mirror of
https://github.com/torvalds/linux.git
synced 2026-10-07 05:31:08 -04:00
Sergei Trofimovich
8e9b16c476
Before the change page_owner recursion was detected via fetching backtrace and inspecting it for current instruction pointer. It has a few problems: - it is slightly slow as it requires extra backtrace and a linear stack scan of the result - it is too late to check if backtrace fetching required memory allocation itself (ia64's unwinder requires it). To simplify recursion tracking let's use page_owner recursion flag in 'struct task_struct'. The change make page_owner=on work on ia64 by avoiding infinite recursion in: kmalloc() -> __set_page_owner() -> save_stack() -> unwind() [ia64-specific] -> build_script() -> kmalloc() -> __set_page_owner() [we short-circuit here] -> save_stack() -> unwind() [recursion] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Sergei Trofimovich <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Juri Lelli <[email protected]> Cc: Vincent Guittot <[email protected]> Cc: Dietmar Eggemann <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Ben Segall <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Daniel Bristot de Oliveira <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>