Re: [PATCH v3 0/9] kexec_file_load implementation for PowerPC

Hello Balbir, Am Mittwoch, 22 Juni 2016, 23:29:46 schrieb Balbir Singh: > On Tue, 21 Jun 2016 16:48:32 -0300 > Thiago Jung Bauermann wrote: > > This patch series implements the kexec_file_load system call on > > PowerPC. > > > > This system call moves the reading of

Re: [PATCHv2 1/7] ppc bpf/jit: Disable classic BPF JIT on ppc64le

On Wed, Jun 22, 2016 at 09:55:01PM +0530, Naveen N. Rao wrote: > Classic BPF JIT was never ported completely to work on little endian > powerpc. However, it can be enabled and will crash the system when used. > As such, disable use of BPF JIT on ppc64le. Thanks, Naveen. Acked-by: Thadeu Lima de

Re: [PATCH 0/6] kexec_file: Add buffer hand-over for the next kernel

Hi Dave, On Wed, 2016-06-22 at 09:20 +0800, Dave Young wrote: > On 06/20/16 at 10:44pm, Thiago Jung Bauermann wrote: > > Hello, > > > > This patch series implements a mechanism which allows the kernel to pass on > > a buffer to the kernel that will be kexec'd. This buffer is passed as a > >

Re: [PATCH v13 01/16] PCI: Let pci_mmap_page_range() take resource address

On Tue, Jun 21, 2016 at 09:32:49PM -0700, Yinghai Lu wrote: > On Sat, Jun 18, 2016 at 5:17 AM, Bjorn Helgaas wrote: > > On Fri, Jun 17, 2016 at 07:24:46PM -0700, Yinghai Lu wrote: > >> In 8c05cd08a7 ("PCI: fix offset check for sysfs mmapped files"), try > >> to check exposed

Re: [PATCH] ppc: Fix BPF JIT for ABIv2

On 2016/06/22 12:42PM, Naveen N Rao wrote: > On 2016/06/21 11:47AM, Thadeu Lima de Souza Cascardo wrote: > > On Tue, Jun 21, 2016 at 09:15:48PM +1000, Michael Ellerman wrote: > > > On Tue, 2016-06-21 at 14:28 +0530, Naveen N. Rao wrote: > > > > On 2016/06/20 03:56PM, Thadeu Lima de Souza Cascardo

cpuidle broken on mainline

Hi, I was noticing some pretty big run to run variations on single threaded benchmarks, and I've isolated it cpuidle issues. If I look at the cpuidle tracepoint, I notice we only go into the snooze state. Do we have any known bugs in cpuidle at the moment? While looking around, I also noticed

Re: [RFC PATCH v2 05/18] sched: add task flag for preempt IRQ tracking

On Wed, Jun 22, 2016 at 9:30 AM, Josh Poimboeuf wrote: > On Mon, May 23, 2016 at 08:52:12PM -0700, Andy Lutomirski wrote: >> On May 23, 2016 7:28 PM, "Josh Poimboeuf" wrote: >> > > Maybe I'm coming around to liking this idea. >> > >> > Ok, good :-) >> >

Re: [PATCH] ppc: Fix BPF JIT for ABIv2

On 2016/06/21 11:47AM, Thadeu Lima de Souza Cascardo wrote: > On Tue, Jun 21, 2016 at 09:15:48PM +1000, Michael Ellerman wrote: > > On Tue, 2016-06-21 at 14:28 +0530, Naveen N. Rao wrote: > > > On 2016/06/20 03:56PM, Thadeu Lima de Souza Cascardo wrote: > > > > On Sun, Jun 19, 2016 at 11:19:14PM

Re: [6/6] ppc: ebpf/jit: Implement JIT compiler for extended BPF

On 2016/06/21 09:04PM, Michael Ellerman wrote: > On Tue, 2016-06-21 at 12:28 +0530, Naveen N. Rao wrote: > > On 2016/06/21 09:38AM, Michael Ellerman wrote: > > > On Sun, 2016-06-19 at 23:06 +0530, Naveen N. Rao wrote: > > > > > > > > #include > > > > > > > > in bpf_jit_comp64.c > > > > > > > >

Re: [PATCH v3] tools/perf: Fix the mask in regs_dump__printf and print_sample_iregs

On Tue, Jun 21, 2016 at 06:35:31PM +0300, Yury Norov wrote: SNIP > > index 5214974e841a..1337b1c73f82 100644 > > --- a/tools/perf/util/session.c > > +++ b/tools/perf/util/session.c > > @@ -940,8 +940,22 @@ static void branch_stack__printf(struct perf_sample > > *sample) > > static void

Re: [PATCH v3 3/9] kexec_file: Factor out kexec_locate_mem_hole from kexec_add_buffer.

On 06/21/16 at 04:48pm, Thiago Jung Bauermann wrote: > kexec_locate_mem_hole will be used by the PowerPC kexec_file_load > implementation to find free memory for the purgatory stack. > > Signed-off-by: Thiago Jung Bauermann > Cc: Eric Biederman

[PATCH 3/3] powerpc/pnv/pci: Fix incorrect PE reservation attempt on some 64-bit BARs

The generic allocation code may sometimes decide to assign a prefetchable 64-bit BAR to the M32 window. In fact it may also decide to allocate a 64-bit non-prefetchable BAR to the M64 one ! So using the resource flags as a test to decide which window was used for PE allocation is just wrong and

Re: [PATCH v3 2/9] kexec_file: Generalize kexec_add_buffer.

The patch looks good, but could the subject be more specific? For example just like the first sentence of the patch descriotion: Allow architectures to specify their own memory walking function On 06/21/16 at 04:48pm, Thiago Jung Bauermann wrote: > Allow architectures to specify different

Re: [PATCH 3/3] powerpc/pnv/pci: Fix incorrect PE reservation attempt on some 64-bit BARs

On Wed, Jun 22, 2016 at 05:26:19PM +1000, Benjamin Herrenschmidt wrote: >The generic allocation code may sometimes decide to assign a prefetchable >64-bit BAR to the M32 window. In fact it may also decide to allocate >a 64-bit non-prefetchable BAR to the M64 one ! So using the resource >flags as a

[RFC/PATCH] powerpc/pci: Don't try to allocate resources that will be reassigned

When we know we will reassign all resources, trying (and failing) to allocate them initially is fairly pointless and leads to a lot of scary messages in the kernel log Signed-off-by: Benjamin Herrenschmidt -- This one probably needs testing on a few platforms but I

[PATCH] powerpc/pci: Reduce log level of PCI I/O space warning

If a PHB has no I/O space, there's no need to make it look like something bad happened, a pr_debug() is plenty enough since this is the case of all our modern POWER chips. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/pci-common.c | 6 +++--- 1 file

Re: [PATCH 6/6] ppc: ebpf/jit: Implement JIT compiler for extended BPF

On Tue, 2016-06-07 at 19:02 +0530, Naveen N. Rao wrote: > PPC64 eBPF JIT compiler. > > Enable with: > echo 1 > /proc/sys/net/core/bpf_jit_enable > or > echo 2 > /proc/sys/net/core/bpf_jit_enable > > ... to see the generated JIT code. This can further be processed with >

Re: [PATCH 2/2] KVM: PPC: hypervisor large decrementer support

On Wed, Jun 1, 2016 at 4:23 PM, Michael Neuling wrote: > On Tue, 2016-05-31 at 17:16 +1000, Oliver O'Halloran wrote: >> +#define IS_LD_ENABLED(reg) \ >> + mfspr reg,SPRN_LPCR; \ >> + andis. reg,reg,(LPCR_LD >> 16); > > FWIW you can use: >

Kernel 4.7 doesn't boot with the commit "powerpc-4.7-1" on the Nemo board

Hi All, We have a patch where is the problematic code. One question. Which file is responsible for starting the kernel in this patch? Maybe more than one file. We know that the kernel doesn't start. It must be a source code for the early startup. I was able to compile the RC4 without the

Re: [PATCH 3/3] powerpc/pnv/pci: Fix incorrect PE reservation attempt on some 64-bit BARs

On Wed, 2016-06-22 at 20:32 +1000, Gavin Shan wrote: > In pci_read_bridge_mmio_pref(), no prefetchable window (64bits+pref) > is populated if bit PCI_PREF_RANGE_TYPE_64 (0x1) isn't set on PCI > config register (PCI_PREF_MEMORY_BASE, 0x24). During the resource > resizing and assigning stage in PCI

