eeee78cf77
of the TRACE_DEFINE_ENUM() macro that can be used by tracepoints. Tracepoints have helper functions for the TP_printk() called __print_symbolic() and __print_flags() that lets a numeric number be displayed as a a human comprehensible text. What is placed in the TP_printk() is also shown in the tracepoint format file such that user space tools like perf and trace-cmd can parse the binary data and express the values too. Unfortunately, the way the TRACE_EVENT() macro works, anything placed in the TP_printk() will be shown pretty much exactly as is. The problem arises when enums are used. That's because unlike macros, enums will not be changed into their values by the C pre-processor. Thus, the enum string is exported to the format file, and this makes it useless for user space tools. The TRACE_DEFINE_ENUM() solves this by converting the enum strings in the TP_printk() format into their number, and that is what is shown to user space. For example, the tracepoint tlb_flush currently has this in its format file: __print_symbolic(REC->reason, { TLB_FLUSH_ON_TASK_SWITCH, "flush on task switch" }, { TLB_REMOTE_SHOOTDOWN, "remote shootdown" }, { TLB_LOCAL_SHOOTDOWN, "local shootdown" }, { TLB_LOCAL_MM_SHOOTDOWN, "local mm shootdown" }) After adding: TRACE_DEFINE_ENUM(TLB_FLUSH_ON_TASK_SWITCH); TRACE_DEFINE_ENUM(TLB_REMOTE_SHOOTDOWN); TRACE_DEFINE_ENUM(TLB_LOCAL_SHOOTDOWN); TRACE_DEFINE_ENUM(TLB_LOCAL_MM_SHOOTDOWN); Its format file will contain this: __print_symbolic(REC->reason, { 0, "flush on task switch" }, { 1, "remote shootdown" }, { 2, "local shootdown" }, { 3, "local mm shootdown" }) -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAABAgAGBQJVLBTuAAoJEEjnJuOKh9ldjHMIALdRS755TXCZGOf0r7O2akOR wMPeum7C+ae1mH+jCsJKUC0/jUfQKaMt/UxoHlipDgcGg8kD2jtGnGCw4Xlwvdsr y4rFmcTRSl1mo0zDSsg6ujoupHlVYN0+JPjrd7S3cv/llJoY49zcanNLF7S2XLeM dZCtWRLWYpBiWO68ai6AqJTnE/eGFIqBI048qb5Eg8dbK243SSeSIf9Ywhb+VsA+ aq6F7cWI/H6j4tbeza8tAN19dcwenDro5EfCDY8ARQHJu1f6Y3+DLf2imjkd6Aiu JVAoGIjHIpI+djwCZC1u4gi4urjfOqYartrM3Q54tb3YWYqHeNqP2ASI2a4EpYk= =Ixwt -----END PGP SIGNATURE----- Merge tag 'trace-v4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "Some clean ups and small fixes, but the biggest change is the addition of the TRACE_DEFINE_ENUM() macro that can be used by tracepoints. Tracepoints have helper functions for the TP_printk() called __print_symbolic() and __print_flags() that lets a numeric number be displayed as a a human comprehensible text. What is placed in the TP_printk() is also shown in the tracepoint format file such that user space tools like perf and trace-cmd can parse the binary data and express the values too. Unfortunately, the way the TRACE_EVENT() macro works, anything placed in the TP_printk() will be shown pretty much exactly as is. The problem arises when enums are used. That's because unlike macros, enums will not be changed into their values by the C pre-processor. Thus, the enum string is exported to the format file, and this makes it useless for user space tools. The TRACE_DEFINE_ENUM() solves this by converting the enum strings in the TP_printk() format into their number, and that is what is shown to user space. For example, the tracepoint tlb_flush currently has this in its format file: __print_symbolic(REC->reason, { TLB_FLUSH_ON_TASK_SWITCH, "flush on task switch" }, { TLB_REMOTE_SHOOTDOWN, "remote shootdown" }, { TLB_LOCAL_SHOOTDOWN, "local shootdown" }, { TLB_LOCAL_MM_SHOOTDOWN, "local mm shootdown" }) After adding: TRACE_DEFINE_ENUM(TLB_FLUSH_ON_TASK_SWITCH); TRACE_DEFINE_ENUM(TLB_REMOTE_SHOOTDOWN); TRACE_DEFINE_ENUM(TLB_LOCAL_SHOOTDOWN); TRACE_DEFINE_ENUM(TLB_LOCAL_MM_SHOOTDOWN); Its format file will contain this: __print_symbolic(REC->reason, { 0, "flush on task switch" }, { 1, "remote shootdown" }, { 2, "local shootdown" }, { 3, "local mm shootdown" })" * tag 'trace-v4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (27 commits) tracing: Add enum_map file to show enums that have been mapped writeback: Export enums used by tracepoint to user space v4l: Export enums used by tracepoints to user space SUNRPC: Export enums in tracepoints to user space mm: tracing: Export enums in tracepoints to user space irq/tracing: Export enums in tracepoints to user space f2fs: Export the enums in the tracepoints to userspace net/9p/tracing: Export enums in tracepoints to userspace x86/tlb/trace: Export enums in used by tlb_flush tracepoint tracing/samples: Update the trace-event-sample.h with TRACE_DEFINE_ENUM() tracing: Allow for modules to convert their enums to values tracing: Add TRACE_DEFINE_ENUM() macro to map enums to their values tracing: Update trace-event-sample with TRACE_SYSTEM_VAR documentation tracing: Give system name a pointer brcmsmac: Move each system tracepoints to their own header iwlwifi: Move each system tracepoints to their own header mac80211: Move message tracepoints to their own header tracing: Add TRACE_SYSTEM_VAR to xhci-hcd tracing: Add TRACE_SYSTEM_VAR to kvm-s390 tracing: Add TRACE_SYSTEM_VAR to intel-sst ... |
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.. | ||
whci | ||
bcma-hcd.c | ||
ehci-atmel.c | ||
ehci-dbg.c | ||
ehci-exynos.c | ||
ehci-fsl.c | ||
ehci-fsl.h | ||
ehci-grlib.c | ||
ehci-hcd.c | ||
ehci-hub.c | ||
ehci-mem.c | ||
ehci-msm.c | ||
ehci-mv.c | ||
ehci-mxc.c | ||
ehci-omap.c | ||
ehci-orion.c | ||
ehci-pci.c | ||
ehci-platform.c | ||
ehci-pmcmsp.c | ||
ehci-ppc-of.c | ||
ehci-ps3.c | ||
ehci-q.c | ||
ehci-sched.c | ||
ehci-sead3.c | ||
ehci-sh.c | ||
ehci-spear.c | ||
ehci-st.c | ||
ehci-sysfs.c | ||
ehci-tegra.c | ||
ehci-tilegx.c | ||
ehci-timer.c | ||
ehci-w90x900.c | ||
ehci-xilinx-of.c | ||
ehci.h | ||
fhci-dbg.c | ||
fhci-hcd.c | ||
fhci-hub.c | ||
fhci-mem.c | ||
fhci-q.c | ||
fhci-sched.c | ||
fhci-tds.c | ||
fhci.h | ||
fotg210-hcd.c | ||
fotg210.h | ||
fsl-mph-dr-of.c | ||
fusbh200-hcd.c | ||
fusbh200.h | ||
hwa-hc.c | ||
imx21-dbg.c | ||
imx21-hcd.c | ||
imx21-hcd.h | ||
isp116x-hcd.c | ||
isp116x.h | ||
isp1362-hcd.c | ||
isp1362.h | ||
Kconfig | ||
Makefile | ||
max3421-hcd.c | ||
ohci-at91.c | ||
ohci-da8xx.c | ||
ohci-dbg.c | ||
ohci-exynos.c | ||
ohci-hcd.c | ||
ohci-hub.c | ||
ohci-jz4740.c | ||
ohci-mem.c | ||
ohci-nxp.c | ||
ohci-omap3.c | ||
ohci-omap.c | ||
ohci-pci.c | ||
ohci-platform.c | ||
ohci-ppc-of.c | ||
ohci-ps3.c | ||
ohci-pxa27x.c | ||
ohci-q.c | ||
ohci-s3c2410.c | ||
ohci-sa1111.c | ||
ohci-sm501.c | ||
ohci-spear.c | ||
ohci-st.c | ||
ohci-tilegx.c | ||
ohci-tmio.c | ||
ohci.h | ||
oxu210hp-hcd.c | ||
oxu210hp.h | ||
pci-quirks.c | ||
pci-quirks.h | ||
r8a66597-hcd.c | ||
r8a66597.h | ||
sl811_cs.c | ||
sl811-hcd.c | ||
sl811.h | ||
ssb-hcd.c | ||
u132-hcd.c | ||
uhci-debug.c | ||
uhci-grlib.c | ||
uhci-hcd.c | ||
uhci-hcd.h | ||
uhci-hub.c | ||
uhci-pci.c | ||
uhci-platform.c | ||
uhci-q.c | ||
xhci-dbg.c | ||
xhci-ext-caps.h | ||
xhci-hub.c | ||
xhci-mem.c | ||
xhci-mvebu.c | ||
xhci-mvebu.h | ||
xhci-pci.c | ||
xhci-plat.c | ||
xhci-rcar.c | ||
xhci-rcar.h | ||
xhci-ring.c | ||
xhci-trace.c | ||
xhci-trace.h | ||
xhci.c | ||
xhci.h |