| Message ID | 1573450015-16475-1-git-send-email-yash.shah@sifive.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | RISC-V: Add address map dumper | expand |
On 2019-11-10 10:27 p.m., Yash Shah wrote: > Add support for dumping the kernel address space layout to the console. > User can enable CONFIG_DEBUG_VM_LAYOUT to dump the virtual memory region > into dmesg buffer during boot-up. Cool, I'd find this useful. Though, is there any reason we don't do this more generally for all architectures? > Signed-off-by: Yash Shah <yash.shah@sifive.com> > --- > This patch is based on Linux 5.4-rc6 and tested on SiFive HiFive Unleashed > board. > --- > arch/riscv/Kconfig.debug | 9 +++++++++ > arch/riscv/mm/init.c | 30 ++++++++++++++++++++++++++++++ > 2 files changed, 39 insertions(+) > > diff --git a/arch/riscv/Kconfig.debug b/arch/riscv/Kconfig.debug > index e69de29..cdedfd3 100644 > --- a/arch/riscv/Kconfig.debug > +++ b/arch/riscv/Kconfig.debug > @@ -0,0 +1,9 @@ > +config DEBUG_VM_LAYOUT > + bool "Print virtual memory layout on boot up" > + depends on DEBUG_KERNEL > + help > + Say Y here if you want to dump the kernel virtual memory layout to > + dmesg log on boot up. This information is only useful for kernel > + developers who are working in architecture specific areas of the > + kernel. It is probably not a good idea to enable this feature in a > + production kernel. > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > index 79cfb35..fcb8144 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -55,6 +55,36 @@ void __init mem_init(void) > memblock_free_all(); > > mem_init_print_info(NULL); > +#ifdef CONFIG_DEBUG_VM_LAYOUT Generally, it's best to avoid #ifdefs inside functions, it's even counter-indicated in the style guide[1]. > +#define MLK(b, t) b, t, (((t) - (b)) >> 10) > +#define MLM(b, t) b, t, (((t) - (b)) >> 20) > +#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) I personally find these inline defines rather ugly. Maybe it would be better to have a helper function that prints a single line. Also seems like MLK and MLK_ROUNDUP could be the same assuming the entries in MLK are aligned... > + > + pr_notice("Virtual kernel memory layout:\n" > + " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n" > + " vmemmap : 0x%08lx - 0x%08lx (%4ld MB)\n" > + " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" > + " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n" > + " .init : 0x%px - 0x%px (%4td kB)\n" > + " .text : 0x%px - 0x%px (%4td kB)\n" > + " .data : 0x%px - 0x%px (%4td kB)\n" > + " .bss : 0x%px - 0x%px (%4td kB)\n", > + > + MLK(FIXADDR_START, FIXADDR_TOP), > + MLM(VMEMMAP_START, VMEMMAP_END), > + MLM(VMALLOC_START, VMALLOC_END), > + MLM(PAGE_OFFSET, (unsigned long)high_memory), > + > + MLK_ROUNDUP(__init_begin, __init_end), > + MLK_ROUNDUP(_text, _etext), > + MLK_ROUNDUP(_sdata, _edata), > + MLK_ROUNDUP(__bss_start, __bss_stop)); > + > +#undef MLK > +#undef MLM > +#undef MLK_ROUNDUP > +#endif > } > > #ifdef CONFIG_BLK_DEV_INITRD Thanks, Logan [1] https://www.kernel.org/doc/html/latest/process/coding-style.html#conditional-compilation
On Mon, Nov 11, 2019 at 11:14:30AM -0700, Logan Gunthorpe wrote: > > > On 2019-11-10 10:27 p.m., Yash Shah wrote: > > Add support for dumping the kernel address space layout to the console. > > User can enable CONFIG_DEBUG_VM_LAYOUT to dump the virtual memory region > > into dmesg buffer during boot-up. > > Cool, I'd find this useful. Though, is there any reason we don't do this > more generally for all architectures? Some architectures do this, some don't. I don't think there's a particular reason we don't do this generally, it just evolved that way :) > > Signed-off-by: Yash Shah <yash.shah@sifive.com> > > --- > > This patch is based on Linux 5.4-rc6 and tested on SiFive HiFive Unleashed > > board. > > --- > > arch/riscv/Kconfig.debug | 9 +++++++++ > > arch/riscv/mm/init.c | 30 ++++++++++++++++++++++++++++++ > > 2 files changed, 39 insertions(+) > > > > diff --git a/arch/riscv/Kconfig.debug b/arch/riscv/Kconfig.debug > > index e69de29..cdedfd3 100644 > > --- a/arch/riscv/Kconfig.debug > > +++ b/arch/riscv/Kconfig.debug > > @@ -0,0 +1,9 @@ > > +config DEBUG_VM_LAYOUT > > + bool "Print virtual memory layout on boot up" > > + depends on DEBUG_KERNEL > > + help > > + Say Y here if you want to dump the kernel virtual memory layout to > > + dmesg log on boot up. This information is only useful for kernel > > + developers who are working in architecture specific areas of the > > + kernel. It is probably not a good idea to enable this feature in a > > + production kernel. > > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > > index 79cfb35..fcb8144 100644 > > --- a/arch/riscv/mm/init.c > > +++ b/arch/riscv/mm/init.c > > @@ -55,6 +55,36 @@ void __init mem_init(void) > > memblock_free_all(); > > > > mem_init_print_info(NULL); > > +#ifdef CONFIG_DEBUG_VM_LAYOUT > > Generally, it's best to avoid #ifdefs inside functions, it's even > counter-indicated in the style guide[1]. > > > +#define MLK(b, t) b, t, (((t) - (b)) >> 10) > > +#define MLM(b, t) b, t, (((t) - (b)) >> 20) > > +#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) > > I personally find these inline defines rather ugly. Maybe it would be > better to have a helper function that prints a single line. Also seems > like MLK and MLK_ROUNDUP could be the same assuming the entries in MLK > are aligned... > > > + > > + pr_notice("Virtual kernel memory layout:\n" > > + " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n" > > + " vmemmap : 0x%08lx - 0x%08lx (%4ld MB)\n" > > + " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" > > + " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n" > > + " .init : 0x%px - 0x%px (%4td kB)\n" > > + " .text : 0x%px - 0x%px (%4td kB)\n" > > + " .data : 0x%px - 0x%px (%4td kB)\n" > > + " .bss : 0x%px - 0x%px (%4td kB)\n", > > + > > + MLK(FIXADDR_START, FIXADDR_TOP), > > + MLM(VMEMMAP_START, VMEMMAP_END), > > + MLM(VMALLOC_START, VMALLOC_END), > > + MLM(PAGE_OFFSET, (unsigned long)high_memory), > > + > > + MLK_ROUNDUP(__init_begin, __init_end), > > + MLK_ROUNDUP(_text, _etext), > > + MLK_ROUNDUP(_sdata, _edata), > > + MLK_ROUNDUP(__bss_start, __bss_stop)); > > + > > +#undef MLK > > +#undef MLM > > +#undef MLK_ROUNDUP > > +#endif > > } > > > > #ifdef CONFIG_BLK_DEV_INITRD > > Thanks, > > Logan > > [1] > https://www.kernel.org/doc/html/latest/process/coding-style.html#conditional-compilation
Hi, On Mon, Nov 11, 2019 at 05:27:25AM +0000, Yash Shah wrote: > Add support for dumping the kernel address space layout to the console. > User can enable CONFIG_DEBUG_VM_LAYOUT to dump the virtual memory region > into dmesg buffer during boot-up. > > Signed-off-by: Yash Shah <yash.shah@sifive.com> > --- > This patch is based on Linux 5.4-rc6 and tested on SiFive HiFive Unleashed > board. > --- > arch/riscv/Kconfig.debug | 9 +++++++++ > arch/riscv/mm/init.c | 30 ++++++++++++++++++++++++++++++ > 2 files changed, 39 insertions(+) > > diff --git a/arch/riscv/Kconfig.debug b/arch/riscv/Kconfig.debug > index e69de29..cdedfd3 100644 > --- a/arch/riscv/Kconfig.debug > +++ b/arch/riscv/Kconfig.debug > @@ -0,0 +1,9 @@ > +config DEBUG_VM_LAYOUT I believe this could be enabled when CONFIG_DEBUG_VM=y without adding yet another architecture specific Kconfig option. > + bool "Print