v1 of this patch series here: https://lore.kernel.org/linux-mm/20220419203202.2670193-1-kent.overstreet@xxxxxxxxx/T/ Changes since v1: - Converted some, not all, seq_buf code to printbufs (thanks Christoph for pointing out seq_buf). The seq_buf code I didn't convert is arch specific code where the memory allocation context is unclear, and they're using seq_buf to do everything on the stack. I'm considering adding a mode to printbufs where we point it at an external buffer instead - it wouldn't be much code, but OTOH seq_buf isn't much code either and it seems to be somewhat tied to tracing infrastructure. Deferring a decision on what to do for now. - pr_human_readable_u64() now uses string_get_size() (thanks Matthew for pointing this one out) - added new helpers printbuf_str() for getting a guaranteed-null-terminated string, and printbuf_atomic_inc() and printbuf_atomic_dec() for marking sections where allocations must be GFP_ATOMIC. - Broke out shrinker_to_text(): this new helper could be used by new sysfs or debugfs code, for displaying information about a single shrinker (as Roman is working on) - Added new tracking, per shrinker, for # of objects requested to be freed and # actually freed. Shrinkers won't necessarily free all objects requested for perfectly legitimate reasons, but if the two numbers are wildly off then that's going to lead to memory reclaim issues - these are both also included in shrinker_to_text(). Kent Overstreet (8): lib/printbuf: New data structure for heap-allocated strings Input/joystick/analog: Convert from seq_buf -> printbuf mm/memcontrol.c: Convert to printbuf clk: tegra: bpmp: Convert to printbuf mm: Add a .to_text() method for shrinkers mm: Count requests to free & nr freed per shrinker mm: Move lib/show_mem.c to mm/ mm: Centralize & improve oom reporting in show_mem.c drivers/clk/tegra/clk-bpmp.c | 21 ++- drivers/input/joystick/analog.c | 37 +++-- include/linux/printbuf.h | 164 +++++++++++++++++++ include/linux/shrinker.h | 8 + lib/Makefile | 4 +- lib/printbuf.c | 274 ++++++++++++++++++++++++++++++++ mm/Makefile | 2 +- mm/memcontrol.c | 68 ++++---- mm/oom_kill.c | 23 --- {lib => mm}/show_mem.c | 14 ++ mm/slab.h | 6 +- mm/slab_common.c | 53 +++++- mm/vmscan.c | 88 ++++++++++ 13 files changed, 666 insertions(+), 96 deletions(-) create mode 100644 include/linux/printbuf.h create mode 100644 lib/printbuf.c rename {lib => mm}/show_mem.c (77%) -- 2.35.2