* [PATCH 0/2] MAAR SMP fix @ 2015-09-22 19:08 ` Paul Burton 0 siblings, 0 replies; 8+ messages in thread From: Paul Burton @ 2015-09-22 19:08 UTC (permalink / raw) To: linux-mips Cc: Paul Burton, Rusty Russell, Steven J. Hill, Bjorn Helgaas, David Hildenbrand, Andrew Bresticker, linux-kernel, Aaro Koskinen, James Hogan, Markos Chandras, Ingo Molnar, Ralf Baechle, Alex Smith, Peter Zijlstra (Intel) This series improves support for Memory Accessibility Attribute Registers (MAARs) by printing their configuration during boot and by applying the configuration to secondary CPUs, which have their own independent MAAR state. Paul Burton (2): MIPS: print MAAR configuration during boot MIPS: initialise MAARs on secondary CPUs arch/mips/include/asm/maar.h | 9 +++++++ arch/mips/kernel/smp.c | 2 ++ arch/mips/mm/init.c | 57 +++++++++++++++++++++++++++++++++++++++++--- 3 files changed, 65 insertions(+), 3 deletions(-) -- 2.5.3 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH 0/2] MAAR SMP fix @ 2015-09-22 19:08 ` Paul Burton 0 siblings, 0 replies; 8+ messages in thread From: Paul Burton @ 2015-09-22 19:08 UTC (permalink / raw) To: linux-mips Cc: Paul Burton, Rusty Russell, Steven J. Hill, Bjorn Helgaas, David Hildenbrand, Andrew Bresticker, linux-kernel, Aaro Koskinen, James Hogan, Markos Chandras, Ingo Molnar, Ralf Baechle, Alex Smith, Peter Zijlstra (Intel) This series improves support for Memory Accessibility Attribute Registers (MAARs) by printing their configuration during boot and by applying the configuration to secondary CPUs, which have their own independent MAAR state. Paul Burton (2): MIPS: print MAAR configuration during boot MIPS: initialise MAARs on secondary CPUs arch/mips/include/asm/maar.h | 9 +++++++ arch/mips/kernel/smp.c | 2 ++ arch/mips/mm/init.c | 57 +++++++++++++++++++++++++++++++++++++++++--- 3 files changed, 65 insertions(+), 3 deletions(-) -- 2.5.3 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH 1/2] MIPS: print MAAR configuration during boot @ 2015-09-22 19:08 ` Paul Burton 0 siblings, 0 replies; 8+ messages in thread From: Paul Burton @ 2015-09-22 19:08 UTC (permalink / raw) To: linux-mips Cc: Paul Burton, Steven J. Hill, David Hildenbrand, linux-kernel, Ingo Molnar, Ralf Baechle, Peter Zijlstra (Intel) Verifying that the MAAR configuration is as expected is useful when debugging the performance of a system. Print out the memory regions configured via MAAR along with their attributes. Signed-off-by: Paul Burton <paul.burton@imgtec.com> --- arch/mips/mm/init.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c index 66d0f49..cbef5c2 100644 --- a/arch/mips/mm/init.c +++ b/arch/mips/mm/init.c @@ -373,6 +373,7 @@ unsigned __weak platform_maar_init(unsigned num_pairs) static void maar_init(void) { unsigned num_maars, used, i; + phys_addr_t lower, upper, attr; if (!cpu_has_maar) return; @@ -395,6 +396,34 @@ static void maar_init(void) write_c0_maar(0); back_to_back_c0_hazard(); } + + pr_info("MAAR configuration:\n"); + for (i = 0; i < num_maars; i += 2) { + write_c0_maari(i); + back_to_back_c0_hazard(); + upper = read_c0_maar(); + + write_c0_maari(i + 1); + back_to_back_c0_hazard(); + lower = read_c0_maar(); + + attr = lower & upper; + lower = (lower & MIPS_MAAR_ADDR) << 4; + upper = ((upper & MIPS_MAAR_ADDR) << 4) | 0xffff; + + pr_info(" [%d]: ", i / 2); + if (!(attr & MIPS_MAAR_V)) { + pr_cont("disabled\n"); + continue; + } + + pr_cont("%pa-%pa", &lower, &upper); + + if (attr & MIPS_MAAR_S) + pr_cont(" speculate"); + + pr_cont("\n"); + } } void __init mem_init(void) -- 2.5.3 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH 1/2] MIPS: print MAAR configuration during boot @ 2015-09-22 19:08 ` Paul Burton 0 siblings, 0 replies; 8+ messages in thread From: Paul Burton @ 2015-09-22 19:08 UTC (permalink / raw) To: linux-mips Cc: Paul Burton, Steven J. Hill, David Hildenbrand, linux-kernel, Ingo Molnar, Ralf Baechle, Peter Zijlstra (Intel) Verifying that the MAAR configuration is as expected is useful when debugging the performance of a system. Print out the memory regions configured via MAAR along with their attributes. Signed-off-by: Paul Burton <paul.burton@imgtec.com> --- arch/mips/mm/init.