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author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2016-11-17 19:35:40 +0100 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2016-11-22 23:34:43 +0100 |
commit | 89666c50472263fba97b7edbfd2a642d1d9d6f74 (patch) | |
tree | 5e78a0954fc497c5ebc09a40ad06485f159f95b1 /arch | |
parent | 08ed487c819d285c3f6ceafd156094102acdfec2 (diff) | |
download | linux-89666c50472263fba97b7edbfd2a642d1d9d6f74.tar.gz linux-89666c50472263fba97b7edbfd2a642d1d9d6f74.tar.bz2 linux-89666c50472263fba97b7edbfd2a642d1d9d6f74.zip |
x86/oprofile/nmi: Convert to hotplug state machine
Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Robert Richter <rric@kernel.org>
Cc: oprofile-list@lists.sf.net
Cc: rt@linuxtronix.de
Link: http://lkml.kernel.org/r/20161117183541.8588-20-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/oprofile/nmi_int.c | 61 |
1 files changed, 18 insertions, 43 deletions
diff --git a/arch/x86/oprofile/nmi_int.c b/arch/x86/oprofile/nmi_int.c index c39172cd6c87..ffdbc4836b4f 100644 --- a/arch/x86/oprofile/nmi_int.c +++ b/arch/x86/oprofile/nmi_int.c @@ -339,10 +339,11 @@ fail: return 0; } -static void nmi_cpu_setup(void *dummy) +static void nmi_cpu_setup(void) { int cpu = smp_processor_id(); struct op_msrs *msrs = &per_cpu(cpu_msrs, cpu); + nmi_cpu_save_registers(msrs); raw_spin_lock(&oprofilefs_lock); model->setup_ctrs(model, msrs); @@ -369,7 +370,7 @@ static void nmi_cpu_restore_registers(struct op_msrs *msrs) } } -static void nmi_cpu_shutdown(void *dummy) +static void nmi_cpu_shutdown(void) { unsigned int v; int cpu = smp_processor_id(); @@ -387,24 +388,26 @@ static void nmi_cpu_shutdown(void *dummy) nmi_cpu_restore_registers(msrs); } -static void nmi_cpu_up(void) +static int nmi_cpu_online(unsigned int cpu) { local_irq_disable(); if (nmi_enabled) - nmi_cpu_setup(NULL); + nmi_cpu_setup(); if (ctr_running) nmi_cpu_start(NULL); local_irq_enable(); + return 0; } -static void nmi_cpu_down(void) +static int nmi_cpu_down_prep(unsigned int cpu) { local_irq_disable(); if (ctr_running) nmi_cpu_stop(NULL); if (nmi_enabled) - nmi_cpu_shutdown(NULL); + nmi_cpu_shutdown(); local_irq_enable(); + return 0; } static int nmi_create_files(struct dentry *root) @@ -437,24 +440,7 @@ static int nmi_create_files(struct dentry *root) return 0; } -static int oprofile_cpu_notifier(struct notifier_block *b, unsigned long action, - void *data) -{ - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_DOWN_FAILED: - case CPU_ONLINE: - nmi_cpu_up(); - break; - case CPU_DOWN_PREPARE: - nmi_cpu_down(); - break; - } - return NOTIFY_DONE; -} - -static struct notifier_block oprofile_cpu_nb = { - .notifier_call = oprofile_cpu_notifier -}; +static enum cpuhp_state cpuhp_nmi_online; static int nmi_setup(void) { @@ -497,20 +483,17 @@ static int nmi_setup(void) if (err) goto fail; - cpu_notifier_register_begin(); - - /* Use get/put_online_cpus() to protect 'nmi_enabled' */ - get_online_cpus(); nmi_enabled = 1; /* make nmi_enabled visible to the nmi handler: */ smp_mb(); - on_each_cpu(nmi_cpu_setup, NULL, 1); - __register_cpu_notifier(&oprofile_cpu_nb); - put_online_cpus(); - - cpu_notifier_register_done(); - + err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/oprofile:online", + nmi_cpu_online, nmi_cpu_down_prep); + if (err < 0) + goto fail_nmi; + cpuhp_nmi_online = err; return 0; +fail_nmi: + unregister_nmi_handler(NMI_LOCAL, "oprofile"); fail: free_msrs(); return err; @@ -520,17 +503,9 @@ static void nmi_shutdown(void) { struct op_msrs *msrs; - cpu_notifier_register_begin(); - - /* Use get/put_online_cpus() to protect 'nmi_enabled' & 'ctr_running' */ - get_online_cpus(); - on_each_cpu(nmi_cpu_shutdown, NULL, 1); + cpuhp_remove_state(cpuhp_nmi_online); nmi_enabled = 0; ctr_running = 0; - __unregister_cpu_notifier(&oprofile_cpu_nb); - put_online_cpus(); - - cpu_notifier_register_done(); /* make variables visible to the nmi handler: */ smp_mb(); |