diff options
| author | Rik van Riel <riel@surriel.com> | 2025-02-26 06:00:36 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2025-03-19 13:08:07 +0300 |
| commit | 4a02ed8e1cc33acd04d8f5b89751d3bbb6be35d8 (patch) | |
| tree | 010862aab3c82d21c77e075a5ac29f05857f2a04 | |
| parent | 631ca8909fd5c62b9fda9edda93924311a78a9c4 (diff) | |
| download | linux-4a02ed8e1cc33acd04d8f5b89751d3bbb6be35d8.tar.xz | |
x86/mm: Consolidate full flush threshold decision
Reduce code duplication by consolidating the decision point for whether to do
individual invalidations or a full flush inside get_flush_tlb_info().
Suggested-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Link: https://lore.kernel.org/r/20250226030129.530345-2-riel@surriel.com
| -rw-r--r-- | arch/x86/mm/tlb.c | 41 |
1 files changed, 19 insertions, 22 deletions
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index ffc25b348041..dbcb5c968ff9 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -1000,6 +1000,15 @@ static struct flush_tlb_info *get_flush_tlb_info(struct mm_struct *mm, BUG_ON(this_cpu_inc_return(flush_tlb_info_idx) != 1); #endif + /* + * If the number of flushes is so large that a full flush + * would be faster, do a full flush. + */ + if ((end - start) >> stride_shift > tlb_single_page_flush_ceiling) { + start = 0; + end = TLB_FLUSH_ALL; + } + info->start = start; info->end = end; info->mm = mm; @@ -1026,17 +1035,8 @@ void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, bool freed_tables) { struct flush_tlb_info *info; + int cpu = get_cpu(); u64 new_tlb_gen; - int cpu; - - cpu = get_cpu(); - - /* Should we flush just the requested range? */ - if ((end == TLB_FLUSH_ALL) || - ((end - start) >> stride_shift) > tlb_single_page_flush_ceiling) { - start = 0; - end = TLB_FLUSH_ALL; - } /* This is also a barrier that synchronizes with switch_mm(). */ new_tlb_gen = inc_mm_tlb_gen(mm); @@ -1089,22 +1089,19 @@ static void do_kernel_range_flush(void *info) void flush_tlb_kernel_range(unsigned long start, unsigned long end) { - /* Balance as user space task's flush, a bit conservative */ - if (end == TLB_FLUSH_ALL || - (end - start) > tlb_single_page_flush_ceiling << PAGE_SHIFT) { - on_each_cpu(do_flush_tlb_all, NULL, 1); - } else { - struct flush_tlb_info *info; + struct flush_tlb_info *info; + + guard(preempt)(); - preempt_disable(); - info = get_flush_tlb_info(NULL, start, end, 0, false, - TLB_GENERATION_INVALID); + info = get_flush_tlb_info(NULL, start, end, PAGE_SHIFT, false, + TLB_GENERATION_INVALID); + if (info->end == TLB_FLUSH_ALL) + on_each_cpu(do_flush_tlb_all, NULL, 1); + else on_each_cpu(do_kernel_range_flush, info, 1); - put_flush_tlb_info(); - preempt_enable(); - } + put_flush_tlb_info(); } /* |