Messages in this thread Patch in this message | | | From | Sergei Shtylyov <> | Subject | [PATCH] 2.6.18-rt7: fix more issues with 32-bit cycles_t in latency_trace.c | Date | Mon, 13 Nov 2006 00:23:12 +0300 |
| |
In addition to clock wrap check being falsely triggered with 32-bit cycles_t, as noticed to Kevin Hilman, there's another issue: using %Lx format to print 32-bit values warrants erroneous values on 32-bit machines like ARM and PPC32.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
--- PPC32 actually has 64-bit timebase counter, so could provide for 64-bit cycles_t -- maybe it's worth to rewrite get_cycles() to read both lower and upper registers?
Index: linux-2.6/kernel/latency_trace.c =================================================================== --- linux-2.6.orig/kernel/latency_trace.c +++ linux-2.6/kernel/latency_trace.c @@ -1623,8 +1623,8 @@ check_critical_timing(int cpu, struct cp #ifndef CONFIG_CRITICAL_LATENCY_HIST if (!preempt_thresh && preempt_max_latency > delta) { printk("bug: updating %016Lx > %016Lx?\n", - preempt_max_latency, delta); - printk(" [%016Lx %016Lx %016Lx]\n", T0, T1, T2); + (u64)preempt_max_latency, (u64)delta); + printk(" [%016Lx %016Lx %016Lx]\n", (u64)T0, (u64)T1, (u64)T2); } #endif - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |