From mboxrd@z Thu Jan 1 00:00:00 1970 From: julien.thierry@arm.com (Julien Thierry) Date: Mon, 24 Sep 2018 11:55:58 +0100 Subject: [PATCH 02/10] irqchip/gic-v3-its: Consolidate LPI_PENDBASE_SZ usage In-Reply-To: References: <20180921195954.21574-1-marc.zyngier@arm.com> <20180921195954.21574-3-marc.zyngier@arm.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 24/09/18 11:54, Suzuki K Poulose wrote: > > > On 24/09/18 11:50, Julien Thierry wrote: >> Hi, >> >> On 24/09/18 11:33, Suzuki K Poulose wrote: >>> Hi Marc, >>> >>> On 21/09/18 20:59, Marc Zyngier wrote: >>>> LPI_PENDING_SZ is always used in conjunction with a max(). Let's >>>> factor this in the definition of the macro, and simplify the rest >>>> of the code. >>>> >>>> Signed-off-by: Marc Zyngier >>>> --- >>>> ? drivers/irqchip/irq-gic-v3-its.c | 12 ++++-------- >>>> ? 1 file changed, 4 insertions(+), 8 deletions(-) >>>> >>>> diff --git a/drivers/irqchip/irq-gic-v3-its.c >>>> b/drivers/irqchip/irq-gic-v3-its.c >>>> index c2df341ff6fa..ed6aab11e019 100644 >>>> --- a/drivers/irqchip/irq-gic-v3-its.c >>>> +++ b/drivers/irqchip/irq-gic-v3-its.c >>>> @@ -62,7 +62,7 @@ static u32 lpi_id_bits; >>>> ?? */ >>>> ? #define LPI_NRBITS??????? lpi_id_bits >>>> ? #define LPI_PROPBASE_SZ??????? ALIGN(BIT(LPI_NRBITS), SZ_64K) >>>> -#define LPI_PENDBASE_SZ??????? ALIGN(BIT(LPI_NRBITS) / 8, SZ_64K) >>>> +#define LPI_PENDBASE_SZ??????? max_t(u32, SZ_64K, >>>> ALIGN(BIT(LPI_NRBITS) / 8, SZ_64K)) >>> >>> minor nit: The ALIGN() already aligns the given value up to the required >>> alignment. So, if the LPI_NRBITS is guaranteed to be non-zero, >>> we could simply drop the max_t(). >>> >> >> Hmmm, Doesn't ALIGN only aligns down? So if "BIT(LPI_NR_BITS) / 8 < >> SZ_64K" (i.e. LPI_NRBITS < 20) The ALIGN(..., SZ_64K) would give 0. > > Isn't it the ALIGN_DOWN(), which aligns it down ? Following the kernel > definitions : > linux/kernel.h -> uapi/linux/kernel.h > ALIGN(x,a) =>???? __ALIGN_KERNEL(x, a) > ??????? \ => __ALIGN_KERNEL_MASK(x, (a -1) > ??????? \ => (((x + (a - 1)) & ~ (a - 1)) Oh, yes you're right, made the wrong assumption. Your suggestion makes sense. Sorry for the noise. Thanks, > > Cheers > Suzuki > > >> >> Thanks, >> >>> Rest looks good to me. >>> >>> Suzuki >>> >>>> ? #define LPI_PROP_DEFAULT_PRIO??? 0xa0 >>>> @@ -1924,12 +1924,9 @@ static int its_alloc_collections(struct >>>> its_node *its) >>>> ? static struct page *its_allocate_pending_table(gfp_t gfp_flags) >>>> ? { >>>> ????? struct page *pend_page; >>>> -??? /* >>>> -???? * The pending pages have to be at least 64kB aligned, >>>> -???? * hence the 'max(LPI_PENDBASE_SZ, SZ_64K)' below. >>>> -???? */ >>>> + >>>> ????? pend_page = alloc_pages(gfp_flags | __GFP_ZERO, >>>> -??????????????? get_order(max_t(u32, LPI_PENDBASE_SZ, SZ_64K))); >>>> +??????????????? get_order(LPI_PENDBASE_SZ)); >>>> ????? if (!pend_page) >>>> ????????? return NULL; >>>> @@ -1941,8 +1938,7 @@ static struct page >>>> *its_allocate_pending_table(gfp_t gfp_flags) >>>> ? static void its_free_pending_table(struct page *pt) >>>> ? { >>>> -??? free_pages((unsigned long)page_address(pt), >>>> -?????????? get_order(max_t(u32, LPI_PENDBASE_SZ, SZ_64K))); >>>> +??? free_pages((unsigned long)page_address(pt), >>>> get_order(LPI_PENDBASE_SZ)); >>>> ? } >>>> ? static void its_cpu_init_lpis(void) >>>> >> -- Julien Thierry