virtual memory layout on boot up" > + depends on DEBUG_KERNEL > + help > + Say Y here if you want to dump the kernel virtual memory layout to > + dmesg log on boot up. This information is only useful for kernel > + developers who are working in architecture specific areas of the > + kernel. It is probably not a good idea to enable this feature in a > + production kernel. > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > index 79cfb35..fcb8144 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -55,6 +55,36 @@ void __init mem_init(void) > memblock_free_all(); > > mem_init_print_info(NULL); > +#ifdef CONFIG_DEBUG_VM_LAYOUT > +#define MLK(b, t) b, t, (((t) - (b)) >> 10) > +#define MLM(b, t) b, t, (((t) - (b)) >> 20) > +#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) > + > + > + pr_notice("Virtual kernel memory layout:\n" > + " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n" > + " vmemmap : 0x%08lx - 0x%08lx (%4ld MB)\n" > + " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" > + " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n" > + " .init : 0x%px - 0x%px (%4td kB)\n" > + " .text : 0x%px - 0x%px (%4td kB)\n" > + " .data : 0x%px - 0x%px (%4td kB)\n" > + " .bss : 0x%px - 0x%px (%4td kB)\n", > + > + MLK(FIXADDR_START, FIXADDR_TOP), > + MLM(VMEMMAP_START, VMEMMAP_END), > + MLM(VMALLOC_START, VMALLOC_END), > + MLM(PAGE_OFFSET, (unsigned long)high_memory), > + > + MLK_ROUNDUP(__init_begin, __init_end), > + MLK_ROUNDUP(_text, _etext), > + MLK_ROUNDUP(_sdata, _edata), > + MLK_ROUNDUP(__bss_start, __bss_stop)); > + > +#undef MLK > +#undef MLM > +#undef MLK_ROUNDUP > +#endif > } > > #ifdef CONFIG_BLK_DEV_INITRD > -- > 2.7.4 >
> On 2019-11-10 10:27 p.m., Yash Shah wrote: > > Add support for dumping the kernel address space layout to the console. > > User can enable CONFIG_DEBUG_VM_LAYOUT to dump the virtual > memory > > region into dmesg buffer during boot-up. > > Cool, I'd find this useful. Though, is there any reason we don't do this more > generally for all architectures? > > > Signed-off-by: Yash Shah <yash.shah@sifive.com> > > --- > > This patch is based on Linux 5.4-rc6 and tested on SiFive HiFive > > Unleashed board. > > --- > > arch/riscv/Kconfig.debug | 9 +++++++++ > > arch/riscv/mm/init.c | 30 ++++++++++++++++++++++++++++++ > > 2 files changed, 39 insertions(+) > > ... > > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index > > 79cfb35..fcb8144 100644 > > --- a/arch/riscv/mm/init.c > > +++ b/arch/riscv/mm/init.c > > @@ -55,6 +55,36 @@ void __init mem_init(void) > > memblock_free_all(); > > > > mem_init_print_info(NULL); > > +#ifdef CONFIG_DEBUG_VM_LAYOUT > > Generally, it's best to avoid #ifdefs inside functions, it's even counter- > indicated in the style guide[1]. Yes, I will move out the print logic as a separate function and guard it with #ifdefs > > > +#define MLK(b, t) b, t, (((t) - (b)) >> 10) #define MLM(b, t) b, t, > > +(((t) - (b)) >> 20) #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) > > +- (b)), SZ_1K) > > I personally find these inline defines rather ugly. Maybe it would be better to > have a helper function that prints a single line. Also seems like MLK and > MLK_ROUNDUP could be the same assuming the entries in MLK are > aligned... > Sure, will convert this macros into helper inline functions and will also drop MLK_ROUNDUP. > > Thanks, > > Logan > Thanks for your comments! - Yash > [1] > https://www.kernel.org/doc/html/latest/process/coding- > style.html#conditional-compilation > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv