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c index 66d0f49..cbef5c2 100644 --- a/arch/mips/mm/init.c +++ b/arch/mips/mm/init.c @@ -373,6 +373,7 @@ unsigned __weak platform_maar_init(unsigned num_pairs) static void maar_init(void) { unsigned num_maars, used, i; + phys_addr_t lower, upper, attr; if (!cpu_has_maar) return; @@ -395,6 +396,34 @@ static void maar_init(void) write_c0_maar(0); back_to_back_c0_hazard(); } + + pr_info("MAAR configuration:\n"); + for (i = 0; i < num_maars; i += 2) { + write_c0_maari(i); + back_to_back_c0_hazard(); + upper = read_c0_maar(); + + write_c0_maari(i + 1); + back_to_back_c0_hazard(); + lower = read_c0_maar(); + + attr = lower & upper; + lower = (lower & MIPS_MAAR_ADDR) << 4; + upper = ((upper & MIPS_MAAR_ADDR) << 4) | 0xffff; + + pr_info(" [%d]: ", i / 2); + if (!(attr & MIPS_MAAR_V)) { + pr_cont("disabled\n"); + continue; + } + + pr_cont("%pa-%pa", &lower, &upper); + + if (attr & MIPS_MAAR_S) + pr_cont(" speculate"); + + pr_cont("\n"); + } } void __init mem_init(void) -- 2.5.3 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH 2/2] MIPS: initialise MAARs on secondary CPUs @ 2015-09-22 19:08 ` Paul Burton 0 siblings, 0 replies; 8+ messages in thread From: Paul Burton @ 2015-09-22 19:08 UTC (permalink / raw) To: linux-mips Cc: Paul Burton, Rusty Russell, Steven J. Hill, Andrew Bresticker, Bjorn Helgaas, David Hildenbrand, linux-kernel, Aaro Koskinen, James Hogan, Markos Chandras, Ingo Molnar, Ralf Baechle, Alex Smith MAARs should be initialised on each CPU (or rather, core) in the system in order to achieve consistent behaviour & performance. Previously they have only been initialised on the boot CPU which leads to performance problems if tasks are later scheduled on a secondary CPU, particularly if those tasks make use of unaligned vector accesses where some CPUs don't handle any cases in hardware for non-speculative memory regions. Fix this by recording the MAAR configuration from the boot CPU and applying it to secondary CPUs as part of their bringup. Reported-by: Doug Gilmore <doug.gilmore@imgtec.com> Signed-off-by: Paul Burton <paul.burton@imgtec.com> --- arch/mips/include/asm/maar.h | 9 +++++++++ arch/mips/kernel/smp.c | 2 ++ arch/mips/mm/init.c | 28 +++++++++++++++++++++++++--- 3 files changed, 36 insertions(+), 3 deletions(-) diff --git a/arch/mips/include/asm/maar.h b/arch/mips/include/asm/maar.h index b02891f..21d9607 100644 --- a/arch/mips/include/asm/maar.h +++ b/arch/mips/include/asm/maar.h @@ -66,6 +66,15 @@ static inline void write_maar_pair(unsigned idx, phys_addr_t lower, } /** + * maar_init() - initialise MAARs + * + * Performs initialisation of MAARs for the current CPU, making use of the + * platforms implementation of platform_maar_init where necessary and + * duplicating the setup it provides on secondary CPUs. + */ +extern void maar_init(void); + +/** * struct maar_config - MAAR configuration data * @lower: The lowest address that the MAAR pair will affect. Must be * aligned to a 2^16 byte boundary. diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c index a31896c..bd4385a 100644 --- a/arch/mips/kernel/smp.c +++ b/arch/mips/kernel/smp.c @@ -42,6 +42,7 @@ #include <asm/mmu_context.h> #include <asm/time.h> #include <asm/setup.h> +#include <asm/maar.h> cpumask_t cpu_callin_map; /* Bitmask of started secondaries */ @@ -157,6 +158,7 @@ asmlinkage void start_secondary(void) mips_clockevent_init(); mp_ops->init_secondary(); cpu_report(); + maar_init(); /* * XXX parity protection should be folded in here when it's converted diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c index cbef5c2..5f3c5b1 100644 --- a/arch/mips/mm/init.c +++ b/arch/mips/mm/init.c @@ -44,6 +44,7 @@ #include <asm/pgalloc.h> #include <asm/tlb.h> #include <asm/fixmap.h> +#include <asm/maar.h> /* * We have