Re: [PATCH v6 1/2] dma-contiguous: provide the ability to reserve per-numa CMA
From: Randy Dunlap <hidden>
Date: 2020-08-21 02:50:17
Also in:
linux-iommu, lkml
On 8/20/20 7:26 PM, Barry Song wrote:
quoted hunk ↗ jump to hunk
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Will Deacon <will@kernel.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Ganapatrao Kulkarni <redacted> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Nicolas Saenz Julienne <redacted> Cc: Steve Capper <redacted> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mike Rapoport <redacted> Signed-off-by: Barry Song <redacted> --- v6: rebase on top of 5.9-rc1; doc cleanup .../admin-guide/kernel-parameters.txt | 9 ++ include/linux/dma-contiguous.h | 6 ++ kernel/dma/Kconfig | 10 ++ kernel/dma/contiguous.c | 100 ++++++++++++++++-- 4 files changed, 115 insertions(+), 10 deletions(-)diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index bdc1f33fd3d1..3f33b89aeab5 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt@@ -599,6 +599,15 @@ altogether. For more information, see include/linux/dma-contiguous.h + pernuma_cma=nn[MG]
memparse() allows any one of these suffixes: K, M, G, T, P, E and nothing in the option parsing function cares what suffix is used...
+ [ARM64,KNL]
+ Sets the size of kernel per-numa memory area for
+ contiguous memory allocations. A value of 0 disables
+ per-numa CMA altogether. DMA users on node nid will
+ first try to allocate buffer from the pernuma area
+ which is located in node nid, if the allocation fails,
+ they will fallback to the global default memory area.
+
cmo_free_hint= [PPC] Format: { yes | no }
Specify whether pages are marked as being inactive
when they are freed. This is used in CMO environmentsquoted hunk ↗ jump to hunk
diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index cff7e60968b9..89b95f10e56d 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c@@ -69,6 +69,19 @@ static int __init early_cma(char *p) } early_param("cma", early_cma); +#ifdef CONFIG_DMA_PERNUMA_CMA + +static struct cma *dma_contiguous_pernuma_area[MAX_NUMNODES]; +static phys_addr_t pernuma_size_bytes __initdata;
why phys_addr_t? couldn't it just be unsigned long long? OK, so cma_declare_contiguous_nid() uses phys_addr_t. Fine.
quoted hunk ↗ jump to hunk
+ +static int __init early_pernuma_cma(char *p) +{ + pernuma_size_bytes = memparse(p, &p); + return 0; +} +early_param("pernuma_cma", early_pernuma_cma); +#endif + #ifdef CONFIG_CMA_SIZE_PERCENTAGE static phys_addr_t __init __maybe_unused cma_early_percent_memory(void)@@ -96,6 +109,34 @@ static inline __maybe_unused phys_addr_t cma_early_percent_memory(void) #endif +#ifdef CONFIG_DMA_PERNUMA_CMA +void __init dma_pernuma_cma_reserve(void) +{ + int nid; + + if (!pernuma_size_bytes) + return; + + for_each_node_state(nid, N_ONLINE) { + int ret; + char name[20]; + struct cma **cma = &dma_contiguous_pernuma_area[nid]; + + snprintf(name, sizeof(name), "pernuma%d", nid); + ret = cma_declare_contiguous_nid(0, pernuma_size_bytes, 0, 0, + 0, false, name, cma, nid); + if (ret) { + pr_warn("%s: reservation failed: err %d, node %d", __func__, + ret, nid); + continue; + } + + pr_debug("%s: reserved %llu MiB on node %d\n", __func__, + (unsigned long long)pernuma_size_bytes / SZ_1M, nid);
Conversely, if you want to leave pernuma_size_bytes as phys_addr_t, you should use %pa (or %pap) to print it.
+ } +} +#endif
-- ~Randy _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel