From 40e2d7f9b5dae048789c64672bf3027fbb663ffa Mon Sep 17 00:00:00 2001 From: Len Brown Date: Wed, 18 Dec 2013 16:44:57 -0500 Subject: x86 idle: Repair large-server 50-watt idle-power regression Linux 3.10 changed the timing of how thread_info->flags is touched: x86: Use generic idle loop (7d1a941731fabf27e5fb6edbebb79fe856edb4e5) This caused Intel NHM-EX and WSM-EX servers to experience a large number of immediate MONITOR/MWAIT break wakeups, which caused cpuidle to demote from deep C-states to shallow C-states, which caused these platforms to experience a significant increase in idle power. Note that this issue was already present before the commit above, however, it wasn't seen often enough to be noticed in power measurements. Here we extend an errata workaround from the Core2 EX "Dunnington" to extend to NHM-EX and WSM-EX, to prevent these immediate returns from MWAIT, reducing idle power on these platforms. While only acpi_idle ran on Dunnington, intel_idle may also run on these two newer systems. As of today, there are no other models that are known to need this tweak. Link: http://lkml.kernel.org/r/CAJvTdK=%2BaNN66mYpCGgbHGCHhYQAKx-vB0kJSWjVpsNb_hOAtQ@mail.gmail.com Signed-off-by: Len Brown Link: http://lkml.kernel.org/r/baff264285f6e585df757d58b17788feabc68918.1387403066.git.len.brown@intel.com Cc: # 3.12.x, 3.11.x, 3.10.x Signed-off-by: H. Peter Anvin --- drivers/idle/intel_idle.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/idle/intel_idle.c') diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 92d1206482a..f80b700f821 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -377,6 +377,9 @@ static int intel_idle(struct cpuidle_device *dev, if (!current_set_polling_and_test()) { + if (this_cpu_has(X86_FEATURE_CLFLUSH_MONITOR)) + clflush((void *)¤t_thread_info()->flags); + __monitor((void *)¤t_thread_info()->flags, 0, 0); smp_mb(); if (!need_resched()) -- cgit v1.2.3-70-g09d2 From ba0dc81ed5d9549daa233d7322b4c2809e28fca8 Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Thu, 9 Jan 2014 15:30:26 +0800 Subject: Revert "intel_idle: mark states tables with __initdata tag" This reverts commit 9d046ccb98085f1d437585f84748c783a04ba240. Commit 9d046ccb98085 marks all state tables with __initdata, but the state table may be accessed when doing CPU online, which then causing system crash as below: [ 204.188841] BUG: unable to handle kernel paging request at ffffffff8227cce8 [ 204.196844] IP: [] intel_idle_cpu_init+0x40/0x130 [ 204.203996] PGD 1e11067 PUD 1e12063 PMD 455859063 PTE 800000000227c062 [ 204.211638] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC [ 204.216975] Modules linked in: x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd gpio_ich microcode joydev sb_edac edac_core ipmi_si lpc_ich ipmi_msghandler lp tpm_tis parport wmi mac_hid acpi_pad hid_generic ixgbe isci usbhid dca hid libsas ptp ahci libahci scsi_transport_sas megaraid_sas pps_core mdio [ 204.262815] CPU: 11 PID: 1489 Comm: bash Not tainted 3.13.0-rc7+ #48 [ 204.269993] Hardware name: Intel Corporation BRICKLAND/BRICKLAND, BIOS BRIVTIN1.86B.0047.L09.1312061514 12/06/2013 [ 204.281646] task: ffff8804303a24a0 ti: ffff880440fac000 task.ti: ffff880440fac000 [ 204.290311] RIP: 0010:[] [] intel_idle_cpu_init+0x40/0x130 [ 204.300184] RSP: 0018:ffff880440fadd28 EFLAGS: 00010286 [ 204.306192] RAX: ffffffff8227cca0 RBX: ffffe8fff1a03400 RCX: 0000000000000007 [ 204.314244] RDX: ffff88045f400000 RSI: 0000000000000009 RDI: 0000000000001120 [ 204.322296] RBP: ffff880440fadd38 R08: 0000000000000000 R09: 0000000000000001 [ 204.330411] R10: 0000000000000001 R11: 0000000000000000 R12: 000000000000001e [ 204.338482] R13: 00000000ffffffdb R14: 0000000000000001 R15: 0000000000000000 [ 204.346743] FS: 00007f64f7b0c740(0000) GS:ffff88045ce00000(0000) knlGS:0000000000000000 [ 204.355919] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 204.362449] CR2: ffffffff8227cce8 CR3: 0000000444ab0000 CR4: 00000000001407e0 [ 204.370520] Stack: [ 204.372853] 000000000000001e ffffffff81f10240 ffff880440fadd50 ffffffff814aa307 [ 204.381519] ffffffff81ea80e0 ffff880440fadda0 ffffffff8185a230 0000000000000000 [ 204.390196] 000000000000001e 0000000000000002 0000000000000002 0000000000000000 [ 204.398856] Call Trace: [ 204.401683] [] cpu_hotplug_notify+0x57/0x70 [ 204.408638] [] notifier_call_chain+0x100/0x150 [ 204.415553] [] __raw_notifier_call_chain+0xe/0x10 [ 204.422772] [] cpu_notify+0x23/0x50 [ 204.428616] [] _cpu_up+0x132/0x1a0 [ 204.434361] [] cpu_up+0x7d/0xa0 [ 204.439819] [] cpu_subsys_online+0x3c/0x90 [ 204.446345] [] device_online+0x45/0xa0 [ 204.452471] [] online_store+0x4e/0x80 [ 204.458511] [] dev_attr_store+0x18/0x30 [ 204.464744] [] sysfs_write_file+0x151/0x1c0 [ 204.471681] [] vfs_write+0xe1/0x160 [ 204.477524] [] SyS_write+0x4c/0x90 [ 204.483270] [] system_call_fastpath+0x1a/0x1f [ 204.490081] Code: 41 54 41 89 fc 8b 3d 48 25 85 01 53 48 8b 1d 30 25 85 01 48 03 1c c5 40 90 fb 81 48 8b 05 19 25 85 01 c7 43 0c 01 00 00 00 66 90 <48> 83 78 48 00 74 4f 41 83 c0 01 41 39 f0 7e 10 48 c7 c7 38 79 [ 204.515723] RIP [] intel_idle_cpu_init+0x40/0x130 [ 204.522996] RSP [ 204.526976] CR2: ffffffff8227cce8 [ 204.530766] ---[ end trace 336f56cc3d1cfc8c ]--- Fixes: 9d046ccb98085 (intel_idle: mark states tables with __initdata tag) Signed-off-by: Jiang Liu Signed-off-by: Rafael J. Wysocki --- drivers/idle/intel_idle.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'drivers/idle/intel_idle.c') diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index f80b700f821..6f456f0f818 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -123,7 +123,7 @@ static struct cpuidle_state *cpuidle_state_table; * which is also the index into the MWAIT hint array. * Thus C0 is a dummy. */ -static struct cpuidle_state nehalem_cstates[] __initdata = { +static struct cpuidle_state nehalem_cstates[] = { { .name = "C1-NHM", .desc = "MWAIT 0x00", @@ -156,7 +156,7 @@ static struct cpuidle_state nehalem_cstates[] __initdata = { .enter = NULL } }; -static struct cpuidle_state snb_cstates[] __initdata = { +static struct cpuidle_state snb_cstates[] = { { .name = "C1-SNB", .desc = "MWAIT 0x00", @@ -196,7 +196,7 @@ static struct cpuidle_state snb_cstates[] __initdata = { .enter = NULL } }; -static struct cpuidle_state ivb_cstates[] __initdata = { +static struct cpuidle_state ivb_cstates[] = { { .name = "C1-IVB", .desc = "MWAIT 0x00", @@ -236,7 +236,7 @@ static struct cpuidle_state ivb_cstates[] __initdata = { .enter = NULL } }; -static struct cpuidle_state hsw_cstates[] __initdata = { +static struct cpuidle_state hsw_cstates[] = { { .name = "C1-HSW", .desc = "MWAIT 0x00", @@ -297,7 +297,7 @@ static struct cpuidle_state hsw_cstates[] __initdata = { .enter = NULL } }; -static struct cpuidle_state atom_cstates[] __initdata = { +static struct cpuidle_state atom_cstates[] = { { .name = "C1E-ATM", .desc = "MWAIT 0x00", -- cgit v1.2.3-70-g09d2 From 88390996c95b879ba365888199b45ace3f5ca80b Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Thu, 9 Jan 2014 15:30:27 +0800 Subject: intel_idle: close avn_cstates array with correct marker Close avn_cstates array with correct marker to avoid overflow in function intel_idle_cpu_init(). [rjw: The problem was introduced when commit 22e580d07f65 was merged on top of eba682a5aeb6 (intel_idle: shrink states tables).] Fixes: 22e580d07f65 (intel_idle: Fixed C6 state on Avoton/Rangeley processors) Signed-off-by: Jiang Liu Signed-off-by: Rafael J. Wysocki --- drivers/idle/intel_idle.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/idle/intel_idle.c') diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 6f456f0f818..797ed29a36e 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -329,7 +329,7 @@ static struct cpuidle_state atom_cstates[] = { { .enter = NULL } }; -static struct cpuidle_state avn_cstates[] __initdata = { +static struct cpuidle_state avn_cstates[] = { { .name = "C1-AVN", .desc = "MWAIT 0x00", @@ -344,6 +344,8 @@ static struct cpuidle_state avn_cstates[] __initdata = { .exit_latency = 15, .target_residency = 45, .enter = &intel_idle }, + { + .enter = NULL } }; /** -- cgit v1.2.3-70-g09d2