| Message ID | 20231110140721.114235-1-alexghiti@rivosinc.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | riscv: Enable percpu page first chunk allocator | expand |
Hi Tejun, On 10/11/2023 15:07, Alexandre Ghiti wrote: > While working with pcpu variables, I noticed that riscv did not support > first chunk allocation in the vmalloc area which may be needed as a fallback > in case of a sparse NUMA configuration. > > patch 1 starts by introducing a new function flush_cache_vmap_early() which > is needed since a new vmalloc mapping is established and directly accessed: > on riscv, this would likely fail in case of a reordered access or if the > uarch caches invalid entries in TLB. > > patch 2 simply enables the page percpu first chunk allocator in riscv. > > Alexandre Ghiti (2): > mm: Introduce flush_cache_vmap_early() and its riscv implementation > riscv: Enable pcpu page first chunk allocator > > arch/riscv/Kconfig | 2 ++ > arch/riscv/include/asm/cacheflush.h | 3 ++- > arch/riscv/include/asm/tlbflush.h | 2 ++ > arch/riscv/mm/kasan_init.c | 8 ++++++++ > arch/riscv/mm/tlbflush.c | 5 +++++ > include/asm-generic/cacheflush.h | 6 ++++++ > mm/percpu.c | 8 +------- > 7 files changed, 26 insertions(+), 8 deletions(-) > Any feedback regarding this? Thanks, Alex
On Wed, Dec 06, 2023 at 11:08:20AM +0100, Alexandre Ghiti wrote: > Hi Tejun, > > On 10/11/2023 15:07, Alexandre Ghiti wrote: > > While working with pcpu variables, I noticed that riscv did not support > > first chunk allocation in the vmalloc area which may be needed as a fallback > > in case of a sparse NUMA configuration. > > > > patch 1 starts by introducing a new function flush_cache_vmap_early() which > > is needed since a new vmalloc mapping is established and directly accessed: > > on riscv, this would likely fail in case of a reordered access or if the > > uarch caches invalid entries in TLB. > > > > patch 2 simply enables the page percpu first chunk allocator in riscv. > > > > Alexandre Ghiti (2): > > mm: Introduce flush_cache_vmap_early() and its riscv implementation > > riscv: Enable pcpu page first chunk allocator > > > > arch/riscv/Kconfig | 2 ++ > > arch/riscv/include/asm/cacheflush.h | 3 ++- > > arch/riscv/include/asm/tlbflush.h | 2 ++ > > arch/riscv/mm/kasan_init.c | 8 ++++++++ > > arch/riscv/mm/tlbflush.c | 5 +++++ > > include/asm-generic/cacheflush.h | 6 ++++++ > > mm/percpu.c | 8 +------- > > 7 files changed, 26 insertions(+), 8 deletions(-) > > > > Any feedback regarding this? On cursory look, it looked fine to me but Dennis is maintaining the percpu tree now. Dennis? Thanks.
Hello, On Wed, Dec 06, 2023 at 09:00:27AM -1000, Tejun Heo wrote: > On Wed, Dec 06, 2023 at 11:08:20AM +0100, Alexandre Ghiti wrote: > > Hi Tejun, > > > > On 10/11/2023 15:07, Alexandre Ghiti wrote: > > > While working with pcpu variables, I noticed that riscv did not support > > > first chunk allocation in the vmalloc area which may be needed as a fallback > > > in case of a sparse NUMA configuration. > > > > > > patch 1 starts by introducing a new function flush_cache_vmap_early() which > > > is needed since a new vmalloc mapping is established and directly accessed: > > > on riscv, this would likely fail in case of a reordered access or if the > > > uarch caches invalid entries in TLB. > > > > > > patch 2 simply enables the page percpu first chunk allocator in riscv. > > > > > > Alexandre Ghiti (2): > > > mm: Introduce flush_cache_vmap_early() and its riscv implementation > > > riscv: Enable pcpu page first chunk allocator > > > > > > arch/riscv/Kconfig | 2 ++ > > > arch/riscv/include/asm/cacheflush.h | 3 ++- > > > arch/riscv/include/asm/tlbflush.h | 2 ++ > > > arch/riscv/mm/kasan_init.c | 8 ++++++++ > > > arch/riscv/mm/tlbflush.c | 5 +++++ > > > include/asm-generic/cacheflush.h | 6 ++++++ > > > mm/percpu.c | 8 +------- > > > 7 files changed, 26 insertions(+), 8 deletions(-) > > > > > > > Any feedback regarding this? > > On cursory look, it looked fine to me but Dennis is maintaining the percpu > tree now. Dennis? > Ah I wasn't sure at the time if we needed this to go through percpu vs risc v. I need to poke tglx and potentially pull some more stuff so I can take it. I regrettably got both the covid and flu vaccines today and feel like a truck hit me. I'll review this tomorrow and make sure it's taken care of for the next merge window. Thanks, Dennis > Thanks. > > -- > tejun
Hello, On Fri, Nov 10, 2023 at 03:07:19PM +0100, Alexandre Ghiti wrote: > While working with pcpu variables, I noticed that riscv did not support > first chunk allocation in the vmalloc area which may be needed as a fallback > in case of a sparse NUMA configuration. > > patch 1 starts by introducing a new function flush_cache_vmap_early() which > is needed since a new vmalloc mapping is established and directly accessed: > on riscv, this would likely fail in case of a reordered access or if the > uarch caches invalid entries in TLB. > > patch 2 simply enables the page percpu first chunk allocator in riscv. > > Alexandre Ghiti (2): > mm: Introduce flush_cache_vmap_early() and its riscv implementation > riscv: Enable pcpu page first chunk allocator > > arch/riscv/Kconfig | 2 ++ > arch/riscv/include/asm/cacheflush.h | 3 ++- > arch/riscv/include/asm/tlbflush.h | 2 ++ > arch/riscv/mm/kasan_init.c | 8 ++++++++ > arch/riscv/mm/tlbflush.c | 5 +++++ > include/asm-generic/cacheflush.h | 6 ++++++ > mm/percpu.c | 8 +------- > 7 files changed, 26 insertions(+), 8 deletions(-) > > -- > 2.39.2 > I've applied this to percpu#for-6.8. Thanks, Dennis