pmap.c
index 5d15bd671285..26efaecc64d1 100644
--- a/sys/riscv/riscv/pmap.c
+++ b/sys/riscv/riscv/pmap.c
@@ -4838,6 +4838,8 @@ pmap_unmapbios(void *p, vm_size_t size)
void
pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
{
+ if (m->md.pv_memattr == ma)
+ return;
m->md.pv_memattr = ma;