diff options
| author | Suren Baghdasaryan <surenb@google.com> | 2026-01-16 10:44:23 -0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-01-20 09:34:26 -0800 |
| commit | cb7d761bf5d4b1600564efdd42653b821eb2ec8e (patch) | |
| tree | 61389bfeea48b3bf0d949203f9b5001bc35ef357 | |
| parent | 35e247032606f06c2f19d90a6562bc315206b7a7 (diff) | |
Docs/mm/allocation-profiling: describe sysctrl limitations in debug mode
When CONFIG_MEM_ALLOC_PROFILING_DEBUG=y, /proc/sys/vm/mem_profiling is
read-only to avoid debug warnings in a scenario when an allocation is
made while profiling is disabled (allocation does not get an allocation
tag), then profiling gets enabled and allocation gets freed (warning due
to the allocation missing allocation tag).
Link: https://lkml.kernel.org/r/20260116184423.2708363-1-surenb@google.com
Fixes: ebdf9ad4ca98 ("memprofiling: documentation")
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ran Xiaokai <ran.xiaokai@zte.com.cn>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | Documentation/admin-guide/sysctl/vm.rst | 4 | ||||
| -rw-r--r-- | Documentation/mm/allocation-profiling.rst | 10 |
2 files changed, 14 insertions, 0 deletions
diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst index 4d71211fdad8..245bf6394935 100644 --- a/Documentation/admin-guide/sysctl/vm.rst +++ b/Documentation/admin-guide/sysctl/vm.rst @@ -494,6 +494,10 @@ memory allocations. The default value depends on CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT. +When CONFIG_MEM_ALLOC_PROFILING_DEBUG=y, this control is read-only to avoid +warnings produced by allocations made while profiling is disabled and freed +when it's enabled. + memory_failure_early_kill ========================= diff --git a/Documentation/mm/allocation-profiling.rst b/Documentation/mm/allocation-profiling.rst index 316311240e6a..5389d241176a 100644 --- a/Documentation/mm/allocation-profiling.rst +++ b/Documentation/mm/allocation-profiling.rst @@ -33,6 +33,16 @@ Boot parameter: sysctl: /proc/sys/vm/mem_profiling + 1: Enable memory profiling. + + 0: Disable memory profiling. + + The default value depends on CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT. + + When CONFIG_MEM_ALLOC_PROFILING_DEBUG=y, this control is read-only to avoid + warnings produced by allocations made while profiling is disabled and freed + when it's enabled. + Runtime info: /proc/allocinfo |