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author | travis@sgi.com <travis@sgi.com> | 2017-01-25 19:35:20 +0300 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2017-02-01 12:20:59 +0300 |
commit | 278c9b099b2fc0cc0a51de95a1dcefcf54ca2183 (patch) | |
tree | 37e3c170f634af410dda484bb38aac36a1c0931d | |
parent | abdf1df6bc0416ec19b841e92b497ca55b23454c (diff) | |
download | linux-278c9b099b2fc0cc0a51de95a1dcefcf54ca2183.tar.xz |
x86/platform/UV: Add basic CPU NMI health check
Add a low impact health check triggered by the system NMI command
that essentially checks which CPUs are responding to external NMI's.
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Russ Anderson <rja@hpe.com>
Reviewed-by: Alex Thorlton <athorlton@sgi.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Dimitri Sivanich <sivanich@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170125163517.756690240@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-rw-r--r-- | arch/x86/platform/uv/uv_nmi.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/arch/x86/platform/uv/uv_nmi.c b/arch/x86/platform/uv/uv_nmi.c index df7b092941fe..8a4aa5b3c11a 100644 --- a/arch/x86/platform/uv/uv_nmi.c +++ b/arch/x86/platform/uv/uv_nmi.c @@ -176,6 +176,7 @@ module_param_named(debug, uv_nmi_debug, int, 0644); * "kdump" - do crash dump * "kdb" - enter KDB (default) * "kgdb" - enter KGDB + * "health" - check if CPUs respond to NMI */ static char uv_nmi_action[8] = "kdb"; module_param_string(action, uv_nmi_action, sizeof(uv_nmi_action), 0644); @@ -571,6 +572,22 @@ static void uv_nmi_sync_exit(int master) } } +/* Current "health" check is to check which CPU's are responsive */ +static void uv_nmi_action_health(int cpu, struct pt_regs *regs, int master) +{ + if (master) { + int in = atomic_read(&uv_nmi_cpus_in_nmi); + int out = num_online_cpus() - in; + + pr_alert("UV: NMI CPU health check (non-responding:%d)\n", out); + atomic_set(&uv_nmi_slave_continue, SLAVE_EXIT); + } else { + while (!atomic_read(&uv_nmi_slave_continue)) + cpu_relax(); + } + uv_nmi_sync_exit(master); +} + /* Walk through cpu list and dump state of each */ static void uv_nmi_dump_state(int cpu, struct pt_regs *regs, int master) { @@ -747,7 +764,9 @@ int uv_handle_nmi(unsigned int reason, struct pt_regs *regs) uv_nmi_wait(master); /* Process actions other than "kdump": */ - if (uv_nmi_action_is("ips") || uv_nmi_action_is("dump")) { + if (uv_nmi_action_is("health")) { + uv_nmi_action_health(cpu, regs, master); + } else if (uv_nmi_action_is("ips") || uv_nmi_action_is("dump")) { uv_nmi_dump_state(cpu, regs, master); } else if (uv_nmi_action_is("kdb") || uv_nmi_action_is("kgdb")) { uv_call_kgdb_kdb(cpu, regs, master); |