mbox series

[RESEND,0/2] Fix calculations in trace_balance_dirty_pages() for cgwb

Message ID 20250303100617.223677-1-yizhou.tang@shopee.com (mailing list archive)
Headers show
Series Fix calculations in trace_balance_dirty_pages() for cgwb | expand

Message

Tang Yizhou March 3, 2025, 10:06 a.m. UTC 
From: Tang Yizhou <yizhou.tang@shopee.com>

In my experiment, I found that the output of trace_balance_dirty_pages()
in the cgroup writeback scenario was strange because
trace_balance_dirty_pages() always uses global_wb_domain.dirty_limit for
related calculations instead of the dirty_limit of the corresponding
memcg's wb_domain.

The basic idea of the fix is to store the hard dirty limit value computed
in wb_position_ratio() into struct dirty_throttle_control and use it for
calculations in trace_balance_dirty_pages().

Tang Yizhou (2):
  writeback: Let trace_balance_dirty_pages() take struct dtc as
    parameter
  writeback: Fix calculations in trace_balance_dirty_pages() for cgwb

 include/linux/writeback.h        | 24 +++++++++++++++++++++
 include/trace/events/writeback.h | 33 ++++++++++++----------------
 mm/page-writeback.c              | 37 +++-----------------------------
 3 files changed, 41 insertions(+), 53 deletions(-)