up to 8 empty zeroed pages so we can map one of the right colour @@ -370,10 +371,14 @@ unsigned __weak platform_maar_init(unsigned num_pairs) return num_configured; } -static void maar_init(void) +void maar_init(void) { unsigned num_maars, used, i; phys_addr_t lower, upper, attr; + static struct { + struct maar_config cfgs[3]; + unsigned used; + } recorded = { { { 0 } }, 0 }; if (!cpu_has_maar) return; @@ -386,8 +391,14 @@ static void maar_init(void) /* MAARs should be in pairs */ WARN_ON(num_maars % 2); - /* Configure the required MAARs */ - used = platform_maar_init(num_maars / 2); + /* Set MAARs using values we recorded already */ + if (recorded.used) { + used = maar_config(recorded.cfgs, recorded.used, num_maars / 2); + BUG_ON(used != recorded.used); + } else { + /* Configure the required MAARs */ + used = platform_maar_init(num_maars / 2); + } /* Disable any further MAARs */ for (i = (used * 2); i < num_maars; i++) { @@ -397,6 +408,9 @@ static void maar_init(void) back_to_back_c0_hazard(); } + if (recorded.used) + return; + pr_info("MAAR configuration:\n"); for (i = 0; i < num_maars; i += 2) { write_c0_maari(i); @@ -423,6 +437,14 @@ static void maar_init(void) pr_cont(" speculate"); pr_cont("\n"); + + /* Record the setup for use on secondary CPUs */ + if (used <= ARRAY_SIZE(recorded.cfgs)) { + recorded.cfgs[recorded.used].lower = lower; + recorded.cfgs[recorded.used].upper = upper; + recorded.cfgs[recorded.used].attrs = attr; + recorded.used++; + } } } -- 2.5.3 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* [PATCH 2/2] MIPS: initialise MAARs on secondary CPUs @ 2015-09-22 19:08 ` Paul Burton 0 siblings, 0 replies; 8+ messages in thread From: Paul Burton @ 2015-09-22 19:08 UTC (permalink / raw) To: linux-mips Cc: Paul Burton, Rusty Russell, Steven J. Hill, Andrew Bresticker, Bjorn Helgaas, David Hildenbrand, linux-kernel, Aaro Koskinen, James Hogan, Markos Chandras, Ingo Molnar, Ralf Baechle, Alex Smith MAARs should be initialised on each CPU (or rather, core) in the system in order to achieve consistent behaviour & performance. Previously they have only been initialised on the boot CPU which leads to performance problems if tasks are later scheduled on a secondary CPU, particularly if those tasks make use of unaligned vector accesses where some CPUs don't handle any cases in hardware for non-speculative memory regions. Fix this by recording the MAAR configuration from the boot CPU and applying it to secondary CPUs as part of their bringup. Reported-by: Doug Gilmore <doug.gilmore@imgtec.com> Signed-off-by: Paul Burton <paul.burton@imgtec.com> --- arch/mips/include/asm/maar.h | 9 +++++++++ arch/mips/kernel/smp.c | 2 ++ arch/mips/mm/init.c | 28 +++++++++++++++++++++++++--- 3 files changed, 36 insertions(+), 3 deletions(-) diff --git a/arch/mips/include/asm/maar.h b/arch/mips/include/asm/maar.h index b02891f..21d9607 100644 --- a/arch/mips/include/asm/maar.h +++ b/arch/mips/include/asm/maar.h @@ -66,6 +66,15 @@ static inline void write_maar_pair(unsigned idx, phys_addr_t lower, } /** + * maar_init() - initialise MAARs + * + * Performs initialisation of MAARs for the current CPU, making use of the + * platforms implementation of platform_maar_init where necessary and + * duplicating the setup it provides on secondary CPUs. + */ +extern void maar_init(void); + +/** * struct maar_config - MAAR configuration data * @lower: The lowest address that the MAAR pair will affect. Must be * aligned to a 2^16 byte boundary. diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c index a31896c..bd4385a 100644 --- a/arch/mips/kernel/smp.c +++ b/arch/mips/kernel/smp.c @@ -42,6 +42,7 @@ #include <asm/mmu_context.h> #include <asm/time.h> #include <asm/setup.h> +#include <asm/maar.h> cpumask_t cpu_callin_map; /* Bitmask of started secondaries */ @@ -157,6 +158,7 @@ asmlinkage void start_secondary(void) mips_clockevent_init(); mp_ops->init_secondary(); cpu_report(); + maar_init(); /* * XXX parity protection should be folded in here when it's