lkml.org 
[lkml]   [2022]   [Jan]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH v4 34/66] cxl: Remove vma linked list walk
From
On 12/1/21 15:30, Liam Howlett wrote:
> From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
>
> Use the VMA iterator instead. This requires a little restructuring
> of the surrounding code to hoist the mm to the caller. That turns
> cxl_prefault_one() into a trivial function, so call cxl_fault_segment()
> directly.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
> ---
> drivers/misc/cxl/fault.c | 43 +++++++++++++---------------------------
> 1 file changed, 14 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/misc/cxl/fault.c b/drivers/misc/cxl/fault.c
> index 60c829113299..504522a126b5 100644
> --- a/drivers/misc/cxl/fault.c
> +++ b/drivers/misc/cxl/fault.c
> @@ -280,22 +280,6 @@ void cxl_handle_fault(struct work_struct *fault_work)
> mmput(mm);
> }
>
> -static void cxl_prefault_one(struct cxl_context *ctx, u64 ea)
> -{
> - struct mm_struct *mm;
> -
> - mm = get_mem_context(ctx);
> - if (mm == NULL) {
> - pr_devel("cxl_prefault_one unable to get mm %i\n",
> - pid_nr(ctx->pid));
> - return;
> - }
> -
> - cxl_fault_segment(ctx, mm, ea);
> -
> - mmput(mm);
> -}
> -
> static u64 next_segment(u64 ea, u64 vsid)
> {
> if (vsid & SLB_VSID_B_1T)
> @@ -306,23 +290,16 @@ static u64 next_segment(u64 ea, u64 vsid)
> return ea + 1;
> }
>
> -static void cxl_prefault_vma(struct cxl_context *ctx)
> +static void cxl_prefault_vma(struct cxl_context *ctx, struct mm_struct *mm)
> {
> u64 ea, last_esid = 0;
> struct copro_slb slb;
> + VMA_ITERATOR(vmi, mm, 0);
> struct vm_area_struct *vma;
> int rc;
> - struct mm_struct *mm;
> -
> - mm = get_mem_context(ctx);
> - if (mm == NULL) {
> - pr_devel("cxl_prefault_vm unable to get mm %i\n",
> - pid_nr(ctx->pid));
> - return;
> - }
>
> mmap_read_lock(mm);
> - for (vma = mm->mmap; vma; vma = vma->vm_next) {
> + for_each_vma(vmi, vma) {
> for (ea = vma->vm_start; ea < vma->vm_end;
> ea = next_segment(ea, slb.vsid)) {
> rc = copro_calculate_slb(mm, ea, &slb);
> @@ -337,15 +314,21 @@ static void cxl_prefault_vma(struct cxl_context *ctx)
> }
> }
> mmap_read_unlock(mm);
> -
> - mmput(mm);
> }
>
> void cxl_prefault(struct cxl_context *ctx, u64 wed)
> {
> + struct mm_struct *mm = get_mem_context(ctx);
> +
> + if (mm == NULL) {
> + pr_devel("cxl_prefault unable to get mm %i\n",
> + pid_nr(ctx->pid));
> + return;
> + }
> +
> switch (ctx->afu->prefault_mode) {
> case CXL_PREFAULT_WED:
> - cxl_prefault_one(ctx, wed);
> + cxl_fault_segment(ctx, mm, wed);
> break;
> case CXL_PREFAULT_ALL:
> cxl_prefault_vma(ctx);

Need to pass mm here, compile tested much? :)

After fixup
Acked-by: Vlastimil Babka <vbabka@suse.cz>

> @@ -353,4 +336,6 @@ void cxl_prefault(struct cxl_context *ctx, u64 wed)
> default:
> break;
> }
> +
> + mmput(mm);
> }

\
 
 \ /
  Last update: 2022-01-18 13:38    [W:1.317 / U:0.304 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site