Re: [PATCH 6/6] ppc: ebpf/jit: Implement JIT compiler for extended BPF

On 2016/06/22 08:37PM, Michael Ellerman wrote: > On Tue, 2016-06-07 at 19:02 +0530, Naveen N. Rao wrote: > > > PPC64 eBPF JIT compiler. > > > > Enable with: > > echo 1 > /proc/sys/net/core/bpf_jit_enable > > or > > echo 2 > /proc/sys/net/core/bpf_jit_enable > > > > ... to see the generated JIT

Re: [PATCH v3] tools/perf: Fix the mask in regs_dump__printf and print_sample_iregs

On Wed, Jun 22, 2016 at 09:20:43AM +0530, Madhavan Srinivasan wrote: > > > On Tuesday 21 June 2016 09:05 PM, Yury Norov wrote: > > On Tue, Jun 21, 2016 at 08:26:40PM +0530, Madhavan Srinivasan wrote: > >> When decoding the perf_regs mask in regs_dump__printf(), > >> we loop through the mask

Re: [PATCH v3 0/9] kexec_file_load implementation for PowerPC

On Tue, 21 Jun 2016 16:48:32 -0300 Thiago Jung Bauermann wrote: > Hello, > > This patch series implements the kexec_file_load system call on > PowerPC. > > This system call moves the reading of the kernel, initrd and the > device tree from the userspace kexec tool

Re: [v6, 1/2] cxl: Add mechanism for delivering AFU driver specific events

Matthew R. Ochs wrote: On Jun 21, 2016, at 5:34 AM, Vaibhav Jain wrote: Hi Ian, Ian Munsie writes: Excerpts from Vaibhav Jain's message of 2016-06-20 14:20:16 +0530: What exactly is the use case for this API? I'd vote to drop it if we can

Re: [v6, 1/2] cxl: Add mechanism for delivering AFU driver specific events

Should also check against the length of user-buffer (count) provided in the read call.Ideally this condition check should be moved to the read call where you have access to the count variable. Right now libcxl is using a harcoded value of CXL_READ_MIN_SIZE to issue the read call and in kernel

Re: [RFC PATCH v2 05/18] sched: add task flag for preempt IRQ tracking

On Wed, Jun 22, 2016 at 11:26:21AM -0700, Andy Lutomirski wrote: > On Wed, Jun 22, 2016 at 11:22 AM, Josh Poimboeuf wrote: > > On Wed, Jun 22, 2016 at 10:59:23AM -0700, Andy Lutomirski wrote: > >> > So I got a chance to look at this some more. I'm thinking that to make > >>

Kernel 4.7: PAGE_GUARDED and _PAGE_NO_CACHE

Hi All, Please find attached Darren's patch. With this patch, the Nemo board boots. That means, the problematic source code is somewhere in this patch. Which file in this patch is responsible for starting the kernel? Thanks, Christian On 13 June 2016 at 8:09 PM, Christian Zigotzky wrote: > Hi

Re: [RFC PATCH v2 05/18] sched: add task flag for preempt IRQ tracking

On Wed, Jun 22, 2016 at 10:59:23AM -0700, Andy Lutomirski wrote: > > So I got a chance to look at this some more. I'm thinking that to make > > this feature more consistently useful, we shouldn't only annotate > > pt_regs frames for calls to handlers; other calls should be annotated as > > well:

Re: [RFC PATCH v2 05/18] sched: add task flag for preempt IRQ tracking

On Wed, Jun 22, 2016 at 11:22 AM, Josh Poimboeuf wrote: > On Wed, Jun 22, 2016 at 10:59:23AM -0700, Andy Lutomirski wrote: >> > So I got a chance to look at this some more. I'm thinking that to make >> > this feature more consistently useful, we shouldn't only annotate >> >

[PATCHv2 0/7] eBPF JIT for PPC64

v2 changes: - Patch 1 is new and is cc'ed -stable - Patch 7 has 3 changes: - Include asm/kprobes.h to resolve a build error reported by Michael Ellerman - Remove check for fp in bpf_int_jit_compile() as suggested by Daniel Borkmann - Fix a crash on Cell processor reported

[PATCHv2 6/7] ppc: bpf/jit: Isolate classic BPF JIT specifics into a separate header

Break out classic BPF JIT specifics into a separate header in preparation for eBPF JIT implementation. Note that ppc32 will still need the classic BPF JIT. Cc: Matt Evans Cc: Denis Kirjanov Cc: Michael Ellerman Cc: Paul Mackerras

[PATCHv2 7/7] ppc: ebpf/jit: Implement JIT compiler for extended BPF

PPC64 eBPF JIT compiler. Enable with: echo 1 > /proc/sys/net/core/bpf_jit_enable or echo 2 > /proc/sys/net/core/bpf_jit_enable ... to see the generated JIT code. This can further be processed with tools/net/bpf_jit_disasm. With CONFIG_TEST_BPF=m and 'modprobe test_bpf': test_bpf: Summary: 305

[PATCHv2 3/7] ppc: bpf/jit: Optimize 64-bit Immediate loads

Similar to the LI32() optimization, if the value can be represented in 32-bits, use LI32(). Also handle loading a few specific forms of immediate values in an optimum manner. Cc: Matt Evans Cc: Denis Kirjanov Cc: Michael Ellerman

[PATCHv2 2/7] ppc: bpf/jit: Fix/enhance 32-bit Load Immediate implementation

The existing LI32() macro can sometimes result in a sign-extended 32-bit load that does not clear the top 32-bits properly. As an example, loading 0x7fff results in the register containing 0x7fff. While this does not impact classic BPF JIT implementation (since that only uses the

[PATCHv2 5/7] ppc: bpf/jit: A few cleanups

1. Per the ISA, ADDIS actually uses RT, rather than RS. Though the result is the same, make the usage clear. 2. The multiply instruction used is a 32-bit multiply. Rename PPC_MUL() to PPC_MULW() to make the same clear. 3. PPC_STW[U] take the entire 16-bit immediate value and do not require

[PATCHv2 1/7] ppc bpf/jit: Disable classic BPF JIT on ppc64le

Classic BPF JIT was never ported completely to work on little endian powerpc. However, it can be enabled and will crash the system when used. As such, disable use of BPF JIT on ppc64le. Cc: sta...@vger.kernel.org Cc: Matt Evans Cc: Denis Kirjanov Cc:

[PATCHv2 4/7] ppc: bpf/jit: Introduce rotate immediate instructions

Since we will be using the rotate immediate instructions for extended BPF JIT, let's introduce macros for the same. And since the shift immediate operations use the rotate immediate instructions, let's redo those macros to use the newly introduced instructions. Cc: Matt Evans

Re: [RFC PATCH v2 05/18] sched: add task flag for preempt IRQ tracking

On Mon, May 23, 2016 at 08:52:12PM -0700, Andy Lutomirski wrote: > On May 23, 2016 7:28 PM, "Josh Poimboeuf" wrote: > > > Maybe I'm coming around to liking this idea. > > > > Ok, good :-) > > > > > In an ideal world (DWARF support, high-quality unwinder, nice pretty > > >

Re: [PATCH 0/6] kexec_file: Add buffer hand-over for the next kernel

Hello Dave, Thanks for your considerations on this feature. Am Mittwoch, 22 Juni 2016, 09:20:46 schrieb Dave Young: > On 06/20/16 at 10:44pm, Thiago Jung Bauermann wrote: > > This feature was implemented because the Integrity Measurement > > Architecture subsystem needs to preserve its

Re: [PATCH v4] tools/perf: Fix the mask in regs_dump__printf and print_sample_iregs

On Thursday 23 June 2016 10:48 AM, Yury Norov wrote: > On Thu, Jun 23, 2016 at 10:31:16AM +0530, Madhavan Srinivasan wrote: >> When decoding the perf_regs mask in regs_dump__printf(), >> we loop through the mask using find_first_bit and find_next_bit functions. >> "mask" is of type "u64", but

Re: [PATCH v3 3/9] kexec_file: Factor out kexec_locate_mem_hole from kexec_add_buffer.

- Original Message - From: "Dave Young" To: "Thiago Jung Bauermann" Cc: linuxppc-dev@lists.ozlabs.org, ke...@lists.infradead.org, linux-ker...@vger.kernel.org, "Eric Biederman" Sent: Thursday, June 23, 2016

Re: [PATCH] cpuidle/powernv: Fix snooze timeout

On 23/06/16 05:36, Shreyas B. Prabhu wrote: > Snooze is a poll idle state in powernv and pseries platforms. Snooze > has a timeout so that if a cpu stays in snooze for more than target > residency of the next available idle state, then it would exit thereby > giving chance to the cpuidle

Re: [PATCH v3 2/9] kexec_file: Generalize kexec_add_buffer.

