Date: Mon, 10 Aug 2026 16:01:44 +0000 From: Bojan Novk=?utf-8?Q?ovi=C4=87?= <bnovkov@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: 99360212c739 - main - riscv/pmap.c: Add an Svinval-aware variant of pmap_invalidate_range Message-ID: <6a79f5e8.37105.d66886@gitrepo.freebsd.org>
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The branch main has been updated by bnovkov: URL: https://cgit.FreeBSD.org/src/commit/?id=99360212c7392f2b0b3932b40f005c71e943b65f commit 99360212c7392f2b0b3932b40f005c71e943b65f Author: Bojan Novković <bnovkov@FreeBSD.org> AuthorDate: 2026-06-16 14:55:48 +0000 Commit: Bojan Novković <bnovkov@FreeBSD.org> CommitDate: 2026-08-10 16:01:28 +0000 riscv/pmap.c: Add an Svinval-aware variant of pmap_invalidate_range This change introduces a variant of `pmap_invalidate_range` that uses the fine-grained TLB invalidation instructions introduced by the Svinval extension. These instructions allow for more efficient TLB flushing on certain implementations. Under this new scheme, `pmap_invalidate_range` was converted to an ifunc that selects the appropriate variant during boot. Event: BSDCan 2026 Reviewed by: markj, mhorne Differential Revision: https://reviews.freebsd.org/D57624 --- sys/riscv/riscv/pmap.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 71 insertions(+), 2 deletions(-) diff --git a/sys/riscv/riscv/pmap.c b/sys/riscv/riscv/pmap.c index 67123f9bfcc8..b3f03eeaab9f 100644 --- a/sys/riscv/riscv/pmap.c +++ b/sys/riscv/riscv/pmap.c @@ -159,6 +159,7 @@ #include <machine/machdep.h> #include <machine/md_var.h> +#include <machine/ifunc.h> #include <machine/pcb.h> #include <machine/sbi.h> #include <machine/thead.h> @@ -345,6 +346,7 @@ static int pmap_unuse_pt(pmap_t, vm_offset_t, pd_entry_t, struct spglist *); static int pmap_change_attr_locked(void *va, vm_size_t size, int mode); static uint64_t pmap_satp_mode(void); +static void pmap_invalidate_all(pmap_t pmap); #define pmap_clear(pte) pmap_store(pte, 0) #define pmap_clear_bits(pte, bits) atomic_clear_64(pte, bits) @@ -1077,7 +1079,7 @@ pmap_init(void) * sfence_vma() on remote CPUs. */ static void -pmap_invalidate_page(pmap_t pmap, vm_offset_t va) +pmap_invalidate_page_sbi(pmap_t pmap, vm_offset_t va) { cpuset_t mask; @@ -1092,7 +1094,7 @@ pmap_invalidate_page(pmap_t pmap, vm_offset_t va) } static void -pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) +pmap_invalidate_range_sbi(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) { cpuset_t mask; @@ -1111,6 +1113,73 @@ pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) sched_unpin(); } +#define PMAP_SVINVAL_THRESHOLD (2 * L2_SIZE) + +struct svinval_args { + vm_offset_t sva; + vm_offset_t eva; +}; + +static void +pmap_invalidate_range_svinval_cb(void *arg) +{ + struct svinval_args *args = arg; + vm_offset_t va; + + sfence_w_inval(); + for (va = args->sva; va < args->eva; va += PAGE_SIZE) + sinval_vma_page(va); + sfence_inval_ir(); +} + +static void +pmap_invalidate_range_svinval(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) +{ + struct svinval_args args; + + if (CPU_EMPTY(&pmap->pm_active)) + return; + + if (eva - sva >= PMAP_SVINVAL_THRESHOLD) { + pmap_invalidate_all(pmap); + return; + } + + sched_pin(); + args.sva = sva; + args.eva = eva; + fence(); + if (smp_started) + smp_rendezvous_cpus(pmap->pm_active, smp_no_rendezvous_barrier, + pmap_invalidate_range_svinval_cb, + smp_no_rendezvous_barrier, &args); + else + pmap_invalidate_range_svinval_cb(&args); + sched_unpin(); +} + +static void +pmap_invalidate_page_svinval(pmap_t pmap, vm_offset_t va) +{ + pmap_invalidate_range_svinval(pmap, va, va + PAGE_SIZE); +} + +DEFINE_IFUNC(, void, pmap_invalidate_range, + (pmap_t pmap, vm_offset_t sva, vm_offset_t eva)) +{ + if (has_svinval) + return (pmap_invalidate_range_svinval); + return (pmap_invalidate_range_sbi); +} + +DEFINE_IFUNC(, void, pmap_invalidate_page, + (pmap_t pmap, vm_offset_t va)) +{ + if (has_svinval) + return (pmap_invalidate_page_svinval); + return (pmap_invalidate_page_sbi); +} + static void pmap_invalidate_all(pmap_t pmap) {home | help
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