| Message ID | 20180921195954.21574-3-marc.zyngier@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | GICv3 support for kexec/kdump on EFI systems | expand |
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 <marc.zyngier@arm.com> > --- > 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(). 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) >
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 <marc.zyngier@arm.com> >> --- >> 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. 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) >>
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 <marc.zyngier@arm.com> >>> --- >>> 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)) 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) >>> >
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 <marc.zyngier@arm.com> >>>> --- >>>> 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) >>>> >>
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 <marc.zyngier@arm.com> >> --- >> 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(). Yeah, that's a brain fart on my part. I've fixed up. Thanks, M.
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)) #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)
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 <marc.zyngier@arm.com> --- drivers/irqchip/irq-gic-v3-its.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-)