converted diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c index cbef5c2..5f3c5b1 100644 --- a/arch/mips/mm/init.c +++ b/arch/mips/mm/init.c @@ -44,6 +44,7 @@ #include <asm/pgalloc.h> #include <asm/tlb.h> #include <asm/fixmap.h> +#include <asm/maar.h> /* * We have up to 8 empty zeroed pages so we can map one of the right colour @@ -370,10 +371,14 @@ unsigned __weak platform_maar_init(unsigned num_pairs) return num_configured; } -static void maar_init(void) +void maar_init(void) { unsigned num_maars, used, i; phys_addr_t lower, upper, attr; + static struct { + struct maar_config cfgs[3]; + unsigned used; + } recorded = { { { 0 } }, 0 }; if (!cpu_has_maar) return; @@ -386,8 +391,14 @@ static void maar_init(void) /* MAARs should be in pairs */ WARN_ON(num_maars % 2); - /* Configure the required MAARs */ - used = platform_maar_init(num_maars / 2); + /* Set MAARs using values we recorded already */ + if (recorded.used) { + used = maar_config(recorded.cfgs, recorded.used, num_maars / 2); + BUG_ON(used != recorded.used); + } else { + /* Configure the required MAARs */ + used = platform_maar_init(num_maars / 2); + } /* Disable any further MAARs */ for (i = (used * 2); i < num_maars; i++) { @@ -397,6 +408,9 @@ static void maar_init(void) back_to_back_c0_hazard(); } + if (recorded.used) + return; + pr_info("MAAR configuration:\n"); for (i = 0; i < num_maars; i += 2) { write_c0_maari(i); @@ -423,6 +437,14 @@ static void maar_init(void) pr_cont(" speculate"); pr_cont("\n"); + + /* Record the setup for use on secondary CPUs */ + if (used <= ARRAY_SIZE(recorded.cfgs)) { + recorded.cfgs[recorded.used].lower = lower; + recorded.cfgs[recorded.used].upper = upper; + recorded.cfgs[recorded.used].attrs = attr; + recorded.used++; + } } } -- 2.5.3 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH 2/2] MIPS: initialise MAARs on secondary CPUs @ 2015-09-24 8:23 ` Markos Chandras 0 siblings, 0 replies; 8+ messages in thread From: Markos Chandras @ 2015-09-24 8:23 UTC (permalink / raw) To: Paul Burton, linux-mips Cc: Rusty Russell, Steven J. Hill, Andrew Bresticker, Bjorn Helgaas, David Hildenbrand, linux-kernel, Aaro Koskinen, James Hogan, Ingo Molnar, Ralf Baechle, Alex Smith On 09/22/2015 08:08 PM, Paul Burton wrote: > MAARs should be initialised on each CPU (or rather, core) in the system > in order to achieve consistent behaviour & performance. Previously they > have only been initialised on the boot CPU which leads to performance > problems if tasks are later scheduled on a secondary CPU, particularly > if those tasks make use of unaligned vector accesses where some CPUs > don't handle any cases in hardware for non-speculative memory regions. > Fix this by recording the MAAR configuration from the boot CPU and > applying it to secondary CPUs as part of their bringup. > > Reported-by: Doug Gilmore <doug.gilmore@imgtec.com> > Signed-off-by: Paul Burton <paul.burton@imgtec.com> > --- > > arch/mips/include/asm/maar.h | 9 +++++++++ > arch/mips/kernel/smp.c | 2 ++ > arch/mips/mm/init.c | 28 +++++++++++++++++++++++++--- > 3 files changed, 36 insertions(+), 3 deletions(-) > > diff --git a/arch/mips/include/asm/maar.h b/arch/mips/include/asm/maar.h > index b02891f..21d9607 100644 > --- a/arch/mips/include/asm/maar.h > +++ b/arch/mips/include/asm/maar.h > @@ -66,6 +66,15 @@ static inline void write_maar_pair(unsigned idx, phys_addr_t lower, > } > > /** > + * maar_init() - initialise MAARs > + * > + * Performs initialisation of MAARs for the current CPU, making use of the > + * platforms implementation of platform_maar_init where necessary and > + * duplicating the setup it provides on secondary CPUs. > + */ > +extern void maar_init(void); > + > +/** > * struct maar_config - MAAR configuration data > * @lower: The lowest address that the MAAR pair will affect. Must be > * aligned to a 2^16 byte boundary. > diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c > index a31896c..bd4385a 100644 > --- a/arch/mips/kernel/smp.c > +++ b/arch/mips/kernel/smp.c > @@ -42,6 +42,7 @@ > #include <asm/mmu_context.h> > #include <asm/time.h> > #include <asm/setup.h> > +#include <asm/maar.h> > > cpumask_t cpu_callin_map; /* Bitmask of started secondaries */ > > @@ -157,6 +158,7 @@ asmlinkage void start_secondary(void) > mips_clockevent_init(); > mp_ops->init_secondary(); > cpu_report(); > + maar_init(); > Hi, This breaks the ip27_defconfig in both upstream-sfr and linux-next arch/mips/built-in.o: In function `start_secondary': (.text+0x123e4): undefined reference to `maar_init' Makefile:944: recipe for target 'vmlinux' failed -- markos ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH 2/2] MIPS: initialise MAARs on secondary CPUs @ 2015-09-24 8:23 ` Markos Chandras 0 siblings, 0 replies; 8+ messages in thread From: Markos Chandras @ 2015-09-24 8:23 UTC (permalink / raw) To: Paul Burton, linux-mips Cc: Rusty Russell, Steven J. Hill, Andrew Bresticker, Bjorn Helgaas, David Hildenbrand, linux-kernel, Aaro Koskinen, James Hogan, Ingo Molnar, Ralf Baechle, Alex Smith On 09/22/2015 08:08 PM, Paul Burton wrote: > MAARs should be initialised on each CPU (or rather, core) in the system > in order to achieve consistent behaviour & performance. Previously they > have only been initialised on the boot CPU which leads to performance > problems if tasks are later scheduled on a secondary CPU, particularly > if those tasks make use of unaligned vector accesses where some CPUs > don't handle any cases in hardware for non-speculative memory regions. > Fix this by recording the MAAR configuration from the boot CPU and > applying it to secondary CPUs as part of their bringup. > > Reported-by: Doug Gilmore <doug.gilmore@imgtec.com> > Signed-off-by: Paul Burton <paul.burton@imgtec.com> > --- > > arch/mips/include/asm/maar.h | 9 +++++++++ > arch/mips/kernel/smp.c | 2 ++ > arch/mips/mm/init.c | 28 +++++++++++++++++++++++++--- > 3 files changed, 36 insertions(+), 3 deletions(-) > > diff --git a/arch/mips/include/asm/maar.h b/arch/mips/include/asm/maar.h > index b02891f..21d9607 100644 > --- a/arch/mips/include/asm/maar.h > +++ b/arch/mips/include/asm/maar.h > @@ -66,6 +66,15 @@ static inline void write_maar_pair(unsigned idx, phys_addr_t lower, > } > > /** > + * maar_init() - initialise MAARs > + * > + * Performs initialisation of MAARs for the current CPU, making use of the > + * platforms implementation of platform_maar_init where necessary and > + * duplicating the setup it provides on secondary CPUs. > + */ > +extern void maar_init(void); > + > +/** > * struct maar_config - MAAR configuration data > * @lower: The lowest address that the MAAR pair will affect. Must be > * aligned to a 2^16 byte boundary. > diff --git a/arch/mips/kernel/smp.c b/arch/mips/kernel/smp.c > index a31896c..bd4385a 100644 > --- a/arch/mips/kernel/smp.c > +++ b/arch/mips/kernel/smp.c > @@ -42,6 +42,7 @@ > #include <asm/mmu_context.h> > #include <asm/time.h> > #include <asm/setup.h> > +#include <asm/maar.h> > > cpumask_t cpu_callin_map; /* Bitmask of started secondaries */ > > @@ -157,6 +158,7 @@ asmlinkage void start_secondary(void) > mips_clockevent_init(); > mp_ops->init_secondary(); > cpu_report(); > + maar_init(); > Hi, This breaks the ip27_defconfig in both upstream-sfr and linux-next arch/mips/built-in.o: In function `start_secondary': (.text+0x123e4): undefined reference to `maar_init' Makefile:944: recipe for target 'vmlinux' failed -- markos ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2015-09-24 8:23 UTC | newest] Thread overview: 8+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2015-09-22 19:08 [PATCH 0/2] MAAR SMP fix Paul Burton 2015-09-22 19:08 ` Paul Burton 2015-09-22 19:08 ` [PATCH 1/2] MIPS: print MAAR configuration during boot Paul Burton 2015-09-22 19:08 ` Paul Burton 2015-09-22 19:08 ` [PATCH 2/2] MIPS: initialise MAARs on secondary CPUs Paul Burton 2015-09-22 19:08 ` Paul Burton 2015-09-24 8:23 ` Markos Chandras 2015-09-24 8:23 ` Markos Chandras
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