From ddb4f0df0424d174567a011a176782ffa4202071 Mon Sep 17 00:00:00 2001 From: Hidetoshi Seto Date: Tue, 26 Sep 2006 15:27:56 -0700 Subject: [IA64] CMC/CPE: Reverse the order of fetching log and checking poll threshold This patch reverses the order of fetching log from SAL and checking poll threshold. This will fix following trivial issues: - If SAL_GET_SATE_INFO is unbelievably slow (due to huge system or just its silly implementation) and if it takes more than 1/5 sec, CMCI/CPEI will never switch to CMCP/CPEP. - Assuming terrible flood of interrupt (continuous corrected errors let all CPUs enter to handler at once and bind them in it), CPUs will be serialized by IA64_LOG_LOCK(*). Now we check the poll threshold after the lock and log fetch, so we need to call SAL_GET_STATE_INFO (num_online_cpus() + 4) times in the worst case. if we can check the threshold before the lock, we can shut up interrupts quickly without waiting preceding log fetches, and the number of times will be reduced to (num_online_cpus()) in the same situation. Signed-off-by: Hidetoshi Seto Signed-off-by: Tony Luck --- arch/ia64/kernel/mca.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) (limited to 'arch/ia64') diff --git a/arch/ia64/kernel/mca.c b/arch/ia64/kernel/mca.c index 98f3b26d7aff..bfbd8986153b 100644 --- a/arch/ia64/kernel/mca.c +++ b/arch/ia64/kernel/mca.c @@ -511,9 +511,6 @@ ia64_mca_cpe_int_handler (int cpe_irq, void *arg, struct pt_regs *ptregs) /* SAL spec states this should run w/ interrupts enabled */ local_irq_enable(); - /* Get the CPE error record and log it */ - ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CPE); - spin_lock(&cpe_history_lock); if (!cpe_poll_enabled && cpe_vector >= 0) { @@ -542,7 +539,7 @@ ia64_mca_cpe_int_handler (int cpe_irq, void *arg, struct pt_regs *ptregs) mod_timer(&cpe_poll_timer, jiffies + MIN_CPE_POLL_INTERVAL); /* lock already released, get out now */ - return IRQ_HANDLED; + goto out; } else { cpe_history[index++] = now; if (index == CPE_HISTORY_LENGTH) @@ -550,6 +547,10 @@ ia64_mca_cpe_int_handler (int cpe_irq, void *arg, struct pt_regs *ptregs) } } spin_unlock(&cpe_history_lock); +out: + /* Get the CPE error record and log it */ + ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CPE); + return IRQ_HANDLED; } @@ -1278,9 +1279,6 @@ ia64_mca_cmc_int_handler(int cmc_irq, void *arg, struct pt_regs *ptregs) /* SAL spec states this should run w/ interrupts enabled */ local_irq_enable(); - /* Get the CMC error record and log it */ - ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CMC); - spin_lock(&cmc_history_lock); if (!cmc_polling_enabled) { int i, count = 1; /* we know 1 happened now */ @@ -1313,7 +1311,7 @@ ia64_mca_cmc_int_handler(int cmc_irq, void *arg, struct pt_regs *ptregs) mod_timer(&cmc_poll_timer, jiffies + CMC_POLL_INTERVAL); /* lock already released, get out now */ - return IRQ_HANDLED; + goto out; } else { cmc_history[index++] = now; if (index == CMC_HISTORY_LENGTH) @@ -1321,6 +1319,10 @@ ia64_mca_cmc_int_handler(int cmc_irq, void *arg, struct pt_regs *ptregs) } } spin_unlock(&cmc_history_lock); +out: + /* Get the CMC error record and log it */ + ia64_mca_log_sal_error_record(SAL_INFO_TYPE_CMC); + return IRQ_HANDLED; } -- cgit v1.2.2