Am Mittwoch, 22 Juni 2016, 18:20:47 schrieb Dave Young: > The patch looks good, but could the subject be more specific? > > For example just like the first sentence of the patch descriotion: > Allow architectures to specify their own memory walking function Ok, What about this? I also changed

Re: [RFC PATCH v2 05/18] sched: add task flag for preempt IRQ tracking

On Wed, Jun 22, 2016 at 9:30 AM, Josh Poimboeuf wrote: > Andy, > > So I got a chance to look at this some more. I'm thinking that to make > this feature more consistently useful, we shouldn't only annotate > pt_regs frames for calls to handlers; other calls should be

Re: [PATCH v4] tools/perf: Fix the mask in regs_dump__printf and print_sample_iregs

On Thu, Jun 23, 2016 at 10:31:16AM +0530, Madhavan Srinivasan wrote: > When decoding the perf_regs mask in regs_dump__printf(), > we loop through the mask using find_first_bit and find_next_bit functions. > "mask" is of type "u64", but sent as a "unsigned long *" to > lib functions along with

[PATCH v5] tools/perf: Fix the mask in regs_dump__printf and print_sample_iregs

When decoding the perf_regs mask in regs_dump__printf(), we loop through the mask using find_first_bit and find_next_bit functions. "mask" is of type "u64", but sent as a "unsigned long *" to lib functions along with sizeof(). While the exisitng code works fine in most of the case, the logic is

Re: [PATCH v3 3/9] kexec_file: Factor out kexec_locate_mem_hole from kexec_add_buffer.

Am Mittwoch, 22 Juni 2016, 18:18:01 schrieb Dave Young: > On 06/21/16 at 04:48pm, Thiago Jung Bauermann wrote: > > +/** > > + * kexec_locate_mem_hole - find free memory to load segment or use in > > purgatory + * @image: kexec image being updated. > > + * @size: Memory size. > > + * @align:

Re: [PATCH] cpuidle/powernv: Fix snooze timeout

On Wed, Jun 22, 2016 at 9:36 PM, Shreyas B. Prabhu wrote: > Snooze is a poll idle state in powernv and pseries platforms. Snooze > has a timeout so that if a cpu stays in snooze for more than target > residency of the next available idle state, then it would exit

Re: [PATCH v3 0/9] kexec_file_load implementation for PowerPC

On 23/06/16 03:02, Thiago Jung Bauermann wrote: > Hello Balbir, > Hi Thiago >>> 3. have IMA pass-on its event log (where integrity measurements are >>> >>>registered) accross kexec to the second kernel, so that the event >>>history is preserved. >> >> OK.. and this is safe? Do both the

Re: [PATCH v3 3/9] kexec_file: Factor out kexec_locate_mem_hole from kexec_add_buffer.

On 06/22/16 at 08:34pm, Thiago Jung Bauermann wrote: > Am Mittwoch, 22 Juni 2016, 18:18:01 schrieb Dave Young: > > On 06/21/16 at 04:48pm, Thiago Jung Bauermann wrote: > > > +/** > > > + * kexec_locate_mem_hole - find free memory to load segment or use in > > > purgatory + * @image: kexec

Re: [PATCH v3 2/9] kexec_file: Generalize kexec_add_buffer.

On 06/22/16 at 08:30pm, Thiago Jung Bauermann wrote: > Am Mittwoch, 22 Juni 2016, 18:20:47 schrieb Dave Young: > > The patch looks good, but could the subject be more specific? > > > > For example just like the first sentence of the patch descriotion: > > Allow architectures to specify their own

Re: [PATCH v10 13/18] powerpc/pci: Delay populating pdn

On Thu, Jun 23, 2016 at 10:59:57AM +1000, Daniel Axtens wrote: >Hi, > >mpe merged this to his next yesterday, and my nightly scripts picked up >the following cppcheck warning: > >[arch/powerpc/kernel/pci_dn.c:486]: (error) Memory leak: pdn > >That goes to the following function: > >static void

Re: [PATCH] cpuidle/powernv: Fix snooze timeout

On 06/23/2016 05:18 AM, Balbir Singh wrote: > > > On 23/06/16 05:36, Shreyas B. Prabhu wrote: >> Snooze is a poll idle state in powernv and pseries platforms. Snooze >> has a timeout so that if a cpu stays in snooze for more than target >> residency of the next available idle state, then it

Re: [PATCH v10 13/18] powerpc/pci: Delay populating pdn

Hi, mpe merged this to his next yesterday, and my nightly scripts picked up the following cppcheck warning: [arch/powerpc/kernel/pci_dn.c:486]: (error) Memory leak: pdn That goes to the following function: static void *add_pdn(struct device_node *dn, void *data) { struct pci_controller

[PATCH v4] tools/perf: Fix the mask in regs_dump__printf and print_sample_iregs

When decoding the perf_regs mask in regs_dump__printf(), we loop through the mask using find_first_bit and find_next_bit functions. "mask" is of type "u64", but sent as a "unsigned long *" to lib functions along with sizeof(). While the exisitng code works fine in most of the case, the logic is

RE: [PATCH 2/4] soc: fsl: add GUTS driver for QorIQ platforms

Hi Arnd, Could you comment on these? Thanks. Best regards, Yangbo Lu > -Original Message- > From: Scott Wood [mailto:o...@buserror.net] > Sent: Saturday, June 11, 2016 9:51 AM > To: Arnd Bergmann; linuxppc-dev@lists.ozlabs.org > Cc: Mark Rutland; Ulf Hansson;

Re: [PATCH v13 01/16] PCI: Let pci_mmap_page_range() take resource address

On Wed, Jun 22, 2016 at 8:22 AM, Bjorn Helgaas wrote: > On Tue, Jun 21, 2016 at 09:32:49PM -0700, Yinghai Lu wrote: > > If sparc is broken, let's make this a tiny sparc-only patch that fixes > only the breakage -- no cleanup or restructuring. Then we can do the > more

[PATCH v2 2/2] powerpc/fadump: parse fadump reserve memory size based on memory range

Currently, memory for fadump can be specified with fadump_reserve_mem=size, where only a fixed size can be specified. Add the below syntax as well, to support conditional reservation based on system memory size: fadump_reserve_mem=:[,:,...] This syntax helps using the same commandline

Re: cpuidle broken on mainline

Hi, On 06/22/2016 08:46 PM, Anton Blanchard wrote: > Hi, > > I was noticing some pretty big run to run variations on single threaded > benchmarks, and I've isolated it cpuidle issues. If I look at > the cpuidle tracepoint, I notice we only go into the snooze state. > > Do we have any known bugs

RE: Kernel 4.7: PAGE_GUARDED and _PAGE_NO_CACHE

Christian, i think Darren patch override some memory region that on kernel.org was different and this make the kernel patched run and work Luigi Da: Christian Zigotzky [chzigot...@xenosoft.de] Inviato: mercoledì 22 giugno 2016 21.07 A: Benjamin

Re: [RFC PATCH v2 05/18] sched: add task flag for preempt IRQ tracking

On Wed, Jun 22, 2016 at 11:40 AM, Josh Poimboeuf wrote: > On Wed, Jun 22, 2016 at 11:26:21AM -0700, Andy Lutomirski wrote: >> > >> > So are you suggesting something like: >> > >> > .macro ENTRY_CALL func pt_regs_offset=0 >> > call \func >> > 1:

[PATCH v2 0/2] powerpc/fadump: support memory range syntax for fadump memory reservation

This patchset adds support to input system memory range based memory size for fadump reservation. The crashkernel parameter already supports such syntax. The first patch refactors the parsing code of crashkernel parameter for reuse. The second patch uses the newly refactored parsing code to

[PATCH v2 1/2] refactor code parsing size based on memory range

Currently, crashkernel parameter supports the below syntax to parse size based on memory range: crashkernel=:[,:,...] While such parsing is implemented for crashkernel parameter, it applies to other parameters with similar syntax. So, move this code to a more generic place for code

[PATCH] cpuidle/powernv: Fix snooze timeout

Snooze is a poll idle state in powernv and pseries platforms. Snooze has a timeout so that if a cpu stays in snooze for more than target residency of the next available idle state, then it would exit thereby giving chance to the cpuidle governor to re-evaluate and promote the cpu to a deeper idle