From 828f0afda123a96ff4e8078f057a302f4b4232ae Mon Sep 17 00:00:00 2001 From: Don Zickus Date: Tue, 26 Sep 2006 10:52:26 +0200 Subject: [PATCH] x86: Add performance counter reservation framework for UP kernels Adds basic infrastructure to allow subsystems to reserve performance counters on the x86 chips. Only UP kernels are supported in this patch to make reviewing easier. The SMP portion makes a lot more changes. Think of this as a locking mechanism where each bit represents a different counter. In addition, each subsystem should also reserve an appropriate event selection register that will correspond to the performance counter it will be using (this is mainly neccessary for the Pentium 4 chips as they break the 1:1 relationship to performance counters). This will help prevent subsystems like oprofile from interfering with the nmi watchdog. Signed-off-by: Don Zickus Signed-off-by: Andi Kleen --- include/asm-i386/nmi.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/asm-i386/nmi.h') diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h index 67d994799999..27fc9e6f630e 100644 --- a/include/asm-i386/nmi.h +++ b/include/asm-i386/nmi.h @@ -25,6 +25,13 @@ void set_nmi_callback(nmi_callback_t callback); */ void unset_nmi_callback(void); +extern int avail_to_resrv_perfctr_nmi_bit(unsigned int); +extern int avail_to_resrv_perfctr_nmi(unsigned int); +extern int reserve_perfctr_nmi(unsigned int); +extern void release_perfctr_nmi(unsigned int); +extern int reserve_evntsel_nmi(unsigned int); +extern void release_evntsel_nmi(unsigned int); + extern void setup_apic_nmi_watchdog (void); extern int reserve_lapic_nmi(void); extern void release_lapic_nmi(void); -- cgit v1.2.3 From b7471c6da94d30d3deadc55986cc38d1ff57f9ca Mon Sep 17 00:00:00 2001 From: Don Zickus Date: Tue, 26 Sep 2006 10:52:26 +0200 Subject: [PATCH] i386: Add SMP support on i386 to reservation framework This patch includes the changes to make the nmi watchdog on i386 SMP aware. A bunch of code was moved around to make it simpler to read. In addition, it is now possible to determine if a particular NMI was the result of the watchdog or not. This feature allows the kernel to filter out unknown NMIs easier. Signed-off-by: Don Zickus Signed-off-by: Andi Kleen --- include/asm-i386/nmi.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/asm-i386/nmi.h') diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h index 27fc9e6f630e..4cda6801ecb8 100644 --- a/include/asm-i386/nmi.h +++ b/include/asm-i386/nmi.h @@ -32,13 +32,14 @@ extern void release_perfctr_nmi(unsigned int); extern int reserve_evntsel_nmi(unsigned int); extern void release_evntsel_nmi(unsigned int); -extern void setup_apic_nmi_watchdog (void); +extern void setup_apic_nmi_watchdog (void *); extern int reserve_lapic_nmi(void); extern void release_lapic_nmi(void); extern void disable_timer_nmi_watchdog(void); extern void enable_timer_nmi_watchdog(void); -extern void nmi_watchdog_tick (struct pt_regs * regs); +extern void nmi_watchdog_tick (struct pt_regs * regs, unsigned reason); +extern atomic_t nmi_active; extern unsigned int nmi_watchdog; #define NMI_DEFAULT -1 #define NMI_NONE 0 -- cgit v1.2.3 From 3adbbcce9a49b900d4cc118cdccfdefa78bf1afb Mon Sep 17 00:00:00 2001 From: Don Zickus Date: Tue, 26 Sep 2006 10:52:26 +0200 Subject: [PATCH] x86: Cleanup NMI interrupt path This patch cleans up the NMI interrupt path. Instead of being gated by if the 'nmi callback' is set, the interrupt handler now calls everyone who is registered on the die_chain and additionally checks the nmi watchdog, reseting it if enabled. This allows more subsystems to hook into the NMI if they need to (without being block by set_nmi_callback). Signed-off-by: Don Zickus Signed-off-by: Andi Kleen --- include/asm-i386/nmi.