linux

iv/linux

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Dexuan Cui a1255ccab8 swiotlb: do not set total_used to 0 in swiotlb_create_debugfs_files()

Sometimes the readout of /sys/kernel/debug/swiotlb/io_tlb_used and
io_tlb_used_hiwater can be a huge number (e.g. 18446744073709551615),
which is actually a negative number if we use "%ld" to print the number.

When swiotlb_create_default_debugfs() is running from late_initcall,
mem->total_used may already be non-zero, because the storage driver
may have already started to perform I/O operations: if the storage
driver is built-in, its probe() callback is called before late_initcall.

swiotlb_create_debugfs_files() should not blindly set mem->total_used
and mem->used_hiwater to 0; actually it doesn't have to initialize the
fields at all, because the fields, as part of the global struct
io_tlb_default_mem, have been implicitly initialized to zero.

Also don't explicitly set mem->transient_nslabs to 0.

Fixes: 8b0977ecc8b3 ("swiotlb: track and report io_tlb_used high water marks in debugfs")
Fixes: 02e765697038 ("swiotlb: add debugfs to track swiotlb transient pool usage")
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by: Petr Tesarik <petr.tesarik1@huawei-partners.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

2024-04-02 17:08:09 +02:00

coherent.c

dma-mapping: clear dev->dma_mem to NULL after freeing it

2023-12-15 12:32:45 +01:00

contiguous.c

mm/cma: drop CONFIG_CMA_DEBUG

2024-02-22 10:24:53 -08:00

debug.c

dma-mapping fixes for Linux 6.8

2024-01-18 16:49:34 -08:00

debug.h

dma-debug: teach add_dma_entry() about DMA_ATTR_SKIP_CPU_SYNC