22e71691fd
I can observe that RHEL7 environment stalls with 100% CPU usage when a certain type of memory pressure is given. While the shrinker functions are called by shrink_slab() before the OOM killer is triggered, the stall lasts for many minutes. One of reasons of this stall is that ttm_dma_pool_shrink_count()/ttm_dma_pool_shrink_scan() are called and are blocked at mutex_lock(&_manager->lock). GFP_KERNEL allocation with _manager->lock held causes someone (including kswapd) to deadlock when these functions are called due to memory pressure. This patch changes "mutex_lock();" to "if (!mutex_trylock()) return ...;" in order to avoid deadlock. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: stable <stable@kernel.org> [3.3+] Signed-off-by: Dave Airlie <airlied@redhat.com> |
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| drm | ||
| host1x | ||
| ipu-v3 | ||
| vga | ||
| Makefile | ||