The quilt patch titled
Subject: mm/page_alloc: add trace event for per-zone watermark setup
has been removed from the -mm tree. Its filename was
mm-page_alloc-add-trace-event-for-per-zone-watermark-setup.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Martin Liu <liumartin@xxxxxxxxxx>
Subject: mm/page_alloc: add trace event for per-zone watermark setup
Date: Sat, 8 Mar 2025 03:46:00 +0000
Patch series "Add tracepoints for lowmem reserves, watermarks and
totalreserve_pages", v2.
This patchset introduces tracepoints to track changes in the lowmem
reserves, watermarks and totalreserve_pages. This helps to track
the exact timing of such changes and understand their relation to
reclaim activities.
The tracepoints added are:
mm_setup_per_zone_lowmem_reserve
mm_setup_per_zone_wmarks
mm_calculate_totalreserve_pagesi
This patch (of 3):
This commit introduces the `mm_setup_per_zone_wmarks` trace event,
which provides detailed insights into the kernel's per-zone watermark
configuration, offering precise timing and the ability to correlate
watermark changes with specific kernel events.
While `/proc/zoneinfo` provides some information about zone watermarks,
this trace event offers:
1. The ability to link watermark changes to specific kernel events and
logic.
2. The ability to capture rapid or short-lived changes in watermarks
that may be missed by user-space polling
3. Diagnosing unexpected kswapd activity or excessive direct reclaim
triggered by rapidly changing watermarks.
Link: https://lkml.kernel.org/r/20250308034606.2036033-1-liumartin@xxxxxxxxxx
Link: https://lkml.kernel.org/r/20250308034606.2036033-2-liumartin@xxxxxxxxxx
Signed-off-by: Martin Liu <liumartin@xxxxxxxxxx>
Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Martin Liu <liumartin@xxxxxxxxxx>
Cc: "Masami Hiramatsu (Google)" <mhiramat@xxxxxxxxxx>
Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/trace/events/kmem.h | 33 +++++++++++++++++++++++++++++++++
mm/page_alloc.c | 1 +
2 files changed, 34 insertions(+)
--- a/include/trace/events/kmem.h~mm-page_alloc-add-trace-event-for-per-zone-watermark-setup
+++ a/include/trace/events/kmem.h
@@ -342,6 +342,39 @@ TRACE_EVENT(mm_alloc_contig_migrate_rang
__entry->nr_mapped)
);
+TRACE_EVENT(mm_setup_per_zone_wmarks,
+
+ TP_PROTO(struct zone *zone),
+
+ TP_ARGS(zone),
+
+ TP_STRUCT__entry(
+ __field(int, node_id)
+ __string(name, zone->name)
+ __field(unsigned long, watermark_min)
+ __field(unsigned long, watermark_low)
+ __field(unsigned long, watermark_high)
+ __field(unsigned long, watermark_promo)
+ ),
+
+ TP_fast_assign(
+ __entry->node_id = zone->zone_pgdat->node_id;
+ __assign_str(name);
+ __entry->watermark_min = zone->_watermark[WMARK_MIN];
+ __entry->watermark_low = zone->_watermark[WMARK_LOW];
+ __entry->watermark_high = zone->_watermark[WMARK_HIGH];
+ __entry->watermark_promo = zone->_watermark[WMARK_PROMO];
+ ),
+
+ TP_printk("node_id=%d zone name=%s watermark min=%lu low=%lu high=%lu promo=%lu",
+ __entry->node_id,
+ __get_str(name),
+ __entry->watermark_min,
+ __entry->watermark_low,
+ __entry->watermark_high,
+ __entry->watermark_promo)
+);
+
/*
* Required for uniquely and securely identifying mm in rss_stat tracepoint.
*/
--- a/mm/page_alloc.c~mm-page_alloc-add-trace-event-for-per-zone-watermark-setup
+++ a/mm/page_alloc.c
@@ -6006,6 +6006,7 @@ static void __setup_per_zone_wmarks(void
zone->_watermark[WMARK_LOW] = min_wmark_pages(zone) + tmp;
zone->_watermark[WMARK_HIGH] = low_wmark_pages(zone) + tmp;
zone->_watermark[WMARK_PROMO] = high_wmark_pages(zone) + tmp;
+ trace_mm_setup_per_zone_wmarks(zone);
spin_unlock_irqrestore(&zone->lock, flags);
}
_
Patches currently in -mm which might be from liumartin@xxxxxxxxxx are
