From 7fb06fc9672b947424e05871243a4c8e19ec3bce Mon Sep 17 00:00:00 2001 From: Hidetoshi Seto Date: Mon, 15 Jun 2009 18:18:43 +0900 Subject: x86, mce: cleanup mce_start() Simplify interface of mce_start(): - no_way_out = mce_start(no_way_out, &order); + order = mce_start(&no_way_out); Now Monarch and Subjects share same exit(return) in usual path. Signed-off-by: Hidetoshi Seto Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/mcheck/mce.c | 66 +++++++++++++++++++--------------------- 1 file changed, 31 insertions(+), 35 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index dda77215e9e..739fd7eca0a 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -691,23 +691,21 @@ static atomic_t global_nwo; * in the entry order. * TBD double check parallel CPU hotunplug */ -static int mce_start(int no_way_out, int *order) +static int mce_start(int *no_way_out) { - int nwo; + int order; int cpus = num_online_cpus(); u64 timeout = (u64)monarch_timeout * NSEC_PER_USEC; - if (!timeout) { - *order = -1; - return no_way_out; - } + if (!timeout) + return -1; - atomic_add(no_way_out, &global_nwo); + atomic_add(*no_way_out, &global_nwo); /* * global_nwo should be updated before mce_callin */ smp_wmb(); - *order = atomic_add_return(1, &mce_callin); + order = atomic_add_return(1, &mce_callin); /* * Wait for everyone. @@ -715,8 +713,7 @@ static int mce_start(int no_way_out, int *order) while (atomic_read(&mce_callin) != cpus) { if (mce_timed_out(&timeout)) { atomic_set(&global_nwo, 0); - *order = -1; - return no_way_out; + return -1; } ndelay(SPINUNIT); } @@ -725,34 +722,34 @@ static int mce_start(int no_way_out, int *order) * mce_callin should be read before global_nwo */ smp_rmb(); - /* - * Cache the global no_way_out state. - */ - nwo = atomic_read(&global_nwo); - /* - * Monarch starts executing now, the others wait. - */ - if (*order == 1) { + if (order == 1) { + /* + * Monarch: Starts executing now, the others wait. + */ atomic_set(&mce_executing, 1); - return nwo; + } else { + /* + * Subject: Now start the scanning loop one by one in + * the original callin order. + * This way when there are any shared banks it will be + * only seen by one CPU before cleared, avoiding duplicates. + */ + while (atomic_read(&mce_executing) < order) { + if (mce_timed_out(&timeout)) { + atomic_set(&global_nwo, 0); + return -1; + } + ndelay(SPINUNIT); + } } /* - * Now start the scanning loop one by one - * in the original callin order. - * This way when there are any shared banks it will - * be only seen by one CPU before cleared, avoiding duplicates. + * Cache the global no_way_out state. */ - while (atomic_read(&mce_executing) < *order) { - if (mce_timed_out(&timeout)) { - atomic_set(&global_nwo, 0); - *order = -1; - return no_way_out; - } - ndelay(SPINUNIT); - } - return nwo; + *no_way_out = atomic_read(&global_nwo); + + return order; } /* @@ -871,8 +868,7 @@ void do_machine_check(struct pt_regs *regs, long error_code) * Establish sequential order between the CPUs entering the machine * check handler. */ - int order = -1; - + int order; /* * If no_way_out gets set, there is no safe way to recover from this * MCE. If tolerant is cranked up, we'll try anyway. @@ -917,7 +913,7 @@ void do_machine_check(struct pt_regs *regs, long error_code) * This way we don't report duplicated events on shared banks * because the first one to see it will clear it. */ - no_way_out = mce_start(no_way_out, &order); + order = mce_start(&no_way_out); for (i = 0; i < banks; i++) { __clear_bit(i, toclear); if (!bank[i]) -- cgit v1.2.3