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/asm-i386/nmi.h') diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h index 4cda6801ecb8..da0e0b4e9139 100644 --- a/include/asm-i386/nmi.h +++ b/include/asm-i386/nmi.h @@ -37,7 +37,7 @@ extern int reserve_lapic_nmi(void); extern void release_lapic_nmi(void); extern void disable_timer_nmi_watchdog(void); extern void enable_timer_nmi_watchdog(void); -extern void nmi_watchdog_tick (struct pt_regs * regs, unsigned reason); +extern int nmi_watchdog_tick (struct pt_regs * regs, unsigned reason); extern atomic_t nmi_active; extern unsigned int nmi_watchdog; -- cgit v1.2.3 From 2fbe7b25c8edaf2d10e6c1a4cc9f8afe714c4764 Mon Sep 17 00:00:00 2001 From: Don Zickus Date: Tue, 26 Sep 2006 10:52:27 +0200 Subject: [PATCH] i386/x86-64: Remove un/set_nmi_callback and reserve/release_lapic_nmi functions Removes the un/set_nmi_callback and reserve/release_lapic_nmi functions as they are no longer needed. The various subsystems are modified to register with the die_notifier instead. Also includes compile fixes by Andrew Morton. Signed-off-by: Don Zickus Signed-off-by: Andi Kleen --- include/asm-i386/nmi.h | 21 ++++----------------- 1 file changed, 4 insertions(+), 17 deletions(-) (limited to 'include/asm-i386/nmi.h') diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h index da0e0b4e9139..34d6bf063b6e 100644 --- a/include/asm-i386/nmi.h +++ b/include/asm-i386/nmi.h @@ -6,24 +6,13 @@ #include -struct pt_regs; - -typedef int (*nmi_callback_t)(struct pt_regs * regs, int cpu); - -/** - * set_nmi_callback - * - * Set a handler for an NMI. Only one handler may be - * set. Return 1 if the NMI was handled. - */ -void set_nmi_callback(nmi_callback_t callback); - /** - * unset_nmi_callback + * do_nmi_callback * - * Remove the handler previously set. + * Check to see if a callback exists and execute it. Return 1 + * if the handler exists and was handled successfully. */ -void unset_nmi_callback(void); +int do_nmi_callback(struct pt_regs *regs, int cpu); extern int avail_to_resrv_perfctr_nmi_bit(unsigned int); extern int avail_to_resrv_perfctr_nmi(unsigned int); @@ -33,8 +22,6 @@ extern int reserve_evntsel_nmi(unsigned int); extern void release_evntsel_nmi(unsigned int); extern void setup_apic_nmi_watchdog (void *); -extern int reserve_lapic_nmi(void); -extern void release_lapic_nmi(void); extern void disable_timer_nmi_watchdog(void); extern void enable_timer_nmi_watchdog(void); extern int nmi_watchdog_tick (struct pt_regs * regs, unsigned reason); -- cgit v1.2.3 From 407984f1af259b31957c7c05075a454a751bb801 Mon Sep 17 00:00:00 2001 From: Don Zickus Date: Tue, 26 Sep 2006 10:52:27 +0200 Subject: [PATCH] x86: Add abilty to enable/disable nmi watchdog with sysctl Adds a new /proc/sys/kernel/nmi call that will enable/disable the nmi watchdog. Signed-off-by: Don Zickus Signed-off-by: Andi Kleen --- include/asm-i386/nmi.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/asm-i386/nmi.h') diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h index 34d6bf063b6e..13b5d8311bf7 100644 --- a/include/asm-i386/nmi.h +++ b/include/asm-i386/nmi.h @@ -14,6 +14,7 @@ */ int do_nmi_callback(struct pt_regs *regs, int cpu); +extern int nmi_watchdog_enabled; extern int avail_to_resrv_perfctr_nmi_bit(unsigned int); extern int avail_to_resrv_perfctr_nmi(unsigned int); extern int reserve_perfctr_nmi(unsigned int); -- cgit v1.2.3 From 4038f901cf102a40715b900984ed7540a9fa637f Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Tue, 26 Sep 2006 10:52:27 +0200 Subject: [PATCH] i386/x86-64: Fix NMI watchdog suspend/resume Making NMI suspend/resume work with SMP. We use CPU hotplug to offline APs in SMP suspend/resume. Only BSP executes sysdev's .suspend/.resume method. APs should follow CPU hotplug code path. And: +From: Don Zickus Makes the start/stop paths of nmi watchdog more robust to handle the suspend/resume cases more gracefully. AK: I merged the two patches together Signed-off-by: Shaohua Li Signed-off-by: Andi Kleen Cc: Don Zickus Cc: Andi Kleen Signed-off-by: Andrew Morton --- include/asm-i386/nmi.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/asm-i386/nmi.h') diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h index 13b5d8311bf7..303bcd4592bb 100644 --- a/include/asm-i386/nmi.h +++ b/include/asm-i386/nmi.h @@ -23,6 +23,7 @@ extern int reserve_evntsel_nmi(unsigned int); extern void release_evntsel_nmi(unsigned int); extern void setup_apic_nmi_watchdog (void *); +extern void stop_apic_nmi_watchdog (void *); extern void disable_timer_nmi_watchdog(void); extern void enable_timer_nmi_watchdog(void); extern int nmi_watchdog_tick (struct pt_regs * regs, unsigned reason); -- cgit v1.2.3