> -----Original Message----- > From: Mike Rapoport <rppt@linux.ibm.com> > Sent: 12 November 2019 03:27 > To: Yash Shah <yash.shah@sifive.com> > Cc: Paul Walmsley ( Sifive) <paul.walmsley@sifive.com>; linux- > riscv@lists.infradead.org; linux-kernel@vger.kernel.org; > palmer@dabbelt.com; aou@eecs.berkeley.edu; Anup.Patel@wdc.com; > logang@deltatee.com; ren_guo@c-sky.com; bmeng.cn@gmail.com; > tglx@linutronix.de; Sachin Ghadi <sachin.ghadi@sifive.com> > Subject: Re: [PATCH] RISC-V: Add address map dumper > > Hi, > > On Mon, Nov 11, 2019 at 05:27:25AM +0000, Yash Shah wrote: > > Add support for dumping the kernel address space layout to the console. > > User can enable CONFIG_DEBUG_VM_LAYOUT to dump the virtual > memory > > region into dmesg buffer during boot-up. > > > > Signed-off-by: Yash Shah <yash.shah@sifive.com> > > --- > > This patch is based on Linux 5.4-rc6 and tested on SiFive HiFive > > Unleashed board. > > --- > > arch/riscv/Kconfig.debug | 9 +++++++++ > > arch/riscv/mm/init.c | 30 ++++++++++++++++++++++++++++++ > > 2 files changed, 39 insertions(+) > > > > diff --git a/arch/riscv/Kconfig.debug b/arch/riscv/Kconfig.debug index > > e69de29..cdedfd3 100644 > > --- a/arch/riscv/Kconfig.debug > > +++ b/arch/riscv/Kconfig.debug > > @@ -0,0 +1,9 @@ > > +config DEBUG_VM_LAYOUT > > I believe this could be enabled when CONFIG_DEBUG_VM=y without adding > yet another architecture specific Kconfig option. Oh yes, I will drop the newly added kconfig option in v2. > -- > Sincerely yours, > Mike. Thanks for your comment! - Yash
diff --git a/arch/riscv/Kconfig.debug b/arch/riscv/Kconfig.debug index e69de29..cdedfd3 100644 --- a/arch/riscv/Kconfig.debug +++ b/arch/riscv/Kconfig.debug @@ -0,0 +1,9 @@ +config DEBUG_VM_LAYOUT + bool "Print virtual memory layout on boot up" + depends on DEBUG_KERNEL + help + Say Y here if you want to dump the kernel virtual memory layout to + dmesg log on boot up. This information is only useful for kernel + developers who are working in architecture specific areas of the + kernel. It is probably not a good idea to enable this feature in a + production kernel. diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 79cfb35..fcb8144 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -55,6 +55,36 @@ void __init mem_init(void) memblock_free_all(); mem_init_print_info(NULL); +#ifdef CONFIG_DEBUG_VM_LAYOUT +#define MLK(b, t) b, t, (((t) - (b)) >> 10) +#define MLM(b, t) b, t, (((t) - (b)) >> 20) +#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K) + + + pr_notice("Virtual kernel memory layout:\n" + " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n" + " vmemmap : 0x%08lx - 0x%08lx (%4ld MB)\n" + " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n" + " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n" + " .init : 0x%px - 0x%px (%4td kB)\n" + " .text : 0x%px - 0x%px (%4td kB)\n" + " .data : 0x%px - 0x%px (%4td kB)\n" + " .bss : 0x%px - 0x%px (%4td kB)\n", + + MLK(FIXADDR_START, FIXADDR_TOP), + MLM(VMEMMAP_START, VMEMMAP_END), + MLM(VMALLOC_START, VMALLOC_END), + MLM(PAGE_OFFSET, (unsigned long)high_memory), + + MLK_ROUNDUP(__init_begin, __init_end), + MLK_ROUNDUP(_text, _etext), + MLK_ROUNDUP(_sdata, _edata), + MLK_ROUNDUP(__bss_start, __bss_stop)); + +#undef MLK +#undef MLM +#undef MLK_ROUNDUP +#endif } #ifdef CONFIG_BLK_DEV_INITRD
Add support for dumping the kernel address space layout to the console. User can enable CONFIG_DEBUG_VM_LAYOUT to dump the virtual memory region into dmesg buffer during boot-up. Signed-off-by: Yash Shah <yash.shah@sifive.com> --- This patch is based on Linux 5.4-rc6 and tested on SiFive HiFive Unleashed board. --- arch/riscv/Kconfig.debug | 9 +++++++++ arch/riscv/mm/init.c | 30 ++++++++++++++++++++++++++++++ 2 files changed, 39 insertions(+)