mm/page_alloc: avoid second trylock of zone->lock

spin_trylock followed by spin_lock will cause extra write cache access. 
If the lock is contended it may cause unnecessary cache line bouncing and
will execute redundant irq restore/save pair.  Therefore, check
alloc/fpi_flags first and use spin_trylock or spin_lock.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 97769a53f117 ("mm, bpf: Introduce try_alloc_pages() for opportunistic page allocation")
Signed-off-by: Alexei Starovoitov <[email protected]>
Suggested-by: Linus Torvalds <[email protected]>
Reviewed-by: Sebastian Andrzej Siewior <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Reviewed-by: Harry Yoo <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: Daniel Borkman <[email protected]>
Cc: Martin KaFai Lau <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Steven Rostedt <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions